背景:吡虫啉/氯菊酯项圈(Seresto®)先前被证明可以预防犬巴贝虫感染,由网状皮肤传播,在狗长达1个月后应用。本研究评估了在8个月的有效期内预防传播的情况。
方法:将8只动物随机分为第1组(阴性对照)和第2组(Seresto®项圈),分别。第2组中的动物在第0天接受Seresto®项圈。从第2个月到第8个月每月进行滴答挑战。评估标准包括激发后48小时的原位蜱计数,聚合酶链反应(PCR)分析和免疫荧光测定(IFA)。每当狗被诊断出患有巴贝斯虫病时,它们都会被“抢救治疗”,排除并替换。因此,在对照组的整个研究中的不同时间点引入24只替代动物;因此在研究终止时,在后一组中可获得总共32只狗的数据。
结果:原位计数的杀螨效力在第30天为93%,此后为97-100%。在任何时间在任何Seresto®处理的狗中都没有检测到犬只B.canis特异性DNA或抗体。每次攻击后,在8只对照犬的2-6只中检测到犬巴贝斯虫特异性DNA和抗体,确认挑战模型的有效性。
结论:Seresto®项圈在长达8个月的时间内对网状D.ticleatus蜱的挑战非常有效。在此期间的高持续杀螨功效阻止了犬芽孢杆菌的传播,从而在这个实验感染模型中充分保护狗免受感染。
BACKGROUND: An imidacloprid/flumethrin collar (Seresto®) was previously shown to prevent infection with Babesia canis, transmitted by Dermacentor reticulatus, in dogs for up to 1 month after application. The present
study evaluated the prevention of transmission throughout the claimed efficacy period of 8 months.
METHODS: Eight animals each were randomly included in groups 1 (negative control) and 2 (Seresto® collar), respectively. Animals in group 2 received the Seresto® collar on Day 0. Tick challenges were performed monthly from the 2nd to the 8th month. Assessment criteria included in situ tick counts 48 hours post-challenge, polymerase chain reaction (PCR) analyses and immunofluorescence assays (IFA). Whenever dogs were diagnosed with babesiosis they were \"rescue-treated\", excluded and replaced. Consequently, 24 replacement animals were introduced at various time points throughout the
study in the control group; thus data for a total of 32 dogs were available in the latter group at
study termination.
RESULTS: Acaricidal efficacy for in situ counts was 93% on Day 30, and ranged from 97 to 100% thereafter. No B. canis specific DNA or antibodies were detected in any Seresto®-treated dog at any time. Babesia canis-specific DNA and antibodies were detected in 2-6 of 8 control dogs after each challenge, confirming the validity of the challenge model.
CONCLUSIONS: The Seresto® collar was highly effective against challenges with D. reticulatus ticks for up to 8 months. The high sustained acaricidal efficacy over this period prevented transmission of B. canis, thus fully protecting dogs against infection in this experimental infestation model.