J. Pourreza, H. Classen,
Volume 6, Issue 3 (10-2002)
Abstract
Effect of supplemental phytase on phosphorus and protein utilization and performance of broiler chickens fed on eight different wheat varieties were evaluated. The phytate contents of wheat varieties were determined. In a completely randomized design with a 8*3 factorial arrangement, 384 day-old commercial male brioler chicks (HubbardPeterson) were divided into 96 groups, four chicks per group. Each of the 24 experimental diets (eight varieties) and three levels of phytase (zero, 500 and 1000 FTU/Kg) were given to four replicates for a period of 21 days. At 21 days of age, chickens of each replicate were weighed and killed by cervical dislocation. Ileal contents were collected and analyzed for P, N, phytate and chromic oxide. Left tibia of two birds in each replicate were removed, pooled and stored at -20oC for bone ash determination. There was a significant (P<0.03) difference in phytate contents between different wheat varieties. Effect of wheat varieties on body weight, feed conversion ratio and bone ash was significant (P<0.05). Added phytase improved body weight, feed consumption, feed conversion ratio and bone ash significantly (P<0.05). Phytase added at 500 FTU/Kg, improved protein digestibility significantly (P<0.01), but increasing the supplement to 1000 FTU/Kg had no further effect. Difference between enzyme levels (500 and 1000 FTU/Kg) was not significant regarding body weight, feed consumption, feed conversion ratio and bone ash. Overall addition of phytase to the diets containing wheat caused an improvement in performance, protein digestibility, and phytase phosphorus utilization in broiler chickens, and can, therefore, be used in diets to reduce feed cost and environmental problems.
A. Chakraei, J. Pourreza, A. Tabeidian,
Volume 12, Issue 43 (4-2008)
Abstract
This experiment was carried out to determine the nutritional value and the effect of different levels of tomato seed and pomace on performance of broilers. Corn grains and soyabean meals were replaced by tomato seed at levels of 6, 12 and 18 % and tomato pomace at levels of 3, 9 and 12 %. At first, the metabolizable energy of tomato seed and pomace was determined by the Sibbald method. In this experiment, 504 commercial broiler chicks (Ross 308) were used for 8 weeks (from 7 to 56 days old ) in a completely randomized design in 7 treatments with 4 replications per treatment. After 21 days, protein digestibility of the ration in illeum was determined. Apparent metabolizable energy was 3394 kcal/kg for seed and 2329 kcal/kg for pomace and crude protein was 31, 22.7, respectively . The result showed that body weight, protein digestibility of rations in illeum and carcass characteristics were not significantly different . Best energy and protein conversion efficiencies were obtained at the level of 6 % seed and 9 % pomace, that were not significantly different from control treatment. Cheeks fed with seed and 12% tomato pomace had significantly (p<0.5) higher feed intake than control group.The difference between diets containing 6% seed and 3% pomace and control group was not significant regarding feed conversion ratio.
