, Mention of a proprietary product does not constitute endorsement by the USDA-ARS SUMMARY Four experiments were conducted to examine factors that influence the expression of hygienic and non-hygienic behaviour in honey bees, Apis mel/itera, and to examine the correlation between this behaviour and resistance to chalkbrood, Ascosphaera apis. Colonies were headed by instrumentally inseminated qu...

Introduction American Foulbrood (AFB) is one of the most threatening epidemic brood diseases in honey bee colonies. This disease is caused by the pathogen Paenibacillus larvae larvae. According to the common animal health law in Germany the outbreak of AFB has to be reported to veterinarian service. The veterinarian has to decide about eradication of bee colonies, cleaning and disinfection as w...

Reproductive division of labour is based on biased expression complementary parental behaviours, brood production (egg-laying) by queens and care (in particular, brood-provisioning) workers. In many social insect species, provision when establishing colonies at the beginning a breeding season reproductive begins with emergence foraging (for) mRNA associated intensity behaviour therefore brood-p...

1. Beja & Palma (2008, Journal of Animal Ecology, 77, doi: 10.1111/j.1365-2656.2007.01312.x) attempt to provide a critical analysis of the effectiveness and limitations of a previously published method (Ferrer et al. 2006, Journal of Animal Ecology, 75, 111-117.) to discriminate between Habitat Heterogeneity Hypothesis and the Individual Adjustment Hypothesis using real data from a Bonelli's ea...

Brood parasitic birds impose variable fitness costs upon their hosts by causing the partial or complete loss of the hosts' own brood. Growing evidence from multiple avian host-parasite taxa indicates that exposure of individual hosts to parasitism is not necessarily random and varies with habitat use, nest-site selection, age or other phenotypic attributes. For instance, nonrandom patterns of b...

Oxidative stress, determined by the balance between the production of damaging reactive oxygen species (ROS) and antioxidant defences, is hypothesized to play an important role in shaping the cost of reproduction and life history trade-offs. To test this hypothesis, we manipulated reproductive effort in 94 breeding pairs of tawny owls (Strix aluco) to investigate the sex- and melanism-specific ...

Environmental factors play a key role in the expression of phenotypic traits and life-history decisions, specifically when they act during early development. In birds, brood size is such an important environmental factor affecting development. Experimental manipulation of brood sizes can result in reduced offspring condition, indicating that conditions during development in enlarged broods have...

After more than a century of American Foulbrood (AFB) research, this fatal brood infection is still among the most deleterious bee diseases. Its etiological agent is the Gram-positive, spore-forming bacterium Paenibacillus larvae. Huge progress has been made, especially in the last 20 years, in the understanding of the disease and of the underlying host-pathogen interactions. This review will p...

Prolonged brood care is one of the evolutionary clues for the successful colonization of freshwater habitats by freshwater crayfish (Astacida). By means of macrophotography, light microscopy, and scanning electron microscopy we investigated all phases of brood care in freshwater crayfish, with particular emphasis on the morphological structures involved. We selected the recently discovered part...

Many songbird species have experienced significant population declines, partly because of brood parasitism by the Brown-headed Cowbird (Molothrus ater), which is positively associated with increasing landscape forest cover in the midwestern United States. However, cowbirds are also experiencing long-term population declines, which should reduce parasitism pressure and thus increase productivity...