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Animal Husbandry Department

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wahlstrom, parakeratosis, swine nutritional diseases


A skin disease of swine called parakeratosis has become increasingly prevalent in South Dakota and throughout the United States during the past few years. Minnesota investigators first described parakeratosis in 1953 and suggested that it was of nutritional origin. Recent research at several experiment stations has shown that high levels of calcium and phosphorus in the ration were associated with the disease and that the addition of zinc had a curative effect. Swine affected by parakeratosis have reduced appetite, fail to grow normally, and often exhibit diarrhea during the early stages of the disease. The skin lesions appear almost simultaneously with these early symptoms. The condition is first noted by the reddening of the skin on the underline followed by poxlike lesions on the abdomen and between the front and rear flanks. Within a short time the crusty scablike lesions develop on the legs, ears, tail, and, in severe cases, cover the entire body. This often causes the skin to form large folds or wrinkles. There are great individual differences in the severity of the symptoms and duration of the disease. On the same rations, some animals may not show any symptoms of the disease while others show mild or severe symptoms. Death losses are quite low but there is often an economic loss due to poor growth and poor feed efficiency. Parakeratosis has occurred at the South Dakota Experiment Station at different times during the past few years. The condition has appeared most frequently in rations supplemented by plant proteins. It has been most prevalent from weaning age to 100 pounds during fall and winter feeding trials. When these trials were conducted it had not been observed at this station in pigs fed cereal grain and protein supplement free-choice. The following experiment was designed to study the occurrence of parakeratosis on different type rations and to study the effect of calcium and zinc on the development of this disease.










South Dakota State State College of Agriculture and Mechanic Arts, Agricultural Experiment Station