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'''Immunity'''
 
'''Immunity'''
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*Different ''Eimeria'' species produce different levels of protective immunity
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**''E.maxima'' -> ''E.brunetti'' and ''E.acervulina'' -> ''E.tenella'' and ''E.necatrix''
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*There is no cross immunity between species
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*There is very little passive immunity
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*Evokes a cell-mediated response
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*All ages of poultry are susceptible
    
'''Epidemiology'''
 
'''Epidemiology'''
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*Oocysts are ubiquitous and robust
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**Able to survive several months to years
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*It is impossible to keep buildings free from infection
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**Chicks become infected by pecking the ground shortly after being placed in the poultry house
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*Biotic potential is enormous
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**Generation time is short
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**Massive infections can build up rapidly
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*Immunity develops relatively slowly
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**With high stocking densities the situation is explosive
    
'''Control'''
 
'''Control'''
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