Seasonal Variations in Nutritional Composition of Honeybee Pollen Loads

ABSTRACT: Seasonal nutritional content of honeybee pollen loads collected from five apiaries across the Al-Ahsa oasis, Saudi Arabia, was determined over a period of one year. Botanical composition of the pollen loads was dominated by rapeseed (Brassica napus L.), summer squash (Cucurbita pepo Thunb), date palm (Phoenix dactylifera L.), sunflower (Helianthus annuus L.), and alfalfa (Medicago sativa L.). The highest amounts (g/colony) of pollen loads were collected during spring and winter, and the lowest during autumn, and there were seasonal variations in and among nutrient content. The highest values of fructose, crude protein, lipids, and ash content were recorded from pollen loads collected during spring and winter, and the highest values of glucose and moisture content were recorded from pollen loads collected in autumn; pollen loads collected during summer showed the highest values of total and available carbohydrate, and crude fiber content. The high content of fructose, crude protein, lipids, and ash in pollen loads collected during the spring and winter seasons indicate they represent a valuable food supplement.