CEFE, Univ Montpellier, CNRS, EPHE, IRD, Univ Paul Valéry Montpellier 3, Montpellier, France.
BTS CIRA, Saint-Genis-Laval, France.
Pest Manag Sci. 2022 Oct;78(10):4151-4165. doi: 10.1002/ps.7033. Epub 2022 Jun 28.
A thorough knowledge of the population dynamics of pests and of the main factors affecting population growth is an important prerequisite for the development of effective control strategies. Failures of various treatments aimed at regulating populations of Dermanyssus gallinae are regularly reported in poultry farms and pullulations occur very quickly after first detection. To finely characterize population dynamics of D. gallinae, and to identify the factors modulating population growth, we conducted two successive multi-generation experiments using closed mesocosms equipped with or without automatic counters and housing a host full- or part-time (three nights per week).
Population growth was very rapid and the adult to juvenile ratio very different from the prediction by a mathematical model. A male-biased sex ratio was observed in some mesocosms from 21 days and in most mesocosms from 35 days of population growth originating from an inoculum of adult females. A dramatic slowdown in growth was measured in mesocosms equipped with trackers, where the mites' path to the host was constrained. The slowdown in population growth induced by the intermittent presence of the host compared to its full-time presence was much less marked.
These findings suggest avenues of research for new management methods. They question the relevance of a critical threshold based on traditional trap monitoring to manage D. gallinae. Our results highlight a unique characteristic of D. gallinae that makes it a recalcitrant case to threshold-based practices recommended for integrated pest management (IPM) against other arthropod pests. The dramatic effect of a physical constraint for the mite to access the host (unnatural constrained path) confirms an observation made in 1917 and is a reason to design perches that are less conducive to parasite traffic. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
深入了解害虫的种群动态以及影响种群增长的主要因素是制定有效控制策略的重要前提。在养鸡场，各种旨在调节鸡皮刺螨种群的处理方法经常失败，而且在首次发现后，种群数量会迅速增加。为了精细刻画鸡皮刺螨的种群动态，并确定调节种群增长的因素，我们使用配备或不配备自动计数器的封闭中观系统进行了两次连续的多代实验，这些系统容纳了宿主（全周或每周三天）。
种群增长非常迅速，雌雄比例与数学模型的预测非常不同。在一些中观系统中，从种群增长的第 21 天开始，在大多数中观系统中，从第 35 天开始，观察到雄性偏斜的性别比，这些中观系统来自于接种雌性成虫。在配备追踪器的中观系统中，测量到了种群增长的急剧放缓，追踪器限制了螨虫到宿主的路径。与宿主全周存在相比，宿主间歇性存在导致的种群增长放缓要小得多。
这些发现为新的管理方法提供了研究途径。它们质疑了基于传统诱捕监测来管理鸡皮刺螨的临界阈值的相关性。我们的研究结果突出了鸡皮刺螨的一个独特特征，使其成为基于阈值的做法的一个顽固案例，这些做法是综合虫害管理（IPM）推荐的针对其他节肢动物害虫的做法。螨虫接触宿主的物理限制（非自然受限路径）的巨大影响证实了 1917 年的一项观察结果，这也是设计不利于寄生虫活动的栖息场所的原因。©2022 作者。害虫管理科学由 John Wiley & Sons Ltd 代表化学工业协会出版。
