2014 NFREC Beef/Forage Day PROCEEDINGS
Friday, October 3, 2014
University of Florida Extension/IFAS educational programs are made available to any individual without regards to race, color, sex, age, handicap or national origin. Participants with disabilities requiring special accommodations please contact Marianna NFREC at least 5 working days prior to the event. BEEF FORAGE DAY COMMITTEE
Dr. Ann Blount Dr. Nicolas DiLorenzo Dr. Jose Dubeux Mr. Shep Eubanks Ms. Tina Gwin Dr. Cliff Lamb Ms. Judy Ludlow Mr. Doug Mayo Dr. Cheryl Mackowiak Mr. Mark Mauldin Mr David Thomas
UNIVERSITY OF FLORIDA, ADMINISTRATION
Dr. Bernie Machen, President, University of Florida Dr. Jack Payne, Vice President for Agriculture and Natural Resources Dr. Geoffrey Dahl, Professor and Dept. of Animal Sciences Chair Dr. Rob Gilbert, Professor and Dept. of Agronomy Chair Dr. Nick Comerford, Professor and NFREC Center Director Dr. Cliff Lamb, Professor and NFREC Assistant Director Mr. David Thomas, Beef Unit Manager and Bull Test Foreman
Appreciation is expressed to the following NFREC staff members that are involved or assist with the NFREC Beef Cattle and Forage programs.
NFREC Marianna Beef Unit NFREC Marianna Beef/Forage Labs Pete Folsom Don Jones Mark Foran Jeff Jones Olivia Helms Charles Nowell NFREC Marianna Office Staff David Thomas Gina Arnett Cole Wood Tina Gwin
NFREC Marianna Maintenance NFREC Marianna Farm Crew Ray Jordan Jim Bob Baxter Ray Morgan Bennie Toole
2014 NFREC Beef/Forage Field Day Sponsors/Exhibitors:
AFG Feed, LLC Crop Production Services, Inc. Dow AgroSciences Farm Credit of Northwest Florida Mix 30, Liquid Feed Quality Liquid Feeds Vigortone Ag Products W.B. Flemming Company Westway Feeds Zoetis Animal Health
TOPICS AND SPEAKERS
Perennial Grass Species Demonstration Jose Dubeux, UF State Forage Specialist
Annual Forage Options Demonstration Ann Blount, UF Forage Breeder
Fertilization Options for Bahiagrass Cheryl Mackowiak, UF State Soils Specialist
Complementing hay quality and supplementation Nicolas DiLorenzo, UF State Extension Beef Specialist
Scouting and Controlling Pests in Pastures Russ Mizell. UF State IPM Specialist
Calving Season Economics Chris Prevatt, UF Livestock Economist
Hay and Haylage Economics Demonstration Mark Mauldin, UF Extension County Agent
Selecting a bull for the cowherd Cliff Lamb, UF State Extension Beef Specialist
PERENNIAL WARM-SEASON GRASSES: THE BASIS FOR LIVESTOCK PRODUCTION SYSTEMS IN FLORIDA
José Dubeux, Ann Blount, and E. Lawson Mozley III
1. INTRODUCTION
Perennial warm-season grasses are the backbone of most livestock operations in Florida. They provide feed in numerous ways, including grazing, hay, haylage, and stockpiled forage. Perennial grasses present several advantages over annual species. Once they are established, there is no additional annual cost with seeds and land preparation. Also, perennial species take advantage of available moisture and nutrients throughout the growing season, more efficiently using the natural resources available for longer periods. In Florida, the most planted warm- season perennial grasses are Bahiagrass (Paspalum notatum Flüggé), Bermudagrass [Cynodon dactylon (L.) Pers.], Stargrass (Cynodon nlemfuensis Vanderyst var. nlemfuensis), Limpograss [Hemarthria altissima (Poir.) Stapf & C.E. Hubb.]. Native species such as eastern gamagrass [Tripsacum dactyloides (L.) L.] may also occur in rangelands and are important sources of feed for wildlife and livestock.
2. BAHIAGRASS
Bahiagrass is the most planted perennial warm-season grass in Florida with over two million acres of pastureland. The reason for the large adoption of bahiagrass by producers is due to its tolerance to low soil fertility and low input management systems (Newman et al. 2014). There are several bahiagrass cultivars, including Pensacola, Tifton-9, UF Riata, TifQuik, Argentine, and Paraguay. There are differences among cultivars in light sensitivity, seed production, growth habit, and proportion of hard seeds. Argentine bahiagrass is more light sensitive than UF Riata. As a result, UF Riata grows longer into the Fall season. This may be advantageous if the producer is not planning to overseed the pasture with cool-season forages. Shorther growing season of Argentine, on the other hand, will allow earlier planting of cool- season forages in early Fall. Some of these cultivars have more upright growth (e.g. Tifton-9) and are also a good option for hay fields. In recent research developed in Ona, FL by Vendramini et al. (2013), Argentine had greater crude protein but reduced digestibility (IVDOM) concentrations when compared to Pensacola, Tifton 9, and UF Riata (Table 1). In the same study, grazing bahiagrass every four weeks resulted in approximately 50% increase in herbage accumulation, compared to the two-weeks grazing interval (Table 2). Argentine and Pensacola had greater root and rhizome mass than Tifton 9 and UF Riata when grazed every two weeks. In general, the authors concluded that Argentine is a productive and persistent bahiagrass for beef cattle using limited N fertilization and frequent grazing in Florida. More information on the establishment and management of bahiagrass in Florida is available in the UF/IFAS EDIS publication SS-AGR-332 http://edis.ifas.ufl.edu/pdffiles/AG/AG34200.pdf
Table 1. Nutritive value of bahiagrass cultivars under grazing; Ona, FL.
Cultivar Crude Protein (%) Digestibility (%) Argentine 13.2 53.8 Pensacola 12.9 54.1 Tifton 9 12.4 55.3 UF Riata 12.0 55.1 Standard error 0.04 0.6 †Within columns, means followed by the same lowercase letter are not different (P > 0.05) Adapted from Vendramini et al. (2013)
Table 2. Herbage accumulation of bahiagrass cultivars grazed every 2 weeks or every 4 weeks; Ona, FL.
Herbage accumulation (lbs./acre) Cultivar Year 2010 2011
Two weeks 4550 b† 2320 b Four weeks 6513 a 4372 a †Within columns, means followed by the same lowercase letter are not different (P > 0.05) Adapted from Vendramini et al. (2013)
Table 3. Herbage Accumulation of bahiagrass cultivars under grazing; Ona, FL.
Herbage accumulation (lbs./acre) Cultivar Year 2010 2011
Argentine 5710 b† 3836 a Pensacola 5264 c 3033 c Tifton 9 6156 ab 3301 c UF Riata 6245 a 3569 b †Within columns, means followed by the same lowercase letter are not different (P > 0.05) Adapted from Vendramini et al. (2013)
3. BERMUDAGRASS
Bermudagrass is also widespread in Florida, and it is used both for grazing and for hay. Numerous cultivars were released, including Coastal, Swanee, Coastcross-1, Callie, Alicia, Tifton 44, Tifton 78, Tifton 85, Florakirk, and Jiggs. Bermudagrass requires better soil fertility compared to bahiagrass. Nutrient extraction from bermudagrass hay fields is high, particulalrly N and K. Thus, replenishing soil fertility is mandatory in order to improve yield and persistence of bermudagrass fields. Mixing swards of bermudagrass and legumes, such as Alfalfa or perennial peanut, has also been used by some producers as a way to improve forage quality and add N to the system. Stargrass is also widely adopted in South Florida, for grazing, hay, and haylage production. It is not as cold tolerant as bermudagrass because it is a non-rhizomatous species. In Florida, it is most commonly used South of I-4. Jiggs bermudagrass has been showing greater performance in poorly drained soils compared to other bermudagrasses cultivars and stargrass (Table 4). Tifton 85 usually ranks among the top regarding herbage digestibility and performs well in well-drained and fertilized soils. More information on the establishment and management of bermudagrass production in Florida is available in the UF/IFAS EDIS publication SS-AGR-60 http://edis.ifas.ufl.edu/pdffiles/AA/AA20000.pdf.
Table 4. Herbage accumulation and nutritive value of bermudagrass and stargrass cultivars grown in Ona, FL.
Cultivar Herbage accumulation Crude Protein Digestibility (lbs./acre) (% of DM) (% of DM) Jiggs 4,104 11.6 58.4 Coast-cross-2 2,757 12.9 63.2 Tifton 85 2,650 10.2 63.9 Florakirk bermudagrass 3,390 11.6 58.0 Florico stargrass 3,274 12.0 61.7 Standard Error 357 1.9 2.2 Adapted from Vendramini et al. (2010).
4. LIMPOGRASS
Limpograss has been succesfuly adopted in south Florida. It has been used as a stockpiled forage to fill the forage gap during the Fall/Winter seasons. Limpograss also adapts well in poor drained soils, fitting well in many Florida areas. Its digestibility decays slower than other grasses, such as bermudagrasses and bahiagrass. Released cultivars include Floralta, Bigalta, Redalta, Greenalta, and recently the hybrids 1 and 4F (Table 5). If stockpiled, it may require protein supplementation to enhance livestock performance and improve efficiency of its utilization. More information on the establishment and management of limpograss in Florida is available in the UF/IFAS EDIS publication SS-AGR-320 http://edis.ifas.ufl.edu/pdffiles/AG/AG33000.pdf
Table 5. Herbage accumulation and nutritive value of limpograss cultivars grown in Ona, FL.
Cultivar Herbage accumulation† Crude Protein† Digestibility† (lbs./acre) (% of DM) (% of DM) 10 10,349 8.1 59.0 4F 9,279 8.2 57.7 Floralta 8,476 9.0 57.3 32 7,494 8.7 56.6 1 7,137 9.0 58.6 34 6,959 8.1 57.4 Standard Error 803 0.4 1.3 Adapted from Wallau (2013). †Data are means across two levels of pre-grazing light interception, two levels of post-grazing stubble height, and two replicates.
Table 6. Average daily gain (ADG) of crossbred heifers continously grazing limpograss to different pasture heights with or without supplement.
Average daily gain Pasture height (inches) Non-supplemented Supplemented† ------Lbs./head/day ------8 1.0 1.4 16 1.4 1.2 24 0.7 1.2 †Supplement consisted of a 44% CP corn-urea fed at a rate of 1.4 lb/day. Source: Newman et al. (2014)
Figure 1. Cattle in a Limpograss pasture in Florida. Credit: Yoana Newman, UF/IFAS.
5. OTHER GRASSES
Native species naturally occuring in Florida rangelands also provide feed for wildlife and livestock. Eastern gamagrass is a potential species to be explored, particularly because its early Spring growth and late growth into the Fall, potentially extending the grazing season. It grows weel in poor drained soils. Because it is a bunch grass, it requires a more careful management than stoloniferous grasses (Roberts and Kallenbach, 1999).
6. CONCLUDING REMARKS
Perennial warm-season grasses are important components of Florida livestock production systems. Several options are available and choices are based on the environment (temperature, soil, drainage, fertility, pests and diseases), level of intensification of the production system (fertilization, irrigation, grazing/harvest management), and use (hay, grazing, haylage, stockpiling).
7. REFERENCES
Newman, Y., J.Vendramini, A. Blount. 2014. Bahiagrass (Paspalum notatum): Overview and Management. EDIS SS-AGR-332, Agronomy Department, UF/IFAS Extension. http://edis.ifas.ufl.edu/pdffiles/AG/AG34200.pdf
Newman, Y., J. Vendramini, L.E. Sollenberger, K. Quesenberry. 2014. Limpograss (Hemarthria altissima): overview and management. EDIS SS-AGR-320, Agronomy Department, UF/IFAS Extension. http://edis.ifas.ufl.edu/pdffiles/AG/AG33000.pdf
Roberts, C., R. Kallenbach. 1999. Estaren Gamagrass. Agricultural MU Guide. Published by MU Extension, University of Missouri, Columnia. http://extension.missouri.edu/explorepdf/agguides/crops/g04671.pdf
Vendramini, J.M.B., A. Adesogan, M.L.A. Silveira, L.E. Sollenberger, O.C.M. Queiroz, W.F. Anderson. 2010. Nutritive value and fermentation parameters of warm-season grass silage. The Professional Animal Scientist, 26:193-200.
Vendramini, J.M.B., L.E. Sollenberger, A.R.S. Blount, A.D. Aguiar, L. Galzerano, A.L.S. Valente, E. Alves, L. Custodio. 2013. Bahiagrass cultivar response to grazing frequency with limited nitrogen fertilization. Agronomy Journal, 105(4):938-944.
Wallau, M.O. 2013. Evaluation of limpograss [Hemarthria altissima] breeding lines for use in Florida forage-livestock systems. Master Thesis, UF/IFAS, Agronomy Department. 121 p. Available at http://ufdc.ufl.edu/UFE0046359/00001
ANNUAL WARM-SEASON GRASSES: ONE ALTERNATIVE FOR LIVESTOCK PRODUCTION SYSTEMS IN FLORIDA
Ann Blount and José Dubeux
INTRODUCTION
After a very hard few years with drought conditions and difficulty with timely hay harvesting across the state, many of us are still concerned about having low hay inventories going into the winter. Cool-season forages are expensive and there will be limited seed availability for oats and cereal rye. Last year, the summer and fall rains hampered hay harvests and postponed planting small grains and ryegrass until late in the year. This year appears to be on a similar pathway. While many of us are baling summer perennial grass hay and contemplating fall forage plantings, it may be time to think ahead to next spring and if summer annual grasses may have a possible fit in our livestock operations. While the backbone of the Florida cattle industry relies on perennial grass species, like bahiagrass, bermudagrass and limpograss, some of us plant a portion of our acres in summer annual grasses. Summer annual forages, like millet, sorghum- sudangrass, and crabgrass, offer high quality and high yielding forages for livestock. Certain classes of livestock, such as stockers, replacement heifers, first-calf heifers, or dairy cows, may well benefit from these high quality annual forages. Summer annuals grasses may also be used in rotation when renovating a pasture where weeds or diseases are prevalent or when changing varieties or types of perennial forage crops.
Pearl millet, forage sorghum, sudangrass and sorghum-sudan hybrids are annual, warm- season, seeded grasses that grow quickly in the spring and summer months and offer high- yielding and high-quality forage. These forages require cultivated land or may be stripped or no- tilled into a pasture following small grains, after the winter forage has been grazed down. Row crop and vegetable crop producers may also use millet, forage sorghum, or sorghum-sudangrass in rotation with high valued crops to maintain weed control and/or prevent erosion, while provide their livestock with quality forage. Sometimes these forages are used when renovating pastures, particularly when trying to eliminate existing stands of perennial grasses. They can successfully shade out bahiagrass and bermudagrass. While these quick growing annuals offer high nutritive quality, they can present a few management concerns. Nitrate accumulation can occur in all of these grasses. Weather and crop management may contribute to the rapid accumulation of nitrates in the plant tissue. This generally occurs during periods of low rainfall or low humidity with plants heavily fertilized with N. When hay is cut during or just following a period of drought, nitrate levels may be elevated. Prussic acid (HCN) poisoning is not a concern in millet, however, it is with forage sorghum, sudangrass, and sorghum-sudangrass and care should be taken with livestock consuming these forages during periods of drought or frost.
Pearl millet, forage sorghum, sudangrass and sorghum-sudangrass may also be used for creep grazing, green chop, haylage, silage or hay. The large stems are often hard to dry for making hay, and a hay conditioner would best be used to hasten the drying period. Often these types of summer forages are ensiled rather than harvested for hay. Equine should not be fed sorghum- sudangrass hay because of health issues related to cystitis. Regardless of the class of livestock you are feeding, care needs to be taken to prevent any issues with nitrates and prussic acid concentrations in sensitive animals.
Pearl millet, forage sorghum, and sorghum-sudangrass seed is often readily available and there are some very good varieties on the market. More information on planting and management of these two crops can be found in EDIS extension publication http://edis.ifas.ufl.edu/ag157
Performance and yield of varieties are tested annually in Georgia and Florida and results for millet and sorghum-sudangrass may be found at the University of Georgia’s variety testing website under Summer Annual Forages: http://www.swvt.uga.edu/
Pearl millet varieties include Tifleaf III and several Southern State varieties, all well adapted to Florida. Pearl millet should not be confused with Japanese millet, browntop millet, or proso millet. These are short growing millets, popular in wildlife plantings or for quick cover to prevent soil erosion. Forage yields of these millets are considerably lower than that of pearl millet and are not usually recommended for livestock forage plantings.
Some of the forage sorghums and sorghum-sudangrass hybrids now have the brown midrib (BMR) trait, which enhances the digestibility of the forage by as much as 40%. Sudangrass is a finer grass than sorghum-sudangrass and generally its forage is lower yielding.
Lastly, one favorite summer annual forage is Crabgrass. It is a fine-stemmed grass that can be grazed or cut for hay. It often volunteers in pastures or fields that have recently been tilled. Crabgrass can be planted, however commercial varieties are limited to “Red River Crabgrass” and “Quick-N-Big”, developed at the Roberts Noble Foundation of Ardmore, Oklahoma. Crabgrass can be managed as an annually planted forage. It mixes very well with legumes and other types of summer grasses. It is very palatability and has excellent forage quality with CP at about 14% and % IVDMD in the upper 70s (78-79%) when grazed or cut for hay in the vegetative stage. As the plant matures, as with most grasses, its forage quality declines. Planting crabgrass fits well in open land situations where planting annual winter forages, such as ryegrass, oats, rye or wheat, for early grazing is the goal. The periods for winter annuals and crabgrass are complementary and allow for slight overlap in seasonal forage production. Shallow tillage prior to planting winter annuals incorporates crabgrass seed and usually results in good crabgrass stands the following spring, without the need for spring tillage. When the crabgrass stand is established, fertilization is the primary management practice required. Crabgrass growth in Florida declines by late August or early September. More information about crabgrass can be found in EDIS at http://edis.ifas.ufl.edu/ag195
Thin ahead for next year when planning to plant summer annual forage grasses. Perhaps these summer annual forages might find a fit and help to extend the forage calendar on your livestock operation.
BAHIAGRASS FERTILIZATION OPTIONS
C.L. Mackowiak1, J. Bearden2, and J. Shirley1 1UF-IFAS NFREC, Quincy, FL and 2Okaloosa County Extension, Crestview, FL
Background Bahiagrass (Paspalum notatum Flüggé.) is a perennial, warm-season, tropical grass. Its origin is in South America, where it is commonly found in a region encompassing parts of Uruguay, Paraguay, Argentina, and Brazil, on soils similar to soils found in Florida (i.e., Alfisols, Ultisols, and a small amount of Entisols). The Alfisols, which are found under much of the northeastern Argentinean grasslands but are much less common in Florida, tend to be moderately acidic and have greater inherent fertility than Ultisols (red soils), which dominate much of the U.S. Southern Coastal Plain. Ultisols are moderately acidic and have relatively lower fertility, particularly base cations; potassium (K), calcium (Ca), and magnesium (Mg). Entisols (deep sands) make up a large portion of Florida and these soils are the least fertile, as they contain few clay minerals or organic matter to contribute nutrients. Due to its point of origin, it is understandable that early bahiagrass introductions, such as Pensacola and Argentine, survive well in moderately acidic soils with modest amounts of fertilizer. However, simply surviving is often not good enough in production agriculture; we also demand high yields.
As with most crops, higher yielding bahiagrass cultivars (such as Tifton-9 and Riata), require more nutrients (fertilizer) to support the additional biomass. One can use livestock as an analogy (i.e., bigger cattle require more inputs). To take it a step further, cattle will grow only as large as their genetics and environment allow. The same is true of plants. Bahiagrass will not grow beyond its environmental and genetic limitations. Therefore, too much fertilizer, like too much food, should be avoided. It is wasteful in terms of fertilization costs and it may increase plant susceptibility to pest pressures, particularly if too much nitrogen (N) is applied. In terms of genetics, even under the most optimal conditions, Pensacola and Argentine bahiagrass will not out-yield Tifton-85 bermudagrass, or the newer, high-yielding bahiagrass cultivars. However, the older cultivars may out-survive the higher-yielding cultivars under intense, continuous grazing pressure. Common bermudagrass will often out-grow, and thereby, out-compete the older bahiagrass varieties under high N fertilization in a pasture. Less is known about common bermudagrass competition with the newer bahiagrass cultivars. Higher N fertilization rates also feed weeds. Without repeated grazing pressure on weeds, such as smut grass, they soon spread throughout the pasture.
Obtaining a soil fertility report is the first step in determining how much fertilizer to apply to a bahiagrass pasture. The second step is to determine how you are going to manage your pasture. Will it be continuously grazed? What are the stocking rates (high, moderate, low)? Will you cut hay, harvest seed, or other practice besides grazing? Pasture management is an important aspect in soil fertility management, as we are trying to balance nutrient export with import. Table 1 provides some relative differences in nutrient removal (export) from a hypothetical bahiagrass pasture vs. hay field over the course of a growing season. Under optimal conditions (good rotation with no congregation areas, no excessive rainfall), pasture nutrients are mostly recycled. In a hay system, most of the biomass (nutrients/fertilizer) is exported with each hay cutting. Nitrogen is commonly resupplied in both systems (pasture and hay) in part, because a percent of N is loss via gaseous emissions (NH3, N2O, N2) and from nitrate (NO3-N) leaching (moves below the root zone with excessive rainfall or irrigation).
Table 1. Estimated yield to produce either 200 lbs of beef or 4 tons of bahiagrass hay. Yield per acre N P2O5 K2O Ca Mg S ------lbs per acre------200 lb Beef* 6 5 1 ------4 tons Hay** 154 42 170 26 19 15 *Taken from Mitchell. 1999. Nutrient removal by Alabama crops. Factsheet ANR-449. **Adapted from Mackowiak et al. 2013. Getting the most out of bahiagrass fertilization. EDIS SL249.
Since N has a direct impact on yield and excessive N applications are harming our local watershed (Jackson Blue Spring), our bahiagrass pasture demonstration showcases two aspects of pasture management: 1) Nitrogen fertilizer options 2) grazing pressure effects on bahiagrass health and rooting. Pasture plants with deep roots will lessen N leaching losses during high rainfall periods and greater root mass allows for better nutrient capture, overall.
Concern that excess nutrients are entering our water bodies and increasing fertilizer costs, means that we should try to increase our fertilizer use efficiency (more biomass produced per pound of nutrient applied). We can regulate fertilizer supply in terms of Enhanced Efficiency Fertilizers (EEFs), where we better match the fertilizer release to the plant, when it needs it. Most of this effort has been directed at N. Nitrogen EEFs can be divided into: 1) slow-release and 2) controlled- release types. Slow-release N typically originates from manures, compost, litters, biosolids, etc. These organic materials release plant-available N slowly, through mineralization of the organic N. Controlled-release N is typically based upon treating (coating) a mineral N fertilizer (often urea) to control its release to the plant. There are polymer coatings, urease inhibitor coatings, nitrification inhibitor coatings and coatings that combine both, urease and nitrification inhibitors. Other ways to increase fertilizer use efficiency is to 3) split-apply a conventional fertilizer, 4) adjust fertilizer rates to better match plant growth, 5) adjust fertilizer timing, or 6) different combinations of 1 through 5. A more efficient plant may also be developed but that will not be covered in this discussion.
We used some locally-available N fertilizer products, in order to demonstrate bahiagrass fertilizer options. As a demonstration, the data are merely a snapshot of what we observed in this one situation (low management, mid-season N application, modest rainfall). Additionally, the pasture demonstration is not replicated and limited to one location, so one should be extremely cautious when interpreting the results. We are pursuing state funding to continue this effort as multi-location experiments, in order to better describe the N fertilizer options available for pastures and hay fields, as well as substituting some N fertilizer by growing forage legumes.
Nitrogen Fertilizer Demonstration We applied five different N fertilizer options to plots (60 ft x 30 ft). We split the 60 ft length in half with temporary electric fencing to compare continuously grazed with rotational grazing. Each plot received a different N treatment (Fig. 1). The urea used on plots 2 and 3 came from a product with an analysis of 34-0-0, which is a combination of urea-N (75% of total N) and ammonium sulfate (25% of total N). Treatments from left to right: 1) no N was applied, 2) urea at 50 lbs N/acre, 3) urea split-applied at 50 lbs N initially and another 50 lbs N on August 14), 4) ESN- coated urea (polymer coating) at 100 lbs N, 5) Nutrisphere-coated urea (urease and nitrification inhibitor) at 100 lbs N, and 6) Class AA, dry, pelleted biosolids (GreenEdge) at 100 lbs total N (Fig. 1). The south half of plots were rotationally grazed, while the north half was continuously grazed.
Rotationally grazed North
Nutrisphere No N 34‐0‐0 34‐0‐0 ESN 6‐4‐0 Urea (50 lbs) Urea (100 lbs) Urea (100 lbs) Urea (100 lbs) Biosolids split (polymer) Inhibitors: Class AA urease (100 lbs) nitrification
Continuously grazed
Fig. 1. Pasture plot layout, with rotationally grazed on top and continuously grazed on bottom, under the same fertilizer treatments as the top.
Initial soil pH=5.8. Initial soil fertility using Mehlich-3 extraction method, was (in ppm): P=64, K=58, Ca=381, Mg=73, S=11, B=0.5, Fe=187, Mn=199, Zn=3.4, and Cu=1.3. All plots received 40 lbs K2O, 10 lbs S, and 5 lbs Mg.
We tracked soil surface N loss as ammonia (NH3) gas. Urea-N loss via NH3 gas emissions from the soil surface is well documented. However, if urea is applied under the soil or gets washed under the soil via rainfall or irrigation, gaseous losses are minimal. We used modified, inverted 2L soda bottles with a wick soaked in an acid to capture NH3 gas emissions. The acid converts the gas to NH4, which remains in solution, adsorbed to the wick. The wicks were then extracted approximately weekly, to estimate potential N emissions over time.
The wick system provides a qualitative estimate of N emissions as ammonia. We can roughly estimate potential losses, based upon the area covered by the collection bottle. However, there are potential errors associated with this method. Since it is an open system, some NH3 may escape without being captured, thereby underestimating losses. Additionally, the collectors cover a very small area. If we randomly have as much as a single extra fertilizer pellet in the sampling area or a pellet less, it will skew the emission loss estimates correspondingly higher or lower.
A plot of cumulative NH3 loss over time shows that without any N fertilizer application, there was a negligible (~ 1 lb/acre) NH3 loss, and all N treatments had greater NH3 release than the no N control (Fig. 2). The 34-0-0 urea/ammonium sulfate mineral fertilizer (~75% of N as urea) treatment at 50 lbs N/acre and 100 lbs N/acre should have had similar releases until the second 50 lb split application (August 15th). However, the split application demonstrated greater release during this time period. A 10% N loss as N is fairly representative of reports in the literature, as exemplified by the split treatment, thereby making the 50 lb treatment suspiciously low. After the th August 14 split application, there was a second jump in NH3 emissions from the split treatment, as expected. The biosolids fertilizer contains much of its N in the organic form (to be released upon mineralization), so we expected emissions to be below urea treatments but greater than the control. The rate of NH3 emissions from biosolids was relatively consistent over time, suggesting that it provided slow-release N to the crop during the test period.
The two coated urea fertilizers (polymer and urease/nitrification inhibitor), responded differently from one another and results are somewhat more difficult to interpret. We suspect that there may have been more fertilizer prill under the polymer coated sampler, than under the inhibitor coated sampler. However, assuming that the values are reasonable for the two products, what might explain these results? Focusing on the inhibitor coated product, we may consider the following: 1) the coating was working as advertised and therefore NH3 emissions were low (2%), 2) the coating dissolved with the first rains and the fertilizer quickly entered the soil before reacting , thereby lessening NH3 emissions, or 3) we simply had relatively less prill under this sampler. In comparison, the polymer coated product emissions suggest a mostly constant (controlled) release rate of urea from the polymer, which means that it performed as advertised. Unfortunately, NH3 gas emissions from this treatment were about 16% of total fertilizer N by 02 September (Fig. 2). Although the coating likely slowed release, perhaps following release, urea volatilized as NH3. Unlike row crops, where tillage or side dressing incorporates more of the fertilizer below the soil surface, all of our test fertilizers remained on the soil surface until they were transported under the soil with rainfall or dew. Additional research into the performance of these products in pastures and hay fields needs to be conducted.
Soil plant-available N (NH4 + NO3) analysis taken from 25 August showed all N products increased soil plant-available N, compared to the unfertilized control (Fig. 3). The split urea application, which received its second (50 lb N) application about 10 days prior to sampling, had greater plant-available N than the other N fertilizer treatments. Total soil N and forage N content will better help determine if applying 100 lbs N/ac as slow- or controlled-release products provided any greater N uptake and soil N conservation, than using 50 lbs N as a single urea application or 100 lbs N as a split urea application. These data (not yet analyzed) will be discussed at the field day. We plan to evaluate the economics of slow-release and controlled-release products, as it relates to forage performance in 2015.
20 No N fertilizer 50 lbs N: urea (73%) AS (27%) 100 lbs N: split (50 initial, 50 Aug 14th) (16%) 15 100 lbs N: polymer coated urea 100 lbs N: N inhibitor coated urea 100 lbs N: biosolids
10 (9%) (lbs N per acre) Split application 5 Ammonia volatilization Ammonia (4%)
(2%) (4%)
0 Jul Aug Sep Fig. 2. Estimated cumulative N emissions as NH3, beginning with first N application, 30 June, 2014.
Forage production from 30 June to 14 August was not measurably affected by N fertilization practices. Forage yields were similar among N treatments at approximately 0.6 tons per acre. In comparison, the control plot produced approximately 1 ton per acre. This is a good illustration of why replication is required to better discern between treatment responses and natural variability effects within a pasture study. It also demonstrates how a section of pasture, with a healthy stand may out-yield sections of pasture that may be less healthy or is more weed-infested, even though it receives significantly greater N fertilizer inputs.
As mentioned previously, overgrazing can weaken forages, making them less able to capture water, nutrients, or tolerate weather-related or pest pressures. We installed 4” diameter x 24” long PVC columns in some of the grazed and ungrazed plots, in order to observe the potential differences in above- and below-ground biomass due to N and grazing treatments. Primarily, we were interested in the effect continuous grazing vs rotational grazing might have on forage root growth. At the time of this publication, we had not excavated the columns from the pasture treatments, but past demonstrations with cool-season annuals showed that heavier grazing resulted in more shallow root systems (Fig. 4). 40
30
20
10 Soil inorganic N (lbs per acre)
0 r ) ) r r e a lit e to ds liz re p m bi li rti (u s ly hi so fe N ea po in io N 0 ur N b o 5 ( 0 0 N N N 0 N 10 10 00 10 1 Fig. 3 Soil inorganic N concentrations (0 to 6 inch depth) sampled 14 August, 2014.
Managing Towards a Healthy Pasture With adequate surface soil moisture and fertility, pasture plants can perform well with more shallow roots. However, dry periods often result in water stress rather quickly, particularly during the mid-summer months, when forage canopy water loss often exceeds water inputs. For example, rainfall for June, July and August, 2014 were 2.3, 5.7, and 2.6 inches, respectively. In comparison, water uptake requirements for the pasture (evapotranspirational losses) were approximately 5.1, 5.0, and 5.0 for June, July, and August, respectively. Our soils can hold approximately 1 inch of water per foot of depth. Even if rainfall met plant water demand, it would take at least a 5 foot depth of continuously moist soil to support this. Deep roots can reach deeper soil water reserves, if they exist (as well as soil N), allowing the forage to continue growing during dry periods, thereby feeding your herd. At the field demonstration, we will compare unfertilized with N fertilized excavated plant roots to see if we can observe differences within a 3-month (mid-season) change in N fertilization and grazing practices.
Fig. 4. Example of a PVC column inserted in a pasture of grazed triticale (February, 2013).
Summary Bahiagrass requires adequate and balanced nutrition in order to produce large amounts of quality forage. It also requires good grazing management to keep it healthy. Over the long-term, good management that supports a strong root system will result in a more efficient and sustainable pasture through water, fertilizer, herbicide, and energy savings. Slow- and controlled-release N fertilizers are being increasingly considered for use in pastures. They may provide insurance against excessive N losses but further testing is required to better define their benefits and limits under our ever-changing growing conditions.
CATTLE NUTRITION ON WINTER FORAGES Dr. Nicolas DiLorenzo State Beef Specialist, University of Florida NFREC
Complementing hay quality and supplementation
Despite the fact that North Florida’s weather is optimal in terms of rainfall and temperatures to allow a longer grazing season than most other beef production areas in the U.S., we are still not able to graze year round. During the year we have two periods in which, for different reasons, supplementation of beef cattle may be necessary in order to avoid productivity losses. Towards the end of the summer, shorter photoperiods (day length) and dropping temperatures are responsible for the yearly decreased in production of our bahiagrass pastures, which will eventually reach a dormancy stage by late fall, creating a gap in terms of grazing opportunities. On the other hand, at the end of the winter season (April-May), a typical decline in winter forages production occurs (if any planted planted), and at least in North Florida, we are faced with another forage availability gap, since our bermudagrass and bahiagrass fields may not be yet in full swing.
It is during those two periods when we typically have to resource to hay feeding and, depending on production objectives and body condition of cattle, perhaps even some grain or byproducts feeding. Hay is by far the most common supplemental feed used during the two periods of forage shortage described. However, as we often say, while hay may seem the cheapest feed in the operation, especially if produced from our own fields, may not be so if we consider the real cost of production, feeding labor, and most importantly waste. In order to develop a good nutrition strategy is recommended to test the hay for nutrient composition, and if necessary to seek advice from UF Extension personnel on how to interpret those test results and how to properly address any nutritional imbalances that may result from feeding only hay. The University of Florida Forage Extension Laboratory located at the Range Cattle Research and Education Center in Ona, FL provides affordable options for the analysis of samples for basic nutrient contents such as CP and TDN (http://rcrec‐ona.ifas.ufl.edu/agronomy/forage‐extension‐laboratory.shtml). An early analysis of the basic nutrients in the hay that will be used this season could help develop a sound supplementation program, allowing supplemental feed purchases, if needed, at a time when prices are at the lowest.
In order to start a basic balancing of nutrients using a calving date of January 1 as hypothetical, Table 1 shows the basic nutrient requirements of a 1,000 and a 1,200 lb cow with their expected hay intake based on quality, and potential supplemental needs to meet requirements. As you review the table you will realize how critical it is to have an accurate estimate of the nutrients provided by the hay, as these can vary greatly, especially in terms of crude protein (CP). Energy (expressed as Total Digestible Nutrients, TDN) is not greatly influenced by fertilization, but rather by time of cutting. As an example of the effect of fertilization on CP, at NFREC we have analyzed samples of bahiagrass hay ranging from 5.6 (unfertilized) to 10.4% (fertilized). For this example, we chose to use a value of CP of 7.0% as it was one of the most frequently reported values for bahiagrass hay. As observed in Table 1, that range of variation in CP could make a difference on whether protein needs to be supplemented to cows or not, in order to meet their basic nutrient requirements.
Supplemental feeds
In north Florida, we are fortunate to have a wide range of feedstuffs available for cattle supplementation. The abundance of byproducts from the peanut, cotton, corn, sugar, and soybean milling industries have been a great resource for cattle ranchers in the U.S. In addition, thanks to the technological advances in the feed manufacturing industries, in the southeastern U.S. we now have supplemental feeds available in a pelleted form, made from byproducts of local industries such as peanut shelling, cotton processing, and corn ethanol production. This represents an advantage for producers that may not have the resources (equipment, storage, etc.) to mix different feed byproducts into a balanced supplement. By mixing and pelleting certain feed byproducts it is quite possible to achieve a balance of nutrients that allows the use of one supplemental feed to provide a consistent amount of nutrients to meet the requirements. However, mixed feeds need to be tested for nutrient composition in order to ensure that the price paid for the supplement is fair and justifiable, based on the production objectives. Table 2 provides a list of common feedstuffs found in the southeastern U.S., as well as some commercial feed supplements and their analyzed nutrient composition. The nutrient profile and the cow requirements are then used in Table 3 to provide a guide of supplemental amounts to meet the needs of gestating beef cows.
Conclusions
In order to maximize profitability of the beef cattle enterprise, strategic feed supplementation needs to be considered an investment rather than a cost. During the fall, we typically observe a shortage of nutrient supply, when the summer forages quit producing and enter dormancy. It is very common during this time (which can be from November to May, depending on winter forage availability) to supplement hay in order to maintain body condition in cows. A recommended strategy is to test the hay to develop a nutrient balancing approach with supplemental feeds if needed, based on hay quality and potential intake. Many byproducts and manufactured feeds are available in North Florida to supplement cattle. Table 3 provides a guide of potential supplemental amounts based on feed type, however, keep in mind that this supplemental amounts are calculated only to meet the requirements of maintenance of a pregnant cow in the last trimester of gestation (typical situation of most herds in this area during the fall). Thus, if supplemental amounts in Table 3 are fed along with hay, the cows will not gain any body reserves; they will only maintain the pregnancy and their condition. In order to maximize production, a target body condition score of 5 to 6 (in a 1 to 9 scale) is recommended. Thus, if cows are entering the hay-feeding period a little thin, some adjustments in the nutrition program may need to take place to allow deposit more body reserves before calving.
Table 1. Basic nutrient requirements and supplemental needs of beef cows, 2 months before calving (approximately in November 1 for a hypothetical calving date of January 1), assuming they have a genetic potential to produce 10 lbs/milk per day at peak production. Supplemental CP and TDN needed are based on a DM intake of hay of 1.8% of their BW (Hersom, 2010) and hay nutrient analyses from unfertilized bahiagrass hay samples in North Florida (7.0 % CP and 52% TDN, DM basis).
Cow body weight (lbs) Item 1,000 1,200 1,400
CP required, lb/d 1.45 1.67 1.89 CP provided by hay, lb/d 1.26 1.51 1.76 CP shortage, lb/d 0.19 0.16 0.13
TDN required, lb/d 10.21 11.78 13.27 TDN provided by hay, lb/d 9.36 11.23 13.10 TDN shortage, lb/d 0.85 0.55 0.17
Table 2. Common supplemental feeds available in North Florida and their nutrient profile1. Nutrient content
CP, % TDN, % Moisture, Feedstuff (DM basis) (DM basis) %
50:50 corn gluten feed:soybean hulls pellets 17.5 78.5 10 Dried distillers grains plus solubles (DDGS) 29 98 11 Corn gluten feed pellets 22 80 10 Soybean hulls 13 77 10 Cottonseed meal 47 77 10 Molasses 6 74 23 Commercial peanut pellets (manufacturer A) 10.9 67 11 Commercial supplement (manufacturer B) 12.5 70 10 Commercial supplement (manufacturer C) 21.9 73 10.6 1The nutrient profile of commercial supplements is based on analyzed values of samples provided. Nutrient profile of common feedstuffs was obtained from published feed composition tables (NRC, 2000; Preston, 2012). All the commercial supplements described in this table are available and produced locally from a variety of byproducts including peanut pellets, corn screenings and distillers grains, amongst other ingredients. The manufacturers are intentionally maintained anonymous to avoid the endorsement of a particular product by the University of Florida during the diet balancing examples provided herein.
Table 3. Diet balancing example to provide supplementation to a 1,000 lb pregnant cow in the last trimester of pregnancy, using different feedstuffs. Assumptions: bahiagrass hay provided ad libitum (7.0 % CP and 52% TDN, DM basis) with an intake of 1.5% of the cow’s BW to allow a maximal supplemental amount of 0.3% of the cow’s BW (total DMI of 1.8% of BW).
Nutrient
CP, lb/d TDN, lb/d Item
Nutrients required 1.45 10.21 Hay intake of 15 lbs of DM/day (1.5% of BW) provides: 1.05 7.8 Shortage (amount needed to supplement) 0.45 2.41
Amounts of each supplement needed to meet requirements1: 3 lb/d of corn gluten feed (CGF) pellets provide: 0.59 2.16 5 lb/d of molasses (if no additional protein) provide: 0.23 2.85 3 lb/d of 50:50 CGF:soybean hulls pellets provide: 0.53 2.36 3 lb/d of dried distillers grains plus solubles (DDGS): 0.87 2.94 4 lb/d of commercial peanut pellets (manufacturer A): 0.44 2.68 4 lb/d of commercial supplement (manufacturer B) 0.50 2.80 3 lb/d of commercial supplement (manufacturer C) 0.66 2.19 1Note that not all feedstuffs may be able to cover both protein and energy needs in one feed. Use this as a guide to determine potential combinations of feedstuffs to meet the requirements.
References
Hersom, M. 2010. Basic Nutrient Requirements of Beef Cows. University of Florida, IFAS, Florida Coop. Ext. Serv., Animal Science Dept., EDIS Publication AN190. NRC. 2000. Nutrient Requirements of Beef Cattle. 7th ed. Natl. Acad. Press, Washington, DC. Preston, R. L. 2012. Feed Composition Tables. Beef Magazine. Available: http://fyi.uwex.edu/wbic/files/2010/12/2012FeedCompTables.pdf Accessed 9/10/14.
ATHERIGONA REVERSURA OR BERMUDAGRASS STEM MAGGOT (BSM) BY LIZA GARCIA AND RUSS MIZELL, NFREC-MARIANNA AND QUINCY, RESPECTIVELY
Scientific classification Kingdom: Animalia Phylum: Arthropoda Class: Insecta Order: Dipteraa Family: Muscidae Genus: Atherigona Specie: reversura Binomial name
Atherigona reversura Villaneuve (Diptera: Muscidae) Photo credits: Liza Garcia
ATHERIGONA REVERSURA or bermudagrass stem maggot is a muscid shoot-fly. The genus comprises more than 220 species, and some of them are very damaging pests in agriculture [2]. This small fly has an angular head, transparent wings, and the adult fly is colored between gray and yellow [2]. Males have a rounded abdomen and are smaller than females. The abdomen in the females is larger and pointed. The larvae is cylindrical, white and has mouthhooks that are used to masticate the tender parts of the new shoots [3]. The bermudagrass stem maggot got its name from its host preference for bermudagrass (Cynodon dactylon) and stargrass (Cynodon nlemfuensis) [6]. Atherigona reversura is native to Central and Southeast Asia [3]. This fly was accidentally introduced into Hawaii, and causes great damage in turfgrass [4]. In 2009 it was reported in California and in 2010 was reported in Georgia and southern Mexico [2, 3]. Without clear knowledge of its introduction, the bermudagrass stem maggot has rapidly spread across over the Southeast of United States causing significant yield loss in grazing and hay production systems [6, 8]
Little is known about the life cycle of A. reversura, nevertheless, it has been reported that the eggs are laid by the fly in the underside of the leaf in bermudagrass. After 2.5 days the larva emerge and move to the node where the stem emerges. The larva feed from the node causing the death of the leaf. After 1 to 3 days the feeding damage is evident, the larvae leave the stem, and move to the ground for pupation, where after 7 or 10 days the flies emerge. Adult flies can survive approximately 30 to 40 days producing many offspring during its adult life [3, 7]. In general all the bermudagrass cultivars have been susceptible to the stem maggot damage, but cultivars with high number of shoots, small shoot diameter and narrow leaves show higher preference by the fly [3, 8].
Currently the recommendations to suppress infestations in the crops are to harvest the grass to help break the life cycle and to apply pyrethroid insecticides after grass regrowth, approximately 7 to 10 days after cutting [3, 7 and 9]. Current research focuses on improving understanding of the behavior, biology and ecology of this insect pest.
REFERENCES 1. http://www.epa.gov/oppfead1/cb/csb_page/updates/2011/pyrethrins.html 2. Grzywacz, A., Pape, T., Hudson, W., Gomez, S. 2013. Morphology of immature stages of Atherigona reversura (Diptera: Muscidae), with notes on the recent invasion of North America. Journal of Natural History. 47:15-16, 1055-1067 http://dx.doi.org/10.1080/00222933.2012.742244 3. Hancock, D.W., Hudson, W., Baxter, L.L. and McCullers J.T. 2014. American Forage and Grassland Council’s Annual Meeting, January 13-14th, Memphis, TN. Hardy, D.E. 1976. Proceedings of the Hawaiian Entomological Society for 1974. Hawaiian Entomol. Soc. Proc., Honolulu, Hawaii, 1974. Hawaiian Entomol. Soc. 22(2) 4. Ikeda H, Oyamada M, Ando H, Kanai M, Fuji K. 1991. Varietal differences of Bermudagrass (Cynodon dactylon (L.) Pers.) in parasitic shoot ratio caused bermudagrass stem maggot (Atherigona reversura Villeneuve). J Japan Grassl Sci. 37:240 5. http://www.caes.uga.edu/Applications/ImpactStatements/index.cfm?referenceInterface=IMP ACT_STATEMENT&subInterface=detail_main&PK_ID=3278 6. http://www.caes.uga.edu/commodities/fieldcrops/forages/ga_cat_arc/2012/gc1207.pdf 7. http://msucares.com/crops/forages/newsletters/13/20130801.pdf 8. http://bay.ifas.ufl.edu/newsletters/2013/06/13/bermudagrass-stem-maggot-id-and- management/
CALVING SEASON ECONOMICS
Chris Prevatt RSA, Livestock and Forage Economist Range Cattle Research and Education Center, Ona, FL 2014 NFREC Beef/Forage Field Day, Marianna, Florida
Florida’s beef producers continue to look for ways to enhance the profitability of their cow-calf operations. Sometimes the most basic management practice can have a huge impact. The choice of a calving season is one of the most important management decisions a cow-calf producer makes. The calving season is a key driver for most of the other operations and production practices on a ranch. The calving season interacts with forage and feed availability and environmental stress at key times such as calving, re-breeding, and post-weaning recovery of body condition. The month to begin the calving season should include some consideration of economic, management and labor availability, forage and feed availability, animal nutritional requirements, and health considerations. If the primary objective of cattle producers is to make a profit, economic factors should always be weighed and included when making calving season decisions. The objective of this analysis was to compare the production numbers and economic returns of the four major calving seasons found in North Florida. The four calving seasons evaluated were fall calving (Oct. 1 – Dec. 31), winter calving (Dec. 15 – March 15), spring calving (March 1 – May 31), and year-round calving (Jan 1 – Dec. 31). Each calving season was analyzed in a costs and returns budget format to determine the level of net returns. The performance measurements used for this study were the average of measurements collected from a small group of UF/IFAS Extension Specialists and County Agents. Fall and winter calving is an option in regions where fall and winter weather conditions are favorable for calf-growth and cow-rebreeding. Fall and winter calving herds generally must rely on harvested and purchased feedstuffs during the winter months. Calving during these time periods mean that the nutritional requirements of cows are 25% to 30% higher (during lactation) at a time when most forage resources in North Florida are dormant and low in protein and energy. Thus, supplemental feedstuffs and/or winter annuals containing energy and protein must be fed. The primary challenge for fall and winter calving herds is the higher cost of winter feeding. Therefore, the higher feed costs associated with fall and winter calving cows may offset any advantages of stronger prices during their traditional marketing periods if they aren’t managed properly. Spring calving matches the increased nutritional needs of lactating cows with higher quality forage. The nutrient contents of spring forages are usually higher in energy and protein. Calving during the spring should ensure that the additional nutrients demanded by lactating cows are provided by growing pasture. Harvested and purchased feedstuffs are significantly reduced in spring calving herds with little or no supplementation needed during lactation. The majority of cows in the U.S. calve during the spring. Their calves are usually weaned and marketed during the fall months. The primary reason spring born calves are sold during this traditional marketing time period is so they do not have to be held over during the winter months and fed/grazed on higher cost feedstuffs. Unfortunately, spring-born calves typically enter the market when supply is at its highest and prices are at the lowest. For year-round calving systems, producers are faced with two major obstacles which include 1) providing adequate nutrition to animals in different states of production (dry, gestating, and lactating) and 2) performing best management practices (castrating, deworming, vaccinating, pregnancy checks, breeding soundness evaluation, etc.) at the appropriate time to achieve the desired results. Thus, implementing management practices and using feed, supplement, and pasture resources efficiently becomes nearly impossible. These resources will be used efficiency by some cows and wasted by others that may not need them. Additionally, not meeting a cow’s nutritional requirements will negatively affect their performance and profitability. The less fertile and less productive cows are more difficult to be identified in year-round calving systems resulting in higher costs of production per unit of output (cost per pound of calf production). The timing of weaning of most southern calves is typically done due to the weather in the fall (when warm-season grasses slow or stop growing) regardless of the weight or age of the calves. For this analysis, fall born calves were marketed July 15th, winter born calves were marketed September 1st, spring born calves were marketed on October 15th, and year-round born calves were marketed throughout the year (price based on average annual price). Calving Season Results Table 1 describes the summary of the estimated performance, costs, and returns over costs for the four calving season scenarios for North Florida during 2014 that were examined in this analysis. The study results revealed that the combination of costs, performance, and market prices are necessary to determine which scenario resulted in the highest returns over total costs. In essence, no single variable (highest prices, highest revenue, lowest costs, etc.) determine the optimal outcome for this study. In addition, these results are very sensitive to the variables used and different outcomes may be realized with slightly different inputs, input prices, management practices, and market prices. Each individual must evaluate their situation using their numbers to make this important decision for their cattle operation.
Table 1. Summary of Estimated Performance, Costs, and Returns Over Costs for Four Calving Season Scenarios, North Florida, 2014. Fall Winter Spring Year-Round Item Calving Calving Calving Calving
Weaning percent 85% 85% 85% 75% Average calf weight 520 475 415 405 Age of calf @ weaning, days 240 210 180 180 Averge calf price, $/cwt. 2.61 2.71 2.52 2.61 Cull animal rate, % 15% 15% 15% 15%
Returns per brood cow, $/hd $1,318.62 $1,259.16 $1,052.17 $959.79
Cost per brood cow, $/hd $1,216.89 $1,108.34 $982.97 $932.69
Returns over costs per brood cow, $/hd $101.73 $150.83 $69.20 $25.10
Fall calving had a 90% calving rate and weaned calves from 85% of their herd. Fall-born calves were marketed July 15th (240 days old) at an average weight of 520 lbs. The fall-born calves brought $261/cwt. producing revenue of $1,357. The gross returns per cow-unit were $1,318.62. Feed costs and costs per cow per unit for fall calving totaled $371.36 and $1,216.89, respectively. Fall calving generated returns over total costs per cow of $101.73. The spring calving herd resulted in lower costs from feeding less purchased and harvested feeds than did the fall and winter calving seasons. Thus, spring calving will generally minimize inputs, production costs, and management and labor. The year-round calving scenario resulted in the lowest performance, lowest costs, lowest revenues, and lowest net returns of the four scenarios. The year-round calving scenario is common on many southern cow-calf operations. It usually represents lower levels of input, management, and net returns. Based on the assumptions made in this analysis and if calves are to be sold at their traditional marketing date as presented in this analysis, the winter calving herd returned more dollars over total costs per cow. Winter calving cow-calf operations usually incur less production costs compared with fall calving herds which can result in lower costs per hundredweight of calf production. Summary There are many factors to consider when selecting a calving season. Economics should always play a role in the management decisions producers are faced with. However, factors such as resources, labor, and animal health should also be considered. Each operation must make this decision based on their resources, goals, and objectives. There is not one calving season which fits every Florida farm. A unique set of conditions exists on each cattle farm across Florida which will determine the optimal calving and breeding seasons. It is vital that cow-calf producers carefully weigh the advantages and disadvantages of each calving season for their operation. Producers are encouraged to visit with other producers who are practicing the calving season they are interested in adopting and learn about their inputs, costs, performance, and market prices. A calving season which maintains breeding efficiency and produces rapid weight gains while maximizing the use of standing forage is likely to be the most profitable. A successful calving season is the result of good planning and hard work! Start planning for 2015 and good luck.
2014 Cow-Calf Calving Season Budgets The following costs and returns budgets for the four calving season scenarios will provide the detailed information used in this analysis. This information does not represent any individual or the average cattle producer. This is simply the assumptions used in this analysis. The spreadsheet is available for anyone to use to compare their individual situation.
North Florida Cow-Calf Cow-Calf Enterprise Budget, Fall Calving, Market @ 240 Days, July 15, 2014
A Returns Per Cow Per Year A1Weaning percent 85% A 2 Average calf weight, lbs./calf 520 A 3 Total calf weight, lbs 13,260 A 4 Average calf weight, lbs./cow-unit 442 A 5 Averge calf price, $/lb. $2.61 A 6 Total cull cow weight, lbs. 4,950 A 7 Average cull cow weight, lbs./cow 1,100 A 8 Average cull cow weight, lbs./cow-unit 165 A 9 Average cull cow price, $/lb. $1.00 A 10 Gross returns, total $ $39,559 A 11 Average calf return, $/cow-unit $1,153.62 A 12 Average cull cow return, $/cow-unit $165.00 A 13 Gross returns, $ per cow-unit $1,318.62 Percent of B Costs Per Cow Per Year $/Cow-Unit Total Cost B1Pasture $100.00 8% B 2 Purchased feed $371.36 31% B 3 Machinery & equipment $145.83 12% B 4 Animal health $38.11 3% B 5 Buildings/Improvements/Facilities-DIRT $38.75 3% B 6 Buildings/Improvements/Facilities-Interest $25.00 2% B7Management $0.00 0% B8Labor $0.00 0% B9Custom hire $12.00 1% B 10 Farm records $9.00 1% B 11 Professional fees $13.33 1% B 12 Utilities $12.17 1% B 13 Marketing fees $56.04 5% B 14 Supplies $12.17 1% B 15 Replacement heifer capital cost $300.00 25% B 16 Annual bull cost depreciation $12.50 1% B 17 Interest on breeding stock capital $33.83 3% B 18 Insurance on breeding stock $4.23 0% B 19 Interest on operating cost1 $32.57 3% B 20 Cost per cow per year $1,216.89 100%
C Returns Over Total Costs Per Cow Per Year $101.73
D Average Feeder Calf Price Needed Per Cwt. D 1 To Cover Feed Costs, $/cwt. $106.64 D 2 To Cover Total Costs, $/cwt. $237.98
E Asset Turnover Ratio (A/Investment)2 56%
FNet Return on Investment 8.3% ((C + B17 + B28+ B30)/Investment)3
1Operating interest was charged on one-half of the cost per cow per year (Cow-calf budget, B20). 2The asset turnover ratio measures the amount of sales that are generated from each dollar of assets. Asset Turnover Ratio is gross returns (A13) divided by the investment (value of the breeding stock/cow unit, Cow-calf data input, M14, value of equipment/cow-unit, Cow-calf data input, P75, and value of buildings, improvements, and facilities/cow-unit, Cow-calf data input, P110). 3The net re turn on inve stment is the pe rcentage re turn on your investme nt. Net return on investment is the sum of returns over total costs (Cow-calf budget, C) plus interest on building/improvements/facilities (Cow-calf budget, B6) plus interest on breeding stock (Cow-calf budget, B17) plus interest on operating capital (Cow-calf budget, B19) divided by the investment. North Florida Cow-Calf Cow-Calf Enterprise Budget, Winter Calving, Market @ 210 Days, Sept. 1, 2014
A Returns Per Cow Per Year A 1 Weaning percent 85% A 2 Average calf weight, lbs./calf 475 A 3 Total calf weight, lbs 12,113 A 4 Average calf weight, lbs./cow-unit 404 A 5 Averge calf price, $/lb. $2.71 A 6 Total cull cow weight, lbs. 4,950 A 7 Average cull cow weight, lbs./cow 1,100 A 8 Average cull cow weight, lbs./cow-unit 165 A 9 Average cull cow price, $/lb. $1.00 A 10 Gross returns, total $ $37,775 A 11 Average calf return, $/cow-unit $1,094.16 A 12 Average cull cow return, $/cow-unit $165.00 A 13 Gross returns, $ per cow-unit $1,259.16 Percent of B Costs Per Cow Per Year $/Cow-Unit Total Cost B1Pasture $100.00 9% B2Purchased feed $278.24 25% B 3 Machinery & equipment $135.83 12% B4Animal health $38.11 3% B 5 Buildings/Improvements/Facilities-DIRT $38.75 3% B 6 Buildings/Improvements/Facilities-Interest $25.00 2% B 7 Management $0.00 0% B8Labor $0.00 0% B9Custom hire $12.00 1% B10Farm records $9.00 1% B 11 Professional fees $13.33 1% B 12 Utilities $12.17 1% B 13 Marketing fees $53.51 5% B 14 Supplies $12.17 1% B 15 Replacement heifer capital cost $300.00 27% B 16 Annual bull cost depreciation $12.50 1% B 17 Interest on breeding stock capital $33.83 3% B 18 Insurance on breeding stock $4.23 0% B 19 Interest on operating cost1 $29.66 3% B 20 Cost per cow per year $1,108.34 100%
C Returns Over Total Costs Per Cow Per Year $150.83
D Average Feeder Calf Price Needed Per Cwt. D 1 To Cover Feed Costs, $/cwt. $93.68 D 2 To Cover Total Costs, $/cwt. $233.64
E Asset Turnover Ratio (A/Investment)2 54%
F Net Return on Investment 10.3% ((C + B17 + B28+ B30)/Investment)3
1Operating interest was charged on one-half of the cost per cow per year (Cow-calf budget, B20). 2The asset turnover ratio measures the amount of sales that are generated from each dollar of assets. Asset Turnover Ratio is gross returns (A13) divided by the investment (value of the breeding stock/cow unit, Cow-calf data input, M14, value of equipment/cow-unit, Cow-calf data input, P75, and value of buildings, improvements, and facilities/cow-unit, Cow-calf data input, P110). 3The net return on investment is the percentage return on your investment. Net return on investment is the sum of returns over total costs (Cow-calf budget, C) plus interest on building/improvements/facilities (Cow-calf budget, B6) plus interest on breeding stock (Cow-calf budget, B17) plus interest on operating capital (Cow-calf budget, B19) divided by the investment. North Florida Cow-Calf Cow-Calf Enterprise Budget, Spring Calving, Market @ 180 Days, Oct. 15, 2014
A Returns Per Cow Per Year A 1 Weaning percent 85% A 2 Average calf weight, lbs./calf 415 A 3 Total calf weight, lbs 10,583 A 4 Average calf weight, lbs./cow-unit 353 A 5 Averge calf price, $/lb. $2.52 A 6 Total cull cow weight, lbs. 4,950 A 7 Average cull cow weight, lbs./cow 1,100 A 8 Average cull cow weight, lbs./cow-unit 165 A 9 Average cull cow price, $/lb. $1.00 A 10 Gross returns, total $ $31,565 A 11 Average calf return, $/cow-unit $887.17 A 12 Average cull cow return, $/cow-unit $165.00 A 13 Gross returns, $ per cow-unit $1,052.17 Percent of B Costs Per Cow Per Year $/Cow-Unit Total Cost B1Pasture $100.00 10% B 2 Purchased feed $160.03 16% B 3 Machinery & equipment $135.83 14% B 4 Animal health $38.11 4% B 5 Buildings/Improvements/Facilities-DIRT $43.75 4% B 6 Buildings/Improvements/Facilities-Interest $25.00 3% B 7 Management $0.00 0% B8Labor $0.00 0% B9Custom hire $12.00 1% B 10 Farm records $9.00 1% B 11 Professional fees $13.33 1% B 12 Utilities $12.17 1% B 13 Marketing fees $44.72 5% B 14 Supplies $12.17 1% B 15 Replacement heifer capital cost $300.00 31% B 16 Annual bull cost depreciation $12.50 1% B 17 Interest on breeding stock capital $33.83 3% B 18 Insurance on breeding stock $4.23 0% B 19 Interest on operating cost1 $26.31 3% B 20 Cost per cow per year $982.97 100%
C Returns Over Total Costs Per Cow Per Year $69.20
D Average Feeder Calf Price Needed Per Cwt. D 1 To Cover Feed Costs, $/cwt. $73.71 D 2 To Cover Total Costs, $/cwt. $231.88
E Asset Turnover Ratio (A/Investment)2 45%
F Net Return on Investment 6.6% ((C + B17 + B28+ B30)/Investment)3
1Operating interest was charged on one-half of the cost per cow per year (Cow-calf budget, B20). 2The asset turnover ratio measures the amount of sales that are generated from each dollar of assets. Asset Turnover Ratio is gross returns (A13) divided by the investment (value of the breeding stock/cow unit, Cow-calf data input, M14, value of equipment/cow-unit, Cow-calf data input, P75, and value of buildings, improvements, and facilities/cow-unit, Cow-calf data input, P110). 3The net return on investment is the percentage return on your investment. Net return on investment is the sum of returns over total costs (Cow-calf budget, C) plus interest on building/improvements/facilities (Cow-calf budget, B6) plus interest on breeding stock (Cow-calf budget, B17) plus interest on operating capital (Cow-calf budget, B19) divided by the investment. North Florida Cow-Calf Cow-Calf Enterprise Budget, Year-Round Calving, Market @ 180 Days, July 15, 2014
A Returns Per Cow Per Year A1Weaning percent 75% A 2 Average calf weight, lbs./calf 405 A 3 Total calf weight, lbs 9,113 A 4 Average calf weight, lbs./cow-unit 304 A 5 Averge calf price, $/lb. $2.61 A 6 Total cull cow weight, lbs. 4,950 A 7 Average cull cow weight, lbs./cow 1,100 A 8 Average cull cow weight, lbs./cow-unit 165 A 9 Average cull cow price, $/lb. $1.00 A 10 Gross returns, total $ $28,734 A 11 Average calf return, $/cow-unit $792.79 A 12 Average cull cow return, $/cow-unit $165.00 A 13 Gross returns, $ per cow-unit $957.79 Percent of B Costs Per Cow Per Year $/Cow-Unit Total Cost B1Pasture $100.00 11% B 2 Purchased feed $118.02 13% B 3 Machinery & equipment $135.83 15% B4Animal health $38.11 4% B 5 Buildings/Improvements/Facilities-DIRT $38.75 4% B 6 Buildings/Improvements/Facilities-Interest $25.00 3% B 7 Management $0.00 0% B8Labor $0.00 0% B9Custom hire $12.00 1% B 10 Farm records $9.00 1% B 11 Professional fees $13.33 1% B 12 Utilities $12.17 1% B 13 Marketing fees $40.71 4% B 14 Supplies $12.17 1% B 15 Replacement heifer capital cost $300.00 32% B 16 Annual bull cost depreciation $14.58 2% B 17 Interest on breeding stock capital $33.83 4% B 18 Insurance on breeding stock $4.23 0% B 19 Interest on operating cost1 $24.96 3% B 20 Cost per cow per year $932.69 100%
C Returns Over Total Costs Per Cow Per Year $25.10
D Average Feeder Calf Price Needed Per Cwt. D 1 To Cover Feed Costs, $/cwt. $71.77 D 2 To Cover Total Costs, $/cwt. $252.74
E Asset Turnover Ratio (A/Investment)2 41%
F Net Return on Investment 4.7% ((C + B17 + B28+ B30)/Investment)3
1Operating interest was charged on one-half of the cost per cow per year (Cow-calf budget, B20). 2The asset turnover ratio measures the amount of sales that are generated from each dollar of assets. Asset Turnover Ratio is gross returns (A13) divided by the investment (value of the breeding stock/cow unit, Cow-calf data input, M14, value of equipment/cow-unit, Cow-calf data input, P75, and value of buildings, improvements, and facilities/cow-unit, Cow-calf data input, P110). 3The net return on investment is the percentage return on your investment. Net return on investment is the sum of returns over total costs (Cow-calf budget, C) plus interest on building/improvements/facilities (Cow-calf budget, B6) plus interest on breeding stock (Cow-calf budget, B17) plus interest on operating capital (Cow-calf budget, B19) divided by the investment. Economic Considerations for Using Hay or Haylage
Mark Mauldin, UF Extension County Agent, Washington County
When determining how conserved forages – hay and/or haylage, fit into a supplemental feeding program the economic ramifications of the decision should be considered closely. The economic feasibility of conserving forages varies from year to year as input costs and the costs of alternative feedstuffs vary. When conserving forages is a viable option it is important to determine if it is more efficient to utilize hay or haylage; the following is a brief comparison of hay and haylage. Production Production practices associated with cured hay and haylage, also referred to as balage or round bale silage, are virtually identical until the growing forage has been cut; from that point forward the two products are handled very differently. When producing cured hay the forage is cut and allowed to dry to below 20% moisture. The dried forage is then baled and stored. Haylage is baled at much higher moisture content, 40-60% moisture. An oxygen excluding wrap is then applied to the high moisture bales. Inside the wrap the forage ensiles and is preserved. The main differences in the production of hay and haylage are the necessity of extended drying time for hay and wrapping/airtight storage of haylage. Each of these factors presents certain challenges that a producer must negotiate. Under favorable weather conditions, hay takes three to four days to cure. If hay is rained on during the curing process there can be substantial loss of nutritional value. Considering this, producers plan most hay cuttings based solely on expected weather conditions. Ideally, the decision to harvest forage would be based on stage of maturity given its effects on the quality of the hay produced (Figure 1 and 2).
Figure 1. Effects of maturity on forage protein (Chambliss, et al. 1998)
Figure 2. Effect of maturity on forage TDN (Chambliss, et al. 1998) Producing haylage provides a solution to this problem. Because haylage does not require extended drying time the weather is much less of a concern. The decision to harvest forage for haylage can be based on a production schedule that maximizes total season-long production without sacrificing quality to rain or overly mature forage. In a study, when compared to cured hay production, two additional cuttings were made during the summer growing season utilizing a system that included haylage. On 25 acres, the two additional cuttings accounted for 109,985 more pounds of conserved dry matter (Hersom et al. 2011). An additional weather related advantage of haylage comes in the cooler months. Cool season forages (small grains, clovers, ryegrass, etc.) can be some of the highest quality forages produced in Florida. Conserving these forages as cured hay can be difficult because cooler soil and air temperatures greatly slow the drying process. If small grains are harvested during the milk or dough stage they can be particularly hard to dry due to the high moisture content inside the forming grain. Conserving these forages as haylage eliminates the aforementioned problems since the need for drying is effectively eliminated. While producing haylage does provide some advantages it is not without its own set of challenges. The largest challenge associated with haylage production is cost. Haylage production has all of the costs of cured hay production, with the exception of the fuel cost associated with tedding and, in some cases, raking hay, plus the additional expense of wrapping the bales. Wrapping expense comes in three main forms; 1) cost of wrapping material 2) wrapping equipment expense 3) additional time or labor costs associated with wrapping bales. Haylage production is more expensive than hay production - attempting to quantify exactly how much more expensive is difficult since that figure will vary substantially from one operation to another. There is tremendous variation in the price of wrapping equipment, depending on brand and model. The additional cost, on a per bale basis, is largely determined by the number of bales wrapped. As the number of bales wrapped increases the additional cost per bale decreases. Also, the cost of wrap is subject to change with market conditions. Feed Value Feed value of the final product is a major factor when determining the economic viability of a conserved forage system. When comparing hay and haylage, there are considerable differences in the feed values of the products which should be taken into account. The largest difference between the two products is the moisture content. Nutritional requirements of cattle are generally discussed in terms of dry matter intake (DMI), meaning feed values are determined based on the dry matter content of the given feedstuff. The water component of the feedstuff is not considered because it is generally assumed that cattle will have free access to water. Haylage has a significantly lower dry matter content than hay. As dry matter content decreases the nutrient density of the feedstuff generally decreases. High moisture content in a feedstuff effectively dilutes the nutrients requiring the animal to consume more total pounds of feed to take in the same amount of nutrients. More directly, it takes considerably more haylage to meet an animal’s nutritional requirements than it would hay – assuming that the nutritional content of the forage was the same when it was harvested. The feed value of any conserved forage is based on the nutrient content of the forage at harvest time. From the time forage is cut its nutrient content will only go down. This can be of particular concern when producing cured hay; if forage is cut for hay and then rained on significant reduction in quality can occur before it is dry enough to bale. Since haylage is baled at much higher moisture content this potential reduction in quality is not an issue. It should be noted the ensiling process associated with haylage production does not increase the quality of the forage. At best, the quality of the haylage will equal that of the forage when it was harvested. The management of the forage prior to harvest has a much more significant effect on the quality of the feed produced than whether it was conserved as hay or haylage. Feeding and Storage Feeding practices and proper storage are important economic considerations when looking at hay or haylage. Substantial losses can occur if either product is fed or stored improperly. The key to eliminating storage losses with haylage relates back to the baling and wrapping processes. If bales are sufficiently tight – to prevent excess oxygen inside the bale, and properly wrapped – to effectively exclude oxygen, storage losses with haylage will be minimal, assuming the integrity of the wrap is not compromised. If the wrap is damaged it should be repaired immediately. Oxygen infiltration will rapidly lead to mold growth and spoilage. Along these same lines, once the wrapping of a line of haylage is opened it entire line should be fed in a timely manner to prevent spoilage. Storing cured hay is a major economic consideration; if baled hay is left unprotected – uncovered and touching the ground, dry matter losses of more than 50% are not uncommon. As protection from moisture increases dry matter losses decrease. There is generally some cost associated with preventing/reducing storage losses (barns, tarps, gravel beds, etc.). This cost should be considered when evaluating the economic viability of hay. If no measures are taken to protect the hay then additional hay will be required to compensate for the dry matter loss. Feeding waste/loss associated with hay and haylage are largely dependent on the feeding technique(s) used. Both products should be fed in as small amounts as feasible – the more feed cattle have access to at one time the more likely they are to waste or soil it before it is consumed. Additionally, both products should be fed in some type of device that prevents the cattle from standing in the feed while eating (hay rings, trailers, etc.). All other factors being equal, cattle tend to find haylage more palatable than cured hay, especially poor quality hay. This tends to help lessen feeding waste/losses associated with haylage because cattle consume it more aggressively leaving less opportunity for waste to occur. Conclusion Hay and haylage can both be economically viable; hay and haylage can both be poor economic decisions. When weather allows for timely harvest and drying, hay tends to be more economical because there is much less wrapping expense and it yields a more nutrient dense final product. However, when hay quantity or quality is negatively affected by the weather haylage can quickly become the more economical option. Because hay and haylage are the most efficient in different situations, systems that utilize both and allow the two methods to complement each other are often very effective. Hay, haylage, or a combination – all are dependent on good forage management. It is never cost effective to conserve poor quality forage regardless of the technique used. References Chambliss, C.G., M.B. Adjei, J. Arthington, W.E. Kunkle, and R.P. Cromwell. 1998. “Hay Production in Florida.” EDIS Document SS-AGR-70, 6pp, Univ. of Florida, Gainesville.
Hersom, M., T. Thrift, and J. Yelich. 2011. “Comparison of Hay or Round Bale Silage as a Means to Conserve Forage.” EDIS Document AN266, 6pp, Univ. of Florida, Gainesville.
Hersom, M. and W.E. Kunkle. 2003. “Harvesting, Storing, and Feeding Forages as Round Bale Silage.” EDIS Document AN145, 7pp, Univ. of Florida, Gainesville.
Selecting a bull for the cowherd
G. Cliff Lamb
University of Florida, North Florida Research and Education Center, Marianna, FL
Introduction
Purchasing a bull for the cowherd has tremendous long-lasting impacts on cow-calf operations. Generally, producers will frequently purchase bulls based on price and will pay for the cheapest bull. Often this bull ultimately becomes the most expensive bull that the producer could have purchased. If replacement heifers are retained in the herd, 80-90% of the genetic change in a herd will be made by the bull's genetic makeup. Therefore, making an effort to in selecting the right bull is one of the most important decisions a producer can make. In addition, good management of the bull after he arrives at the farm or ranch is also very important. The best genetic package is of little value unless the bull is managed to serve a large number of cows in the time frame you want him to be productive. There are many factors to consider when trying to identify the best bull for an operation and these will be addressed below.
Considerations for Selecting Bulls
There are a number of considerations when selecting a bull to purchase. A producer should consider each of these individual items to define the best bull for their operation.
1. Structural Soundness - Structural soundness and conformation is an important factor because the bull must be physically able to service cows during breeding. Therefore sound feet and legs, particularly hind legs, are critical for a long service life of the bull.
2. Performance Records/Pedigree - If the bull is purchased through a bull test sale, how well did he perform? What is the performance or record of the bull's siblings or half-siblings? This information can be gathered by examining his pedigree. In addition, bulls at the Florida Bull Test (http://nfrec.ifas.ufl.edu/fl_bull_test/index.shtml ) have all of this data. One interesting aspect of the Florida Bull Test is the ability to obtain individual feed efficiency on every bull. Using residual feed intake, or RFI, as a measure of feed efficiency producers can identify bulls that may be more feed efficient than other bulls. For example (Table 1) in the current test using preliminary on test data for the first 28 days of the test, I have identified two bulls of the same breed that started the test at the same weight. After 28 days bull 1248 had an average daily gain (ADG) of 2.50 lb/day compared to bull 1252 who had an ADG of 2.11 lb/day. More importantly bull 1248 converted feed more efficiently with a feed conversion ratio of 7.19 compared to 11.80 lb of feed per lb of gain. When looking at RFI bull 1248 had an RFI of -2.80 and bull 1252 had an RFI of 4.77. Essentially this means that bull 1248 consumed 2.80 lb/day less feed than expected for his 2.50 lb/day ADG, meaning that he was quite efficient. Conversely, bull 1252 consumed 4.77 lb/day more than expected for his 2.11 lb/day ADG, meaning that he was inefficient.
To keep this in perspective, if these bulls continue to have similar consumption and efficiencies throughout the year bull 1248 would consume 6,559 lb of feed in a year compared to bull 1252 who would consume 9,078 lb feed per year with less gain that would be achieved with bull 1248. It is hard to imagine that producers would see the financial benefit of a single bull consuming 2,519 lb feed less in a year than another bull. Consider the impact of this simple selecting selection on the entire operation.
Table 1. Preliminary feed intake and performance data of two bulls in the 2014-2015 Florida Bull Test that initiated the test at the same weight Initial 28-day 28-day 28-day 28 d RFI, Bull ID weight, lb weight, lb ADG, lb/d DMI, lb/d F:G lbs/d
1248 975 1045 2.50 17.97 7.19 -2.80
1252 976 1035 2.11 24.87 11.80 4.77
3. Expected Progeny Differences and Indexes - Expected Progeny Differences (EPD) predicts the differences expected in performance of future progeny of two or more sires of the same breed when mated to animals of the same genetic potential. Indexes are multi-trait selection indexes, expressed in dollars per head, to assist beef producers by adding simplicity to genetic selection decisions. Many cattle producers routinely use EPDs to select sires to meet their production goals. Below is a version of the pedigree, EPD and indexes used in the Florida Bull Test (Figure 1). An example of a typical Appendix A provides a definition of various EPD's and indexes that are common and also used in the Florida Bull Test.
Figure 1. An example of the Florida Bull Test pedigree, EPD, and index sheet provided for each bull in the sale. 4. Acclimation to the Environment - Find a bull that is acclimated to your ranch's climate and management conditions. The lack of adaptation leads to poor performance of bulls both physically and during the breeding season.
5. Passing a Breeding Soundness Examination - A BSE is a quick and relativity inexpensive way of assessing a bulls fertility potential. Bulls should be examined at least 60 days prior to the beginning of the breeding season. This allows for re-testing and replacement of bulls failing the examination. All purchased bulls should have passed a BSE prior to sale. ABSE consists of four basic steps: 1) visual assessment of the feet, legs, eyes, teeth and external genitalia; 2) Palpation of the accessory sex glands (prostrate and seminal vesicles); 3) Measurement of the scrotum as well as palpation of the testis and epididymis; and; 4) Collection and microscopic evaluation of a semen sample. If the bull scores very low or fails the BSE, the bull should be re-checked in 60 to 80 days. A number of issues could cause a bull to fail a BSE including injury to the testes or illness which can cause abnormal or low sperm formation.
5. Other Selection Considerations – 1) Temperament is also an important trait because it can be a highly heritable trait. 2) Consider the cow's mature bodyweight and frame size and the desired calf characteristics when selecting a bull; 3) Breed type is an important consideration for the bull and the resulting mating with the cow herd. One way to produce heavier calves with improved carcass traits is through hybrid vigor.
Conclusion
When cattle producers purchase and turn the bull out, they have made one of the largest decisions dictating carcass merit for the subsequent calves. Cattle producers can pursue genetic change for numerous characteristics by selecting and utilizing the appropriate genetic sources. Therefore, selecting and implementing a genetic program with specific goals is important. All management processes performed after the genetic choices are done to optimize the genetic potential of the resulting calf.
APPENDIX A - DEFINITION OF EPD AND INDEX TERMS
BW Birth Weight EPD - expressed in pounds, is a predictor of a sire's ability to transmit birth weight to his progeny compared to that of other sires.
WW Weaning Weight EPD - expressed in pounds, is a predictor of a sire's ability to transmit weaning growth to his progeny compared to that of other sires.
YW Yearling Weight EPD - expressed in pounds, is a predictor of a sire's ability to transmit yearling growth to his progeny compared to that of other sires.
M Maternal Milk EPD - is a predictor of a sire's genetic merit for milk and mothering ability as expressed in his daughters compared to daughters of other sires. In other words, it is that part of a calf's weaning weight attributed to milk and mothering ability.
Scrotal Scrotal Circumference EPD - expressed in centimeters, is a predictor of the difference in transmitting ability for scrotal size compared to that of other sires.
IMF Marbling EPD - expressed as a fraction of the difference in USDA marbling score of a sire's progeny compared to progeny of other sires.
REA Ribeye Area EPD - expressed in square inches, is a predictor of the difference in ribeye area of a sire's progeny compared to progeny of other sires.
BF Fat Thickness EPD - expressed in inches, is a predictor of the differences in external fat thickness at the 12th rib (as measured between the 12th and 13th ribs) of a sire's progeny compared to progeny of other sires.
ADG Average Daily Gain – average daily gain on test during the 112 day FL Bull Test
WDA Weight per Day of Age – Weight per day of age from birth until the end of the final weight of the FL Bull Test
$VALUE INDEXES $Value indexes are multi-trait selection indexes, expressed in dollars per head, to assist beef producers by adding simplicity to genetic selection decisions. The $Value is an estimate of how future progeny of each sire are expected to perform, on average, compared to progeny of other sires in the database if the sires were randomly mated to cows and if calves were exposed to the same environment.
$API All-Purpose Index - is the expected average performance of progeny of Simmental bulls used on the entire Angus cowherd, with a portion of the daughters being retained for breeding and the remaining progeny being put on feed and sold grade and yield.
$TI/TSI Terminal index - is the expected average profit per carcass of progeny of bulls mated to British-cross cows, with all offspring placed in the feedlot and sold grade and yield. It includes growth and carcass information only.
$BMI This is an index to maximize profit for commercial cow-calf producers who use Hereford bulls in rotational crossbreeding programs on Angus-based cows. Retained ownership of calves through the feedlot phase of production is maintained and the cattle are to be marketed on a CHB pricing grid.
$CHB This is a terminal sire index, where Hereford bulls are used on British-cross cows and all offspring are sold as fed cattle on a CHB pricing grid. There is no emphasis on milk or fertility since all cattle will be terminal. This index promotes growth and carcass.
$W Weaned Calf Value - an index value expressed in dollars per head, is the expected average difference in future progeny performance for preweaning merit. $W includes both revenue and cost adjustments associated with differences in birth weight, weaning direct growth, maternal milk, and mature cow size.
$F Feedlot Value - an index value expressed in dollars per head, is the expected average difference in future progeny performance for postweaning merit compared to progeny of other sires.
$B Beef Value - an index value expressed in dollars per head, is the expected average difference in future progeny performance for postweaning and carcass value compared to progeny of other sires.
FEED EFFICIENCY DATA:
Feed Efficiency Rank Ranking from most efficient (low ranking) to least efficient (high ranking) compared to all bulls in the FL Bull Test.
Intake The pounds (on a dry matter basis) consumed on a daily basis during the 56 day feed efficiency portion of the test.
F:G The pounds of feed consumed per pound of gain per bull during the 56 d feed efficiency portion of the test.
RFI The residual feed intake was calculated as the difference between actual average daily feed intake and expected daily feed intake for each bull based on their average daily gain on test during the 56 d feed efficiency portion of the test. This value was used as the criteria for Feed Efficiency Rank. Bulls with a low RFI are more efficiency than bulls with a high RFI.
Adjusted Because ultrasound measurements are taken on a single day bulls vary in age. Therefore, measurements are adjusted to be on an equal age basis so that bulls may be compared with each other. When comparing ultrasound data between bulls, adjusted measurements are more reliable.