Comparative study on the feed intake, digestibility, and nitrogen balance of Kalahari Red goats fed with Tylosema esculentum (Burchell) A. Schreiber versus Medicago sativa L. as a protein supplement

Abstract

The study evaluated the dry matter intake, digestibility, and nitrogen balance in Kalahari Red goats fed grass hay ( ad libitum ), supplemented with Tylosema esculentum (marama bean) or Medicago sativa L. (Lucerne) containing diets. Sixteen weaner (8 males and 8 females) Kalahari Red goats (18 ± 5.6 kg initial live weights) were housed in individual metabolic cages and fed diets containing T. esculentum forage (i.e. leaves/vines) or M. sativa (as a control) in a randomised complete block design (RCBD). Each block (sex) and treatment combination was replicated four times. The animals had an adaptation period of 14 days which was followed by 7 days of total collection of faeces and urine. The data was analysed in SPSS version 29. From the results, dry matter intake did not differ significantly between treatments and sex. Goats fed the M. sativa diet had significantly higher ( p < 0.05) dry matter and organic matter digestibility (70.26% and 71.60%, respectively) compared to those fed the T. esculentum diet (65.88% and 66.41%, respectively). However, goats fed the T. esculentum diet had a higher ( p < 0.05) crude protein digestibility than those fed the M. sativa diet. The goats fed the T. esculentum diet had a higher ( p < 0.05) nitrogen balance (14.76 g/day) than those fed the M. sativa diet (7.52 g/day). The study concludes that T. esculentum forage can be effectively used as a protein supplement to replace M. sativa , which could increase the utilisation of underutilised legumes and productivity in ruminant livestock.