Effect of season on characteristics of red deer /Cervus elaphus L./ semen collected using modified artificial vagina.

During three reproductive seasons, 572 ejaculates were collected from five farmed red deer stags using a modified artificial vagina. The ejaculates were evaluated in terms of their quality and quantity by standard procedures applied for domestic animals. The total length of sexual activity was 245 days, from August 4 to April 6. Significant changes in the semen parameters were noted over this period, divided into three stages: pre-mating, mating, post-mating. During mating season the following values of sperm parameters were recorded: 1/ volume of white and yellow fractions -0.18 and 2.03 ml, respectively; 2/ pH of white and yellow fraction -6.80-7.41 and 6.65-7.45, respectively; 3/ sperm concentration -2.27 mln/mm3; 4/ sperm motility -47% (with 80% of them showing steady progressive motion at moderate speed); 5/ duration of sperm motility -6 hours 39 minutes, and 6/ low percentage of major and minor sperm defects (<5% and <10%, respectively). In summary, measures of semen quality including fraction volume, pH, sperm concentration and sperm motility change gradually during the pre-mating, mating and post-mating seasons of red deer. The period of greatest libido (from the end of September until the end October) coincides with highest semen quality.