Effects of different dietary levels of two types of olive pulp and exogenous enzyme supplementation on the gastrointestinal tract size, immunology and hematology of broilers

Abstract

The effects of the dietary inclusion of olive pulp (OP) and the supplementation of a commercial enzyme blend (ENZ) on the gastrointestinal tract (GIT) size, and immune and hematological parameters were evaluated. In total, 600 one-day-old Ross 308 male broiler chicks were divided into 6 treatments according to a completely randomized design, in a 2×2×2 factorial scheme, consisting of the dietary inclusion of two olive pulp levels (50 and 100 g/kg in diet), two pulp categories (processed and unprocessed), and the inclusion or not of an enzyme blend. On d 42, birds were euthanized and blood samples were collected, and lymphoid, hematologic, and GIT organs were measured. The inclusion of 100g/kg OP in the diets increased jejunum relative weight (J%) and jejunum length (p ≤ 0.05). Processed OP reduced jejunum weight and length, J%, and left cecum length, serum triglycerides and VLDL cholesterol levels (p ≤ 0.05). Enzyme supplementation did affect any of the studied parameters (p> 0.05). The OP inclusion improved the GIT size, while processed OP reduced GIT measurements and serum lipid levels.