Semen Characteristics of Yankasa Rams Following Cypermethrin Treatment

Abstract

This work was aimed to assess the semen characteristics of Yankasa rams following Cypermethrin treatment.Cypermethrin was used topically at the dose rate of 3mg/kg b.w (0.1ml/kg). Sixteen healthy Yankasa rams and weighing between 21.5kg and 43kg and between the ages of 18 and 30 months were used. The animals were divided into groups A and B. Group A was given 3% Cypermethrin as pour-on fortnightly for a period of twelve weeks. Group B was given distilled water at the same rate (0.1ml/kg), route of administration and period. Semen samples were collected weekly by the use of a battery powered hand held electro ejaculator. Results showed that Cypermethrin significantly reduced mean sperm concentration, motility, viability, semen volume and pH of Yankasa rams. The difference between the mean sperm motility of groups A and B in weeks 6, 7 and 8 were statistically significant (P<0.05). The values were 37.78 ± 5.21% and 82.11 ± 9.12%, 22.86 ± 4.10% and 73.42 ± 8.07%, 32.14 ± 10.17 and 67.86 ± 9.31% for groups A and B respectively. Semen volume was significantly higher in control rams at week 2 (P<0.05). The values were 0.36 ± 0.04ml and 0.93 ± 0.26 mlfor groups A and B respectively. The difference between the mean sperm concentration of groups A and B were statistically significant in weeks 5 and 7 (P<0.05). The mean sperm concentrations of groups A and B were3190 ± 499.76 x 10 6 /ml and 4558 ± 558.10 x 10 6 /ml, 1931 ± 102.57 x 10 6 /ml and 3300 ± 309.15 x 10 6 /ml for weeks 5 and 7 respectively. The difference between the mean percentage live of groups A and B were statistically significant in weeks 6, 7 and 8 (P<0.05). The values were 45.55 ± 4.75% and 82.22 ± 7.78% in week 6, 48.57 ± 5.95% and 84.29 ± 3.69% in week 7, 47.14 ± 9.44 and 74.29 ± 3.69% in week 8 for groups A and B respectively. By week 12 of the experiment, the mean semen pH values 6.60 ± 0.10 and 8.00 ± 0.09 for groups A and B respectively were significantly different (P<0.05).It was concluded that Cypermethrin lowers semen quality of Yankasa rams. It was therefore, recommended that Cypermethrin be used with caution inrams and further studies on the meat residue be done for public health concern.