Effect of vitamin A, E, pyridoxine (B6), folic acid and biotin levels on the performance of broilers (1-42 days)

This experimental work was conducted to verify the effect of supplementation of vitamin A, E, pyridoxine (B6), folic acid and biotin in the diet of broiler, from 1 to 42 days of age. A total of 1144 Arbor Acres sexed day-old chicks was used in a completely randomized experimental. Five vitamins were tested individually in treatment 1 to 10. Treatments 11 and 13 contained all vitamins at high and low levels, respectively. All the treatments were compared to the average level of all vitamins (T12). Diets differed only in respect to the vitamin levels studied. The high and low levels of five vitamins studied were calculated to be 33.33% above or bellow the average level used by five corporated companies in Rio Grande do Sul and Santa Catarina. The level of the vitamins tested in the growing period was 83.33% of that used in the initial phase. The parameters evaluated were feed consumption, body weight, feed/gain ratio and feed efficiency. Final results at 42 days showed that weight gain was impaired significantly when low levels of vitamin E and B6 were used. Feed/gain ratio was also affected negatively by the use of low levels of vitamins A, E and B6. Feed efficiency for high levels of all vitamins was better than for the medium and low levels. It can be concluded that low levels of all vitamins fed in this study were not capable to maintaining high performance of broilers.