Seasonal Variation in the Infection of Honeybee Colonies with Nosema Apis Zander

Does fumagillin control the recently detected invasive parasite Nosema ceranae in western honey bees (Apis mellifera)?

“…Differences between treated and untreated colonies disappeared approximately 1 year after treatment, suggesting that infected colonies naturally recover during the summer (Pickard and El-Shemy, 1989), that fumagillin loses its efficacy (Furgala, 1962), or that fumagillin becomes depleted from colony honey stores.…”

“…In Canada, Fumagilin-B Ò (Medivet Pharmaceuticals Ltd.) is the only commercially registered product containing fumagillin available to beekeepers for Nosema treatment. Chemotherapy typically occurs during fall syrup-feeding of hives (Gochnauer and Furgala, 1969), before peak infection during winter and early spring (Pickard and El-Shemy, 1989). Fall and spring chemotherapy is often recommended for severe infections, but this may not reduce N. apis below damaging levels (Wyborn and McCutcheon, 1987).…”

Effects at Nearctic north-temperate latitudes of indoor versus outdoor overwintering on the microsporidium Nosema ceranae and western honey bees (Apis mellifera)

“…Both species can be controlled using the antibiotic Fumagilin-B Ò ; unfortunately, treatment never completely eliminates infection (Higes et al, 2008;Williams et al, 2008b). Because infection levels of N. apis typically increase rapidly in spring as brood-rearing starts but while cleansing flights are infrequent (Pickard and El-Shemy, 1989), indoorwintering may reduce Nosema levels in spring by allowing beekeepers to move colonies outdoors when cleansing flights are possible. Here, we investigated effects of overwintering environment (indoor versus outdoor) on spring N. ceranae intensity and on winter and spring colony mortality.…”

Internal hive temperature as a means of monitoring honey bee colony health in a migratory beekeeping operation before and during winter

“…Overwintering loss rate is an important measure because a healthy colony is worth a premium in commercial pollination; it may be split into two or more colonies to increase holdings; and it is more likely to produce large amounts of honey the following year (Harris 2009). Conversely, many diseases and deficiencies can manifest or amplify during the overwintering period including Varroa , various viruses, trypanosomes, Nosema disease, and non-Nosema dysentery (Runckel et al 2011;Dainat et al 2012;Pickard and El-Shemy, 1989;Schwarz et al 2015;Van Dooremalen et al 2012). Pesticide exposure in the fall can compromise immune defenses, increase Nosema and Varroa levels, and decrease colony growth during and after overwintering (Pettis et al 2013;Dively et al 2015;Meikle et al 2016a).…”