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{{Taxobox
 
{{Taxobox
|name               =''Ascaris suum''
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|name =''Ascaris suum''              
|kingdom           =Animalia
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|kingdom =Animalia            
|sub-kingdom       =
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|sub-kingdom =        
|phylum             =[[Nematodes|Nematoda]]
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|phylum =[[Nematodes|Nematoda]]            
|super-class       =
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|super-class =        
|class             =Chromadorea
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|class =Chromadorea              
|sub-class         =
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|sub-class =          
|super-order       =
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|super-order =        
|order             =Rhabditida
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|order =Rhabditida              
|sub-order         =Spirurina
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|sub-order =Spirurina          
|super-family       =[[Ascaridoidea]]
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|super-family =[[Ascaridoidea]]      
|family             =Ascarididae
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|family =Ascarididae            
|sub-family         =
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|sub-family =        
|genus             =Ascaris
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|genus =Ascaris              
|species           =''A. suum''
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|species =''A. suum''            
 
}}
 
}}
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{| cellpadding="10" cellspacing="0" border="1"  
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{| cellpadding="10" cellspacing="0" border="1"  
 
| Also known as:
 
| Also known as:
| '''''A. suum'',  
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| '''''A. suum'',  
 
large pig roundworm
 
large pig roundworm
 
|-
 
|-
 
|}
 
|}
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[[Image:Ascaris suum egg.jpg|thumb|right|150px|''A. suum'' egg - RVC/FAO guide to veterinary parasitology]]
    
''Ascaris suum'' is a member of the Ascarididae family and is the major cause of [[ascariasis]] in pigs. Its life cycle, like all ascarids, is not typical of nematodes as the infectious stage is within the egg. Due to the migratory life cycle of the larval stages this parasite can be the cause of [[Pigmentation and Calcification - Pathology#Post-Hepatic (Obstructive) Icterus|post-hepatic jaundice]] and [[Respiratory Parasitic Infections - Pathology#Ascaris suum|pneumonia]]. The nematode may also be a reservoir of [[Swine Influenza|Swine influenza]]. The major detremental effects of ''A. suum'' is in the economic loss due to the damage to liver tissue, white spot, and the decreased growth rate of the pigs. Up to 7% of pig liver in the UK is trimmed or condemned at slaughter due to the presence of white spot due to ''A. suum'' infection.
 
''Ascaris suum'' is a member of the Ascarididae family and is the major cause of [[ascariasis]] in pigs. Its life cycle, like all ascarids, is not typical of nematodes as the infectious stage is within the egg. Due to the migratory life cycle of the larval stages this parasite can be the cause of [[Pigmentation and Calcification - Pathology#Post-Hepatic (Obstructive) Icterus|post-hepatic jaundice]] and [[Respiratory Parasitic Infections - Pathology#Ascaris suum|pneumonia]]. The nematode may also be a reservoir of [[Swine Influenza|Swine influenza]]. The major detremental effects of ''A. suum'' is in the economic loss due to the damage to liver tissue, white spot, and the decreased growth rate of the pigs. Up to 7% of pig liver in the UK is trimmed or condemned at slaughter due to the presence of white spot due to ''A. suum'' infection.
    
===Indentification===
 
===Indentification===
''Ascaris suum'' is a large roundworm of pigs, each worm can grow up to 40cm long. As with all nematodes the females are considerably larger than the males.  
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''Ascaris suum'' is a large roundworm of pigs, each worm can grow up to 40cm long. As with all nematodes the females are considerably larger than the males.  
    
=== Life-Cycle ===
 
=== Life-Cycle ===
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=== Epidemiology ===
 
=== Epidemiology ===
''A. suum'' is seen globally, however in temperate regions infection normally occurs in the summer months due to the warmer temperatures. Young piglets up to about 6 months old are most susceptible although they begin to develop immunity at about 4 months. Sows carrying adult worms will contaminate the farrowing house rapidly, as female worms can produce 200,000 eggs per day, causing a high incidence of infection in the litter. The highly resistant eggs can survive in the environment for up to 4 years with suitable conditions, this makes control very difficult especially in free range systems.  
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''A. suum'' is seen globally, however in temperate regions infection normally occurs in the summer months due to the warmer temperatures. Young piglets up to about 6 months old are most susceptible although they begin to develop immunity at about 4 months. Sows carrying adult worms will contaminate the farrowing house rapidly, as female worms can produce 200,000 eggs per day, causing a high incidence of infection in the litter. The highly resistant eggs can survive in the environment for up to 4 years with suitable conditions, this makes control very difficult especially in free range systems.  
    
===Immunity===
 
===Immunity===
Young piglets are most susceptible to infection, in older animals immunity does develop but can take a few months to become strongly protective. Even 'immune' animals can carry small numbers of adult worms and therefore contaminate the environemnt.  
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Young piglets are most susceptible to infection, in older animals immunity does develop but can take a few months to become strongly protective. Even 'immune' animals can carry small numbers of adult worms and therefore contaminate the environemnt.  
    
===In Cows===
 
===In Cows===
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