Fungus Intracellular obligate parasites Infect many animals particularly

Fungus intracellular obligate parasites infect many

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- Fungus - Intracellular obligate parasites - Infect many animals particularly insects - Transmittedby spores - Not very resistant spores Nosemosis - Nosema apis and Nosema cerane - Spores remain viable on combs for many months - Have to extract DNA to tell the difference Disease development - infected bees defecate on combs - Young bees clean the comb and become infected Disease development 1. Spores reach ventriculus 2. Nosema germinates 3. Nosema enters the cell through the polar filament 4. Nosema multiplies 5. The cell explodes and releases spores Damage caused by Nosema apis - Decreased digestion and nutrient absorption - Lifespan may be shortened - Atrophy of hypopharingeal glands - Decreased laying ability of Queen - Slow population buildup in spring Nosema infection levels - High during spring (feces on combs are cleaned) - Low during summer (foraging conditions allow external defecation) - Long cold winter – more nosema - Mild winter – less nosema Nosema symptoms
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- No clear symptoms in most cases - Somewhat similar to tracheal mite symptom - Dysentery and spotting – they defecate outside the hive and leave fecal spots everywhere – on top of the bars of the hive frames – diarrheal symptoms Detection of Nosema spores through microscopy - Nosema spp DNA extraction and PCR reaction Length of the life of Nosema infected and uninfected bees - Nosema ceranae reduced the bees’ lifespan by 14% - Significant, but not a lot! Alternative Nosema control - Replace old comb (30% a year) - Disinfect comb with acetic acid (2 ml/L, 150 mL) Paralysis - Infectious disease of the adult honey bee caused by two viruses: the chronic and the acute paralysis viruses - The disease is characterized by trembling movements of the affected bees - Inbreeding and hereditary factors predispose disease development - Varroa and tracheal mites might transmit the viruses - Not considered a serious problem - Still a poorly understood condition Paralysis symptoms - Trembling with open wings - Bees crawl on the ground - Hairless black bee - Affected bees are attacked by other workers Diagnosis: Elisa test PCR Can treat by requeening – precautionary Other Viruses - Deformed wing virus - Kashmir bee virus - Black queen cell virus - All of them associated to mites: Varroa and tracheal mites Pests: Wax moth - Two moths – greater and smaller - Galleria melonella - Larvae feed on wax and pollen
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- Affect weak colonies and unprotected stored combs during the warmest months Wax moth cycle - Adults mate outside the hive and females return to lay eggs on combs - Larvae burrow tunnels in the midrib of combs (protected from worker bees) spinning silken threads - Galleria pupates on wooden frames and boxes - The cycle is completed in 1-6 months (dormancy in the prepupal stage) - Destroys the comb and bees abscond - Leave pupa shaped marks on the frames – ruins the equipment Wax moth control - Maintain strong and populous colonies - Store empty equipment at freezing temperatures during winter – takes care of all stages of the wax moth Wasps - Entrance reducers Ants -
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  • Fall '12
  • ErnestoGuzman
  • Beekeeping, Honey bee, bees, The Queen

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