Aditivo simbiótico em dietas de poedeiras na fase de produção

Abstract

With the banning of antibiotics as growth promoters in the poultry diet, alternatives such as probiotics, prebiotics and symbiotics are sought, in order to guarantee performance and maintain animal productivity. The objective of this research was to evaluate the performance and quality of eggs, hematological and biochemical responses of laying hens fed diets containing symbiotic. 252 laying hens of the Dekalb White, 46-week age, were used. The design was completely randomized, with 6 treatments, 6 repetitions and 7, consisting of: T1-Control diet based on corn and soybean meal, without additives (DC); T2- Control diet containing meat and bone meal (FCO); T3- Diet containing FCO supplemented with zinc bacitracin (BZ); T4- Diet containing FCO and addition of 0.1% of the symbiotic for birds that did not consume the additive in the brooding phase; T5- equal to T4, supplied to birds that did not consume the additive during the rearing phase and T6- equal to T4, supplied to birds that did not consume the additive during the rearing and rearing phases. The data were analyzed by PROC GLM from the Statistical Analysis System program version 9.4 and the means were compared using the orthogonal contrast method (P≤0.05). There was an effect of the symbiotic (P <0.05) feed intake and feed conversion compared to birds that received antibiotic-containing diets. There was also an effect (P <0.05) of the control diet with meat and bone meal on the average weight of eggs produced, which were higher and on egg quality an effect was observed for yolk weight, yolk percentage, weight of bark and the percentage of bark for birds fed with the treatment that contained antibiotics, compared to those that received diets containing symbiotic. As for the parameters of hematology and biochemistry, the effect of antibiotic was observed in the ALT variable, which obtained higher values in relation to treatments that received symbiotic. The reference diet provided higher concentrations of urea due to the treatment containing FCO. There was also an effect of the symbiotic for the variable total proteins, which had higher levels when compared to the treatment containing antibiotics. There was an effect of the symbiotic-containing diet for albumin and creatinine, which showed lower values. For hematology data, a symbiotic effect (P <0.05) was observed for the CHGM variable, where birds fed with the additive showed lower values compared to birds that received a diet containing BZ. There was also an effect for thrombocytes and relative eosinophils, that birds fed with symbiotic showed higher values compared to those that received the treatment containing BZ. Other parameters such as total plasma proteins, lymphocytes and heterophiles also showed a symbiotic effect. It cant be concluded that diets containing symbiotic improve responses of performance variables, egg quality and alter hematological and biochemical responses, compared to diets containing antibiotics.