XYLANASE AND PROBIOTIC IN BROILER DIETS
Additive. Enzyme. Microbiota. Viscosity.
Broiler diets are generally composed of ingredients of plant origin, which may have a high amount of non-starch polysaccharides, which are considered antinutritional factors in broiler nutrition. Thus, the use of enzymes and probiotics can ensure greater availability of nutrients of plant origin minimizing the effects of PNA's. Two experiments were carried out to study xylanase and probiotic supplementation in broiler diets. Experiment I was conducted at IFAM / Parintins, in an experimental house, conducted in a completely randomized design with four treatments, with six replications of seven birds each, in which the treatments consisted of: 01 - control diet; 02 - diet 01 + addition of probiotic; 03 - diet formulated with xylanase addition; 04 - Diet 03 + addition of probiotic. Performance, carcass characteristics and intestinal viscosity were evaluated. Experiment II was carried out in metallic cages at UFAM / Manaus, conducted in a delineated manner and with similar treatments to that described above, and all diets were supplemented with wheat bran and birds challenged with Eimeria. Performance, carcass, viscosity and intestinal pH and ileal microbiota were evaluated. In experiment I, the treatments influenced weight gain and feed intake, in which the isolated or combined supplementation of the additives did not differ, but led to greater gains over the diet without supplementation from 1 to 35 days of age. Intestinal viscosity was significantly lower in treatment with xylanase alone (1.01 cP). In experiment II, from 10 to 35 days of age, isolated xylanase and probiotic bedding provided greater weight gain. The reference treatment presented higher viscosity in duodenum (1.42 cP) and ileum (1.21 cP), and higher duodenal pH value (6.54), with a probiotic diet resulting in lower cecum pH value (6.11). The use of additives, alone or in combination, modulated the ileal microbiota, reducing the frequency of Clostridium microorganisms. Supplementation of xylanase and probiotic additives provides improvements in animal performance, intestinal viscosity and ileal microbiome. The positive results of the isolated xylanase and probiotic supply were similar to those obtained with the joint supply of these two additives, and no possible additive effect was proven.