Browsing by Subject "hygienic behavior"
Now showing 1 - 7 of 7
Results Per Page
Sort Options
Item Behavioral defenses of honey bees against Varroa jacobsoni Oud.(1999) Boecking, Otto; Spivak, MarlaTwo behaviors of honey bees, hygienic behavior and grooming, are mechanisms of defense against brood diseases and parasitic mites. Studies have shown that Apis mellifera colonies remove worker brood infested with Varroa jacobsoni mites from the nest (hygienic behavior), and groom the mites off other adult bees, but to a limited extent compared to the original host of V. jacobsoni, A. cerana. Research is reviewed on hygienic and grooming behaviors with respect to their potential as mechanisms of resistance to V. jacobsoni. Studies related to hygienic behavior include the removal of experimentally infested and naturally infested brood, measurements of heritability, the uncapping and recapping of cells containing infested pupae, and the detection of infested brood. Studies on grooming include the process by which a groomer detects and damages a mite found on itself or on another adult bee, how the behavior is quantified, and problems with these methods of quantification. Finally, unresolved questions concerning grooming and the effects of hygienic and non-hygienic behaviors on limiting the population growth of V. jacobsoni are discussed.Item Field trial of honey bee colonies bred for mechanisms of resistance against Varroa destructor(2007) Ibrahim, Abdullah; Reuter, Gary S.; Spivak, MarlaWe compared colonies selectively bred for both hygienic behavior and Suppression of Mite Reproduction (HYG/SMR) with colonies bred solely for hygienic behavior (HYG) and unselected control colonies. Colonies were evaluated for strength, brood viability, removal of freeze-killed brood, honey production, mite loads on adult bees and within worker brood, and mite reproductive success on worker brood for two years in two locations. By autumn in both years, the HYG/SMR colonies had significantly fewer mites on adult bees and in worker brood compared to the control colonies, and the HYG colonies had intermediate mite populations. Contrary to expectation, there were no differences among the lines in mite reproductive success. Further studies are required to determine if the genes and neural mechanisms that regulate the SMR trait are the same or different from those regulating hygienic behavior.Item Honey bee hygienic behavior and defense against Varroa jacobsoni(Springer, 1996) Spivak, MarlaHygienic and non-hygienic colonies from ’Starline’ stock of Apis mellifera were tested for their ability to remove pupae infested with Varroa mites. The hygienic and non-hygienic lines were selected and bred on the basis of their removal response to freeze-killed brood. A Jenter Box® was used to test whether they would remove experimentally infested pupae following methods of Boecking and Drescher (1992). In 1994, the hygienic colonies removed significantly more pupae infested with one mite per cell than the non-hygienic colonies. In 1995, there was no significant difference between the hygienic and non-hygienic colonies when one or two mites were introduced per pupa due to variation in response among hygienic colonies. There was no significant difference between the rate of removal of infested pupae from the Jenter Box and from natural wax comb by the hygienic colonies. The number of mites damaged by grooming ranged from 6.0 to 42.3% among all colonies. The reproductive success of the mites not removed from the cells by the bees was low in both hygienic and non-hygienic colonies.Item A multifactorial study of the resistance of honeybees Apis mellifera to the mite Varroa destructor over one year in Mexico(2005) Mondragon, Luis; Spivak, Marla; Vandame, RemyA one year study was conducted to evaluate the population growth of three kinds of honey bee colonies and Varroa destructor mites in Mexico, and to estimate the relative contributions of three resistance mechanisms of the bees: hygienic behavior, grooming behavior, and reproductive ability of the parasite. Very significant changes over the year were observed in the number of mated female offspring produced per mother mite (Wr), mite fertility and mutilation of V. destructor. These changes were correlated to the total number of mites per colony. A factorial analysis showed that two mechanisms explained the variation in the amount of mites per colony: Wr (r2 = 0.73) and proportion of mutilated mites (r2 = 0.51). A multi-factorial model including these two mechanisms was significant (r2 = 0.97). The mite fecundity and the hygienic behavior could not explain the population changes of the mite, and the different kinds of bees showed no differences in the expression of the resistance mechanisms.Item Performance of hygienic honey bee colonies in a commercial apiary(1998) Spivak, Marla; Reuter, Gary S.Colonies with naturally mated queens from a hygienic line of Italian honey bees (Apis mellifera ligustica) were compared to colonies from a commercial line of Italian bees not selected for hygienic behavior. The following characteristics were compared: rate of removal of freeze-killed brood; amount of chalkbrood; incidence of American foulbrood; honey production; and the number of mites, Varroa jacobsoni, on adult bees. The hygienic colonies removed significantly more freeze-killed brood than the commercial colonies, had significantly less chalkbrood, had no American foulbrood, and produced significantly more honey than the commercial colonies. Estimates of the number of Varroa mites on adult bees indicated that the hygienic colonies had fewer mites than the commercial colonies in three of four apiaries. In previous studies on the relation between hygienic behavior and resistance to diseases and mites, the test colonies contained instrumentally inseminated queens. This is the first study to evaluate hygienic stock in large field colonies with naturally mated queens.Item The relationship between hygienic behavior and suppression of mite reproduction as honey bee (Apis mellifera) mechanisms of resistance to Varroa destructor(2006) Ibrahim, Abdullah; Spivak, MarlaWe compared the mechanisms of resistance to Varroa destructor displayed by bees bred for Suppression of Mite Reproduction (SMR) and hygienic behavior (HYG). Mites from SMR and HYG source colonies were introduced into recently sealed SMR and HYG worker brood, and the infested pupae were placed either into recipient colonies or into an incubator. SMR colonies removed significantly more miteinfested pupae than the HYG colonies. The reproductive success (fertility and number of viable female offspring) of mites from both sources on pupae not removed by bees was significantly lower in SMR colonies. Within the incubator, the reproductive success of mites was also lower on SMR worker pupae, and lowest when mites from SMR colonies were introduced on SMR brood. Our findings indicated that bees bred for SMR express hygienic behavior; adult bees selectively remove pupae infested with mites. In addition, there is an effect of SMR pupae that reduces mite reproductive success that requires further investigation.Item Resistance to American foulbrood disease by honey bee colonies Apis mellifera bred for hygienic behavior(2001) Spivak, Marla; Reuter, Gary S.Honey bee colonies, selected for hygienic behavior on the basis of a freeze-killed brood assay, demonstrated resistance to American foulbrood disease. Over two summers in 1998 and 1999, 18 hygienic and 18 non-hygienic colonies containing instrumentally inseminated queens were challenged with comb sections containing spores of the bacterium Paenibacillus larvae subsp. larvae that causes the disease. The strain of bacterium was demonstrated to be resistant to oxytetracycline antibiotic. Seven (39%) hygienic colonies developed clinical symptoms of the disease but five of these recovered (had no visible symptoms) leaving two colonies (11%) with clinical symptoms. In contrast, 100% of the non-hygienic colonies that were challenged developed clinical symptoms, and only one recovered. All non-hygienic colonies had symptoms of naturally occurring chalkbrood disease (Ascosphaera apis) throughout both summers. In contrast 33% of the hygienic colonies developed clinical symptoms of chalkbrood after they were challenged with American foulbrood, but all recovered. The diseased non-hygienic colonies produced significantly less honey than the hygienic colonies.