V. Rada et al., MICROFLORA IN THE HONEYBEE DIGESTIVE-TRACT - COUNTS, CHARACTERISTICS AND SENSITIVITY TO VETERINARY DRUGS, Apidologie, 28(6), 1997, pp. 357-365
Experiments were carried out to enumerate and characterize the microor
ganisms in the midgut and rectum of the honeybee. Counts of aerobic mi
croorganisms were distinctly lower than counts of anaerobes (10(4)-10(
5) viable cells per gram of intestinal contents versus 10(8)-10(9) per
gram). Total numbers of anaerobic microorganisms were almost identica
l with counts of anaerobic Gram-positive acidoresistant rods. These ba
cteria represent the principal groups of microorganisms in the bee dig
estive tract. Anaerobic and aerobic microorganisms, lactobacilli, coli
forms, staphylococci, Bacillus sp, and yeasts were found in all bees.
Only one out of 31 isolates (Bifidobacterium asteroides) was identifie
d at the species level. Fluvalinate, fumagillin and nystatin significa
ntly increased mortality of bees. Treated bees kept in cages contained
more yeasts than control bees in the beehive. The veterinary drugs te
sted significantly increased counts of yeasts in comparison with the c
ontrol.