Department of Ecosystem and Public Health, University of Calgary, Calgary, AB, Canada.
Department of Production Animal Health, University of Calgary, Calgary, AB, Canada.
Prev Vet Med. 2021 Apr;189:105297. doi: 10.1016/j.prevetmed.2021.105297. Epub 2021 Feb 23.
Johne's disease (JD), or paratuberculosis, is an infectious disorder primarily associated with cattle and sheep and resulting in significant economic losses for dairy producers. The dairy cattle herd-level prevalence in Canada has recently been estimated to be greater than 40%, but the willingness to pay for JD control practices such as testing-and-culling and vaccination among Canadian dairy producers is unknown. This study used confidential cost-of-production data from the Canadian Dairy Commission to develop a Canadian dairy production model incorporating feed, land, labor, and machinery. A second dataset from a nationally distributed questionnaire (closed in March 2020) was used to estimate individual dairy producer valuations of the reduced per-cow cost of milk production that would result from JD control. This is a novel application of compensating variation and equivalent variation (CV and EV), with dairy producers framed as consumers of production inputs and milk output as a proxy for utility. Assuming a within-herd prevalence of 12.5% and a 50% reduction of that prevalence over 10 years, it was estimated JD control has an annual value of CA$28 per cow for the average Canadian dairy producer. Within-herd prevalence, the effectiveness of control at reducing within-herd prevalence, and the time required to achieve that reduction were identified as important factors. With the same assumption of 12.5% within-herd prevalence but with 100% reductions in that prevalence, estimated values ranged from over CA$55 to over CA$90 per cow per year depending on the timeframe of the control program. When assuming a 10-year period required to achieve control, the estimated values exceeded CA$90 per cow per year in various scenarios for herds with higher within-herd prevalence (greater than 20%).
约翰氏病（JD）或副结核病，是一种主要与牛和羊相关的传染病，给奶农造成了重大经济损失。最近估计加拿大奶牛群的流行率大于 40%，但加拿大奶农对 JD 控制措施（如检测和淘汰以及接种疫苗）的支付意愿尚不清楚。本研究使用加拿大乳业委员会的机密生产成本数据，开发了一个包含饲料、土地、劳动力和机械的加拿大奶牛生产模型。第二项数据来自全国分发的问卷调查（2020 年 3 月结束），用于估计单个奶牛生产者对 JD 控制导致的每头奶牛牛奶生产成本降低的估值。这是补偿变化和等效变化（CV 和 EV）的新应用，将奶牛生产者视为生产投入和牛奶产量的消费者，以代表效用。假设群内流行率为 12.5%，并在 10 年内降低 50%，则估计 JD 控制对加拿大普通奶牛生产者的价值为每头牛每年 28 加元。群内流行率、控制降低群内流行率的效果以及实现该降低所需的时间被确定为重要因素。在假设群内流行率为 12.5%，但流行率降低 100%的情况下，根据控制计划的时间框架，估计值范围从每年每头牛超过 55 加元到超过 90 加元不等。当假设需要 10 年才能实现控制时，在流行率较高（大于 20%）的牛群的各种情况下，估计值每年每头牛超过 90 加元。
