"24. Rhoades, P.R., & J.A. Skinner - EFFECTS OF TREATMENT WITH THYMOL, FUMAGILLIN, HONEY-B-HEALTHY, AND NOZEVIT ON CAGED HONEY BEES INFECTED WITH NOSEMA APIS AND N. CERANAE
Prospective treatments for Nosema disease were evaluated by examining both mortality and spore production in caged honey bees infected with either Nosema apis or N. ceranae. Treatments used were thymol, fumagillin, Honey-B-Healthy, and Nozevit. Bees used in the study were shaken from frames of uncapped brood taken from hives visibly free of Nosema infection. These bees were chilled with ice water, placed in cages (180 bees/cage) and immediately infected with either N. apis or N. ceranae through gravity feeders at a rate of 40,000 spores/bee. Treatment began 3 days after inoculation. Dead bees were removed and counted every subsequent day. Twenty-three days after inoculation, 10-15 bees were removed, abdomens were crushed individually in water, and spores were counted using a hemocytometer.
Although treatment greatly affected mortality, no difference was noted with respect to the species of Nosema. Bees treated with thymol and Honey-B-Healthy were found to have rates of mortality similar to uninfected bees. Bees treated with Nozevit had rates of mortality similar to untreated bees. Fumagillin improved mortality, but not to levels of uninfected bees (Table).
Honey-B-Healthy had no effect on spore production; therefore, the reduction in mortality displayed under treatment must be attributed to positive effects on the bee itself rather than to an antagonistic effect on the pathogen. Fumagillin was the only compound to significantly and consistently reduce spore production. The failure of fumagillin to reduce mortality congruently is unexplained. Thymol and Nozevit had some effect on spore production but it was unclear how significant this effect was.
Table. Spore production and mortality of caged bees that received different treatments being investigated for potential control of Nosema. 1. Bees infected with N. ceranae did not have significantly different mortality than those infected with N. apis; results were pooled for the two species. 2. Mean ± standard erro
OK...This is odd...HBH feed bees had an over all..INCREASED level of spores than infected non treated bees. *however, it is within the margin of error so...* yet they live longer than fumagillin feed bees?
1. - Regarding HBH, what dose was used? Was the recomended dose fed? How much was fed?
2. -In field work, it would be important to know the rate of gut elimination by bees on a daily basis, nurse bees vs foragers. Was there fecal elimination by the nurse bees in the cages?
Being caged the bees were not able to have cleansing flights to eliminate fecal matter, therefore not allowing elimination of accumulated nosema spores.