Nutritional quality of early- or late- maturing varieties of groundnuts: Effects on digestibility and growth performance of sheep fed groundnut haulms

This study determined the digestibility and growth performance of sheep fed early- or latematuring varieties of groundnut haulms. Early-maturing varieties (90 days) included Chinese, Yenyawoso and Sumnut 23 whereas late-maturing varieties (110−120 days) were Sumnut 22, Azivivi and Manipinta. Each variety was cultivated on four replicate plots of 2.4 × 4.0 m2, 3.6 × 4.0 m2, 4.8 × 4.0 m2 and 6.0 × 4.0 m2. At maturity, all the varieties were harvested. The pods were separated from the haulms (leaves and twigs) and equal portions of the haulms were combined into early- or late-maturing varieties. Each of the combined haulms were then dried to a DM of 92% and crushed to a theoretical length of 3–4 cm before being used to formulate two diets that were fed to West African Dwarf growing rams (14.75 ± 2.52 kg) in experiment I. In experiment II, two fistulated Nungua Black Head sheep were used to determine the in-situ digestibility of early- or late- maturing groundnut haulms. Even though the concentrations of ADF (P = 0.01) and ADL (P = 0.02) were greater in the early- compared to late- maturing haulms, differences in in situ digestibility (P ≥ 0.03), growth performance (P = 0.69) of sheep were not significant. This study suggests that duration to maturity has no effect on the nutrient quality of groundnut haulms and on the growth performance of sheep.