ارزيابي عملكرد برخي مكمل هاي ويتاميني در تغذيه جوجه هاي گوشتي

Evaluation of Some Vitamin Supplements on Broilers Performance

An experiment was conducted in order to evaluate five synthesized vitamin premixes including: 1-NRC"s(1994) recommended requirments, 2- one half of NRC"s recommended requirments, 3- 1.5 times of NRC"s recommended requirments, 4- two- fold of NRCʹs recommended requirements, 5-poshtibani Co. recommended levels and three commercial vitamin premixes in feeding Arian broiler. This experiment was carried out using completely randomized design (CRD) with 480 sexually mixed broiler chickens including 3 replicates in 24 pens. Different vitamin premixes had no significant effects on feed consumption and weight gain in various experimental periods and total experimental period. The feed efficiency was significantly affected (P<0.05) with vitamin premixes in starter period. One-half NRCʹs recommended requirements had the lowest feeding efficiency as compared to other premixes(1 .79), but there were not significant differences between the other vitamin premixes. Various vitamin premixes had no significant effects on the carcass characteristics and mortality rate. The results of this experiment indicated that the NRCʹs recommended requirements have the best performance and the lowest feed cost per kilogram weight gain than other vitamin premixes.