Density and distribution of Dirofilaria immitis (Nematoda: Filarioidea) third-stage larvae in Aedes sollicitans and Aedes taeniorhynchus (Diptera: Culicidae).
Numbers and the distribution of third-stage larvae (L3) were investigated in Aedes sollicitans (Walker) and Aedes taeniorhynchus (Wiedemann) female mosquitoes fed Dirofilaria immitis (Leidy) infectious-blood with densities of microfilariae (mf) ranging from approximately 7,100-43,400 mf/ml. At each microfilarial density, a maximum of 63-66 infective larvae were recovered from an Ae. sollicitans alive on day 15 after infection. In comparison with Ae. taeniorhynchus, Ae. sollicitans averaged greater numbers of L3 and from 1.4 to 2.4 times more L3 in the head and labium per infected female. The trend was for greater numbers of L3 to be found in the labium than in the head of Ae. sollicitans, but there were no significant differences between numbers of L3 recovered from these sites in differentially infected females. However, numbers of L3 recovered from the head versus the labium of differentially infected Ae. taeniorhynchus varied significantly with the infectious blood microfilarial density. At the two lowest and highest microfilarial densities, greater numbers of L3 were recovered from the head and labium, respectively. Variations among species in the female body size, blood meal size, and retention of L3 may be factors responsible for differences observed between the total numbers and percentage distribution of D. immitis L3 recovered from the simultaneous blood-fed Ae. sollicitans and Ae. taeniorhynchus.
Parker
B M
BM
Department of Entomology, North Carolina State University, Raleigh 27695-7613, USA.
D000330:Aedes / Q000469:parasitology*; D000818:Animals; D004183:Dirofilaria immitis; D004184:Dirofilariasis / Q000635:transmission; D004283:Dog Diseases / Q000635:transmission; D004285:Dogs; D005260:Female; D007303:Insect Vectors / Q000469:parasitology*; D007814:Larva / Q000469:parasitology; D013045:Species Specificity