Aditivos na alimentação de frangos de corte: desempenho, características morfométricas e funcionais

• Autor(a) principal: Alva, Juan Carlos Ríos [UNESP]
• Data de Publicação: 2014
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://hdl.handle.net/11449/113986
• topic: Frango de corte - Nutrição; Ácidos orgânicos; Antibioticos; Enzimas; Probióticos; Suplementos dieteticos; Probiotics

Acidifiers and probiotics are considered alternative feed additives (FA) for growth promotant antibiotics, and these FA have been shown to improve broiler performance and affect gut morphometrics. Two experiments were conducted to evaluate the effects of the dietary addition of two probiotics (Paenibacillus sp. and Bacillus subtilis) and citric acid on broiler performance, intestinal, pancreatic and hepatic morphometrics and pancreatic enzyme activity. For both experiments, four hundred d-old male Ross 308 chicks were placed in 20 floor pens with reused litter and fed common corn-soybean basal diets (BD) that contained salinomycin. The five dietary treatments utilized in the first experiment resulted from using the BD without feed additives (WFA) as a negative control, adding a growth promotant antibiotic (lincomycin) as a positive control, and adding Paenibacillus sp. at 30, 45 and 60 ppm. The same positive and negative controls were used in the second experiment with three other dietary treatments resulting from the addition of citric acid, Paenibacillus sp. and Bacillus subtilis (GalliPro®) to the BD. In both experiments, BW, feed intake (FI) and FCR corrected for mortality were evaluated at the starter (1-21d), grower (22-35d) and finisher (36-42d) phases and the whole grow out. At 14, 28 and 42d intestinal samples of one chicken per pen were collected to evaluate villi height, density and width and goblet cells in the duodenum, jejunum and ileum. At 28 and 42d of age, pancreatic amylase, trypsin and chymotrypsin activities were evaluated. In the first experiment, data were analyzed in a CRD with regression analyses of Paenibacillus sp. levels and orthogonal contrasts with positive and negative controls. Data in the second experiment were analyzed in a CRD with orthogonal contrasts against the positive control. In the first experiment, no significant effects (P>0.05) of Paenibacillus sp. inclusion levels were observed on ...