Luteal function and oestrus in gilts treated with a synthetic analogue of prostaglandin F-2 (ICI 79,939) at various times during the oestrous cycle

Abstract

Plasma progesterone concentrations after ICI 79,939 [prostaglandin F2.alpha. analogue] treatment are shown. The use of prostaglandins[PG] alone for estrous synchronization of gilts at various stages of the cycle seems severely limited because of the relatively short period of luteal sensitivity. The importance of luteal age in PGF2.alpha. mediated regression suggests that extension of the luteal phase followed by PGF2.alpha. treatment should be investigated as a method of estrous synchronization in the pig.