Effect of Lactobacillus johnsonii CRL1647 on different parameters of honeybee colonies and bacterial populations of the bee gut

Abstract

Lactobacillus johnsonii CRL1647, isolated from the intestinal tract of a worker-bee in Salta, Argentina, was delivered to Apis mellifera L. honey bee colonies according to two different administration schedules: 1×10(5) cfu/ml every 15 days (2011) or monthly (2012). The effect of each treatment on the bee-colony performance was monitored by measuring honey production, and the prevalence of varroasis and nosemosis. Worker bees from each assay were randomly captured 3 days after administration and assayed for the following intestinal culturable and defined bacterial populations: total aerobic microorganisms, Bacillus spp. spores, Lactobacillus spp., Enterococcus spp. and enterobacteria. Interestingly, both treatments generated a similar increase in honey production in treated colonies compared to controls: 36.8% (every 15 days) and 36.3% (monthly). Nosema index always exhibited a reduction when lactobacilli were administered; in turn, Varroa incidence was lower when the lactobacilli were administered once a month. Moreover, the administration of L. johnsonii CRL1647 every 15 days produced an increase in the total number of aerobic microorganisms and in bacteria belonging to the genera Lactobacillus and Enterococcus; at the same time, a decrease was observed in the number of total spores at the end of the treatment. The number of enterobacteria was constant and remained below that of control hives at the end of the assay. On the other hand, the delivery of lactobacilli once a month only showed an increase in the number of bacteria belonging to the genus Lactobacillus; meanwhile, viable counts of the remaining microorganisms assayed were reduced. Even though it seems that both treatments were similar, those bee colonies that received L. johnsonii CRL1647 every 15 days became so strong that they swarmed.

Deleterious Interaction Between Honeybees (Apis mellifera) and its Microsporidian Intracellular Parasite Nosema ceranae Was Mitigated by Administrating Either Endogenous or Allochthonous Gut Microbiota Strains

“…In murine models, both bacterial and yeast probiotic strains have also proven their effectiveness against intracellular parasites and showed positive improvement of the health of host (Alak et al, 1997(Alak et al, , 1999Benyacoub et al, 2005;Humen et al, 2005;Shukla et al, 2008;Dinleyici et al, 2011). Concerning honey bees, endogenous gut bacteria belonging to Lactobacilliaceae, Bifidobacteriaceae, and Acetobacteraceae families have been found to play an antagonistic role against N. ceranae, either in caged bee trial or in field conditions, by reducing the spore load (Sabaté et al, 2012;Audisio et al, 2015;Baffoni et al, 2016;Corby-Harris et al, 2016).…”

Early gut colonizers shape parasite susceptibility and microbiota composition in honey bee workers

“…50-53); these effects may involve key metabolic and detoxification genes, such as cytochrome P450s (54)(55)(56). Their gut microbiota also likely mediate stress responses, and bacterial strains cultivated from honey bees could be harnessed as probiotic mitigators of stress (30)(31)(32)(33)57).…”

A Pediococcus strain to rescue honeybees by decreasing Nosema ceranae- and pesticide-induced adverse effects

“…Administration of selected microorganisms, in this dysbiotic context, could thus represent beneficial microbes that could be used as probiotics. If probiotics are commonly used in vertebrates (Crotti et al, 2012), few studies have focused on their impact on honeybee health (Audisio et al, 2015;Baffoni et al, 2016;El Khoury et al, 2018;Gaggìa et al, 2018;Ptaszyńska et al, 2016).…”