Does a parasite infestation change the nutritional value of an insect? Varroa mites on honey bees as a model

Abstract

The impact of parasites on the nutritional value of their hosts may be an important issue that has to be studied in considering insects as future food and feed for humans and animals. The ectoparasiteVarroa mite (Varroa destructor) was chosen as an experimental model: it affects bee colonies and largely endangers the honey production. Honey bee (Apis mellifera) brood is largely used as human food in tropical regions and has a great potential to become a future source of proteins and other nutritional and health components, in particular because beekeeping is based on deep knowledge and well developed technologies in great parts of the world. The impact of infestation ofVarroa on the nutritive qualities of honey bee brood is barely known. We compared the main components of infested and parasite free pupae, harvested from the same colonies. We found thatVarroa mites decreased the mean fresh weight from 124±6.9 to 118±4.1 mg (mean ± standard deviation), elevated the intensity of one protein band (50.2 KDa) among nine and enhanced the superoxide dismutase activity from 9.5±0.3 to 14.6±0.2% but not catalase and peroxidase activity. The parasite did not change the dry weight percentage (19.5±1.9%), total lipid titration (16.9±2.3%), crude protein (57.2±6.1%) and cholesterol levels (6.7±1.3 mg/100 g fresh weight). The fatty acid composition and their proportions were not altered either, among them three very important unsaturated fatty acids (FAs): omega-3, omega-6 and oleic acid/omega-9. Long chained FAs were detected in small quantities, less than 1%. The total antioxidant activity remained the same as of not-infested pupae. In conclusion, the impact ofVarroa mites on the nutritional value of honey bee pupae could be considered as minor.