Adição da parede celular de levedura (Saccharomyces cerevisiae) na dieta para frangos de corte

Abstract

This experiment aimed to determine the effects of yeast cell wall (Saccharomyces cerevisiae) (CWSc) inclusion in diet for broiler chickens raised in cages on the performance during 09- 21, 22-33, 34-39 and 09-39 days old, carcass characteristics, organ weight, digestibility of the diets, total counts and identification of coliforms in the ileum. The study design was randomized blocks, where blocks were floors of the cage, with three blocks, with five treatments and six replicates of 10 birds each, totaling 30 plots and 300 birds. Treatments used: reference diet with avilamicin; reference diet; reference diet with 0,1% cell wall of Saccharomyces cerevisiae (CWSc); reference diet with 0,2% of CWSc; reference diet with 0,3% of CWSc. In the period from 09 to 21 days of age the highest level of CWSc negatively influenced weight gain. In the period from 34 to 39 days, the level of 0,1% of CWSc provided better weight gain compared to treatment with antimicrobials, while the birds of the other treatments had intermediate values for this characteristic. Lower viability was observed in the period of 22 to 33 days of age to broilers fed diets with reference diet, while the other periods of age showed no differences between treatments. There were no statistical differences to feed consumption and feed conversion in period of 09 to 21 days of age, to feed consumption, weight gain and feed conversion in period of 22 to 33 days of age and to feed consumption and feed conversion in period of 34 to 39 days of age. In the total period of 09 to 39 days of age, were not significant differences between treatments for the performance variables. For carcass characteristics the highest value for weight was in the treatment with 0,1% of CWSc, the treatment with 0,3% had lower value. Absolute weight of drumstick and thigh+drumstick showed higher weight for the diets with 0,1% and 0,2% of CWSc, the lowest weight for the level of 0,3% and intermediate weight for the other treatments. The other parameters were not affected. There was no influence of CWSc and the antimicrobial on digestibility and total count of coliforms in the ileum. Changes were observed in the identification of the ileal microbiota as treatment change. The inclusion of CWSc can be performed up to 0,2% in the diets for broiler chickens without compromising animal production, metabolizability of nutrients and counts of coliforms in the ileum. The conclusion is that the CWSc may have diluted share, compared to performance enhancers in antimicrobial free diets.