86 Effects of feeding an alkaloid binder on nutrient digestibility, alkaloid recovery in feces and performance of lambs fed diets contaminated with cereal ergot.

As contamination with cereal ergot has been increasing in Western Canada, a study was conducted to evaluate impacts of feeding an alkaloid binder (Biomin® II) on nutrient digestibility, alkaloid recovery in feces and lamb growth performance. Forty-eight ram lambs (25.9 + 1.4 kg) were randomly assigned to one of four barley-based diets: Control (C), no added alkaloids, Control +binder fed at 30 g/hd/d (CB); Ergot, 2564 ppb total R + S epimers (E); Ergot + binder, 2534 ppb epimers and alkaloid binder (EB). Lambs were individually fed ab libitum for up to 10 wks until slaughter at > 46 kg LW. Both ADG and gain: feed were greater (P < 0.05) for lambs fed C and CB diets as compared to those contaminated with ergot. Serum prolactin concentrations were 1.73 X increased in EB as compared to E-fed lambs (P < 0.01) although both were lower than those of lambs fed C or CB (P < 0.001). Rectal temperatures of E lambs were greater (P = 0.002) than those receiving other diets. In a digestibility study using 8 ram lambs, NDF digestibility was 11% reduced (P = 0.003) for E compared to other treatments. Nitrogen retention was 18.8% greater (P < 0.05) for lambs receiving control compared to ergot-contaminated diets. Evaluating feces for R epimers, EB lambs had 30.6% greater (P < 0.001) fecal alkaloid recovery compared to those fed E. Based on the sparing effect on prolactin and reduced body temperature, binder may mitigate impacts of ergot alkaloids by directing more of these toxins into feces. Alkaloid concentration in E and EB diets were at limits allowed in feeds for sheep in Canada. Future studies will be required to determine if greater dietary concentrations of binder can also mitigate negative impacts of alkaloids on nitrogen retention and animal performance.