Effect of locoweed (Astragalus ientiginosus) feeding of fetal lamb development.

Locoweed, Astragalus lentiginosus, was fed to pregnant ewes for various periods during gestation. The principal gross effects on the developing fetuses were observed to be delayed placentation, decreased vascularization, fetal edema and hemorrhage, and alteration of cotyledon development. Deformed lambs and undersized lambs also occurred. Data from sheep fed locoweed during various periods of the entire gestation period are summarized and indicate that locoweed poisoning in the fetus as with the adult is a chronic type of intoxication. Also, poisoning of the fetus parallels poisoning in the dam.