Addressing neonatal diarrhea and antibiotic use in dairy calves

解决奶牛犊的新生儿腹泻和抗生素使用问题

• 批准号: 487074-2015
• 负责人: Weese, Scott
• 金额: $ 1.82万
• 依托单位: University of Guelph
• 依托单位国家: 加拿大
• 项目类别: Engage Grants Program
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=585925
• 关键词: Addressing; neonatal; diarrhea; antibiotic; use

The dairy industry is an important economic sector in Canada, and animal health greatly influences economic performance. Diarrhea is a common problem in dairy calves, and while a variety of bacterial (e.g. E. coli, Salmonella), viral (e.g. rotavirus) and parasitic (e.g. Cryptosporidium) causes have been well-studied, the cause of diarrhea is often not diagnosed and outbreaks on farms are not uncommon. Difficulties diagnosing (and preventing) diarrhea could be because of interactions between microorganisms (coinfections); disease that occurs as a result of microbial population disturbances, not the effects of sole organisms ('dysbiosis'), changes in disease patterns of known pathogens or emergence of new pathogens or strains. This study will involve a large dairy operation in Ontario that produces approximately 750 calves per year. Despite modern management practices and exceptional production of milk and high quality genetics, calf diarrhea rates have been very high. In 2014, 92% of calves were treated for diarrhea. Calf mortality was 5%, with rates reaching 25% at some points during the year. Extensive diagnostic testing has failed to implicate the 'traditional' calf diarrhea pathogens and preliminary evaluation of farm records indicates a very high incidence of antibiotic use, resulting in high economic costs, high labour costs for administration and concerns about risks for development of antimicrobial resistance. This study will evaluate the cause of diarrhea on this farm, as a way to improve calf health and economic production on the farm, as well as to provide a broader understanding of this industry-wide problem. It will do so by using novel techniques to evaluate the composition of the bacterial population in the intestinal tract (the 'microbiota') as well as specific targeting of bovine coronavirus based on preliminary data suggesting this virus is present at high rates in diarrheic calves compared to healthy controls. It will also develop and test an antimicrobial use algorithm to standardize and improve antibiotic administration, to improve treatment of calves and reduce antibiotic use (thereby optimizing calf health and reducing the likelihood of antibiotic resistance.)

乳制品行业是加拿大重要的经济部门，动物健康对经济表现有很大影响。腹泻是犊牛常见的问题，而各种细菌（如E.大肠杆菌、沙门氏菌属）、病毒（如轮状病毒）和寄生虫（如隐孢子虫）引起的腹泻已得到充分研究，腹泻的原因往往无法诊断，在农场爆发并不罕见。诊断（和预防）腹泻的困难可能是由于微生物之间的相互作用（合并感染）;由于微生物群失调而发生的疾病，而不是单一生物体的影响（“生态失调”），已知病原体的疾病模式变化或新病原体或菌株的出现。本研究将涉及安大略的一个大型奶牛场，该奶牛场每年生产约750头小牛。尽管有现代化的管理实践和卓越的牛奶生产和高质量的遗传，小牛腹泻率一直很高。 2014年，92%的小牛接受了腹泻治疗。小牛死亡率为5%，在这一年的某些时候达到25%。广泛的诊断检测未能发现“传统”小牛腹泻病原体，对农场记录的初步评估表明抗生素使用率非常高，导致经济成本高，管理劳动力成本高，并担心抗生素耐药性发展的风险。这项研究将评估该农场腹泻的原因，作为改善农场小牛健康和经济生产的一种方式，并提供对这一全行业问题的更广泛理解。它将通过使用新技术来评估肠道中细菌种群（“微生物”）的组成以及基于初步数据的牛冠状病毒的特异性靶向来做到这一点，这些数据表明，与健康对照组相比，这种病毒在腹泻小牛中的发病率很高。它还将开发和测试抗菌剂使用算法，以标准化和改善抗生素管理，改善小牛治疗并减少抗生素使用（从而优化小牛健康并降低抗生素耐药性的可能性）。