9. Dynamics of morphofunctional parameters of ram sperm – breed synthetic population Bulgarian dairy depending on season and individual characteristics

Author: Rossen Stefanov, Elena Kistanova, Nikola Metodiev, Dimitrina Kacheva, Emilia Raicheva, Boyko Georgiev, Paulina Taushanova

DOI: n/a


The analysis of the ejaculates of a sire is a crucial for the selection of individuals in terms of their reproductive qualities. This analysis includes functional characteristics of sperm: motility and activity of key enzymes (LDH, GGT) as well as the morphological parameters of male gametes. The aim of this study was to determine how the season and consecutive of ejaculate affect morphofunctional parameters of ram sperm from the breed Synthetic Population Bulgarian Dairy. In the experiments five clinically healthy rams were used. There were obtained three consecutive ejaculates for each sire in three seasons – spring, summer and autumn. For the estimation of sperm motility and morphological parameters the Sperm Class Analyzer (Microptic Systems) was used. The biochemical activities of the enzymes LDH and GGT were determined by spectrophotometer – Mindrai BA 88. During the spring period in all ejaculate decreasing of the sperm quality in terms of sperm motility, was observed as well as the activity of tested enzymes. At the same time higher percentage of sperm with morphological abnormalities was observed. Ejaculates with good values of studied parameters were obtained from experiments in summer and autumn. Divergence in the quality of the ejaculates is more expressive between different sire, than between consecutive ejaculates of one sire. Individuals with high values of the studied parameters keep them in all consecutive ejaculates. The obtained results allow concluding that the quality of sperm depends more on the season than on the consecution of ejaculate.