Effects of Continuously Feeding Diets Containing Cereal Ergot Alkaloids on Nutrient Digestibility, Alkaloid Recovery in Feces, and Performance Traits of Ram Lambs

Toxins

John McKinnon¹  Barry Blakley²  Alexandre V. Chaves³  Stephanie Coufal-Majewski³  Kim Stanford⁴  Mary Lou Swift⁵  Tim McAllister⁶  Yuxi Wang⁶ 

[1] Department of Animal Science, University of Saskatchewan, Saskatoon, SK S7N 5B4, Canada;Department of Veterinary Biomedical Sciences, University of Saskatchewan, Saskatoon, SK S7N 5B4, Canada;Faculty of Science, School of Life and Environmental Sciences, University of Sydney, Sydney, NSW 2006, Australia;Livestock Research Section, Alberta Agriculture and Forestry, Lethbridge, AB T1J 4V6, Canada;Ruminant Nutrition, Hi-Pro Feeds, Okotoks, AB T1S 1A2, Canada;Science and Technology Branch, Agriculture and Agri-Food Canada, Lethbridge, AB T1J 4B1, Canada;

关键词: ergot;    alkaloid;    epimer;    growth;    lambs;    nutrient digestibility;   

DOI  :  10.3390/toxins9120405

来源: DOAJ

【 摘 要 】

Allowable limits for cereal ergot alkaloids in livestock feeds are being re-examined, and the objective of this study was to compare nutrient digestibility, growth performance and carcass characteristics of ram lambs fed a range of alkaloid concentrations, including the maximum currently allowed in Canada (2 to 3 ppm). Four pelleted diets were fed: control, with no added alkaloids; 930; 1402; and 2447 ppb alkaloids based on total R and S epimers. Eight ram lambs (30.0 ± 3.1 kg) were used to examine the impacts of dietary treatments on nutrient digestibility and alkaloid recovery from feces. Concentrations of dietary alkaloids evaluated did not affect nutrient digestibility or N metabolism. Excepting ergocornine and ergocryptine, recovery of alkaloids in feces varied among periods, suggesting that individual lambs may differ in their ability to metabolize ergocristine, ergometrine, ergosine, ergotamine and their S epimers. In a second experiment, ram lambs (n = 47, 30 ± 8 kg) were randomly assigned to a diet and weighed weekly until they achieved a slaughter weight of ≥ 45 kg (average 9 weeks; range 6 to 13 weeks). Intake of DM did not differ (p = 0.91) among diets, although lambs fed 2447 ppb alkaloids had a lower (p < 0.01) ADG than did lambs receiving other treatments. The concentration of serum prolactin linearly declined (p < 0.01) with increasing alkaloids. Feeding 2447 ppb total alkaloids negatively impacted growth, while feeding 1402 ppb did not harm growth performance, but reduced carcass dressing percentage. Due to different concentrations of alkaloids affecting growth and carcass characteristics in the present study, determining allowable limits for total dietary alkaloids will require a better understanding of impacts of alkaloid profiles and interactions among individual alkaloids.

【 授权许可】

Unknown