Trials of rut induction with prostaglandin F2alpha in gilts

The possibility of oestrus induction by means of F-2-alpha prostaglandin was checked on nine gilts. The animals received intramuscular injections of 7.5 mg of 10 mg of PG F2alpha on the tenth or twelfth day of cycle. The sexual behaviours of the animals was followed up, and after slaughter followed macroscopic assessment of the ovaries as well as histomorphological and histochemical examinations of the uterus wall. The results have shown that no oestrus or ovulation could be induced by such injection on the tenth or twelfth day of cycle. Regression of corpora lutea and follicle growth five days following application on the twelfth day of cycle were somewhat faster than the same phenomena when observed following injection on the tenth day. However, oestrus and ovulation failed throughout to occur earlier than they would have occurred any way without any treatment. The cycle was not shortened by application of F-2-alpha prostaglandin.