EFFECT OF THE NUMBER OF ATTENDANT WORKER BEES ON THE INITIATION OF EGG-LAYING BY INSTRUMENTALLY INSEMINATED QUEENS KEPT IN SMALL NUCLEI

Altogether 70 queens, 7-8 days old were instrumentally inseminated with 8 mm3 of semen. They were introduced in groups per 10 to 150, 350 and 750 workers in 1- and 4-comb mating boxes, and to 10 larger nuclei with 9500 workers on 5 normal combs. The nuclei were checked daily, and the initiation of egg laying, as well as the temperatures inside the bee cluster and outdoors were recorded. Queens attended by 150, 350 and 750 workers started to lay eggs in 1-comb mating boxes 15.1, 13.5 and 11.5 days after insemination, respectively; in 4-comb mating boxes 12.6, 12.1 and 9.9 days after insemination; and in the large nuclei, 6.9 days after insemination. Increase of the number of attendants by 100 workers accelerated initiation of egg laying by 0.59 or 0.46 day in 1-comb or in 4-comb mating boxes, respectively. Logarithmic regression curve y = 26.37 - 2.2 1n x fits well for initiation of egg laying by queens in 1-comb boxes and y = 18.30 - 2.2 1n x for queens in 4-comb boxes. Doubling the number of attendants accelerated initiation of egg laying by 0.8 - 0.9 day. Increase of the number of workers from 150 to 750 raised the temperature in the bee cluster in mating boxes from 2.3-degrees-C to 4.6-degrees-C above the 19.5-degrees-C of the average outdoor temperature. Increase of workers by 100 raised the temperature by 0.26-degrees-C or 0.33-degrees-C in 1- or 4-comb boxes, respectively. Logarithmic regression curve y = 3.3 + 1.2 1n x fits well for the rise of temperature generated by increasing number of workers in 4-comb boxes. Doubling the number of workers raised the temperature by 0.8-degrees-C. Increase of temperature by 1-degrees-C was associated with acceleration of the initiation of egg laying by about 1-2 days.