PHYTOESTROGEN POISONING IN SHEEP
 
Description    Red clover (TIFOLIUM PRATENSE), Alfalfa (MEDICAGO SATIVA), and Subterranean clover (TRIFOLIUM SUBTERRANEUM) contain phytoestrogens that can cause temporary infertility in ewes grazing at the time of mating or permanent infertility if there is a long history of grazing. Affected ewes fail to cycle and lambing is decreased. Enlarged teats and lactation have been reported in affected rams and wethers. A syndrome of dystocia has also been seen; high levels of dystocia with lambs born dead continued up to 6 months after ewes were removed from the pasture.
 
Species   Ovine
 
Signs   Abnormal length of estrus period, Abortion or weak newborns, Anestrus, Female infertility, Galactorrhea, inappropriate milk production, Swelling mass, vulva, clitoris
 
References   Panter KE. Effects of Xenobiotics and Phytotoxins on Reproduction in Food Animals. Vet Clin N A Food Anim Pract 2011;27:429 [Web Reference]
Evans TJ. Diminished Reproductive Performance and Selected Toxicants in Forages and Grains. Vet Clin N A Food Anim Pract 2011;27:345 [Web Reference]
Palmieri C. Congenital and acquired pathology of ovary and tubular genital organs in ewes: A review. Therio 2011;75:393 [Web Reference]
Copyright © 2017 Cornell University College of Veterinary Medicine