Effects of Replacement of Elephant Grass (Pennisetum purpureum) with Velvet Bean Hay (Mucuna pruriens) in Diets on Feed Intake, Digestibility and Nitrogen Metabolism of Growing Goats

Abstract

      A feeding experiment aimed at investigating the effect of replacement of elephant grass (Pennisetum purpureum) with velvet bean hay (Mucuna pruriens) at increasing levels in the diets on feed intake, apperent digestibility, nitrogen balance and purine derivatives was conducted. A total of 8 male crossbred (Jumnapari x Saanen) goats were randomly located in a 4x4 double Latin Square design and were housed in individual metabolic cages. The goats were given ad libitum one of four experimental diets. The basal diet composed of 200g corn powder and elephant grass, elephant grass was replaced with different levels (0%, 25%, 35% and 45%) of velvet bean hay harvested at 3-4 months of age. The intake and apparent digestibility of dry matter, organic matter and NDF increased significantly in animals fed diets replaced with velvet bean hay (P > 0,05). However, these figures were similar in animals given 35 and 45% velvet bean hay (P > 0,05). Increased levels of legume resulted in increased intake of nitrogen and nitrogen balance. The total excretion of urinary purine derivatives increased with increasing level of replacement (P > 0,05) and varied from 3.06 to 7.59 mmol/day. There was no significant difference in urinary purine derivatives between groups fed 35% and 45% velvet bean hay in diet (P > 0,05). It is suggested that elephant grass can be replaced by 35% velvet bean hay to improve nutritional values of a high fibre diet for growing goats.