EFFECTS OF CHRONIC STRESS ON MATING BEHAVIOUR AND SEMEN QUALITY OF NIGERIAN INDIGENOUS COCKS

Résumé

The present study was conducted to evaluate the effects of chronic stress (exogenous corticosterone, CORT) administration on the mating behaviour and semen quality characteristics in Nigerian indigenous cocks. A total of 36 matured birds consisting 9 cocks and 27 hens were used. Birds were randomly divided into two experimental treatments. Treatment 1 (control) cocks were given 0mg of CORT (4 replicate), while Treatment 2 (stressed) were given 2mg CORT/day orally for 5 consecutive days. After each administration the mating behaviors (number of successful mating, number of approach to hen, attempted mount and waltzing) cocks observed daily between 5:30-6:30pm. At the end of the 5th day, cocks were gently restrained and semen samples were collected via rectal massage for analysis. Data collected on semen parameters were subjected to Independent sample T-test, while data collected on mating behaviour was subjected to Mann-Whitney U-test all of SPSS Statistical package (version 21). Birds administered 2mg CORT/day showed a significant decrease in number of successful mating but no effect on other matting behaviours. Also, birds administered 2mg CORT/day showed no effect on semen quality. In conclusion, the administration of exogenous CORT (2mg/day for 5 days) to Nigerian indigenous cocks had a negative effect on successful mating but no significant effect on semen quality.