EFFECT OF PROSTAGLAND IN Fza ON THE SEMEN PICTURE OF NAGTIVE BULLS

SUMMARY Two Native bulls 4-6 years old were incuded in the present stady. 15 ejacuates with a 10 minutes interval in between were collected in a period of three times from bull A as a control be fore injection of prostaglandin F2a. 17 ejaculates with a 10 minutes interval in between were collected in aperiod of three times from bull B as acntrol. Bull A injected with Gomg PGFza for two times. 17
ejaculates with a 10 minutes interval in between were collected in a period pf three times from bull B as a control. Bull A injected with 60 mg PGFza for two times, one hour ofter injection 8 ejaculated with a 10 minutes interval in between were collected in the first time and 7 ejacultes in the second time. Bull B injected with 30 mg PGF2a for two times, one hour after injection 5 ejaculates with a 10 minutes interval in between were collected in the first time and 9 ejaculates in the second time. Semen collected after PGF2a injection (60 mg) had a gighly significant (p < 0.01) increase in both the percentage of spermatozoa with forward motility and total abnormalities. Bull A showed an improvement in libido, the mean sprem cell concentration tended ti increase while the mean volume of ejaculate, PH and mass activity revealed no response. Injection of 30 mg PGFza in Native bulls resulted in a significant increase (P<0.05) in the mean volume of ejaculate and a highly significant (P<0.01) increase in the percentage of total abnormalities, the libido showed slight impovement and the percentage of spermatozoa with forward motility tended to increase while th PH, mass activity and sprem cell concentration exhibted no response to prostaglandin F2a injection