José Arce-Menocal

Most grains and vegetable feedstuffs used in commercial poultry feed contain phytates and polysaccharides—non-starchy chemical structures that are not degraded by digestive tract enzymes. Exogenous enzymes optimize the use of dietary ingredients. This study aimed to determine whether combining β-mannanases (400 g/ton) and phytases in broiler sorghum–soybean diets could improve performance and immunity in broilers. Four diets were randomized in a 2 × 2 factorial design, with two phytase levels (500 or 1500 FTU/kg) and β-mannanase supplementation (0–400 g/ton; 158 million units/kg minimum enzyme activity). Six replicate battery cages of 10 chicks were fed each diet ad libitum. To assess cellular and humoral immune responses, 10 birds per treatment were euthanized on day 21. Supplementation with β-mannanase enzymes led to increased body weight and a higher feed conversion index (FCI) (p < 0.05). The phytase factor improved the FCI at 1500 FTU/kg (p < 0.05). Supplementation with β-mannanases improved the immune response by increasing the IgA concentration in the duodenum (95%) and total serum immunoglobulins (p < 0.05). The morphometric index increased in all organs (p < 0.05), and the heterophile/lymphocyte ratio (HLR) decreased by 50% (p < 0.05). Supplementing broilers with β-mannanases in sorghum–soybean meal diets with phytases improved their performance and immunity.

This study was conducted to evaluate the productive performance, intestinal health, and description of the cecum microbiota in broilers supplemented with β-mannanases (MNs) and bacteriophages (BPs). Six hundred one-day-old broilers were divided into four groups and fed one of the following diets: CON—corn–soybean meal + 10 ppm enramycin (ENR); MN: CON + 500 ppm MN; BP: CON + 500 ppm BP; MN + BP: BP + 500 ppm MN. The BP and MN factors showed similar performances to ENR. MN improved the concentration of IgA in the jejunum at 35 days of age. The morphometric index (IM) of the thymus increased by adding MN, while BP increased the liver and thymus IM. The histological analysis showed that BP and MN improved the intestinal morphology. MN + BP showed a tendency to decrease the abundance of Proteobacteria and increase the abundance of Bacteroidetes, indicating better microbiota function. In conclusion, our results demonstrate that the combination of MN + BP has potential in poultry nutrition; however, we highly recommend further experiments to confirm this hypothesis.