Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium.
Vet Parasitol. 2012 Mar 23;184(2-4):204-11. doi: 10.1016/j.vetpar.2011.09.008. Epub 2011 Sep 12.
Subclinical infections with gastrointestinal nematodes and liver fluke are important causes of production losses in grazing cattle. Although there is an extensive compilation of literature describing the effect of these infections on animal performance, only a few attempts have been made to convert these production losses to an economic cost. Here, we propose a novel tool (ParaCalc(®)), available as a web-application, to provide herd-specific estimates of the costs of these infections on dairy farms. ParaCalc(®) is a deterministic spread-sheet model where results from diagnostic methods to monitor the helminth infection status on a herd and anthelmintic usage are used as input parameters. Default values are provided to describe the effects of the infections on production and the cost of these production losses, but the latter can be adapted to improve the herd-specificity of the cost estimate. After development, ParaCalc(®) was applied on input parameters that were available for 93 Belgian dairy herds. In addition, the tool was provided to 6 veterinarians and their user experiences were evaluated. The estimated median [25th-75th percentile] cost per year per cow was € 46 [29-58] and € 6 [0-19] for gastrointestinal nematode and liver fluke infection, respectively. For both infections, the major components in the total costs were those associated with milk production losses in the adult cows. The veterinarians evaluated ParaCalc(®) as a useful tool to raise the farmers' awareness on the costs of worm infections, providing added value for their services. However, the score given for user-friendliness was diverse among users. Although the model behind ParaCalc(®) is a strong simplification of the real herd processes inducing economic losses, the tool may be used in the future to support economic decisions on helminth control.
胃肠道线虫和肝吸虫的亚临床感染是放牧牛生产损失的重要原因。尽管有大量文献描述了这些感染对动物性能的影响，但很少有人试图将这些生产损失转化为经济成本。在这里，我们提出了一种新的工具（ParaCalc（®）），它是一个网络应用程序，可提供奶牛场这些感染对经济效益影响的特定畜群估计。ParaCalc（®）是一个确定性的电子表格模型，其中用于监测畜群中寄生虫感染状况和驱虫药使用的诊断方法的结果作为输入参数。提供了默认值来描述感染对生产的影响以及这些生产损失的成本，但可以对后者进行调整，以提高成本估计的畜群特异性。ParaCalc（®）开发完成后，我们应用了 93 个比利时奶牛场的可用输入参数。此外，还向 6 位兽医提供了该工具，并评估了他们的用户体验。估计的每头奶牛每年的中位数[25%至 75%分位数]成本分别为 46 欧元[29-58 欧元]和 6 欧元[0-19 欧元]，用于治疗胃肠道线虫和肝吸虫感染。对于这两种感染，总费用的主要组成部分是成年奶牛产奶损失相关的费用。兽医们认为 ParaCalc（®）是提高农民对蠕虫感染成本意识的有用工具，为他们的服务增加了附加值。然而，用户对用户友好性的评分存在差异。尽管 ParaCalc（®）背后的模型是对导致经济损失的真实畜群过程的强有力简化，但该工具将来可能用于支持对驱虫控制的经济决策。
