Morphometry of the Gastro-intestinal Tract in Broiler Finisher Fed Rice Offal Supplemented with Xylanase Enzyme

Abstract

The study was carried out to evaluate the effects of rice offal diets supplemented with xylanase on broiler birds. One hundred and twenty broiler chickens at four weeks of age were randomly allotted to four dietary treatments composed of graded levels of rice offal at 0% (control), 5%, 10% and 15% supplemented with equal levels of xylanase (10g/100kg of feed). Each treatment was replicated three times with 10 birds per replicate. No significant difference (P > 0.05) was observed on the performance of the birds. On the organ weights the crop had better development (P < 0.05) on rice offal diets (35.96, 37.27, and 48.90) as compared to control (35.20). But there was no significant difference (P > 0.05) and no particular trend on the results of all other organs weight. The morphometric analysis showed a significant difference (P<0.05) only in length of the liver with birds on control diet (11.43) having higher mean values. The proventriculus, small intestine and spleen though not significantly different (P>0.05) on both width and length dimensions, however showed a linear increase as the levels of rice offal in the diets increased. Feed cost per kg was reduced on enzyme supplemented diets as the level of rice offal increased. The feed conversion ratio on dietary treatments compared favourably with the control. There was decreased viscosity, increased intestinal transit/rate, reduction of water content in faeces that resulted in a good litter quality on the birds across the treatments. Rice offal supplemented with xylanase can therefore be included up to 15% in the diets of broiler birds without any adverse effect on the performance and gastro-intestinal tract.

Keywords: Exogenous enzymes, Fiber utilization, Growth performance, Poultry diets, Gastro- intestinal morphometry