Proximate Analysis, in vitro Dry Matter Degradability and Palatability Index of Legume Residues and Maize Straws for Ruminants

Abstract

Background: Legume residues such as leaves from cowpea and lablab plants can be accumulated in large quantities after fruits harvesting. These legumes can be incorporated in ruminants’ diets due to their high feeding value. They are rich in crude protein, vitamins and minerals when compared to grasses that normally deteriorate during dry seasons. This paper is focusing on determining effect of legume residues and maize straws on in vitro dry matter degradability (IVDMD) and palatability indices in ruminants. Methods: For palatability experiment, each of five male boer goats was provided with four feeding troughs carrying four different feeds (maize straws and 3 legumes = Lablab purpureus - lablab and 2 Vigna unguiculata - cowpeas - Dr Saunders and Betswit). The legume residues and maize straws were also analyzed for chemical composition and IVDMD. All data was subjected to a one-way analysis of variance. Result: Dr Saunders (230.7 g/kg DM) had the highest (P less than 0.05) crude protein content when compared to all diets. Lablab (126.3 g/kg DM) had the lowest (P less than 0.05) acid detergent lignin. The highest (P less than 0.05) condensed tannins concentrations (50.1 g/kg DM) was recorded for Betswit. The highest (P less than 0.05) in vitro dry matter degradability was recorded for lablab at 24 up to 72 hrs. Lablab had a higher palatability index (P less than 0.05) when compared to other diets. Intake (r2 = 0.955) and palatability index (r2 = 0.971) were positively and significantly (P less than 0.05) predicted from total phenolics on goats. Though lablab had better values in most parameters measured, all legumes can be highly recommended to supplement low-quality roughages such as maize straws and grasses.