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第15号公告板 - Summer 2003
Parasitology- No Category
DE BIE S.
A. suum incidence.
Pig Progress, June 2003: 14-15
Ascaris suum infection is common in many European countries. In a recent survey, white spots were found at rates of 4.3% to more than 50% of livers from slaughter pigs. In a single herd, the rate of infection can vary from batch to batch, due to the epidemiology of the parasite. Liver spots reflect the number of larvae present in the pig during the five weeks prior to examination. Embryonated eggs ingested by the pig hatch and migrate out of the small intestine within 24 to 48 hours. They then migrate to the liver and then to the lungs. About 2 weeks after ingestion, the worms arrive in the intestine, where they complete their development. Economic losses, estimated at about 3.5 euros per slaughtered pig, are caused by the direct damage to the liver and lungs, by the slower growth rate that ensues, and the condemnation of livers.
