Saccharomyces boulardii e Saccharomyces cerevisiae na alimentação de frangos de corte alojados em diferentes substratos de cama

Abstract

This study aimed to evaluate the performance, carcass yield, and intestinal morphometry of broilers supplemented with Saccharomyces boulardii and Saccharomyces cerevisiae as well as the characteristics of different litter substrates. 270 1-day-old broilers of the Cobb 500 strain were used in a completely randomized 3x3 factorial scheme, distributed in 45 experimental pens totaling 9 treatments and 5 replications each. Feed intake, weight gain, feed conversion, carcass characteristics and edible viscera and litter characteristics were evaluated during the period from 1 to 42 days of age of the chickens. The results demonstrated that there was no significant interaction between the type of litter substrates and yeast supplementation on feed intake, feed conversion and weight gain. However, weight gain was higher in chickens housed in rice husk bedding. Supplementation with yeast did not improve the performance of the chickens. S. boulardii impaired the feeding conversion of the animals in the period from 1 to 21 days of age. On the other hand, the multivariate analysis indicated lower carcass weights, edible cuts and viscera weights, for animals supplemented with S. boulardii and housed in a bed of mixture of shavings and rice husks and also for animals supplemented with S. cerevisiae and housed in wood shavings bedding. There was no effect of litter type and yeast supplementation on ileum morphometry, except for length of the villi which was higher in chickens raised on litter composed by mixing 50% of shavings and rice husks substrates. The wood shavings presented the physical properties that best meet the needs of broiler production. There was no large effect size of supplementation with S. boulardii and S. cerevisiae, compared to the control group on the bacteria count in the litter over the experimental period. The moisture content and pH of the litters were not affected by yeast supplementation or substrate type. Supplementation with yeasts and types of bedding substrates did not affect the frequency of pododermatitis lesions, except in the incidence of mild lesions that were higher in rice husks and 50% mixture of rice husk and wood-shavings.