Correction: In a previous post, when discussing the Australian research on gut bacteria (https://rirdc.infoservices.com.au/downloads/09-120.pdf), I posted: > "The Aussie paper also indicates that the crop bacteria largely disappear > in the absence of feeding." > An alert reader pointed out off list that I should not have used the word "crop," but rather "gut". I stand corrected. The reader also questioned "i also don't see any reference in the paper to gut bacteria "largely disapearing" in the absence of feeding....unless you are talking about feeding the bees probiotic bacterial cultures, which is entirely different from "feeding" as any reader would understand it." I've reread the paper, and am not sure how to respond. I'll cite the relevant passages below, and let you decide for yourselves. It appears to me that the two strains introduced thrived on continual sugar syrup feeding. The authors did not look for other strains of bacteria during the tests. It is not clear to me whether the colonization of bacteria was due to continual inoculation, or due to the sugar syrup feeding, since the authors didn't test with syrup feeding alone. For the first time (world-wide) probiotic feeding experiments were designed and carried out to determine if fed bacteria could be established in the bee gut. Bacillus and Pseudomonas species were marked with antibiotic resistance and fed to bees in apiaries in sugar solution. It was found that high numbers of bee gut bacteria could be maintained while regular feeding occurred. However there was a marked decline of the introduced bacteria over a period of time as soon as feeding stopped. This occurred more rapidly during summer feeding, compared to winter feeding. The feeding of sugar solution seems to be the only artificial way to improve recovery from Chalkbrood disease currently. The increase in gut microflora with this method again suggests this to be a beneficial method for increasing gut bacterial populations. Therefore feeding of sugar solution can also be recommended in relation to gut microflora maintenance. The Pseudomonas and Bacillus strains tested in these experiments gave similar results. For both Pseudomonas and Bacillus, the number of bees carrying the artificially-fed bacteria reduced in both field trials, which were carried out at different times of the year (winter and summer), once the feeding had stopped. However, this decline was far more rapid in the case of bees fed in summer, presumably because the bees at this time are foraging more, and thus that there is likely to be a higher turnover of bacteria in the bee gut during this period. This suggests that the two test strains did not colonise the bee gut effectively for longer-term survival. However it is encouraging at this stage to know that continuous feeding of bacteria to a bee colony introduces the bacteria in high numbers to a significant population of worker bees. Randy Oliver *********************************************** The BEE-L mailing list is powered by L-Soft's renowned LISTSERV(R) list management software. For more information, go to: http://www.lsoft.com/LISTSERV-powered.html Access BEE-L directly at: http://community.lsoft.com/scripts/wa-LSOFTDONATIONS.exe?A0=BEE-L