Induction of luteinizing hormone surge by pulsatile administration of gonadotropin-releasing hormone analogue in cows with follicular cysts.

LH release in response to pulsatile administration of small amounts of GnRH analogue in cows with follicular cysts was examined. The pulsatile administration of GnRH analogue induced a LH-surge like peak over 10 hr in both normal cows and cows with follicular cysts. The mean peak value of LH in follicular cystic cows did not differ significantly from that of normal cows. All the cows with cysts resumed normal estrous cycles with ovulations within 3 weeks of this treatment. These results suggest that the function of the anterior pituitary for LH release in response to GnRH analogue is not abnormal in cows with follicular cysts, and that cystic cows recover to normal conditions after the pulsatile administration of GnRH analogue.