da Silva Jenevaldo Barbosa, Rangel Charles Passos, de Azevedo Baêta Bruna, da Fonseca Adivaldo Henrique
Faculdade de Ciências Agrárias e Veterinárias-UNESP, Rod. Carlos Tonanni, km 05, Jaboticabal, São Paulo, 14870-000, Brazil,
Exp Appl Acarol. 2014 Aug;63(4):551-7. doi: 10.1007/s10493-014-9793-z. Epub 2014 Apr 4.
This study aimed to evaluate season, breed, number of lactations and milk production as risk factors relating to Rhipicephalus microplus infestation in dairy cows during the peripartum. Eighty-four animals were randomly selected through proportional stratified sampling. All engorged and partially engorged female R. microplus specimens measuring 4.5-8.0 mm were counted during the 5 weeks before calving, calving week and 5 weeks after calving. The peripartum had a significant effect [calving (p < 0.05; prevalence ratio (PR)= 3.12) and post calving (p < 0.05; PR = 2.02)] on R. microplus infestation. Although the average tick count was higher during the rainy season than during the dry season, there was no significant difference (p = 0.055; PR = 0.63). The average R. microplus count was significantly higher (p < 0.05; PR = 2.10) in Bos taurus animals, followed by F1 (p < 0.05; PR = 1.64) and Girolando (p < 0.05; PR = 1.39). The average R. microplus count was significantly higher (p < 0.05; PR = 0.97) in first-lactation animals, followed by those at the second, third and, fourth or subsequent lactation. Milk production showed a negative correlation with R. microplus count, such that high-production animals were significantly (p = 0.003; PR = 2.04) more vulnerable to infestation than were low-production animals. First-lactation and high-production B. taurus animals had greatest vulnerability to R. microplus infestation over the peripartum period, and constituted the at-risk group in the dairy herd.
本研究旨在评估季节、品种、泌乳次数和产奶量作为围产期奶牛微小扇头蜱感染相关风险因素的情况。通过按比例分层抽样随机选取了84头动物。在产犊前5周、产犊周和产犊后5周期间，对所有体长4.5 - 8.0毫米的饱血和部分饱血的微小扇头蜱雌虫进行计数。围产期对微小扇头蜱感染有显著影响[产犊时（p < 0.05；患病率比（PR）= 3.12）和产后（p < 0.05；PR = 2.02）]。尽管雨季的蜱虫平均计数高于旱季，但差异不显著（p = 0.055；PR = 0.63）。娟姗牛的微小扇头蜱平均计数显著更高（p < 0.05；PR = 2.10），其次是F1代（p < 0.05；PR = 1.64）和吉罗兰多牛（p < 0.05；PR = 1.39）。头胎动物的微小扇头蜱平均计数显著更高（p < 0.05；PR = 0.97），其次是二胎、三胎以及四胎或更高胎次的动物。产奶量与微小扇头蜱计数呈负相关，即高产动物比低产动物更容易受到感染（p = 0.003；PR = 2.04）。头胎和高产的娟姗牛在围产期对微小扇头蜱感染的易感性最高，是奶牛群中的高危群体。
