Chemical Composition and In Vitro Digestibility of Pomegranate Byproducts in Ruminant diet

Abstract

Digestibility of feeds can be measured using in vivo (direct method) and in vitro methods. The aim of this study was to measured chemical composition and in vitro digestibility of dried pomegranate seed pulp and pomegranate by-products silage by gas production technique. This research was conducted in the Department of Animal Sciences, Shiraz University. The experimental diets include dried pomegranate seed pulp (DPS), pomegranate seed pulp silage (fresh pomegranate seed pulp with 2% urea; FPS), pomegranate pulp silage (mixture of same amount of peel and seed pulp with 2% urea and 3% wheat straw; PPS+U), and the same silage mixture without urea (PPS). The chemical composition (protein, fat, neutral detergent fiber (NDF), and acid detergent fiber (ADF)) and volume of gas production were measured. The results showed the highest percentage of protein (23.33) and fat (16.75) were found in PPS+U and FPS, respectively. The dried pomegranate seed pulp had the maximum amount of NDF and ADF. The maximum gas production volume during 24 hours was found in dried pomegranate seed pulp. The constant gas production rate per hour (c) was not significantly different between the treatments, but other fermentation parameters were higher in DPS than other samples. In general, our results showed that DSP, despite higher amount of NDF, has higher gas production and more energy, and also the PPS+U, is an appropriated protein feed, that these two pomegranate by-products can be tested in in vivo studies by replacement for some part of the forage and concentrate in ruminant rations.