Three-year monthly variations in the spermiogram of Djallonke-breed rams in the Cote d’Ivoire forest region

Abstract

Monthly variations in the volume, mass motility and semen concentration were studied over three years in forty Djallonke rams in the forest area of Cote d’Ivoire. Two ejaculates were harvested weekly using an artificial vagina. For each year, the volume was lower before May (from 0.55 ± 0.03 to 0.75 ± 0.04 ml) than after (from 0.61 ± 0.8 to 0.9 ± 0.61 ml), when changes were significant except in 1993. The mass motility showed only significant decreases in the year (from 4.42 ± 0.06 to 3.5 ± 0.2), but with an increase between April and July (between 3.85 ± 0.01 and 4.45 ± 0.03). The concentration increased from April to August and significantly in June and July [from 3.36 ± 0.12 × 10^9 to 3.8 ± 0.12 × 10^9 spermatozoa (spz)/ml]. Overall averages for the three years showed i) an increase in volume from June (from 0.71 ± 0.02 to 0.77 ± 0.02 ml), and ii) a significant decrease in mass motility from February to April (from 4.28 ± 0.06 to 4.01 ± 0.1), in July (3.9 ± 0.1), in September (4.1 ± 0.07) and in December (3.92 ± 0.1). The concentration increased in June (from 2.95 ± 0.05 × 10^9 to 3.52 ± 0.07 × 10^9 spz/ml) and in July (3.18 ± 0.06 × 10^9 spz/ml). The variation of these parameters in Djallonke was thus annually different, non-characteristic and with no annual cycle. However, the period between April and August was more favorable to the increase of the parameters. Despite significant decreases in mass motility, the parameters were of good quality for artificial insemination throughout the year.