Title : Effect of different cutting intervals on the nutritive value, in vitro dry matter degradability and intake relative palatability indices of Macrotyloma axillare legume residues and grass hay in Boer goats
Generally, forage legumes are well-known for enhancing feeding value, due to their high crude protein (CP), vitamins and minerals. In tropical southern Africa, climate change is worsening the challenge of feed shortage from natural pastures. The main aim of the current research was to determine the effect of different cutting intervals on the nutritive value, in vitro dry matter degradability, intake and relative palatability indices of Macrotyloma axillare legume residues and grass hay in Boer goats. The current study was conducted under the North West University experimental farm (Molelwane), North West Province, Mafikeng, South Africa. Macrotyloma axillare legume was planted as monoculture in December 2021 in a large area under irrigation. Legume was cut in different interval (30, 60 and 90) days. Blue buffalo (cenchrus cilliaris) grass was harvested at post flowering stage. For grass and all cuttings, legume samples were ground to pass through a 1-mm sieve, oven dried and placed in an airtight containers pending chemical analysis.A total of castrated ten (10) male Boer goats (weighing 20.4 ± 3kg) were used. Rumen fluid was collected from a fistulated Bonsmara cow to evaluate in vitro degradability, the cow was fed Macrotyloma axillare legume and cenchrus cilliaris grass hay. Feeds were used as treatments and goats as replicates in a completely randomized design. One-way analyse of variance was used to analyse the data attained from the experiment using the GLM of SAS (2010) in a completely randomized design. . Significant (P<0.05) variations were observed in intake and palatability among the grass and different cutting intervals throughout the experimental trail. Based on the findings, the 60 day cutting interval had highest crude protein, IVDMD, intake and palatability and lowest fibre contents. The results of this research proved that inclusion of Macrotyloma axillare legume in boer goats feed can meet their nutritional requirements. In conclusion, this suggest that Macrotyloma axillare cut at 60 days can be included in ruminants diets as protein supplement for ruminants fed low quality grasses. There is a need to assess the productivity of ruminants fed the Macrotyloma axillare legume forage harvested at 60 day.