American foulbrood (AFB) is amongst the most dangerous of bee diseases, affecting many honey bee colonies worldwide each year.L. plantarum. The growth dynamic of both strains was similar whereby no significant differences were found (Fig. 1). Decrease of pH was significantly faster in L. plantarum from the 8 th to 24 th hour of growth (p < 0.001) in comparison to L. brevis, in accordance with significantly higher production of lactic acid by L. plantarum. Homofermentative L. plantarum produced high concentration of lactic acid (269.2 ± 14.30 mmol.l -1 ) and lower concentrations of acetic (78.1 ± 4.83 mmol.l -1 ), acetoacetic (23.4 ± 2.08 mmol.l -1 ) andpropionic acid (17.9 ± 7.05 mmol.l -1 ). Heterofermentative L. brevis produced in the highest concentrations of acetic (73.9 ± 5.87 mmol.l -1 ), lactic (42.9 ± 3.29 mmol.l -1 ), and acetoacetic acid (27.2 ± 1.69 mmol.l -1 ).All these properties are good prerequisites for the use of both strains for the prevention of P. larvae infection in honey bees, but further studies are necessary.
ABSTRACT:The aim of this study was to characterise the genera and species of Gram-positive aerobic and microaerophilic microorganisms isolated from pathological processes and lesions in horses. In the period 2009-2014, 449 clinical samples from horses were examined. Of these, 229 (51%) were collected from the respiratory tract, 121 (26.9%) from the skin, 40 (8.9%) from the gastrointestinal tract, 40 (8.9%) from the eyes, 8 (1.8%) from the urinary tract, 6 (1.3%) from the musculoskeletal system, 4 (0.9%) from the lymphatic system and 1 (0.2%) from milk. The isolates were presumptively identified phenotypically, and identification was confirmed by molecular phenotypic MALDI-TOF. The most frequently detected strains (n = 330) were Staphylococcus spp., Streptococcus spp., Corynebacterium spp. with prevalence rates of 37.2%, 23.4% and 7.6%, respectively. In addition, 24 other taxa were identified, including Enterococcus spp., Bacillus spp., Trueperella pyogenes, Aerococcus viridans, Dermatophilus congolensis, Lysinibacillus fusiformis, Nocardiopsis alba and Streptomyces spp. Most of these are described as opportunistic pathogens of animals, including horses. Antibiotic susceptibility was tested using the disc diffusion method. Florfenicol and amoxycillin with clavulanic acid were the most effective antibiotics. The susceptibility to florfenicol was 100% for tested strains of Bacillus spp., Lysinibacillus spp., Corynebacterium spp., Dermatophilus congolensis, Streptococcus spp., Enterococcus spp., Aerococcus spp., Nocardiopsis alba and Trueperella pyogenes. The susceptibilities of Staphylococcus aureus and other staphylococci to florfenicol were 96.2% and 98.5% in tested strains, respectively. Amoxycillin with clavulanic acid exhibited 100% effectiveness against Corynebacterium spp., Dermatophilus congolensis, Streptococcus spp., Aerococcus spp., Enterococcus spp., Streptomyces spp., Nocardiopsis alba and Trueperella pyogenes tested strains. The susceptibilities of Staphylococcus aureus, other staphylococci and Bacillus/Lysinibacillus spp. to amoxycillin with clavulanic acid were 89.8%, 98.8% and 20.0% of tested strains, respectively.
The development of resistance in the housefly (Musca domestica) to azamethiphos, pirimiphosmethyl, bendiocarb, permethrin, cypermethrin and deltamethrin was investigated on pig farms over a 4-year period. The results obtained in laboratory tests were compared with those obtained under practical conditions in pig houses. An intensive use of insecticides induced resistance in the course of 2 to 3 seasons. The classic spray regimes of insecticides led to the development of high resistance after one or two seasons. Integrated control, based on rotational application -organophosphate, pyrethroid, carbamate, pyrethroid, organophosphate -retained the resistance at low to moderate levels. Because of the variability of resistance factor (RF) in the field populations observed, the monofactorial and rotational selective pressure of insecticides was investigated. The rotational application of azamethiphos and permethrin or cypermethrin having sufficient insecticidal effect retained the resistance at low to moderate levels over a 4-year period. Although the alternation of insecticides cannot prevent the development of resistance, it can extend several times the period of their successful application on farms. This knowledge can help to formulate the strategies for fly control programmes.
Scientists around the world are focusing their interest on the use of probiotics in honey bees as an alternative method of prophylaxis against causative agents of both American and European foulbrood. In our study we tested inhibitory activity against Paenibacillus larvae and the biofilm formation activity by various lactic acid bacteria isolated from honey bee guts or fresh pollen samples in the presence of different sugars added to the cultivation media. In addition, we tested the probiotic effect of a newly selected Apilactobacillus kunkeei V18 in an in situ experiment in bee colonies. We found antibacterial activity against P. larvae in four isolates. Biofilm formation activity of varying intensity was noted in six of the seven isolates in the presence of different sugars. The strongest biofilm formation (OD570 ≥ 1) was noted in A. kunkeei V18 in the presence of fructose; moreover, this isolate strongly inhibited the growth of P. larvae under laboratory conditions. Inhibition of P. larvae and Melissococcus plutonius by A. kunkeei V18 in situ was confirmed in a pilot study.
American foulbrood is a dangerous world-wide spread disease of honey bees caused by the Paenibacillus larvae bacterium. Antibiotic treatments are less effective and leave residues in bee products. It is therefore necessary to find an alternative, especially using natural ingredients such as plant essential oils, probiotics, fatty or organic acids. Two strains of P. larvae were used for this study: CCM 4488, a strain from the Czech collection of micro-organisms and a Slovak field strain which was isolated from infected bee combs and characterized on the basis of biochemical properties. Plant essential oils of sage (Salvia officinalis), anise (Pimpinella anisum), oregano (Origanum vulgare), caraway (Carum carvi), thyme (Thymus vulgaris), rosemary (Rosmarinum officinalis), clove (Syzygium aromaticum), camomile (Chamomilla recutita) and fennel (Foeniculum vulgare) were used for the testing of the inhibitory activity against P. larvae. Essential oils at amounts of 5 µl and 10 µl were applied to sterile discs on MYPGP agar; inhibition zone diameters were measured after 24-h incubation at 37 °C. The strongest inhibitory activity against both P. larvae strains was noted in case of the essential oils from oregano, thyme and clove; essential oils from camomile, rosemary and fennel showed no or weak antibacterial activity. Medium strong inhibition activity was recorded in case of previously untested essential oil from Carum carvi. There was a difference in sensitivity of both tested strains to essential oils. Our study confirmed that some essential oils can be used in the prevention of American foulbrood but further experiments aimed at their influence on physiological intestinal microflora of honey bees must be performed.
Apiculture is an important economy sector, facing a real health crisis. Honeybees, as well as other insect pollinator populations have been in decline over recent decades, and diseases are one of the principal challenges. To face this situation, public and private veterinary services are needed to manage surveillance, control, eradication and prevention measures of honeybee diseases within their territories, in close collaboration with beekeepers and farmers. It is necessary urgently to clarify the current problems and threats to apiculture in the public health sector. Due to possible interactions between bee health and production, the negative effects of environmental xenobiotics and climate change, this field must be considered as an interdisciplinary research issue. Moreover, honeybee veterinary medicine is increasingly engaged in the One Health approach, due to the possibility that the poor health of honeybee colonies affects human life. This review identified the key veterinarian roles, gaps in their higher education curriculum, as well as the necessity for research linkage between expectations and professional perspectives.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.