Dietary substitution of maize with processed cocoyam (Xanthosoma sagittifolium) as energy source for finisher broilers production
Authors: Onunkwo D. N. , Anyaegbu B. C. , Adedokun O. O. , Bassey E. G. 
Published: February 2021

Energy feed source like maize is expensive contributing about 50-55% of the cost of poultry and pig diets. Thus, the study was carried out to determine the dietary substitution of maize with soaked cocoyam Xanthosoma sagittifolum as energy source for finisher broiler production. The soaked cocoyam tuber meal was used to replace yellow maize in the diets of finisher broilers. Xanthosoma cocoyam corms were harvested, cleaned of soil and chopped into bits of about 0.2 cm. The chopped tannia was soaked in water in a large vat for 24 hours to reduce the ant nutrients and later on separated from the water and dried with microwave oven. The dried cocoyam was milled and then used. The proximate chemical composition showed that soaked cocoyam tuber meal contained 8.05% moisture, 91.95% dry matter, 10.08% ash, 2.01% crude protein, 1.60% ether extract, 3.80% crude fibre, 74.46% NFE and 3158.92Kcal/kg DM metabolizable energy. In the finisher broiler trial, the control diet contained maize as the main energy source while diets 2, 3, 4 and 5 contained 15%, 20%, 25%, and 30% soaked cocoyam tuber meal finisher diet was fed to a group of 30 broiler chicks for 4 weeks using completely randomized design. Each treatment was further grouped into 3 replicated of 10 birds each. The broilers were kept in deep litter and given feed and water ad libitum. Parameters measured included: initial body weight, find body weight, body weight gain, feed intake, feed conversion ratio, cost of production and carcass characteristic. In the finisher feeding trial, the finisher broilers on the control diet, diet 5 (30% SCYM), and diet 3 (20% SCYM) recorded similar feed intake which were significantly different (P<0.05) from those on the other diets. In terms of body weight gain, the finisher broilers on 20% soaked cocoyam tuber meal diet recorded significantly (P<0.05) high body weight than those on other diets while the finisher broilers on 25% soaked cocoyam tuber meal recorded the poorest body weight gain. It appeared that, the finisher broilers could not tolerate high levels of soaked cocoyam tuber meal in their diets. Cost of production (cost of feed x feed conversion ratio) was lowest for diet 5 (30% SCYM) N375 versus N422.99 for control diet in the finisher trial. The internal organs expressed as percent of the live weight were not affected by the treatments. The finisher broilers on diet 3 recorded the highest dressing out percentage of 73.90.There were no significant difference (p<0.05) on percentage wings and back cut of the finisher broiler group in all the diets. The finisher broilers on diet 4 (25% SCYM) yielded the highest percent breast muscle of 32.4% followed by those on 15% SCYM (diet 2) and 20 SCYM (diet 3). The finisher broilers on the control diet yielded the highest percent thigh of 18.3% and the poorest were those on diet 2(15% SCYM). The results of the trial have shown that soaked cocoyam tuber meal can be used to substitute maize at 20% in the diets of finisher broilers without affecting the weight gain, feed intake and feed conversion ratios as indicated in this study.