The influence of quality of the semen of the boars on the sows` fecundation and the size of litter

The aim of this master`s thesis was to analyze how the quality of the boar‘s semen affects sows‘ fecundation and their size of litter that was born. The work has been done in the year 2016 – 2017 at the Animal Reproduction Laboratory of Veterinary Academy of Lithuanian University of Health Sciences. There were examined 38 doses of fresh diluated semen of the boars. As well, by using good quality semen there were received and analyzed the fecundation data such as fecundation and the size of the litter of the 429 sows. The quality of the semen has been rated at the laboratory. The motility of the spermatozoas has been evaluated at the time the semen was collected and after 24, 48 and 72 hours of incubation at the temperature +16°C. The concentration of spermatozoas has been measured using the hemocytometer camera. Pathological spermatozoas‘ heads have been evaluated by coloring smears using SpermBlue stain, while the pathological tails have been evaluated by dilution of formalin and calculating the percentage of each pathology. For dilution of sperm, a diluent for long storage of Vitasem has been used by which diluting the semen can be used for insemination for 4-5 days. The sows used for research were inseminated on the first, second, third and fourth days of the semen storage. The largest motility of the spermartozoas has been measured only in the fresh semen of boars (68,16 ± 13,23 %.). The average concentration of the semen was 3.14 billion in a dose, while the concentration of the motile spermatozoas was 2.09 billion in a dose. The foundings have shown that the higher concentration of the spermatozoas is and the more pathological spermatozoas are in a dose, the lower motility of the spermatozoas is (p 0.05)