Resumen de Un estudio comparativo de las subpoblaciones espermáticas en moruecos de alta y baja fertilidad en campo

J.L. Yániz, Inmaculada Palacín, S. Vicente Fiel, J.A. Sánchez, P Santolaria

• The aim of the present study was to investigate whether differences in field fertility of rams are reflected in differences in sperm morphometric and kinematic population structure. The association between sperm morphometric and kinematic subpopulations was also investigated. Ejaculates from 8 adult rams, 4 with high and 4 with low field fertility, were collected weekly using an artificial vagina over 6 consecutive weeks. Analyses of sperm motility using computer-assisted sperm analysis (CASA) and sperm nuclear morphometry using computer-assisted sperm morphometry-fluorescence were performed. Clustering procedures using the kinematic and morphometric data from high and low field fertility rams resulted in the classification of spermatozoa in three kinematic and three morphometric sperm subpopulations. The distribution of subpopulations between rams of high and low field fertility was significantly different, with higher percentages of spermatozoa exhibiting fast and linear movements and those with large and long nuclei in the high fertility group. However, these subpopulations were not correlated. It was concluded that high and low fertility rams present clear differences in sperm population structure.