ABSTRACT

Thirty six (36) mongrel rabbit bucks averaging 4-5 months were used in a completely randomized design (CRD) to study the impact of Aspilia africana and selenium on their growth, physiological and reproductive parameters. Nine rabbit bucks were allocated to each of four treatment groups. Treatment one (T1) was the control, comprising only concentrate; T2, was concentrate supplemented with Aspilia africana, treatment three (T3) was made up of  concentrate supplemented with selenium, while (T4) was concentrate in a combination of Aspilia africana and selenium in a balanced ration. Growth performance showed that final weight, weight gain, daily weight gain and Feed Conversion Ration of the rabbit bucks were significantly (P<0.05) different among the treatments. Final weight of T1 (1631.72g) and T3 (1688.13g) were not significantly (P>0.05) different from each other but were lower than those fed Aspilia africana T2 (1831.69g) and much lower than T4 (1933.55g). Weight gain and daily weight gain results followed the same trend as in the final weight. Carcass characteristics results indicated that exception of forearm, all other parameters had significant (P<0.05) differences across the treatments. Live weight result showed that T2 (1743.33g) and T3 (1646.67g) were not significantly (P>0.05) different from each other but were significantly (P<0.05) higher than T1 (1533.33g) and significantly lower than rabbit bucks in T4 (1883.33g) which was the highest. In the same trend, dressed weight,thigh,drumstick,breastcut,pelt,shoulder and head weight results showed that rabbit bucks in T2 and T4(Aspilia group) were exceptional followed by T3(selenium group). Organ weight results showed that liver, right kidney, left kidney, spleen and lungs showed significant (P<0.05) differences across the parameters. However, the results showed that there was a major improvement in organs of those fed T2 (Aspilia africana), T3 (selenium) andT4 (Aspilia africana + selenium) respectively. Semen characteristics results showed that, gross motility, live sperm proportion, sperm concentration, total sperm per ejaculate and viable sperm were significantly (P<0.05) different across the treatment groups. Gross motility of bucks fed selenium-supplemented diet, T3 (72.67%) and T4 (72.67%) showed no (P>0.05) significant differences but were significantly (P<0.05) higher than those in T2 (63.00%) and slightly higher than T1 (69.00%).  Live sperm concentration, sperm concentration, total sperm per ejaculate, and viable sperm of the rabbit bucks followed the same trend. Seminal plasma results showed significant (P<0.05) differences in glucose, glutamic acid and sodium. Values obtained in glucose showed that T2 and T4 had no significant (P>0.05) differences among them but were higher than those in T1 and T3. Glutamic acid and sodium showed that those fed T2 and T3 were significantly higher than those in T1 and T4, respectively. With the exception of scrotal and testicular circumferences, testicular morphometry parameters, had no significant (P>.0.5) differences. Bucks in T3 and T4 (selenium supplemented) had higher mean value than those in T2 (only Aspilia) and T1 (control). Result obtained in serum biochemical indices showed that total protein, bilirubin, cholesterol, AST and albumin had significant (P<0.05) differences among the parameters. Values obtained showed that Total protein, AST and albumin showed no significant (P>0.05) differences among one another across the treatments (2, 3 and 4) but were significantly (P<0.05) higher than those in T1 (control). Identical mean values were observed in bilirubin in treatments (1, 2 and 3) but were significantly (P<0.05) lower than that in T4 (0.84 mg/dl). Cholesterol result showed that T3 and T4 were not significant from each other but higher than those of T1 and T2. It was observed in this study that micronutrient (Selenium) when supplemented with Aspilia africana in a right proportion(0.01-0.02mg/kg of feed) in a diet would help to improve reproductive performance of rabbit bucks as it arrests reactive oxygen species (ROS) or the free radicals because of its antioxidant nature.