|
|
Inhibition of the etiological agent of American foulbrood disease using selected essential oils
ZÁLABSKÁ, Adéla
Americal foulbrood disease, caused by etiological agent Paenibacillus larvae is serious disease which affects honey bee that is prohibited to treat with antibiotic in the Czech Republic. If the disease occurs in hive, it is a legal requirement to burn the hive. Essential oils have antimicrobial aktivity and their use can help fighting this dangerous disease. The aim of the bachelor thesis was to verify the bactericidal effect of selected essential oils on the causative agent of the americal foulbrood disease P. Larvae. Another stated aim was to determine the minimum inhibitory and bactericidal concentrations of the selected essential oils. A total of 11 essential oils were used and evaluated both alone and in combination with other essential oils. The evaluation was carried oud on microtiter plates using spectophotometer and on agar medium in petri dishes. The most effective essential oil was garlic oil (Allium sativum bulb oil), which had minimum and bactericidal concentration values of 32 ?l/mg. Other very effective plant essential oils include cinnamon essential oil (Cinnamomum zeylanicum bark oil). The least effective essential oils are carrot oil (Daucus carota sativa seed oil), thyme oils (Thymus serpyllum oil, Thymus vulgaris flower/leaf oil) or oregano oil (Origanum vulgare).
|
|
|
Insect pollinators issues and alternative methods of control of fungal, bacterial, and parasitic diseases of bees
MRÁZ, Petr
This Ph.D. thesis is focused on the importance of insect pollinators and pointed out to their loss due to intensive agriculture. Great attention is paid to the honey bee as the main pollinator, especially to the issue of quality nutrition of bee colonies in connection with the support of detoxification of pesticides. Furthermore, the main effort is devoted to alternative possibilities of control of selected bee pathogens and research of their prevalence in the Czech Republic. The work is divided into two main parts: a detailed background research and an experimental part consisting of six subchapters with results from my own research studies. The first study deals with the effect of pollination on the qualitative and quantitative yield parameters of honeysuckle. Several pollination variants were tested and the best result in all monitored parameters was achieved by the pollination with natural pollinators. Variants of manual pollination and without pollination caused uneven maturation of fruits and lower yields. Furthermore, the diversity and abundance of pollinators in the vicinity of this crop were observed and the most suitable pollinators identified which appear to be bumblebees and the honey bee. The second study deals with the impact of agricultural intensity on the diversity and abundance of pollinators in the landscape. Localities with organic and conventional management regimes were compared. Significantly higher diversity and abundance of pollinators was recorded in the locality managed by organic farming. In addition, the contamination load of pesticide residues in bee's body was also monitored. Residues of several pesticides were detected at the site with conventional agriculture, while none of them were detected at the site with organic farming. The third study examines the effect of nutrition, specifically phenolic substances, on the ability of bees to detoxify the pesticide to which they have been exposed. In the experiment, the bees in the cages were fed with a mixture of selected polyphenols, commonly found in pollen, and the pesticide thiacloprid. Mortality and daily feed consumption were monitored for 14 days, and the expression level of detoxification genes was analyzed at specified intervals. Phenolic substances have been shown to have a positive effect on the lifespan of intoxicated bees, as well as higher feed consumption, which may indicate an increased need for these substances. In contrast, the increased expression of detoxification genes was not confirmed. Other studies focus on honey bee pathogens. One of them monitors the occurrence and prevalence of selected major bee pathogens in the Czech Republic and compares different types of habitats, such as urban areas, agriculturally intensively cultivated areas and protected natural areas. Surprisingly, the most often detected pathogen was Lotmaria passim. From the viral diseases, the highest rate of occurrence had DWV complex and ABPV. In general, more eukaryotic pathogens were found in cities and agricultural landscapes. On the contrary, more viral diseases were recorded in the protected natural area. The fifth subchapter consists of 4 publications and deals with the use of essential oils to control the Varroa destructor mite and the entomopathogenic fungus Ascosphaera apis. The first publication compares the growth and development of the fungus A. apis on different culture media and proposes a new medium with the addition of bee brood, on which the greatest sporulation was recorded. Another 2 publications deal with the fungicidal effect of selected essential oils in laboratory conditions. The best results were shown by essential oils of thyme, cedar wood, cloves and cinnamon. The fourth publication deals with the acaricidal effect of selected essential oils on the V. destructor mites and at the same time evaluate the toxicity of these oils to adult bees. Based on these results, essential oils with the highest LD50 to bees / LD50 to mites ratio (sele
|
|
|
Monitoring of Paenibacillus larvae, Melissococcus plutonius and Ascosphaera apis pathogens in honeybee colonies in the Czech Republic
JOSKOVÁ, Markéta
The aim of this thesis was to summarize the theoretical informations about biology of honeybees and bacteries Paenibacillus larvae and Melissococcus plutonius and parasitic fungi Ascosphaera apis. This organisms attack bee larvae and cause bee diseases. The major part of this thesis was focused on the evaluation of the occurrence of these pathogens in various places in Czech Republic by isolating bee DNA from more than 200 bee samples from 50 locations within whole Czech Republic. Detection pathogens was performed using PCR method. There were 3 samples positive for Paenibacillus larvae and 4 positive for Melissococcus plutonius. The fungus Ascospheara apis did not occur in any of the samples.
|
|
|
Paenibacillus larave destroying the honeybees (Apis mellifera) population
Haltufová, Kristýna ; Hubert, Jan (advisor) ; Kamler, Martin (referee)
Paenibacillus larvae is Gram-positive, spore-forming, rod-shaped bacteria. This pathogen threatens one of the most considerable worldwide pollinators - the honeybee (Apis mellifera). It is causative agent of bee disease called American foulbrood. Although it affects only bee larvae, preferably on the first day of its live, it is highly contagious and could quickly destroy whole bee colony. Adult bees are not susceptible to infection, however due to huge spores resilient of P. larvae, they perform the role of main disease vector. Also the careless beekeepers make it easier to spread. Bee diseases are enquired by state veterinary administration, because honeybee is classified as a livestock. If disease evolves to clinic phase, infected bees and hive with all tools must be burned. American foulbrood is one of the most deleterious bee diseases. This bachelor thesis discuss about problems of whole disease and it is focused on the interactions between bacteria Paenibacillus larvae, hymenoptera insect honeybee and human factor presented by beekeepers, state veterinary administration and corresponding laws. Key words: Paenibacillus larvae, American Foulbrood, entomopathogenic bacteria, Apis mellifera, honeybee
|
|
|
Honey bee (Apis mellifera) workers as transmitters and reservoirs of American foulbrood (Paenibacillus larvae)
Haltufová, Kristýna ; Hubert, Jan (advisor) ; Kamler, Martin (referee)
Paenibacillus larvae is a gram-positive spore-forming bacterium that affects and kills the larvae of the honey bee (Apis mellifera) and causes the American foulbrood disease. Adults bees do not become infected, but they transmit tenacious spores within the hive and between hives and can infect larvae while caring for them. It is not allowed by law to treat bees in the Czech Republic, but the recommended preventive method for reducing the amount of spores in the hive is the shook swarm method (bees are moved to a new clean hive and the old hive is destroyed with all brood and supplies). The aim of this work was to detect and quantify P. larvae in bee workers using the quantitative real-time polymerase chain reaction (qPCR). In the first experiment, the two set of samples were taken - bees before and after the shook swarm method, but the expected decrease in spores in the samples taken after shook swarm was not confirmed, and conversely, non-specific products were amplified. In the second experiment, the presence of P. larvae spores in samples from heavily infected hives (with clinical symptoms of American foulbrood) and from hives with almost no findings of P. larvae spores, both originating from the same habitat, were compared. In this case, the differences were clearly visible. There were not...
|
|
|
Genomic analysis of Paenibacillus larvae and its relation to virulence
Vlková, Kateřina ; Hrabák, Jaroslav (advisor) ; Fišer, Radovan (referee)
Paenibacillus larvae is a Gram-positive sporulating bacterium that causes American foulbrood (AFB). It is one of the most dangerous bacterial pathogens of the honeybee (Apis mellifera). P. larvae spores are highly infectious to bee larvae and resist physicochemical influences. P. larvae is subtyped using repPCR with ERIC primers (Enterobacterial Repetitive Integrance Consensus) into five genotypes (ERIC I-V), which possess different colony morphology, metabolism and especially virulence. There is a significant genetic variability among isolates of P. larvae, which may contribute to differences in virulence. P. larvae isolates used in this work were obtained from clinical cases of American foulbrood as well as from a debris collected from bee hives with no American foulbrood symptoms from all over the Czech Republic in cooperation with the Beekeeping Research Institute, s.r.o., Dol. The isolates were obtained from larvae and hive debris. Both virulet and avirulet strains were sequenced using the SMRT (single molecule real time) method on the Sequel platform (PacBio). This method is suitable for Whole Genome Sequencing (WGS), because it allows sequencing of long reads with high accuracy, eliminating the effect of a large number of repetitive sequences during the genome assembly. Furthermore,...
|
|
|
Paenibacillus larave destroying the honeybees (Apis mellifera) population
Haltufová, Kristýna ; Hubert, Jan (advisor) ; Kamler, Martin (referee)
Paenibacillus larvae is Gram-positive, spore-forming, rod-shaped bacteria. This pathogen threatens one of the most considerable worldwide pollinators - the honeybee (Apis mellifera). It is causative agent of bee disease called American foulbrood. Although it affects only bee larvae, preferably on the first day of its live, it is highly contagious and could quickly destroy whole bee colony. Adult bees are not susceptible to infection, however due to huge spores resilient of P. larvae, they perform the role of main disease vector. Also the careless beekeepers make it easier to spread. Bee diseases are enquired by state veterinary administration, because honeybee is classified as a livestock. If disease evolves to clinic phase, infected bees and hive with all tools must be burned. American foulbrood is one of the most deleterious bee diseases. This bachelor thesis discuss about problems of whole disease and it is focused on the interactions between bacteria Paenibacillus larvae, hymenoptera insect honeybee and human factor presented by beekeepers, state veterinary administration and corresponding laws. Key words: Paenibacillus larvae, American Foulbrood, entomopathogenic bacteria, Apis mellifera, honeybee
|
|
|
Vliv působení trávicího procesu zavíječe voskového (Galleria mellonella) na spory původce moru včelího plodu (Paenibacillus larvae).
MRÁZ, Petr
This diploma thesis deals with a serious honey bee (Apis mellifera) disease, the American foulbrood (AFB), and with possibilities of its control. The thesis is divided into two parts, the theoretical and the experimental. The theoretical part is written as a research and contains two big chapters. The first one describes American foulbrood disease and its causative agent, bacteria Paenibacillus larvae. The second part deals with the wax moth (Galleria mellonella). The experimental part then combines above mentioned themes in an effort to find the relationship between the wax moth caterpillars and bacteria P. larvae that could possibly help to control the AFB. The aim of this work was to determine whether the wax moth can disrupt resistant layers of P. larvae spores thanks to its well adapted digestive tract and whether it could change their germination.
|
|
|
Occurrence of bee brood plaque in South Bohemian region
ŠTURMOVÁ, Jana
In diploma thesis I dealt with American foulbrood infection. At first I was focusing on disease hazards of foulbrood and I was investigating the pathogenesis of the disease bacteria Paenibacillus larvae. Then I carried out analysis of slumgum by culture test in the laboratory. I watched the bacteria P. larvae under a microscope. Next, I followed outbreaks announced by Regional Veterinary Administration. I investigated procedures of the Regional Veterinary Administration in accordance with legislation and decree during detecting the disease of AFB on the habitats. At the end, I developed a list of proclaimed outbreaks in South Bohemia into graphs and chart for the period from 2006 to 2013. The only treatment against this disease so far is burning hives, including all equipment of apiary. That is why I pointed out the importance of reporting suspected outbreaks of American foulbrood, respecting the rules and precautions by beekeepers, and beekeepers should also breed only healthy and strong beehives. Only then the spread of American foulbrood can be prevented and the originator of American foulbrood, the P. larvae, which is very durable, can be suppressed.
|
guest ::
