A Comparative Study on Digestive Parameters in an Indigenous Fat-tailed and a Conventional Dorper Sheep Fed on Maize Stover Crop Residue

The intake, dry matter (DM) digestibility, total mean retention time (TMRT) and weight changes were investigated in four fat tailed and four Dorper sheep fed on a maize stover crop residue. Animals were subjected to five dietary treatments, which were: 90, 135 and $180g\;DM/kgBW^{0.75}/day$ of chopped maize stover offered with urea, and in subsequent dietary treatments $180g\;DM/kgBW^{0.75}/day$ of stover supplemented with either dried bean husks or poultry manure. Although not statistically different (p>0.05) fat tailed sheep had higher maize stover intake than the Dorper sheep when expressed per metabolic body weight. The DM intake and digestibility increased significantly (p<0.001) in both sheep breeds when the maize stover offer levels were increased from 90 to $135g/kgBW^{0.75}/day$. Dorper sheep had significantly (p<0.001) higher DM digestibility and longer total mean retention times for both the liquid and solid matter than the fat-tailed sheep. Fat-tailed sheep gained 4.75 kg while Dorper sheep gained 3.75 kg over the entire experimental period. The weight change per dietary treatment was affected by the amount of maize stover and the type and amount of supplement consumed. The higher DM digestibility and longer total mean retention time in Dorper sheep shows that the breed has adapted to utilize the low quality roughage diets. An indigenous fat tailed, has the potential to ingest high volumes of fibrous feed and has higher voluntary intakes relative to its body size. The two sheep breeds are a valuable genetic resource in sub Saharan Africa that is characterized by long dry season with no readily available and affordable conventional feeds for small ruminants.