[The effect of Oestrophan Spofa (synthetic analog of prostaglandin F2 alpha) added to the insemination dose on pregnancy and fertility in sows].

Laboratory trials were conducted to study the effect of various concentrations of cloprostenol on the motility and morphological changes of the acrosomes of boar spermatozoa. As found, a cloprostenol concentration of 250 ng per ml of semen to 2500 ng per ml of diluted semen has no adverse effect on the motility of spermatozoa and on the morphological changes of their acrosomes. The concentration of 5000 ng of cloprostenol (in the Oestrophan Spofa product) per 1 ml of diluted semen negatively influences the motility of spermatozoa. An insemination dose of 100 ml of diluted sperm treated with 500 ng of cloprostenol was used for the artificial insemination of 152 sows; 166 sows of the same farm inseminated with untreated semen were used as controls. No gilts were included in the trial. Out of the 152 test sows, 113 conceived after the first insemination, i.e. 74.35%, and the average litter size was 10.04 piglets. In the control group, 125 sows delivered their litters, i.e. 75.30% of the total number, the average litter size being 9.96 piglets. Comparing the reproduction parameters of the experimental and control groups it can be said that the treatment of an insemination dose with 500 ng of cloprostenol immediately before insemination had no influence on the pregnancy rate and on the size of litters.