Reference

Effects of placement of intravaginal sponges on LH, FSH, estrus and ovarian activity in mares during the nonbreeding season

Effects of placement of intravaginal sponges on LH, FSH, estrus and ovarian activity in mares during the nonbreeding season. Thompson, D. L., Jr.; Reville, S. I.; Derrick, D. J.; Walker, M. P. (Louisiana State Univ., Baton Rouge, LA 70803, USA). J. Anim. Sci., 58(1), 159-64 (English) 1984. CODEN: JANSAG. ISSN: 0021-8812. DOCUMENT TYPE: Journal CA Section: 2 (Mammalian Hormones) Intravaginal insertion of polyurethane sponges in seasonally anestrous mares resulted in surges in FSH [9002-68-0] and LH [9002-67-9] secretion and increased ovary size and activity. Results, however, were variable with only ~50% of animals responding. Although some mares exhibited 1 or more days of estrus after sponge insertion, no mare displayed estrus followed by diestrus. Treatment with intravaginal sponges had no effect on estrus induction by feeding altrenogest [850-52-2]. Evidently, sponge treatment is not suitable for inducing follicular activity in anestrous mares.

Antifertility action of two synthetic progestins in female white-tailed deer

Antifertility action of two synthetic progestins in female white-tailed deer. Matschke, George H. (Denver Fed. Cent., Fish Wildl. Serv., Denver, Colo., USA). J. Wildl. Manage., 41(2), 194-6 (English) 1977. CODEN: JWMAA9. DOCUMENT TYPE: Journal CA Section: 2 (Hormone Pharmacology) Two synthetic progestins, 17.alpha.-acetoxy-6-methyl-16-methylene-4,6-pregnadiene-3,20-dione (MGA) [2919-66-6] and 17.alpha.-allyl-17.beta.-hydroxy-3-oxoestra-4,9,11-triene (DRC 6246) [850-52-2], were fed prior to or for a short time during the breeding season in 3 different feeding regimes to female white-tailed deer (Odocoileus virginianus). Both compds. were well accepted orally, but they did not prevent or delay conception or interfere with pregnancy. No differences were recorded in conception dates or no. of fawns among treatment groups. Apparently, exogenously administered prgestins are not accumulated in sufficient quantities in the body fat to provide prolonged hormonal storage from which target organs are supplied.