Study of the relationship between the age of the rams and the quality of their ejaculates obtained outside the breeding season

The present study aims to research the effect of age on the quality of ejaculates of rams from Synthetic population of Bulgarian dairy breed. Rams divided into two age groups were used for the experiment: G1 (2.5 years) versus G2 (6 years). Ejaculates were obtained by the method of artificial vagina and diluted with medium 6A-G. The tested ejaculates were obtained outside the breeding season. A Sperm Class Analyzer (SCA Microptic, Barcelona, Spain) was used to study sperm motility. The biochemical activity of the enzymes lactate dehydrogenase (LDH) and gamma-glutamyl transferase (GGT) was determined using an automatic Mindrai BA88 spectrophotometer. The activity of the enzymes was studied in sperm plasma, in aqueous and tritonic extract. Significant differences between the groups were found in total sperm motility (P≤0.05) and LDH enzyme activity in sperm plasma (P≤0.01). Regarding the efficiency of the LDH enzyme in aqueous and tritone extract, no significant differences between the groups was found. No significant differences were found between groups for GGT activity, while age had significant impact on LDH enzyme in sperm plasma.