In Italy a nation-wide monitoring network was established in 2009 in response to significant honey bee colony mortality reported during 2008. The network comprised of approximately 100 apiaries located across Italy. Colonies were sampled four times per year, in order to assess the health status and to collect samples for pathogen, chemical and pollen analyses. The prevalence of Nosema ceranae ranged, on average, from 47–69% in 2009 and from 30–60% in 2010, with strong seasonal variation. Virus prevalence was higher in 2010 than in 2009. The most widespread viruses were BQCV, DWV and SBV. The most frequent pesticides in all hive contents were organophosphates and pyrethroids such as coumaphos and tau-fluvalinate. Beeswax was the most frequently contaminated hive product, with 40% of samples positive and 13% having multiple residues, while 27% of bee-bread and 12% of honey bee samples were contaminated. Colony losses in 2009/10 were on average 19%, with no major differences between regions of Italy. In 2009, the presence of DWV in autumn was positively correlated with colony losses. Similarly, hive mortality was higher in BQCV infected colonies in the first and second visits of the year. In 2010, colony losses were significantly related to the presence of pesticides in honey bees during the second sampling period. Honey bee exposure to poisons in spring could have a negative impact at the colony level, contributing to increase colony mortality during the beekeeping season. In both 2009 and 2010, colony mortality rates were positively related to the percentage of agricultural land surrounding apiaries, supporting the importance of land use for honey bee health.

No abstract

No abstract

The aim of this study was to evaluate the effect of thymol and resveratrol administered in two different formulation modes (candy and syrup) on the development of Nosema ceranae and on the longevity of honey bees. Emerging bees from a nosema-free apiary were individually infected with 1 μL of sucrose syrup containing 18000 spores of N. ceranae, placed in cages, and kept in an incubator at 33 • C and 65% RH. The experimental groups were fed candy or syrup prepared with thymol (100 ppm) or resveratrol (10 ppm). Infection levels were monitored over a 25 day period by removal and dissection of two live bees per cage. On day 25, post-infection bees fed with thymol syrup had significantly lower levels of infection (60 ± 9 million spores/bee) compared to control bees (138 ± 7 million spores/bee). Bees fed with thymol or resveratrol syrup lived significantly longer (23 and 25 days, respectively) than bees fed with control syrup (20 days). Thymol treated syrup appears to be promising in the control of nosema infection. Nosema / microsporidian / honey bee / thymol / resveratrol

-The potential of some natural compounds (thymol, vetiver essential oil, lysozyme, resveratrol) for the control of nosema infection in honeybees was evaluated. A first trial aimed at screening substances, in candy preparations, on the basis of their toxicity to honeybees and bees' dietary preferences. None of the tested substances showed an increased bee mortality or decreased bee preference, and were therefore considered suitable for further testing. In the second trial the effects of the natural compounds on nosema diseased honeybees were evaluated: bees were individually dosed with nosema spores and fed candies prepared with the screened substances. The results showed that bees fed with thymol and resveratrol candies had significantly lower infection rates, and bees supplied with resveratrol prepared candy also lived significantly longer. We suggest that thymol and resveratrol could be useful in alternative strategies for the control of nosema disease.Nosema / microsporidian / honeybee / thymol / resveratrol

SummaryAdaptation of honey bees to their environment is expressed by the annual development pattern of the colony, the balance with food sources and the host -parasite balance, all of which interact among each other with changes in the environment. In the present study, we analyse the development patterns over a period of two years in colonies belonging to 16 different genotypes and placed in areas grouped within six environmental clusters across Europe. The colonies were maintained with no chemical treatment against varroa mites. The aim of the study was to investigate the presence of genotype -environment interactions and their effects on colony development, which we use in this study as a measure of their vitality. We found that colonies placed in Southern Europe tend to have lower adult bee populations compared to colonies placed in colder conditions, while the brood population tends to be smaller in the North, thus reflecting the shorter longevity of bees in warmer climates and the shorter brood rearing period in the North. We found that both genotype and environment significantly affect colony development, and that specific adaptations exist, especially in terms of adult bee population and overwintering ability. 234Hatjina and Costa et al.

The authors' names are listed in alphabetical order with the exception of the corresponding author. All authors' contributions are equal. SummaryThe term "quality" in relation to queens and drones refers to certain quantitative physical and / or behavioural characters. It is generally believed that a high quality queen should have the following physical characteristics: high live weight; high number of ovarioles; large size of spermatheca; high number of spermatozoa in spermatheca; and be free from diseases and pests. It is, however, also known that the performance of a honey bee colony is the result of its queen's function as well as of that of the drones that mated with her. These two approaches are often considered together and give a general picture of the queen production technique and selection. Here we describe the most common and well known anatomical, physiological, behavioural and performance characters related to the queens, as measured in different European countries: the live weight of the virgin queen (Bulgaria); the live weight of the laying queen (Bulgaria, Italy); the diameter and volume of spermatheca (Bulgaria, Greece, Slovenia); the number of ovarioles (Greece, Italy, Slovenia); the weight of ovaries (Slovenia); the number of spermatozoa in spermatheca (Italy, Poland, Slovenia); the brood pattern (Bulgaria, Greece); the egg laying ability / fecundity (Bulgaria); the brood production (Croatia, Serbia); the colony population development (Croatia, Serbia, Slovakia); the honey production (Croatia, Denmark, Serbia, Slovakia); the hygienic behaviour (Croatia, Denmark, Serbia, Slovakia); the defence behaviour (Croatia); the calmness / sitting on the comb (Croatia, Denmark); and swarming (Croatia, Denmark). The data presented fit well with the findings of the same characters in the literature, and in general they support the argument for the term "quality characters". Especially for the weight of the queen, the number of ovarioles, the volume of the spermatheca and the number of spermatozoa, data per country proved its own accuracy by repetition through the years. We also report that when instrumentally inseminated queens are kept under mass production conditions (in 338 Hatjina et al.

The genetic variability of Apis mellifera ligustica was screened throughout the Italian peninsula and Sardinia with eight polymorphic microsatellite loci. Samples of Apis mellifera mellifera, Apis mellifera carnica and from the Buckfast breeding line were genotyped for comparison. Low Fis and Fst values suggest the absence of genetic structure within and among A. m. ligustica populations, although the high number of alleles detected and heterozygosity. Phylogenetic and individual analyses confirmed that A. m. ligustica has come to resemble one large population, probably as a result of intensive beekeeping practices such as migratory beekeeping and large-scale commercial queen trading. Since the introgression of foreign alleles into both endemic natural and commercial A. m. ligustica populations, can be detected and monitored by microsatellite analysis, the results provide a reference data set for future local biodiversity conservation and other controlled breeding programs.