Effects of two probiotics (Paenibacillus ssp e Bacillus ssp), and lincomycin on broilers performance, intestinal, liver and pancreatic morphometrics, and pancreas enzymatic activity

Probiotics are considered alternative additives to antibiotic growth promoters, but the action and effectiveness are variable and require further studies. Thereby, this study was conducted to analyze the effects of the addition of two probiotics (Paenibacillus ssp e Bacillus ssp) at the broilers performance, intestinal, liver and pancreas morphometric, and also, its pancreatic activity. A total of 400 d-old male Ross 304 chicks were placed in 20 floor pens with reused litter, and fed diet based on corn and soybean meal as basal diets (BD) that contained salinomycin. It consisted of treatments: BD without feed additives as a negative control, and BD with growth promotant antibiotic (lincomycin) and the Paenibacillus ssp e Bacillus ssp as a positive control. At the performance, the weight gain (WG), feed intake (FI) and feed convertion (FC) were evaluated at starter (0-21d), grower (22-35d) and finisher (36-42d) phases, and also throughout the whole grow out phase. At 14, 28 and 42d, one chicken per floor pens was collected to evaluate villi length, density and width, and the goblet cells in the duodenum, jejunum and ileum, as well as the density of the liver Kupffer cells, cells and serous pancreatic acini. At 28 and 42d-old pancreatic amylase, trypsin and chymotrypsin activities were evaluated. The data were analyzed in a completely randomized design (CRD) with orthogonal contrasts against positive control. For all treatments, no significant effects (P>0,05) on BWG, FI, FC were observed in all evaluated phases, except on the FC in the finisher phase which was better (P<0,05) in the positive control. The villous morphometric was affected (P <0.05) by treatments in the initial phase. Broilers fed diet with Paenibacillus showed greater width of villi that the positive control. The length of the villi was less in those treated with Paenibacillus . It was concluded that the additives do not affect the performance of broilers, however, affect the intestinal morphometric.