Substituição do antibiótico bacitracina de zinco pelo simbiótico para galinhas em pós-pico de postura

Abstract

This study aimed to evaluate the effect of the use of the symbiotic supplement composed of Saccharomyces cerevisiae, Bifidobacterium bifidum, Bacillus subtilis, Enterococcus faecium, Lactobacillus acidophilus, Glucans and Mannans in substitution of the antibiotic zinc bacitracin in the feeding of hens in post-peak laying period. (creates, recreates and posture). A total of 198 Dekalb White pullets, from 70 to 90 weeks of age, distributed in DIC with 6 treatments, 6 repetitions, being 3 repetitions with 5 birds and 3 repetitions with 6 birds, composing 33 birds per treatment were used. The treatments were composed of two base diets, the first one composed of corn and soybean meal (RR); another diet based on corn, soybean meal and meat and bone meal (FCO); and four more test diets formulated with FCO, being a diet with the addition of 0.05% of the zinc bacitracin additive (FCO+Bac Zn) provided from the initial, rearing and laying phases, respectively. The variables evaluated were: bird performance (feed intake, egg production, egg weight, egg mass and feed conversion), egg quality (evoscopy, egg weight, yolk color, albumen height, albumen weight , yolk weight, shell weight, shell thickness and percentages of yolk, albumen, shell and Haugh Unit) and values of apparent metabolizable energy (EMA) and Apparent Metabolizable Energy corrected by nitrogen balance (EMAn) apparent metabolizability coefficients of dry matter (CMAMS), crude energy (CMAEB) and crude protein (CMAPB). The data were analyzed, and the means were compared by Orthogonal Contrast (P<0.05). The contrasts were C1: RR vs FCO; C2: FCO vs BacZn; C3: BacZn vs Simb-C; C4: BacZn vs Simb-R and C5: BacZn vs Simb-P. For performance variables there was no significant effect (P>0.05). For egg quality, the variables candling and yolk color, there was a significant effect (P<0.05), where for candling the RR treatment had better eggshell than the FCO, for the RR and BacZn treatments they obtained better coloration of the eggshell. yolk, yolk weight had an effect for BacZn in relation to Simb-C and albumen percentage was better in RR. The yolk color variable by minolta showed an effect (P<0.05) of red and yellow color for RR and BacZn and for luminosity in Simb-R. For the digestibility, the CMAEB variable showed a significant difference for the RR and Simb-R. For the CMAPB variable, there was a difference in the FCO diet. In the CMAMS variable, there was a significant difference for the FCO, Simb-C and Simb-R diets. For the other parameters there was no significant effect (P>0.05). In this way, it is possible to replace the antibiotic with the symbiotic, for laying hens in post-peak laying, fed from birth, promoting similar results in performance and egg quality, obtaining better results in breeding and rearing for nutrient digestibility.