Effects of ivermectin on survival, fecundity, and egg fertility in Culicoides variipennis (Diptera:Ceratopogonidae).
Colonized female Culicoides variipennis were fed through an artificial membrane on sheep blood meals containing 0-1.0 microgram/ml of ivermectin. Significant mortalities were present at 48 h postfeeding, with probit analysis yielding an LC50 of 0.35 microgram/ml and a slope of 4.12. All dosages caused significant decreases (P < 0.01) in egg production and sporadic decreases in egg hatch, with no eggs produced at 1.0 microgram/ml. There was a negative linear correlation (r2 = 0.91) between dose rate and number of eggs produced per living female. An inoculation of ivermectin at the recommended dosage of 200 micrograms/kg of body weight would not produce the serum concentration that could be expected to have noticeable effects on bloodfeeding C. variipennis.
Arthropod-Borne Animal Diseases Research Laboratory, USDA-ARS, Laramie, WY 82071-3965.
F R
FR
Holbrook
B A
BA
Mullens
D000818:Animals; D002519:Ceratopogonidae / Q000187:drug effects*; D005260:Female; D005298:Fertility / Q000187:drug effects; D007559:Ivermectin / Q000494:pharmacology*; D010063:Ovum / Q000187:drug effects
D007559:Ivermectin