The research, led by Canadian researchers, demonstrates how probiotics could potentially stave off a common bacterial hive infestation linked to bee colony collapse after previous work in a fruit-fly model suggested that pesticides reduces bees' immunity and their ability to fight back against these harmful pathogens.
Writing in the Nature journal ISME, the team combined their expertise in probiotics and bee biology to supplement honey bee food with probiotics, in the form a BioPatty, in their experimental apiaries. The aim was to see what effect probiotics would have on honey bee health.
"Probiotics aren't just for humans," commented Gregor Reid, PhD, Professor at Western's Schulich School of Medicine & Dentistry and Endowed Chair in Human Microbiome and Probiotics at Lawson. "Our idea was that if you could use beneficial microbes to stimulate the immune response or attack the pathogens that are infecting the hives, then maybe we can help save the bees."
Reid told NutraIngredients that the potential for probiotics to reduce honey bee colony collapse is ‘real’, but noted that products currently on the market are mostly ‘based on theory instead of hard science.’
“We want to get it right and understand which strains work, why they work and how we can optimise the effect not just to counter pathogens and pesticides, but to provide beekeepers with practical solutions,” he said.
“We worry about potential wars in the Middle East and Korea, but if the bees die we will not be here to worry about conflict. Long may they fly.”
The current study shows the benefit of the probiotic patty to protect bee colonies against colony collapse linked to a common disease.
During the experiment hives became inadvertently infected with American Foulbrood, a common hive disease produced by the bacteria P. larvae, which would typically cause the bees to die.
"Bee colonies are really interesting little microcosms of biology. There are lots of individuals bees, but they are all genetically related and they are living in a close confined space," explained Graham Thompson, PhD, Associate Professor in the Faculty of Science at Western who studies the biology and social behaviour of bees.
"They are all very susceptible to contagious disease and they are demographically disposed to outbreaks."
The Canadian team reported that in the bee hives treated with probiotics, the pathogen load was reduced by 99%, and the survival-rate of the bees increased significantly.
When they examined the bees in the lab, they also found that there was increased immunity against the bacteria that causes American Foulbrood in the bees treated with the probiotics.
"The results from our study demonstrated that probiotic supplementation could increase the expression of a gene called Defensin-1 - a key antimicrobial peptide shown to play a pivotal role in honey bee defence against P. larvae infection," said Brendan Daisley, lead author on the paper.
“Alongside these findings, we also observed an increase in pathogen clearance and overall survival of honey bee larvae.”
According to Reid and his colleagues, another interesting observation was that the bees given the BioPatty, but no probiotic, were the most susceptible, even more so than bees that were given nothing at all.
This suggests that there be a negative outcome to the common practise of supplementing bee colonies with extra food as it could stimulate the pathogens to proliferate, they added.
"Long term we hope to add a viable, practical and available treatment alternative to chemicals and antibiotics that beekeepers can readily adopt into their bee-keeping habits to help prevent colony collapse," said Thompson.