An objective method for evaluating Angus and Hereford sperm motility

Angus and Hereford sperm motility was evaluated by an objective spectrophotometric procedure and by a conventional subjective ranking system. Semen was collected by electroejaculation and divided so that one group contained 6 Angus samples and one group contained 12 Hereford samples. Objective procedures indicated that Angus sperm was twice motile as Hereford sperm in 2.9% sodium citrate. This objective procedure depends on the orientation of sperm in a flowing liquid and then spectrophotometrically measuring the sperm's ability to return to randomness when the flow is stopped. During preparation for freezing with liquid nitrogen, microscopic subjective ranking of sperm motility was carried out. Three conditions were studied subjectively: (I) arrival at the laboratory, (II) pre-freeze, and (III) thawed samples. No significant differences in subjective evaluation of sperm motility was found between conditions or breeds. Preliminary results indicate that this objective procedure can distinguish between the sperm motility in 2.9% sodium citrate from two breeds of cattle. Use of this objective procedure for studies relating to fertilization and artificial insemination is evident and there is no theoretical reason why the procedure can not be used with other species.