Semen characteristics, sexual hormones and libido of Hy-Plus rabbit bucks influenced by a dietary multi-enzyme additive

Abstract

A total of 144 adult Hy-Plus rabbit bucks were randomly assigned into 4 treatments of 36 replicates each, in a completely randomised design. Animals were fed ad libitum on a basal diet supplemented with a multi-enzyme complex (EZ, including cellulases, xylanases, protease and a-amylase) at 0(EZ0), 1(EZ1), 3 (EZ3) and 5 (EZ5) kg/ton of feed. Total sperm count was higher (P<0.05) in EZ5 than in EZ0. Sperm motility increased with increasing levels of the EZ additive, being lowest for EZ0 and highest for EZ5 rabbits (P<0.05). Percentage of dead sperm was higher (P<0.05) in EZ0 than in EZ5 rabbits. Rabbit bucks that received the highest level of EZ in their diet had the shortest reaction time (22.31±3.17 s; P<0.05), whereas EZ5 bucks took 43.56±5.89 s to mount does for the first time after exposure. Blood testosterone, 17α-estradiol and progesterone levels were highest in EZ5 rabbits and lowest in EZ0 rabbits. Enzyme addition increased (P<0.05) sperm transit in estrus doe cervical mucus. Data suggested that the EZ additive in diets of adult Hy-Plus rabbit bucks was effective to improve both semen characteristics and sexual drive.