Effects of supplementing Erythrina brucei leaf as a substitute for cotton seed meal on growth performance and carcass characteristics of Sidama goats fed basal diet of natural grass hay

Abstract

The replacement value of dried Erythrina brucei leaf for cotton seed meal (CSM) on growth performance and carcass characteristics was evaluated. Twenty-five yearling buck goats (15.8 ± 1.4kg) were assigned into five treatments in a randomized complete block design: natural grass hay alone (T1) or supplemented with 100% CSM (T2), 67% CSM + 33% E. brucei (T3), 33% CSM + 67% E. brucei (T4), and 100% E. brucei (T5) on dry matter (DM) basis. Supplemented goats consumed more (P < 0.05) total DM and organic matter (OM) than the non-supplemented group, but the intakes were not influenced (P > 0.05) by the proportion of the supplements. The highest (P < 0.05) crude protein (CP) intake was observed in goats supplemented with CSM alone, whereas the lowest intake was observed in the non-supplemented group. Total CP intake decreased (P < 0.05) with increasing levels of E. brucei in the supplement mixture. The supplemented goats gained more (P < 0.05) weight than the control group. Apparent DM and OM digestibility was higher (P < 0.05) in supplemented goats than in the non-supplemented ones, but similar (P > 0.05) among the supplemented group. The digestibility of CP was higher (P < 0.05) for supplemented goats, except in those goats fed E. brucei alone, than the non-supplemented group. Slaughter weight, empty body weight, hot carcass weight, dressing percentage, rib eye muscle area, and total edible offals were higher (P < 0.05) for supplemented goats than for the non-supplemented ones. It could be concluded that E. brucei could be used as a substitute to CSM under smallholder production systems.