EFFECTS OF DIFFERENT VARIETIES OF GROUNDNUT (Arachis hypogaea L) HAULMS ON DIGESTIBILITY AND GROWTH PERFORMANCE OF DJALLONKÉ SHEEP

Abstract

Seasonal factors affect the availability and nutritive value of groundnut haulms. Hence some farmers prefer early-maturing varieties while others prefer late-maturing varieties. This study determined the effects of bale temperature on spontaneous heating of groundnut haulm bales, digestibility and growth performance of sheep fed early- or late- maturing 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. Split plot design was employed to cultivate each variety on 4 different 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. In experiment I, the groundnut haulms were baled and shade dried. During the shade drying, core bale temperatures and room temperatures were recorded at the same hour (3:03:00 PM) Greenwich Mean Time (GMT) in the consecutive days as it was done for the first day. Each of the combined haulms were then dried to a DM of 92% and chopped 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) every morning (07:00 am GMT) and every evening (05:00pm GMT). in experiment II. In experiment III, two fistulated Nungua Black Head sheep were used to determine the in situ digestibility of early- or late- maturing groundnut haulms. The concentrations of ADF and ADL were greater (P < 0.05) in the early- compared to late- maturing haulms whereas the extent of digestibility of the late-maturing varieties was higher than the early maturing variety. The intake and growth performance of sheep did not however differ (P = 0.69). This study suggests that duration to maturity has no effect on the nutrient quality of groundnut haulms and on the growth performance of sheep.