Submitted to: Journal of Animal Science Supplement
Publication Type: Abstract Only
Publication Acceptance Date: January 30, 2002
Publication Date: December 20, 2002
Citation: Vallet, J.L. 2002. The effect of progesterone treatment on day 2 and 3 of pregnancy on gestation length, litter size, birth weight, and piglet growth rate in intact white crossbred pigs [abstract]. Journal of Animal Science. 80(Supplement 2):83. (Abstract No. 208) Technical Abstract: Previous results indicated that treatment of unilaterally hysterectomized- ovariectomized white crossbred gilts on d 2 and 3 of pregnancy with exogenous progesterone increased fetal weights at 105 d of gestation and decreased uterine capacity. Because the incidence of stillbirths is associated with underweight piglets, the objective of the current experiment was to determine whether early progesterone treatment could be used to decrease the number of stillborn pigs per litter in intact white crossbred gilts. Gilts were mated at estrus and received either no treatment (n=78) or progesterone injection (200 mg/d, i.m.; n=34) on d 2 and 3 of pregnancy. Gilts were then allowed to farrow and gestation length, number of fully formed piglets, number born alive, and birth weights were recorded. Piglets were weighed again at weaning (approximately 21 d) and at approximately 56 d of age. Progesterone-treated gilts did not differ from control-treated gilts in the number of piglets born alive or stillborn piglets per litter. Progesterone treatment shortened (P=0.05) gestation length (115.47+/-0.21) compared to control (115.97+/-0.14). Piglets born to progesterone-treated gilts did not differ from control gilts in birth weights, weaning weights or weights at 56 d of age. These results indicate that early progesterone treatment shortens gestation length but has no effect on litter size in intact pigs. Furthermore, progesterone treatment does not affect birth weights of the piglets, the number of stillborn piglets or the subsequent growth rates of piglets born alive.