Management and control of parasites on dairy farms in northwestern region of São Paulo state

Abstract Dairy cattle farming is of great economic and social importance in all Brazilian’s regions. Parasites can reduce milk productivity, especially the tick Rhipicephalus (Boophilus) microplus. This study consisted of a questionnaire answered by 40 milk producers in the northwestern region of the State of São Paulo. The aim was to ascertain how these producers controlled ticks and other parasites. Very many of them knew nothing about the biological cycle of the cattle tick or about strategic control or acaricide efficacy tests. The majority (87.5%) controlled ticks at a high frequency, without technical criteria and care to apply the acaricide. Spraying was the most used mode of acaricide application (95%) and endectocides were used by 45%. Cattle tick fever was the harm most associated with ticks (87.5%) followed closely by screwworm (77.5%). However, 65% were satisfied with their tick control. About the control of others parasites, all dewormed at least twice a year their animals; 65% were controlling horn fly; 40% had problems with screwworm. The interviewers had in general good level of education and the farms generally exhibited a high degree of technology for milk production on pasture because half of them received technical assistance frequently.

摘要：奶牛养殖在巴西各地区均具备重要的经济与社会价值。寄生虫可降低奶牛产奶性能，其中微小牛蜱（Rhipicephalus (Boophilus) microplus）的负面影响尤为突出。本研究针对圣保罗州西北部地区的40名奶牛养殖户开展问卷调查，旨在明确该群体对牛蜱及其他寄生虫的防控现状。
绝大多数养殖户对牛蜱的生物学周期、策略性防控方案以及杀螨剂（acaricide）效力检测均缺乏认知。87.5%的养殖户会高频次开展牛蜱防控，但未遵循技术规范，且未规范施用杀螨剂。喷雾是最常用的杀螨剂施用方式（占比95%），45%的养殖户使用了体内外驱虫剂（endectocides）。养殖户提及最多的蜱相关危害为牛蜱热（cattle tick fever）（87.5%），其次为旋蝇（screwworm）感染（77.5%）。尽管如此，仍有65%的养殖户对当前的牛蜱防控措施表示满意。
在其他寄生虫防控方面，所有养殖户每年至少为牲畜进行两次驱虫；65%的养殖户开展角蝇（horn fly）防控；40%的养殖户存在旋蝇感染问题。受访养殖户整体受教育水平良好，且半数牧场频繁获得技术援助（technical assistance），因此其牧草饲养模式下的奶牛生产技术水平普遍较高。