Growth performance, intestinal morphometry, and blood serum parameters of broiler chickens fed diets containing increasing levels of wheat bran with or without exogenous multi-enzyme supplementation during the grower and finisher phases

Abstract

In developing countries, wheat bran (WB) is extensively used in poultry diets. However, it contains non-starch polysaccharides. The use of exogenous enzymes increases the digestibility of this feed ingredient. The objective of the study was to investigate the effects of multi-enzyme (XGP) on the growth performance, intestinal morphometry, and blood-serum parameters of broilers fed diets containing increasing levels of WB. A total of 720 Cobb 500 seven-day-old straight-run chicks (average BW = 156 ± 0.95 g) were randomly assigned to one of eight dietary treatments with six replicates each. A 2 × 4 factorial design, with two levels of XGP (0 or 360 g/ton) and four levels of WB (0, 4, 8, or 12%) was used. BW, ADG, ADFI, and FCR were determined at 14, 28, and 42 days. Birds were euthanized on day 42 for hematological and morphological measurements. There was a WB × XGP interaction for BW (P = 0.032) and ADG (P = 0.040) but not for ADFI or FCR at 42 d of age driven mainly by the inclusion level of WB. In addition, the main effects of WB or XGP inclusion did not influence ADFI of broilers. However, the overall FCR improved with XGP inclusion while increasing WB level linearly (P = 0.003) increased it. XGP × WB (P = 0.036) was observed for villi height (VH), villi height to crypt depth ratio (VH: CD), and high-density lipoprotein cholesterol (HDCL) but not for other blood parameters. These interactions were attributed to both the level of WB and XGP addition to the diets. Besides, the addition of XGP decreased blood serum cholesterol, red blood cells, white blood cells, hemoglobin, and hematocrit. Thus, the WB level did not have any adverse effect on feed intake but linearly increased the overall BW, ADG, and FCR of broilers. However, enzyme addition improved overall FCR and increased broiler VH, VH: CD, and HDCL while decreasing blood serum cholesterol. In conclusion, supplementing wheat bran diets with multi-enzyme improved FCR, increased blood serum HDCL, and decreased cholesterol.