Evaluation of hepatic changes and weight gains in sheep grazing Kochia scoparia

Sixteen Western Whiteface ewes were divided into 2 groups to determine the effects of plant maturity on liver function and weight gains. They were all owed to graze a greater than 95% pure stand of Kochia scoparia for 72 or 55 d. Four additional sheep (controls) were placed on weedy Bermuda grass pas ture with the same water supply as the kochia-fed sheep. Body weights were determined on June 5, 1996 and on removal from the kochia pasture. Blood sa mples were collected at approximately 7-d intervals for serum chemistry pro files. Kochia scoparia plant samples were also randomly collected at 5-6 w intervals, oven dried, identified by date of collection and stored for late r nutrient, oxalate, nitrate and sulfate analysis. Liver biopsies were perf ormed pre-, mid- and post-study to assess morphologic changes. An almost ex clusive diet (>95%) of Kochia scoparia resulted in minimal elevations in se rum GGT, suggesting mild hepatocellular injury, but was not associated with overt hepatic lesions or clinical disease. Other serum chemistry measureme nts were within normal ranges. Unlike for other domestic animal species, Ko chia scoparia may be a useful grazing forage for sheep, offering little ris k of toxicosis.