The National Veterinary Institute, Technical University of Denmark, 1870 Frederiksberg C, Copenhagen, Denmark.
J Dairy Sci. 2012 Oct;95(10):5740-9. doi: 10.3168/jds.2012-5470. Epub 2012 Aug 3.
The objective of this study was to assess the epidemiologic and economic consequences of intervention against contagious clinical mastitis during lactation. A bioeconomic model of intramammary infections (IMI) was used to simulate contagious spread of Staphylococcus aureus, Streptococcus uberis, and Streptococcus dysgalactiae, and an environmental spread of Escherichia coli IMI in a 100-cow dairy herd during 1 quota year. The costs of clinical IMI, subclinical IMI, and intervention were calculated into the total annual net costs of IMI during lactation per scenario and compared with a default scenario. Input parameter values were based on the scientific literature. The scenarios were 3-d intramammary lactational treatment (default), 5-d intramammary treatment, 5-d intramammary treatment and 3-d systemic treatment, 3-d intramammary treatment and culling bacteriologically unrecovered clinical IMI cows, and 5-d intramammary treatment and culling bacteriologically unrecovered clinical IMI cows. Sensitivity analysis was conducted on parameter input values. The results showed that interventions including antibiotic treatment combined with culling unrecovered clinical IMI cows resulted in the lowest transmission, number of IMI cases, and persistent subclinical IMI cases. Nonetheless, the high associated costs of culling bacteriologically unrecovered clinical IMI cows made the other scenarios with a long and intensive antibiotic treatment, but without culling, the most cost effective. The model was sensitive to changes to the cure rate of clinical IMI following treatment, but the ranking of the intervention scenarios did not change. The model was most sensitive to the changes to the transmission rate of Staph. aureus. The ranking of the intervention scenarios changed at low transmission rate of this pathogen, in which the default scenario became the most cost-effective scenario. In case of high transmission of contagious IMI pathogens, long and intensive treatment of clinical IMI should be preceded by strategies that lower the transmission.
本研究旨在评估针对哺乳期传染性临床乳腺炎的干预措施的流行病学和经济学后果。使用乳腺感染（IMI）的生物经济模型来模拟金黄色葡萄球菌、无乳链球菌和停乳链球菌的传染性传播，以及大肠杆菌 IMI 在 100 头奶牛牛群中的环境传播在 1 个配种年内。将临床 IMI、亚临床 IMI 和干预的成本纳入每个方案哺乳期内 IMI 的总年度净成本，并与默认方案进行比较。输入参数值基于科学文献。方案为 3 天内乳腺内泌乳期治疗（默认）、5 天内乳腺内治疗、5 天内乳腺内治疗和 3 天内全身治疗、3 天内乳腺内治疗和淘汰细菌学上未恢复的临床 IMI 奶牛，以及 5 天内乳腺内治疗和淘汰细菌学上未恢复的临床 IMI 奶牛。对参数输入值进行了敏感性分析。结果表明，包括抗生素治疗结合淘汰未恢复的临床 IMI 奶牛的干预措施导致传播、感染病例数和持续性亚临床 IMI 病例数最低。尽管淘汰细菌学上未恢复的临床 IMI 奶牛的相关成本较高，但没有淘汰的其他方案中，长时间和密集的抗生素治疗成本效益最高。该模型对治疗后临床 IMI 的治愈率变化敏感，但干预方案的排名没有改变。该模型对金黄色葡萄球菌的传播率变化最敏感。在这种病原体的传播率较低的情况下，干预方案的排名发生变化，默认方案成为最具成本效益的方案。在传染性 IMI 病原体传播率较高的情况下，应在对临床 IMI 进行长期和密集治疗之前采取降低传播的策略。
