Effects of feeding various levels of full fat soybean extruded at high temperature on performance, serum components and intestinal morphology of broiler chickens

Abstract

This study was conducted to evaluate the effect of dietary levels of extruded full fat soybean (EFFSB) on growth performance, physiological enzymes and intestinal morphology of broiler chickens at market age. A batch of FFSB was wet-extruded at 170°C for 15 s to provide the EFFSB. Ross 308 male broiler chicks (144 one-day old) were divided into 12 groups of 12 birds each and allocated to one of the starter, grower and finisher diets containing 0%, 7.5% and 15% of EFFSB. Feed intake and weight gain of chicks fed the diet containing 15% of EFFSB were significantly (P < 0.05) reduced compared with those fed the control diet during 0–10 days of age, but were not influenced during grower and finisher stages and the whole period (P > 0.05). The triglyceride and low-density lipoprotein (LDL) concentrations in blood serum were significantly (P < 0.05) decreased with an increase in dietary levels of EFFSB at 42 days of age. Length of villi and villus absorptive surface area in duodenum section were linearly decreased (P < 0.05) with an increase in dietary level of EFFSB (P < 0.05), although crypt depth and villus length : crypt depth ratio were not affected (P > 0.05). These morphological criteria were not affected by the dietary level of EFFSB measured in jejunum and ileum sections (P > 0.05). It is concluded that the use of EFFSB in feed may reduce the duodenal surface area and serum triglyceride and LDL cholesterol concentrations, but has no effect on performance of broiler chickens at market age.