Nigerian J. Anim. Sci. 2018, 20 (4): 619-630 Nutritional Evaluation of Digitaria iburua (Black Acha) grains as feed resource in the diet of Broiler Chickens 1Ukim, C. I., 2Agwunobi, L.N., 2Kennedy Oko, O.O., 2Ayuk, A.A. and 2Robert, A. N. 1Department of Academic Staff Training & Development, Tertiary Education Trust Fund, Abuja 2Department of Animal Science, University of Calabar, Calabar Corresponding Author: [email protected] Target Audience: Poultry Farmers, Animal Scientists, Poultry Nutritionists, Cereal Researchers Abstract Feeding trial was carried out to investigate the nutritional value of black acha (Digitaria iburua) grains as feed resource using 240 day old Ross-360 broiler chicks. Four dietary treatments of sixty birds per treatment were randomly allotted to diets composed of unpolished whole black acha (UWBA), polished whole black acha (PWBA), unpolished milled black acha (UMBA) and polished milled black acha (PMBA) grains. At the end of eight weeks, feacal samples and tissues from some organs were collected and analyzed for nutrient digestibility and histopathology parameters respectively. Chemical analysis was also carried out for the different forms of black acha grains. Carcass characteristics were determined. Birds fed PMBA grains had best feed intake, weight gain, FCR. The economics of production showed no significant (P>0.05) difference across the treatments. Nutrient digestibility of birds fed PMBA diet showed significant (P<0.05) difference for all the digestibility parameters. The duodenum, gizzard and liver showed normal histological appearance. The dressed weight showed significant (P<0.05) difference with birds fed PMBA diet weighing more than the other treatments. It could be concluded that PMBA diet can be used in the diets of broiler chickens without adverse effect on performance and health status of the birds. Keywords: Digitaria iburua, black acha, broiler, performance, digestibility, histology, carcass characteristics. Description of Problem The high cost of maize has warranted The exorbitant cost of commonly questions on its continuous incorporation in available feedstuffs makes the final feed poultry diets. Moreover, competition for its use mixtures to be expensive and unaffordable by in human foods and industrial fuel production poor farmers. This has been a challenge to the limits its use for animal feeds. This has livestock industry in Nigeria (1, 2, and 3). necessitated research into non-conventional Grains account for more than 50 percent in energy supplying ingredients that would poultry diets, with maize being the most replace maize without compromising popularly utilized source of energy. The performance and profitability. One of such interest in search for alternative feed resources lesser known feed resources is acha. Research is of paramount importance, mainly because of indicates that feeding whole grains can the global demand for maize, which has improve starch digestibility (5) and is not exceeded production (4). detrimental to feed utilization by chicken when fed at low levels (5, 6). 619 Ukim et al In order to meet the food security goal of and methionine, which are important to the providing adequate and affordable food for the health of humans and growth of poultry which people at all times, recent research focus is are not readily found in most cereals. Black geared towards the exploitation of locally acha has high protein content (8.75%) and is available , nutritional viable, under-utilized found to be rich in leucine, valine and and easy to cultivate feedstuffs which have the methionine, and the grain has been regarded as highly needed dietary resources that can best nutritious and testing of all grains (13). replace or complement conventional feed There is not much literature on the energy ingredients in broiler feeds. value of black acha grains, though (14) Black Acha (Digitaria iburua) is a grain reported that black acha grains contain usually abundant in Nigeria, under-utilized and 19400KJ/kg. cheaper than maize. Digitaria iburua is a Although few studies on acha production member of the family graminae and the tribe have shown increasing importance of the crop Poaceae. It resembles the wild Digitaria amidst growing utilization as food, (15) longiflora (7) and grows under different soil highlights the need for more scientific types suitable for rice production (8). Acha is investigation on acha grains. Significant part of an annual cereal crop indigenous to West literature has focused on land productivity, Africa and is cultivated across the savannah. production forecast, adaptability, evaluation Black acha can be cultivated anywhere in and chemical composition, medicinal and Nigeria as it grows under varying conditions nutritional effects, the area of acha grain from poor dry upland soils to hydromorphic utilization as feed for livestock were not valleys suitable for rice production. It has a considered. It is on the basis of this, therefore, unique ability to tolerate poor and marginal that this research was undertaken to evaluate soils and can withstand drought (9). Large the feeding potentials and the impacts of either acha production for human consumption is polished whole, unpolished whole, polished however limited by the drudgery in post- milled and unpolished milled black acha grains harvest handling especially polishing of the in broiler chicken diets. This research effort small grains. This tends to become an will ultimately result to improve availability of advantage to exploit the production of the crop poultry feed, reduce cost of production, as a livestock feed. increase both efficiency and productivity of It is widely grown in Nigeria in Plateau, broiler chickens and above all increase protein parts of Bauchi, Kebbi, Taraba, Kaduna and intake among the populace. Niger States. Annually, farmers earmark about 300,000 ha to acha cultivation and yields of Materials and Methods 600-700 kg/ ha has been recorded which Experimental site translates to 180,000- 210,000 tonnes of grains The experiment was conducted at the annually (10). Acha is a grain with low toxicity Poultry Unit of the Teaching and Research as it contains low amount of anti nutrients Farm, University of Calabar, Calabar, Cross (tannins - 0.13mg/100g, phytate - River State, Nigeria. Calabar is located at 1.22mg/100g, trypsin inhibitor - latitude 4057‟N and longitude 8020‟E with an 38.45mg/100g, oxalate – 1.14 mg/100g and elevation of 38m above sea level (16). It has an cyanides - 0.07mg/100g) (11, 12). annual rainfall of 3000 - 35000mn and relative The major constituents of cereals are the humidity of 70 – 80 percent with average daily carbohydrates and proteins. Acha is the most temperature of 250C - 350C (17). nutritious cereals and a good source of cysteine 620 Ukim et al Collection of the test ingredient Data collection The polished and unpolished black acha Data were collected on feed intake and grains used for this study were bought from the weekly body weight changes while weight Jos Central Market in Jos Plateau State. The gain and feed to body gain ratio were unpolished black acha grains were manually estimated. At the end of the feeding trial (8 cleaned by hand picking of the chaffs. The weeks), a 7- day digestibility trial was polished and unpolished black acha grains conducted. Two birds per replicate of almost were then shared into two bags each and one the same weight across the treatment groups bag each of the polished and unpolished black were randomly selected and transferred to acha grains were milled and stored in a bag for metabolic cage, allowed to acclimatize to the used in the feed formulation. new environment for four days before their feacals were collected daily for 3 days. The Experimental diets feacal samples were oven dried at 800C, Four experimental broiler diets for starter weighed and kept in airtight container for and finisher phases (Tables 1 and 2) analysis. At the 56th day, twelve birds per respectively were formulated using Unpolished dietary treatment with mean weight equal or Whole Black Acha (UWBA), Polished Whole close to the treatment mean weight were Black Acha (PWBA), Unpolished Milled randomly selected and sacrificed by severing Black Acha (UMBA) and Polished Milled the carotid arteries followed by Black Acha (PMBA) as Treatments 1 - 4 exsanguinations after 12 hours feed respectively in line with (18) nutrient withdrawal. The carcasses were allowed to requirements of broiler chicks. bleed freely for 5 minutes, dry de-feathered and then re-weighed to obtain de-feathered Experimental birds, design and weight. They were then decapitated, management eviscerated and weighed to obtain the carcass A total of two hundred and forty (240) weights. The carcass was subsequently day-old Ross-380 broiler chicks purchased dissected into various primal cuts -breast, from Crown Hatcheries Entreprises, Issele- wing, thigh, drumstick and shank and Uku, Delta State were used for this expressed as percentage of live weight experiment. The birds were randomly weighed, according to (19) procedure. divided and allotted to four dietary treatments The histological studies on the liver, with sixty birds per treatment. Each treatment gizzard and duodenum were carried out at the was sub-divided into three replicates with Anatomy Diagnostic Laboratory of the twenty birds per replicate. University of Calabar Teaching Hospital The experimental birds/treatments were (UCTH), Calabar. The excised organs were arranged in a completely randomized placed in 10% of formalin and cut sections of design. Experimental diets and water were the different tissues were collected and placed provided ad-libitum for the birds in tissue cassette and dehydrated in ascending throughout the experiment that lasted for grades (70%, 90% and 100%) of alcohol for 56 days. The birds were raised in a deep 2hours each, four changes of absolute alcohol litter system with wood shavings as the for ihour to ensure proper dehydration and litter material. Vaccination and medication dealcoholized in three changes of xylene for programs were carried out accordingly and 15minutes each.