The use of artificial diets to determine some of the effects of Nocardia rhodnii on the development of Rhodnius prolixus

Abstract

Rhodnius prolixus cannot develop normally on rabbit blood in the absence of its normal symbiont Nocardia rhodnii. Most aposymbiotic larvae failed to ecdyse from the fourth to the fifth instar. Aposymbiotic second to fourth instar larvae fed on rabbits were significantly heavier than were normal larvae of the same instar, and took longer to ecdyse at every instar. When rabbit blood was supplemented with high concentrations of folic acid, nicotinic acid, pantothenic acid, pyridoxine, riboflavin, and thiamine the development of aposymbiotic fourth and fifth instar larvae was significantly improved, but was still inferior to that of normal larvae fed unsupplemented blood. It was concluded that under normal conditions N. rhodnii supplies its host with folic acid, pantothenic acid, pyridoxine, and thiamine, and may also provide nicotinic acid and riboflavin. The artificial feeding technique used was very successful. It allowed freedom of diet manipulation, and diet acceptance by the insects was good.