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K. Wolf

Publications and source records attributed to K. Wolf.

114 records · Page 7Linked to original sources
USGS1959

Infectious nature of pancreatic necrosis

To determine if pancreatic necrosis is a communicable disease of trout, lots of eyed brook trout eggs were obtained from four hatcheries. Pancreatic necrosis appeared spontaneously in trout from one of these hatcheries and the other strains were exposed to infection by suspension prepared from diseased fish. In all cases, typical pancreatic necrosis appeared in fish exposed to infection and the control fish remained healthy. Disease was more acute in fry fed brine shrimp nauplii than in those fed beef liver. Mortality data suggest that susceptibility to pancreatic necrosis decreases with the increased age of trout. No treatment for the disease is known, but sanitary measures were effective in preventing its spread.

Transactions of the American Fisheries Society↗
USGS1956

Experimental induction of blue-sac disease

Blue‐sac disease, an abnormal condition of sac fry, has been recognized for nearly 90 years. At least 23 postulated causes have been advanced, but reports of consistently reproducible results have not been found in literature. Methods whereby blue‐sac disease was induced at will are described. Closed‐system incubation, whereby metabolic wastes accumulated, resulted in incidences of blue‐sac disease roughly proportional to the period of holding and to ammonia concentrations which developed. Blue‐sac disease was also induced by adding synthetic nitrogen compounds to water used for incubating eggs and fry.

Transactions of the American Fisheries Society↗