The development of Parafilaria bovicola in Musca xanthomelas and Musca lusoria

Abstract

Artificially infected adult flies were used in this study. In both Musca species, P. bovicola developed in the fat-body cells, mainly of the abdomen. Escape from the midgut and penetration of the fatbody cell was possibly achieved by use of the cephalic hook of the microfilaria. At 27 °C, development to the 3rd larval stage took 9 days, but maximum length was only reached after 11 days. Sharp increases in larval length took place on Days 6-7 and on Day 9. These sudden increases possibly indicate moults to the 2nd and 3rd larval stages respectively. During larval development the fat-body cell increased markedly in size to form a thin-walled capsule around the larva. On reaching the 3rd stage, larvae escaped from the capsules and migrated to the head cavity and proboscis.