title: Retention rate in cows and heifers of intravaginal silastic coils impregnated with progesterone.
mesh_terms: D000818:Animals; D002417:Cattle; D004343:Drug Implants; D004973:Estrus Synchronization / Q000187:drug effects*; D005260:Female; D011247:Pregnancy; D011374:Progesterone / Q000008:administration & dosage* / Q000097:blood / Q000378:metabolism; D012826:Silicone Elastomers; D013193:Stainless Steel; D014621:Vagina
chemical_list: D004343:Drug Implants; D012826:Silicone Elastomers; D013193:Stainless Steel; D011374:Progesterone