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Evaluation of enzymatic effects of some strains of Entomopathogenic fungi studied on hard ticks (Ixodes ricinus)
2017
Pirali, Yaser | Karimi, Isaac | Nabian, Sedigheh | Zeilabi, Vahidreza
BACKGROUND: Biological control of parasites by using entomopathogen fungi is the one of the recommended ways to control them instead of using the chemical agents. Entomopathogen fungi are not pathogenic for animals and plants, while ticks are one of the most important parasites of animals that can transmit very important microbial pathogens. Ixodes ricinus is a hard tick that infests animals and human. OBJECTIVES: This study demonstrated enzyme assay of entomopathogen fungi hosted on Ixodes ricinus. METHODS: Enzymatic activities of chitinase, lipase and protease of fungal structures on the killed tick bodies have been assayed by standard sphectrophotometric methods. RESULTS: Chitinase, lipase and protease activities showed significant differences among different fungal strains (p<0.05). This research, which was done for first time in Iran demonstrated the effect of some enzymes which affect on acaricidal properties of native strain of entomopathogenic fungi in Iran. CONCLUSIONS: This study reveals the relationship between enzyme level of fungal strains and the possibility of selecting more effective strains of entomopathogenic fungi
Afficher plus [+] Moins [-]Assessment of Bdellovibrio bacteriovorus 109J killing of Moraxella bovis in an in vitro model of infectious bovine keratoconjunctivitis
2011
Boileau, Mélanie J. | Clinkenbeard, Kenneth D. | Iandolo, John J.
The objective of this study was to determine the potential of Bdellovibrio bacteriovorus 109J as an alternative non-chemotherapeutic treatment of infectious bovine keratoconjunctivitis (IBK). To accomplish this, various parameters of B. bacteriovorus predation of Moraxella bovis were determined in vitro. Initial passage of B. bacteriovorus using M. bovis as prey required 10 d for active cultures to develop compared with 2 d for culture on normal Escherichia coli prey; however by the 5th passage, time to active predatory morphology was reduced to 2 d. This high passage B. bacteriovorus culture [1 × 10(10) plaque forming units (PFU)/mL] killed 76% of M. bovis [1 × 10(7) colony forming units (CFU)/mL] present in suspension broth in a 4 h assay. The minimal level of M. bovis supporting B. bacteriovorus predation was 1 × 10(4) CFU/mL. To assess the ability of B. bacteriovorus to kill M. bovis on an epithelial surface mimicking IBK, an in vitro assay with Madin-Darby bovine kidney (MDBK) cells inoculated with 4 × 10(7) CFU/mL M. bovis was used. Treatment with a B. bacteriovorus suspension (1.6 × 10(11) PFU/mL) decreased adherence of M. bovis to MDBK cells by 6-fold at 12 h of treatment, as well as decreased the number of unattached M. bovis cells by 1.4-fold. This study demonstrates that B. bacteriovorus has potential as an effective biological control of M. bovis at levels likely present in IBK-infected corneal epithelia and ocular secretions.
Afficher plus [+] Moins [-]Characterization of Egyptian Beauveria bassiana Strain for Biocontrol of Musca domestica
2023
Menna A. El-Geneady | Azza M. Abdel-Wahab | Marwa M. Khalifa | Shimaa Abdel-Radi | Ahmed M. Abdel-Gawad
Beauveria spp., an entomopathogenic fungus, has recently been widely used as a biocontrol agent of house fly populations to evade the critical effects of chemical insecticides on humans, animals, and the natural ecosystem. In the presented study, different types of fungi were isolated from house flies collected from various locations in different Egyptian governorates between 2021 and 2022. The flies were caught in garbage dumps, dairy and meat production units on cattle farms and poultry farms. The entomopathogenic fungi were identified morphologically and genetically, showing that the isolate was molecularly identified as Beauveria bassiana. This efficacy of the isolated fungal strain against the house fly, M. domestica, was estimated using laboratory bioassay by the immersion method. The isolated fungal strain successfully induced fatal changes with a high mortality rate in the laboratory-reared house flies, which confirms the scientific world researches which has been carried out. The achieved result showed a direct correlation between fungal concentrations and the mortality rate, which reached up to 99.16 %. They also exhibited great destruction and a direct relationship between the increase in spore concentration and the degree of overall DNA genotoxic damage in the exposed fly's DNA to Beauveria bassiana. Beauveria bassiana MN960454.1 can be used as an efficient way for controlling house fly biologically reached up to 99.16 %. Thus, it is recommended to apply Beauveria spp. as a spray in house fly breeding areas.
Afficher plus [+] Moins [-]Экологический мониторинг водоисточников и эффективность использования улучшенной воды в условиях свиноводческого комплекса
2009
Medvedskij, V.A. | Karas, A.V. | Zhelezko, A.F., Vitebsk State Academy of Veterinary Medicine (Belarus)
In the first time has been lead the ecological monitoring of sources of water supply of a pig-breeding complex and adjoining human settlements on seasons of year and to develop a method of improvement of water quality for giving to drink pigs. Scientific novelty consists that for the first time in Belarus ecological monitoring of sources of water supply in the conditions of a pig-breeding complex and human settlements adjoining to it is made. Influence of large pig-breeding object on quality of water of the occluded water sources is studied. It is positioned microbial contamination waters depending on remoteness from cattle-breeding object and a season of year
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