Emenalom et al., 2004. Livest. Res. Rural Dev., 16: 33
Velvet bean (Mucuna pruriens) is a tropical legume, which has potential as an energy and protein supplement in livestock feeds. Unfortunately, the use of raw velvet bean in non-ruminant feeding is limited because of its content of anti-nutritional factors.
A 42-day feeding trial was conducted to determine the response of growing pigs to diets containing unprocessed, or processed (cracked, soaked and cooked) velvet beans. Unprocessed velvet bean seeds were dried and milled and incorporated at 15% dietary level, while another batch was cracked, soaked in water for 48 hours and cooked for 60 minutes, dried, ground and incorporated at 20%, 30% and 40% dietary levels. The control (0%) diet contained no velvet bean. Each diet was fed to four growing pigs. At the end of the 42nd day, two pigs per treatment were fattened for 7 days, fasted for 18 hours, slaughtered and eviscerated for organ weight determination. Unprocessed velvet bean at 15% dietary level significantly depressed the general performance of the pigs when compared with other groups. The groups on cracked, soaked and cooked velvet bean diets performed significantly better in growth rate and feed conversion than the group on unprocessed velvet bean and compared favourably with the group on the control diet. Unprocesed velvet bean significantly decreased the organ weights of the pigs. Mortalities recorded among the group on velvet bean were attributed to the treatments.
It is suggested that 15% dietary level of unprocessed velvet bean is toxic to pigs and that cracking prior to soaking in water and cooking allows for a successful use of the bean, up to 40% in the diets of growing pigs.