Characteristics of Honey Bee (Apis Mellifera Carnica, Pollman 1879) Queens Reared in Slovenian Commercial Breeding Stations

Abstract

A b s t r a c t In this three-year-trial study, we examined the quality of mated queens based on morphological and physiology traits. At each location, sister queen bees were reared each year from one Apis mellifera carnica breeder queen. Queens were also reared and mated in different locations. Altogether, we sampled and analysed 324 queens from 27 apiaries in 2006, 288 queens from 24 apiaries in 2008, and 276 queens from 23 apiaries in 2010. Nine queens from each apiary were sampled and dissected for morphological analyses and Nosema ceranae (N. ceranae) spores, if present, were quantified. Three queens from each apiary were prepared and tested for four viruses: acute bee paralysis virus (ABPV), black queen cell virus (BQCV), deformed wing virus (DWV), and sacbrood virus (SBV). The highest average queen weight of 209.49 ± 9.82 mg was detected in 2008. The highest average ovary weight of 78.67 ± 11.86 mg was detected in 2010, and the highest number of ovarioles was 161.59 ± 8.70 in 2006. The average number of spermatozoa in queens ranged from 3.30 x 10 6 in 2006 to 5.23 x 10 6 in 2010. Nosema ceranae spores were found in queens sampled in 2008 and 2010. Viruses were discovered sporadically during the queen testing periods from 2006 -2010. This study importantly demonstrates that queens from rearing stations require regular evaluation for morphological and physiological changes as well as for infection from harmful pathogens. These results could also be used in establishing relevant commercial standards for rearing quality queens. Keywords: bee virus, Nosema spp., ovariole, ovary, queen rearing, spermatheca.Agricultural institute of Slovenia, Hacquetova ulica 17, 1000 Ljubljana, Slovenia INTRODUCTIONThe Carniolan honeybee bee, Apis mellifera carnica Pollman 1879, is an indigenous subspecies and has been preserved in all the five geographic areas of Slovenia: Prekmurje, Štajerska, Gorenjska, Dolenjska, and the Central Region. Queen producers annually test the performance of selected colonies for queen evaluation and for further breeding. The aims of queen breeding in Slovenia are to both preserve native wildtype strains and to maintain desirable honeybee traits. However, various environmental factors can affect the quality of queen bees; for example, the rearing season and weather can alter the queens' development rate (Mahbobi et al., 2012). Therefore, evaluating morphological, behavioural, and reproductive traits of male and female bees in response to the climate within apiaries, is also important when selecting for queens. Morphological traits such as body size and a bee's reproductive performance are often linked and subject to environmental factors (Reiss, 1989). If the bee is a queen, any change in body weight can irrevocably alter her egg laying capacity (Harbo, 1986). Heavier queens have more ovarioles and larger spermathecae that are capable of holding more sperm (Woyke, 1971;Szabo, 1973;Eid et al., 1980). Even large queens may lose reproductive fitness when afflicted with pathogens and parasites. The mi...

Honey Bee Queens and Virus Infections

“…High DWV titer detected from endophalli collected from captured drones from the drone congregation areas or from queens returning from their mating flights support that DWV venereal transmission can occur during natural mating [35,77]. As a result of venereal transmission, young mated queens are infected with more viruses than young unmated queens [35,44,78]. Older mated queens tend to be infected with yet a greater number of viruses, including DWV, SBV, BQCV, and AKI complex (ABPV, KBV, and IAPV), at higher infection titers [44,56,79].…”

“…Consequently, little is known about how virus infections affect the behavior, physiology, reproduction, and longevity of queens. Numerous viruses (DWV, SBV, CBPV, ABPV, KBV, and IAPV) have been detected from heathy looking queens, demonstrating that infection can occur either by single or multiple viruses in a queen [75,76,78,92]. Viruses infect different parts of the queen's body, including the head, thorax, ovaries, spermatheca, and fat body [56,59,79,93].…”

Putative Drone Copulation Factors Regulating Honey Bee (Apis mellifera) Queen Reproduction and Health: A Review

“…Honey bee queens are typically assessed for their quality based on reproductive longevity, potential amount of viable brood they can produce, the number of the drones with which they have mated, and the genetic diversity of her mates [28]. There are several traits that are associated with queen quality, including overall weight [11,28,29,30,31,32,33], weight of the ovaries [34,35,36], weight of the spermatheca, and the number of viable stored spermatozoa [11,28,29,37,38,39,40]. Queen quality is impacted by the age at which larvae are nutritionally directed into the queen developmental pathway via continued feeding of royal jelly [12,41,42,43].…”

Sperm Quality Assessment in Honey Bee Drones

“…The most frequently used criterion in assessing the reproductive quality of the young queen is to consider a threshold of 3 million sperm stored in the spermatheca to discriminate the quality of insemination [ 78 ]. The proportion of poorly inseminated queens (< 3 million sperm) ranged between 13.6% and 19.0% in the different studies [ 51 , 52 , 84 , 86 , 87 ]. Biotic, abiotic and management practices could affect the insemination quality of the queen [ 84 ].…”