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出典:『Wikipedia』 (2011/04/22 09:43 UTC 版)

英語による解説

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Ascaridia (pronounced /æskəˈrɪdiə/) is the name of a genus of parasitic nematodes. Members of the genus are primarily intestinal parasites of birds. There are three well known species, namely, A. galli found mostly in chicken, A. dissimilis in turkeys, and A. columbae in pigeons. Lesser known species such as A. hermaphrodita, A. sergiomeirai, A. ornata, A. nicobarensis and A. platyceri are found in parrots. Among these A. galli is the most important and most pathogenic species, responsible for 'ascaridiasis' of poultry. Symptoms of heavy infection include diarrhea, stunted growth, listlessness and enteritis. The eggs of these nematodes are characterized by a thick shell, smooth and ellipsoidal, and composed of three distinct layers. They exhibit direct life cycle involving release of eggs into the soil and then ingesting them subsequently along the food. Eggs are resistant to desiccation, persist for a long time in the environment, and remain directly infective. Therefore control of infection involves the prevention of contamination of feeders and drinkers with faeces; pasture rotation and regular treatment, especially for young birds.