Singh Nirbhay Kumar, Vemu Bhaskar, Singh Harkirat, Prerna Mranalini, Daundkar Prashant S, Sharma S K, Dumka V K
Department of Veterinary Parasitology, College of Veterinary Science, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana, 141004, India,
Parasitol Res. 2015 Apr;114(4):1531-9. doi: 10.1007/s00436-015-4337-y. Epub 2015 Jan 31.
Larval packet test was used for detection of resistance status against cypermethrin and deltamethrin, the most commonly used synthetic pyrethroids in Rhipicephalus (Boophilus) microplus collected from Faridkot district, Punjab (India). The slope of mortality, lethal concentration for 50 % (LC50) and resistance levels were determined from the regression graphs of probit mortality of ticks plotted against log values of increasing concentrations of cypermethrin and deltamethrin. Results indicated presence of resistance of levels I and II against cypermethrin (resistance factor (RF) = 2.82) and deltamethrin (RF = 8.44), respectively. Adult immersion test was used to assess the acaricidal activity of aqueous (MLAq), ethanol (MLE), chloroform (MLC), acetone (MLA) and hexane (MLH) extracts of leaves of Murraya koenigii against these synthetic pyrethroid (SP)-resistant engorged adult females of R. (B.) microplus by determination of per cent adult mortality, reproductive index (RI), per cent inhibition of oviposition (%IO) and hatching rate. The per cent mortality caused by various extracts at concentrations ranging from 0.625 to 10.0% varied from 0.0 to 100.0% with maximum per cent mortality of 10.0, 100.0, 70.0, 40.0 and 10.0 recorded against MLAq, MLE, MLC, MLA and MLH, respectively. Among all extracts, the highest acaricidal property against SP-resistant R. (B.) microplus was exhibited by the MLE as it showed the minimum LC50 [95% confidence limit (CL)] values of 2.97% (2.82-3.12%), followed by MLC as 10.26% (8.84-11.91 %) and MLA as 18.22% (16.18-20.52%). The average egg mass weight recorded in live ticks treated with various concentrations of different extracts was lower than the respective control group ticks and was significantly (p < 0.01) lower in ticks treated with MLH extract. However, no significant effect on hatchability of eggs of treated groups when compared to control was recorded. A significant (p < 0.05) decrease in the RI was recorded in MLH extract-treated ticks, and the %IO varied from 0.07 to 34.73% with various extracts and was recorded maximum with highest concentration of MLH. The results of the current study indicate that the extracts of M. koenigii can be used for control of SP-resistant ticks.
幼虫包囊试验用于检测微小牛蜱对氯氰菊酯和溴氰菊酯的抗性状态，这两种是从印度旁遮普邦法里德果德地区采集的微小牛蜱中最常用的合成拟除虫菊酯。根据蜱虫的概率死亡率与氯氰菊酯和溴氰菊酯浓度对数增加的回归图，确定死亡率斜率、50%致死浓度（LC50）和抗性水平。结果表明，微小牛蜱对氯氰菊酯（抗性因子（RF）=2.82）和溴氰菊酯（RF=8.44）分别存在I级和II级抗性。成蜱浸泡试验用于评估九里香叶的水提取物（MLAq）、乙醇提取物（MLE）、氯仿提取物（MLC）、丙酮提取物（MLA）和己烷提取物（MLH）对这些合成拟除虫菊酯（SP）抗性的饱血成年微小牛蜱雌虫的杀螨活性，通过测定成虫死亡率百分比、生殖指数（RI）、产卵抑制百分比（%IO）和孵化率来评估。浓度范围为0.625%至10.0%的各种提取物引起的死亡率百分比在0.0%至100.0%之间变化，MLAq、MLE、MLC、MLA和MLH分别记录到的最高死亡率百分比为10.0%、100.0%、70.0%、40.0%和10.0%。在所有提取物中，MLE对SP抗性微小牛蜱表现出最高的杀螨性能，因为它显示出最低的LC50[95%置信区间（CL）]值为2.97%（2.82 - 3.12%），其次是MLC为10.26%（8.84 - 11.91%）和MLA为18.22%（16.18 - 20.52%）。用不同提取物的各种浓度处理的活蜱中记录的平均卵块重量低于各自对照组的蜱，并且用MLH提取物处理的蜱显著更低（p<0.01）。然而，与对照组相比，未记录到对处理组卵孵化率的显著影响。在MLH提取物处理的蜱中记录到RI显著（p<0.05）下降，并且不同提取物的%IO在0.07%至34.73%之间变化，在MLH最高浓度时记录到最大值。当前研究结果表明，九里香提取物可用于控制SP抗性蜱。
