The effects of short-interval ejaculation on semen quality and some biochemical parameters in dogs

Abstract

In the present study, ten ejaculates were obtained from each of seven German shepherd dogs. Only the sperm-rich fractions of ejaculates from each dog once a week with a mean interval of 60 min, were used during five weeks. Semen quality was examined in total of 70 semen samples. After this examination, semen samples were centrifuged (5000 g x 10 minutes) and seminal plasma were separated. Plasma total protein, calcium, phosphorus, magnesium, sodium and potassium and alkaline phosphatase were determined. The semen quality and biochemical findings were compared between the first and the second ejaculate following very-short interval ejaculation. There were no significant differences in the percentage of motility, live spermatozoa, acrosomal, tail and total morphological defects of the second ejaculate compared with that of the first ejaculate. However, there were significant lower values for the volume and the spermatozoal concentration in the second ejaculate than that of the first ejaculate (p < 0.05). There were significantly lower values for the total protein, calcium, magnesium and alkaline phoshatase of the second ejaculate compared with that of the first ejaculate. Positive correlations were found between spermatozoal concentration and AP; motility and sodium concentration. The semen quality in the first and the second ejaculate in all dogs was normal for fertility. In conclusion, when the first ejaculate is inadequate, collection of second ejaculate may be useful for cryopreservation or insemination with fresh semen in dogs.