scholarly journals Novel probiotic approach to counter Paenibacillus larvae infection in honey bees

2019 ◽  
Vol 14 (2) ◽  
pp. 476-491 ◽  
Author(s):  
Brendan A. Daisley ◽  
Andrew P. Pitek ◽  
John A. Chmiel ◽  
Kait F. Al ◽  
Anna M. Chernyshova ◽  
...  
Keyword(s):  
Honey Bee ◽  
Honey Bees ◽  
Lactobacillus Rhamnosus ◽  
Paenibacillus Larvae ◽  
Causative Organism ◽  
Immune Genes ◽  
Pathogen Load ◽  
Probiotic Lactobacilli ◽  
Honey Bee Larvae

Abstract American foulbrood (AFB) is a highly virulent disease afflicting honey bees (Apis mellifera). The causative organism, Paenibacillus larvae, attacks honey bee brood and renders entire hives dysfunctional during active disease states, but more commonly resides in hives asymptomatically as inactive spores that elude even vigilant beekeepers. The mechanism of this pathogenic transition is not fully understood, and no cure exists for AFB. Here, we evaluated how hive supplementation with probiotic lactobacilli (delivered through a nutrient patty; BioPatty) affected colony resistance towards a naturally occurring AFB outbreak. Results demonstrated a significantly lower pathogen load and proteolytic activity of honey bee larvae from BioPatty-treated hives. Interestingly, a distinctive shift in the microbiota composition of adult nurse bees occurred irrespective of treatment group during the monitoring period, but only vehicle-supplemented nurse bees exhibited higher P. larvae loads. In vitro experiments utilizing laboratory-reared honey bee larvae showed Lactobacillus plantarum Lp39, Lactobacillus rhamnosus GR-1, and Lactobacillus kunkeei BR-1 (contained in the BioPatty) could reduce pathogen load, upregulate expression of key immune genes, and improve survival during P. larvae infection. These findings suggest the usage of a lactobacilli-containing hive supplement, which is practical and affordable for beekeepers, may be effective for reducing enzootic pathogen-related hive losses.

scholarly journals Response of in vitro reared honey bee larvae to various doses of Paenibacillus larvae larvae spores

Apidologie ◽  
1998 ◽  
Vol 29 (6) ◽  
pp. 569-578 ◽  
Author(s):  
Camilla J. Brødsgaard ◽  
Wolfgang Ritter ◽  
Henrik Hansen
Keyword(s):  
Honey Bee ◽  
Paenibacillus Larvae ◽  
Honey Bee Larvae

scholarly journals Anti-Virulence Strategy against the Honey Bee Pathogenic Bacterium Paenibacillus larvae via Small Molecule Inhibitors of the Bacterial Toxin Plx2A

Toxins ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 607
Author(s):  
Julia Ebeling ◽  
Franziska Pieper ◽  
Josefine Göbel ◽  
Henriette Knispel ◽  
Michael McCarthy ◽  
...  
Keyword(s):  
Small Molecules ◽  
Honey Bee ◽  
Small Molecule ◽  
Bacterial Infections ◽  
Small Molecule Inhibitors ◽  
Paenibacillus Larvae ◽  
Bacterial Toxin ◽  
American Foulbrood ◽  
Honey Bee Larvae

American Foulbrood, caused by Paenibacillus larvae, is the most devastating bacterial honey bee brood disease. Finding a treatment against American Foulbrood would be a huge breakthrough in the battle against the disease. Recently, small molecule inhibitors against virulence factors have been suggested as candidates for the development of anti-virulence strategies against bacterial infections. We therefore screened an in-house library of synthetic small molecules and a library of flavonoid natural products, identifying the synthetic compound M3 and two natural, plant-derived small molecules, Acacetin and Baicalein, as putative inhibitors of the recently identified P. larvae toxin Plx2A. All three inhibitors were potent in in vitro enzyme activity assays and two compounds were shown to protect insect cells against Plx2A intoxication. However, when tested in exposure bioassays with honey bee larvae, no effect on mortality could be observed for the synthetic or the plant-derived inhibitors, thus suggesting that the pathogenesis strategies of P. larvae are likely to be too complex to be disarmed in an anti-virulence strategy aimed at a single virulence factor. Our study also underscores the importance of not only testing substances in in vitro or cell culture assays, but also testing the compounds in P. larvae-infected honey bee larvae.

scholarly journals Combined Toxicity of Insecticides and Fungicides Applied to California Almond Orchards to Honey Bee Larvae and Adults

Insects ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 20 ◽  
Author(s):  
Andrea Wade ◽  
Chia-Hua Lin ◽  
Colin Kurkul ◽  
Erzsébet Ravasz Regan ◽  
Reed M. Johnson
Keyword(s):  
Larval Development ◽  
Honey Bee ◽  
Honey Bees ◽  
Pesticide Exposure ◽  
Larval Mortality ◽  
Combined Toxicity ◽  
Pollination Services ◽  
Almond Orchards ◽  
Honey Bee Larvae

Beekeepers providing pollination services for California almond orchards have reported observing dead or malformed brood during and immediately after almond bloom—effects that they attribute to pesticide exposure. The objective of this study was to test commonly used insecticides and fungicides during almond bloom on honey bee larval development in a laboratory bioassay. In vitro rearing of worker honey bee larvae was performed to test the effect of three insecticides (chlorantraniliprole, diflubenzuron, and methoxyfenozide) and three fungicides (propiconazole, iprodione, and a mixture of boscalid-pyraclostrobin), applied alone or in insecticide-fungicide combinations, on larval development. Young worker larvae were fed diets contaminated with active ingredients at concentration ratios simulating a tank-mix at the maximum label rate. Overall, larvae receiving insecticide and insecticide-fungicide combinations were less likely to survive to adulthood when compared to the control or fungicide-only treatments. The insecticide chlorantraniliprole increased larval mortality when combined with the fungicides propiconazole or iprodione, but not alone; the chlorantraniliprole-propiconazole combination was also found to be highly toxic to adult workers treated topically. Diflubenzuron generally increased larval mortality, but no synergistic effect was observed when combined with fungicides. Neither methoxyfenozide nor any methoxyfenozide-fungicide combination increased mortality. Exposure to insecticides applied during almond bloom has the potential to harm honey bees and this effect may, in certain instances, be more damaging when insecticides are applied in combination with fungicides.

scholarly journals Horizontal Honey-Bee Larvae Rearing Plates Can Increase the Deformation Rate of Newly Emerged Adult Honey Bees

Insects ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 603
Author(s):  
Juyeong Kim ◽  
Kyongmi Chon ◽  
Bo-Seon Kim ◽  
Jin-A Oh ◽  
Chang-Young Yoon ◽  
...  
Keyword(s):  
Apis Mellifera ◽  
Honey Bee ◽  
Honey Bees ◽  
Deformation Rate ◽  
Sublethal Effects ◽  
Horizontal Position ◽  
Control Groups ◽  
Honey Bee Larvae ◽  
Ideal Method

Rearing honey bee larvae in vitro is an ideal method to study honey bee larval diseases or the toxicity of pesticides on honey bee larvae under standardized conditions. However, recent studies reported that a horizontal position may cause the deformation of emerged bees. Accordingly, the purpose of this study was to evaluate the emergence and deformation rates of honey bee (Apis mellifera ligustica) larvae reared in horizontal and vertical positions. The study was conducted under the same laboratory conditions with three experimental groups, non-capped or capped horizontal plates and capped vertical plates. However, our results demonstrated that the exhibited adult deformation rates of the horizontal plates were significantly higher (27.8% and 26.1%) than those of the vertical plates (11.9%). In particular, the most common symptoms were deformed wings and an abnormal abdomen in the horizontal plates. Additionally, adults reared on horizontal plates were substantially smaller (10.88 and 10.82 mm) than those on vertical plates (11.55 mm). Considering these conclusions, we suggest that a vertical rearing method is more suitable when considering the deformation rates of the control groups to verify the sublethal effects of pesticides on honey bees.

scholarly journals Inhibitory effect of indole analogs against Paenibacillus larvae, the causal agent of American foulbrood disease

2017 ◽  
Vol 17 (5) ◽  
Author(s):  
Israel Alvarado ◽  
Joseph W Margotta ◽  
Mai M Aoki ◽  
Fernando Flores ◽  
Fresia Agudelo ◽  
...  
Keyword(s):  
Honey Bee ◽  
Spore Germination ◽  
Inhibitory Effect ◽  
Antagonistic Effect ◽  
Paenibacillus Larvae ◽  
American Foulbrood ◽  
Bacterial Proliferation ◽  
American Foulbrood Disease ◽  
Honey Bee Larvae

Abstract Paenibacillus larvae, a Gram-positive bacterium, causes American foulbrood (AFB) in honey bee larvae (Apis mellifera Linnaeus [Hymenoptera: Apidae]). P. larvae spores exit dormancy in the gut of bee larvae, the germinated cells proliferate, and ultimately bacteremia kills the host. Hence, spore germination is a required step for establishing AFB disease. We previously found that P. larvae spores germinate in response to l-tyrosine plus uric acid in vitro. Additionally, we determined that indole and phenol blocked spore germination. In this work, we evaluated the antagonistic effect of 35 indole and phenol analogs and identified strong inhibitors of P. larvae spore germination in vitro. We further tested the most promising candidate, 5-chloroindole, and found that it significantly reduced bacterial proliferation. Finally, feeding artificial worker jelly containing anti-germination compounds to AFB-exposed larvae significantly decreased AFB infection in laboratory-reared honey bee larvae. Together, these results suggest that inhibitors of P. larvae spore germination could provide another method to control AFB.

scholarly journals Comparing Survival of Israeli Acute Paralysis Virus Infection among Stocks of U.S. Honey Bees

Insects ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 60
Author(s):  
Shilpi Bhatia ◽  
Saman S. Baral ◽  
Carlos Vega Melendez ◽  
Esmaeil Amiri ◽  
Olav Rueppell
Keyword(s):  
Honey Bee ◽  
Honey Bees ◽  
Virus Infections ◽  
Israeli Acute Paralysis Virus ◽  
Immune Genes ◽  
Starting Point ◽  
Bee Health ◽  
Honey Bee Health ◽  
Survival Differences ◽  
Paralysis Virus

Among numerous viruses that infect honey bees (Apis mellifera), Israeli acute paralysis virus (IAPV) can be linked to severe honey bee health problems. Breeding for virus resistance may improve honey bee health. To evaluate the potential for this approach, we compared the survival of IAPV infection among stocks from the U.S. We complemented the survival analysis with a survey of existing viruses in these stocks and assessing constitutive and induced expression of immune genes. Worker offspring from selected queens in a common apiary were inoculated with IAPV by topical applications after emergence to assess subsequent survival. Differences among stocks were small compared to variation within stocks, indicating the potential for improving honey bee survival of virus infections in all stocks. A positive relation between worker survival and virus load among stocks further suggested that honey bees may be able to adapt to better cope with viruses, while our molecular studies indicate that toll-6 may be related to survival differences among virus-infected worker bees. Together, these findings highlight the importance of viruses in queen breeding operations and provide a promising starting point for the quest to improve honey bee health by selectively breeding stock to be better able to survive virus infections.

scholarly journals Toxicity Evaluation of Selected Plant Water Extracts on a Honey Bee (Apis mellifera L.) Larvae Model

Animals ◽  
2022 ◽  
Vol 12 (2) ◽  
pp. 178
Author(s):  
Roksana Kruszakin ◽  
Paweł Migdal
Keyword(s):  
Apis Mellifera ◽  
Honey Bee ◽  
Honey Bees ◽  
Larval Rearing ◽  
Distilled Water ◽  
Chelidonium Majus ◽  
Freeze Dried ◽  
Study Laboratory ◽  
The Impact

So far, larval rearing in vitro has been an important method in the assessment of bee toxicology, particularly in pesticide risk assessment. However, natural products are increasingly used to control honey bee pathogens or to enhance bee immunity, but their effects on honey bee larvae are mostly unknown. In this study, laboratory studies were conducted to determine the effects of including selected aqueous plant infusions in the diet of honey bee (Apis mellifera L.) larvae in vitro. The toxicity of infusions from three different plant species considered to be medicinal plants was evaluated: tansy (Tanacetum vulgare L.), greater celandine (Chelidonium majus L.), and coriander (Coriandrum sativum L.). The impact of each on the survival of the larvae of honey bees was also evaluated. One-day-old larvae were fed a basal diet consisting of distilled water, sugars (glucose and fructose), yeast extract, and freeze-dried royal jelly or test diets in which distilled water was replaced by plant infusions. The proportion of the diet components was adjusted to the age of the larvae. The larvae were fed twice a day. The experiment lasted seven days. Significant statistical differences in survival rates were found between groups of larvae (exposed or not to the infusions of tansy, greater celandine, and coriander). A significant decrease (p < 0.05) in the survival rate was observed in the group with the addition of a coriander herb infusion compared to the control. These results indicate that plant extracts intended to be used in beekeeping should be tested on all development stages of honey bees.

In vitro antagonistic potential of gut bacteria isolated from indigenous honey bee race of Saudi Arabia against Paenibacillus larvae

2020 ◽  
Vol 59 (5) ◽  
pp. 825-833 ◽  
Author(s):  
Ahmad Al-Ghamdi ◽  
Amal Abdullah Al-Abbadi ◽  
Khalid Ali Khan ◽  
Hamed Ali Ghramh ◽  
Ashraf M. Ahmed ◽  
...  
Keyword(s):  
Saudi Arabia ◽  
Honey Bee ◽  
Gut Bacteria ◽  
Paenibacillus Larvae ◽  
Antagonistic Potential

scholarly journals Reclassification of Paenibacillus larvae subsp. pulvifaciens and Paenibacillus larvae subsp. larvae as Paenibacillus larvae without subspecies differentiation

2006 ◽  
Vol 56 (3) ◽  
pp. 501-511 ◽  
Author(s):  
Elke Genersch ◽  
Eva Forsgren ◽  
Jaana Pentikäinen ◽  
Ainura Ashiralieva ◽  
Sandra Rauch ◽  
...  
Keyword(s):  
Honey Bee ◽  
Paenibacillus Larvae ◽  
Rrna Gene ◽  
Subspecies Differentiation ◽  
Field Isolates ◽  
Sds Page ◽  
Clear Identification ◽  
Bee Colonies ◽  
Honey Bee Larvae ◽  
Reference Strains

A polyphasic taxonomic study of the two subspecies of Paenibacillus larvae, Paenibacillus larvae subsp. larvae and Paenibacillus larvae subsp. pulvifaciens, supported the reclassification of the subspecies into one species, Paenibacillus larvae, without subspecies separation. Our conclusions are based on the analysis of six reference strains of P. larvae subsp. pulvifaciens and three reference strains and 44 field isolates of P. larvae. subsp. larvae. The latter originated from brood or honey of clinically diseased honey bee colonies or from honey of both clinically diseased and asymptomatic colonies from Sweden, Finland and Germany. Colony and spore morphology, as well as the metabolism of mannitol and salicin, did not allow a clear identification of the two subspecies and SDS-PAGE of whole-cell proteins did not support the subspecies differentiation. For genomic fingerprinting, repetitive element-PCR fingerprinting using ERIC primers and PFGE of bacterial DNA were performed. The latter method is a high-resolution DNA fingerprinting method proven to be superior to most other methods for biochemical and molecular typing and has not previously been used to characterize P. larvae. ERIC-PCR identified four different genotypes, while PFGE revealed two main clusters. One cluster included most of the P. larvae subsp. larvae field isolates, as well as all P. larvae subsp. pulvifaciens reference strains. The other cluster comprised the pigmented variants of P. larvae subsp. larvae. 16S rRNA gene sequences were determined for some strains. Finally, exposure bioassays demonstrated that reference strains of P. larvae subsp. pulvifaciens were pathogenic for honey bee larvae, producing symptoms similar to reference strains of P. larvae subsp. larvae. In comparison with the type strain for P. larvae subsp. larvae, ATCC 9545T, the P. larvae subsp. pulvifaciens strains tested were even more virulent, since they showed a shorter LT100. An emended description of the species is given.

Sign in / Sign up

Export Citation Format

Share Document