Effects of Graded Levels of Bentonite on Serum Clinical Profiles, Metabolic Hormones, and Serum Swainsonine Concentrations in Lambs Fed Locoweed (Oxytropis sericea)'

samples were collected 1, 2, 4, and 8 h after feeding. Weekly blood samples were analyzed for serum clinical chemistry profiles, and additional blood samples collected on d 35 were analyzed for serum metabolic hormones and serum swainsonine concentrations. Within 1 wk, serum alkaline phosphatase and glutamic oxaloacetic transaminase activities increased markedly (P < .05) in lambs fed locoweed. Serum insulin, growth hormone, and prolactin concentrations were not affected by feeding locoweed, but serum triiodothyronine and thyroxine concentrations were decreased by approximately 50% (P < .05) in lambs fed locoweed. Serum swainsonine concentrations were not detected in lambs fed the positive control diet and ranged from 144 to 235 ng/mL in lambs fed locoweed. Overall, serum profiles, metabolic hormone concentrations, and serum swainsonine concentrations indicated that the bentonite (up to 42 g daily) was ineffective in alleviating locoweed toxicosis.