Desena M L, Clark J M, Edman J D, Symington S B, Scott T W, Clark G G, Peters T M
Department of Entomology, University of Massachusetts-Amherst 01003, USA.
J Med Entomol. 1999 Nov;36(6):811-23. doi: 10.1093/jmedent/36.6.811.
Gas chromatography with flame-ionization detection was used to measure the time-associated, quantitative changes in the cuticular hydrocarbons of female Aedes aegypti (L.). Cohorts of unstressed Ae. aegypti, Rockefeller strain, were reared and held at 3 constant temperatures (24, 28, and 30 degrees C). Five females from each cohort were taken at 33 degree-day (DD) intervals from 0 to 231 DD (using 17 degrees C as the threshold temperature). Quantitative changes over time of cuticular hydrocarbons associated with gas chromatographic peaks 1 and 5 were identified as having promise for age grading. The relative abundance of peak 1 (pentacosane) decreased linearly from 0 to 132 DD, whereas peak 5 (nonacosane) increased linearly over the same period. Suboptimal larval conditions (crowded and starved), which resulted in physiological stress (decreased size), had negligible effect on the relative abundance of pentacosane and nonacosane. Additionally, the rate of change in the relative abundance of pentacosane and nonacosane were the same for both a recently colonized Chachoengsao (Thailand) strain of Ae. aegypti compared with the long-colonized Rockefeller (Caribbean) strain over a 0-99 DD interval. Two linear regression models, one based on the relative abundance of pentacosane and the other on the logit transformation of these values, were developed for aging female Ae. aegypti. A blind study using laboratory-reared mosquitoes and a mark-release-recapture experiment using field mosquitoes validated these age-grading models and produced promising results for aging females up to 132 DD (19, 12, and 10 calendar days at 24, 28 and 30 degrees C, respectively). Therefore the regression models, based on the relative abundance of these 2 cuticular hydrocarbons, appeared to be a useful approach for age-grading Ae. aegypti up to at least 12 d of age regardless of environmental conditions (temperature and stress) and population history (origin and colonization time).
采用带有火焰离子化检测的气相色谱法，来测定埃及伊蚊雌蚊表皮碳氢化合物随时间的定量变化。对未受胁迫的洛克菲勒品系埃及伊蚊群体，在3个恒定温度（24、28和30摄氏度）下进行饲养和培育。从每个群体中每隔33度日（DD）选取5只雌蚊，范围从0至231度日（以17摄氏度作为阈值温度）。与气相色谱峰1和峰5相关的表皮碳氢化合物随时间的定量变化被确定具有用于年龄分级的潜力。峰1（二十五烷）的相对丰度在0至132度日期间呈线性下降，而峰5（二十九烷）在同一时期呈线性增加。次优幼虫条件（拥挤和饥饿）导致生理应激（体型减小），但对二十五烷和二十九烷的相对丰度影响可忽略不计。此外，在0至99度日的区间内，新引入的泰国差春骚品系埃及伊蚊与长期引入的加勒比洛克菲勒品系相比，二十五烷和二十九烷相对丰度的变化率相同。针对埃及伊蚊雌蚊的年龄判定，建立了两个线性回归模型，一个基于二十五烷的相对丰度，另一个基于这些值的对数变换。一项使用实验室饲养蚊子的盲法研究以及一项使用野外蚊子的标记释放再捕获实验验证了这些年龄分级模型，并在高达132度日（分别在24、28和30摄氏度下为19、12和10个日历日）的雌蚊年龄判定中产生了有前景的结果。因此，基于这两种表皮碳氢化合物相对丰度的回归模型，似乎是一种用于埃及伊蚊年龄分级的有用方法，至少适用于12日龄以内的蚊子，且不受环境条件（温度和应激）以及种群历史（起源和引入时间）的影响。
