TIME APPEARANCE OF NON - INFECTIOUS CHILLED BROOD DISEASE AND ITS EFFECT ON HONEYBEE BROOD AND BEE FORAGING ACTIVITY

Abstract

Climate changes especially temperature played a big role in the survival of honeybee. The present study evaluated the effect of chilled brood disease from three axes: relationship with temperature, brood area and foraging activity during the two successive winter seasons of 2019/2020 and 2020/2021. Results recorded negative relation between chilled larvae and inter/outer temperature: -0.8707 and -3.6313 for inter temperature, -0.3462 and 0.6065 for outer temperature in 2019/2020 and 2020/2021, respectively. On the other hand data showed significant decrease in mean area of larvae reared chilled brood diseases in bad wintering which showed 26.50 inch 2 comparing with 36.46 inch 2 in reared in perfect wintering (control) and brood area which reduced from 36.46 to 26.50 inch sq. and from 40.59 to 28.88 inch sq. in winter 2019/2020 and 2020/2021, respectively. Finally, foraging bee activity of bees in the obtained results showed high effect between chilled brood symptoms and foraging rate, which decrease the number of returned workers from10.71 to 6.88 bee/min. and from 13.00 to 8.21 bee/min. in seasons 2019/2020 and 2020/2021, respectively.