In Vitro Digestibility and Fermentation Kinetics of Agricultural By-product used as feed for Sheep in Trinidad, West Indies

Abstract The objective of this study was to determine the in vitro digestibility and gas production of agro-industrial by-products fed to sheep. This was done to determine the effectiveness of agro by-products as alternative feedstuff for sheep to reduce the importation of foreign feed ingredients. Two alternative feeds were formulated using the following by products: cocoa hulls and shells (CHS), coconut seed meal (CSM), powdered bean (PB), Moruga Hill rice bran (RB), Moruga Hill rice hulls (RH), corn stover (CS) and seaweed. In vitro gas production was measured for all three feeds treatments for a total of 72h. The three feed treatments consisted of a formulated sheep and goat ration from a local feed mill (T1) and two pelleted feeds prepared using alternative feed ingredients that were mentioned above (T2 and T3). Chemical composition of the commercial feed (T1) had higher crude protein content (CP) than the alternative feeds. However, dry matter (DM), organic matter (OM), ash, NDF, ADF and ADL were higher in the alternative feeds. In vitro, ruminal fermentation kinetics results showed that gas production from the immediately soluble fraction (a) was significantly different (p < 0.05) for the T1 as compared to T2 and T3. Potential degradability (PD) also showed a significant difference (p < 0.05) between the feed treatments. Fermentation parameters showed that there was a significant difference for metabolizable energy (ME) for all tree feeds (p < 0.05), organic matter degradability and methane (CH4) production was significantly different (p < 0.05) for the commercial feed (T1) compared to the alternative feeds (T2, T3). The agricultural by product feeds had slower degradability in comparison to the conventional feeds. However, the alterative feeds had less gas and methane production in comparison to the conventional feeds. Thus, the agricultural by product feeds can be utilized as an alternative to feed sheep due to its low gas and methane production. Therefore, these by-product feeds can be a suitable alternative for sustainable sheep production in the tropics.