Sperm morphology in relation to semen cation concentration in Yankasa rams

Abstract

The morphological appearance of sperm cells is a major criterion in semen evaluation. The optimal production of semen of high biological value is influenced by numerous factors. Therefore, a study was conducted to  evaluate the relationship between sperm morphological characteristics and semen cation concentrations in 62  rams of Yankasa breed of sheep. Semen samples were collected from each animal on weekly basis for 52 weeks  with electroejaculator. The sperm morphological characteristics examined were: detached mid-piece and tail (DMT), detached head (DH), mid-piece droplet (MPD, coiled and bent tail (CBT) and acrosomal abnormality (ACR). The semen cation parameters measured were: sodium ion (Na+), potassium ion (K+) and calcium ion (Ca2+). Pearson correlation matrix of SAS was used to determine the relationships among and between the  measured characteristics. The result of the study showed that correlations among the sperm morphological  characteristics were low and not significant except that between DH and DMT which was perfect (p<0.01; r = 1.00). On the other hand, semen cation concentrations were positively correlated but not significant among themselves except the correlation between Na+ and K+ (p<0.01; r = 0.37) which was significant. Relating the semen cation concentration with sperm morphological characteristics, it was discovered that potassium ion (K+) measured was negatively and significantly correlated with all the morphological attributes (DMT & DH, r= -0.36 @ p<0.01; CBT & ACR, r= -0.38 @ p<0.05; MPD, r= -0.32 @ p<0.05). It was concluded that DH is highly associated with DMT while Na+ concentration was an indicator for K+ level in the semen as shown in the result.  Also, the higher the potassium ion in semen, the lower the level of sperm morphological abnormalities and vice versa in Yankasa rams.

Keywords: Sperm morphological characteristics, semen cation concentrations, Yankasa rams