Effects of Low Doses of Ivermectin and Fenthion on Egg Laying by Lucilia sericata (Meigen) (Diptera: Calliphoridae)

  • J. W. McGarry
Research Article


Gravid Lucilia treated topically with ivermectin (0.05 μg/g, which represented approx. 4% of the 48 hr LD50) laid fewer viable egg batches (less than 50% of controls) and more sterile ones, when compared to untreated (P = 0.019) and acetone-treated flies (P = 0.028). This effect was also seen when mature third instar larvae were dosed with 7.6 μg ivermectin/g (P = 0.0075 and 0.016 respectively); number of viable egg batches produced were only 25% of the number laid by the progeny of untreated larvae.

Dosage with fenthion stimulated an increase in the number of viable egg batches laid when incorporated in the original larval feeding medium at 0.2 μg/g liver; fewer viable egg batches were laid by the flies which developed from mature larvae treated with 7.6 μg fenthion/g. Acetone solvent alone had a mild stimulatory effect on topically dosed flies.

Key Words

Fenthion ivermectin Lucilia sericata sublethal effects oviposition 

Mots Cléfs

Fenthion ivermectin Lucilia sericata effets sub-lethaux oviposition 


Le nombre d’oeufs viables pondus par les femelles de Lucilia traitées de façon topique à l’ivermectin (0,05 μg/g, ce qui représente environ 4% de la LD50 par 48 heures), était réduit de 50% par rapport aux femelles de contrôle, avec augmentation du nombre d’oeufs stériles en comparaison avec la ponte des mouches non traitées (P = 0,019) ou traitées à l’acetone (P = 0,028). Cet effet était également observé lorsque des larves de troisième instar étaient traitées avec 7,6 μg d’ivermectin/μg (P =0,0075 et P= 0,016, respectivement); le nombre d’oeufs viables obtenus n’etait que 25% du nombre d’oeufs produits par la progénie des larves non traitées.

Le traitement par le fenthion incorporé au milieu original de nutrition larvaire (0,2 μg/g de foie) a produit une augmentation du nombre d’oeufs viables; un nombre plus faible d’oeufs viable était produit par les mouches ayont émergé de larves matures traitées avec 7,6 μg de fenthion/g. L’acetone suele avait un effet stimulant sur les mouches traitées de façon topique


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Copyright information

© ICIPE 1988

Authors and Affiliations

  • J. W. McGarry
    • 1
  1. 1.Department of Veterinary ParasitologyLiverpool School of Tropical MedicineLiverpoolUK

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