Hormonal Assay and Reproductive Performance of Rabbits Fed Pawpaw (Carica papaya) Leaves as Feed Supplement

Aims: To evaluate the effect of Carica papaya leaves on some reproductive hormones of male and female rabbits, and monitor their reproductive performance.

Study Design: The experimental design used for the study was Completely Randomized Design.

Place and Duration of Study: Department of Animal Science, Faculty of Agriculture, University of Calabar and Haematology/Pathology and Microbiology Laboratory, School of Health Technology, Calabar, Cross River State. Feeding trial lasted for ten weeks.

Methodology: Twenty-seven sexually matured crossbred (New Zealand White x Chinchilla) rabbits (eighteen does and nine bucks). Rabbits were randomly assigned to three dietary treatment groups made up of three replicates comprising of 1 buck: 2 does (mating ratio/replicate). Dietary treatments: control (T1) - fed concentrate and potato (Ipomea batatas) leaves; (T2) - fed concentrate and fresh pawpaw leaves; (T3) - fed concentrate and wilted pawpaw leaves. Blood samples were collected from six animals (3 does and 3 bucks) per treatment group, from the marginal ear vein. This was done a day before mating and two weeks post-mating (before feeding in the morning). Test for hormonal parameters in blood serum (testosterone, luteinizing hormone (LH), follicle stimulating hormone (FSH), Progesterone and Estradiol) were carried out with the aid of tube-based enzyme immunoassay (EIA) method.

Results: Reproductive parameters evaluated were observed not to be affected by dietary treatments. Follicle stimulating hormone levels increased between pre-mating and post-mating as a result of ovarian factors. Luteinizing hormone was relatively lower during pregnancy. Progesterone levels also increased within the period before mating to post mating for rabbits fed fresh pawpaw leaves (8.25 to 9.14 ngmL-1) and wilted pawpaw leaves (7.93 to 8.80 ngmL-1).

Conclusion: Pawpaw leaves can be served to rabbits either in its fresh or wilted state without affecting reproductive parameters assessed in this study. Results of hormonal assay did not reveal any adverse effects due to dietary treatment on the rabbits.