Beef Cattle Handbook BCH-1000 Product of Extension Beef Cattle Resource Committee Adapted from Beef Improvement Federation Beef Performance Glossary John Hough, Amercian Hereford Association David Notter, Virginia Polytechnic Institute and State University Accuracy (of selection) - Correlation between an ani- Improvement Association representative, or area office mal’s unknown actual breeding value and a calculated esti- of USDA meat grading service for information. mated breeding value (or expected progeny difference). Beef Improvement Federation (BIF) - A federation of Average daily gain (ADG) - Measurement of an ani- organizations, businesses, and individuals interested or mal's daily body-weight change. involved in performance evaluation of beef cattle. The purposes of BIF are to bring about uniformity of proce- Adjusted weaning weight (WW) - An unshrunk, off- dures, development of programs, cooperation among the-cow weight adjusted to 205 days of age and to a interested entities, education of its members, and the mature dam age equivalence. ultimate of user performance evaluation methods. It also builds the confidence of the beef industry in the princi- Adjusted yearling weight (YW) - An unshrunk weight ples and potentials of performance testing. adjusted to either 365, 452, or 550 days of age. Birth weight (BW) - The weight of a calf taken within Alleles - Alternate forms of genes. Because genes occur 24 hours after birth. Heavy birth weights tend to be cor- in pairs in body cells, one gene of a pair may have one related with calving problems, but the conformation of effect and another gene of that same pair (allele) may the calf and the cow are contributing factors. have a different effect on the same trait. Body condition score - A score on a scale of 1 to 9, Artificial insemination (AI) - The technique of placing reflecting the amount of fat reserves in a cow’s body, semen from the male into the reproductive tract of the where 1 = very thin and 9 = extremely fat. female by means other than natural service. Bos indicus - These are the Zebu (humped) cattle Backcross - The mating of a two-breed crossbred off- including the Brahman breed in the United States. spring back to one of its parental breeds. Example: A Hereford-Angus cross cow bred back to an Angus bull. Bos taurus - Includes most cattle found in the United States, including their European ancestors. Beef carcass data service - A program whereby pro- ducers, for a fee, can receive carcass evaluation data on Breed - Animals which have a common origin and com- their cattle by using a special “carcass data” eartag for mon characteristics that distinguish them from other their animals to be processed. See your county exten- groups of animals within that same species. sion director, breed representative, Beef Cattle BCH-1000 1 Breeding program goals - The objective or “direction” Chromosome - Chromosomes are long DNA molecules of breeders' selection programs. Goals are basic deci- on which genes (the basic genetic codes) are located. sions breeders must make to give “direction” to their Domestic cattle have 30 pairs of chromosomes. breeding program. Goals should vary among breeders due to relative genetic merit of their cattle, their Closed herd - A herd in which no outside breeding resources, and their markets. stock (cattle) are introduced. Breeding soundness examination - Inspection of a Collateral relatives - Relatives of an individual that are bull involving evaluation of physical conformation and not its ancestors or descendants. Brothers and sisters soundness through genital palpation, scrotal circumfer- are an example of collateral relatives. ence, and testing semen for motility and morphology. Compensatory gain - Gain from cattle that have been Breeding value - Value of an animal as a parent. The nutritionally deprived for part or all of their life. Once fed working definition is, twice the difference between a very feedlot diets they compensate for the earlier restriction large number of progeny and the population average, of feed by gaining very rapidly. when individuals are mated at random within the popu- lation, and all progeny are managed alike. The difference Conformation - The shape and arrangement of the dif- is doubled because only one gene of each pair is trans- ferent body parts of an animal. mitted from a parent to each progeny. Congenital - Acquired during prenatal life. Condition British breeds - Breeds of cattle such as Angus, exists at or dates from birth. Often used in the context of Hereford, and Shorthorn originating in Great Britain. congenital (birth) defects. Caesarean section - A process where the calf is Contemporary breed type group - A group of cattle removed from the cow during parturition by making a that are of the similar breed type, sex, and age, and have large incision in the right side of the cow just above the been raised in the same management group (same loca- flank. tion on the same feed and pasture). Contemporary groups should include as many cattle as can be accurate- Calving difficulty (Dystocia) - Abnormal or difficult ly compared. labor, causing difficulty in delivering the fetus and/or pla- centa. Correlation - A measure of how two traits vary togeth- er. A correlation of +1.00 means that as one trait increas- Calving season - The season(s) of the year when the es the other also increases—a perfect positive calves are born. Limiting calving seasons is the first step relationship. A correlation of -1.00 means that as one trait to performance testing the whole herd, accurate records, increases the other decreases—a perfect negative, or and consolidated management practices. inverse, relationship. A correlation of 0.00 means that as one trait increases, the other may increase or decrease— Carcass evaluation -Techniques of measuring compo- no consistent relationship. Correlation coefficients are nents of quality and quantity in carcasses. always between +1.00 and -1.00. Carcass merit - Desirability of a carcass relative to Crossbreeding - The mating of animals of different quantity of components (muscle, fat, and bone), USDA breeds (or species). Crossbreeding usually results in het- quality grade, plus potential eating qualities. erosis (hybrid vigor). Carcass quality grade - An estimate of palatability Culling - The process of eliminating less productive or based primarily on marbling and maturity and generally less desirable cattle from a herd. to a lesser extent on color, texture, and firmness of lean. Cutability - An estimate of the percentage of salable Carrier - A heterozygous individual having one reces- meat (muscle) from a carcass versus percentage of sive gene and one dominant gene for a given pair of waste fat. Percentage of retail yield of carcass weight can genes (alleles). For example, an animal with one gene for be estimated by a USDA prediction equation that polledness and one gene for horns will be polled but can includes hot carcass weight, rib eye area, fat thickness, produce horned offspring when mated to another animal and estimated percent of kidney, pelvic, and heart fat. carrying the gene for horns. Deviation - A difference between an individual record Central test - A location where animals are assembled and the average for that trait for that contemporary from several herds to evaluate differences in certain per- group. These differences sum to zero when the correct formance traits under uniform management conditions. average is used. A ratio deviation is the ratio less the average ratio or 100. 2 Beef Cattle Handbook Dominance - Dominant genes affect the phenotype F1 - Offspring resulting from the mating of a purebred when present in either homozygous or heterozygous (straight-bred) bull to purebred (straight-bred) females of condition. A dominant gene need only be obtained from another breed. one parent to achieve expression. Fat thickness - Depth of fat over the ribeye muscle at Double muscling - A simple recessive trait evidenced the 12th rib. It consists of a single measurement at a by an enlargement of the muscles with large grooves point three-fourths of the lateral length of the ribeye between the muscle systems especially noticeable in the muscle from the split chine bone. hind leg. Feed conversion (feed efficiency) - Units of feed con- Dressing percent - (Chilled carcass weight/live weight) sumed per unit of weight gained. Also, the production x 100. (meat, milk) per unit of feed consumed. Dwarfism - A recessive trait in which the skeleton is Fertilization - The union of the male and female quite small and the forehead has a slight bulge. gametes to form a new individual. This union combines two haploid cells to restore the diploid number of chro- Dystocia (calving difficulty) - Abnormal or difficult mosomes in the new individual. labor causing difficulty in delivering the fetus and/or pla- centa. Frame score - A score based on subjective evaluation of height or actual measurement of hip height. This score Economic value - The net return within a herd for mak- is related to processing weight at which cattle should ing a pound or percentage change of the trait in ques- grade choice or have comparable amounts of fat. tion. Freemartin - Female born twin to a bull calf (approxi- Effective progeny number (EPN) - An indication of mately 9 out of 10 will not be fertile). the amount of information available for estimation of expected progeny differences in cattle evaluation. It is a Generation interval - Average age of the parents when function of number of progeny but is adjusted for their the offspring destined to replace them are born. A gener- distribution among herds and contemporary groups and ation represents the average rate of turnover of a herd. for the number of contemporaries by other sires. EPN is less than the actual number because the distribution of Genes - The basic units of heredity that occur in pairs progeny is never ideal. and have their effect in pairs in the individual but which are transmitted singly (one or the other gene at random Embryo transfer - Removing fertilized ova (embryos) of each pair) from each parent to offspring.