The effects of protein nutrition on honey bee health and survival

This study evaluated malnutrition as a potential cause of deterioration in honey bee health and contributor to the current rapid decline in North American honey bee populations termed Colony Collapse Disorder (CCD). Worker health was assessed through measurement of longevity, protein content, and intestinal stem cell proliferation in hives maintained under nutritional stress, control, and prosperity conditions. Intestinal stem cell proliferation showed a significant increase with nutritional stress and decrease with nutritional prosperity. In contrast, total soluble protein content of individuals and adult worker lifespan were not systematically affected by the experimental manipulations of protein diet quality. Colony brood production seemed most responsive to the manipulations, suggesting that hive demographic plasticity rather than individual plasticity is important for honey bee acclimation to different food availability. Our results led us to conclude that CCD does not directly result from nutritional stress, such as indigestible pollen. However, intestinal stem cell proliferation was sensitive to diet quality, suggesting possible interaction effects of diet and diseases on honey bee health that may act through the digestive system.