A number of nutritional disorders may be observed if local products are fed improperly. Chastek Paralysis can result from feeding certain types of fresh fish. This dietary disease was first recognized in 1932 on the Chastek Fur Farm in Minnesota. This disease can also be seen in mink and cats. It occurs because the enzyme thiaminase is in some fish and this destroys vitamin B1.
Foxes become weak, lose appetite and go into fits.
Cod should be cleaned since problem fish may be contained in the gut. Consumption of rancid feed can cause a Vitamin E deficiency . This can cause sudden death in mink kits and has also been described in fox. Less severe cases with staggering and hind quarter problems can be treated with intramuscular injections of Vitamin E. To avoid this problem, do not use rancid seal or any feed product that even appears rancid for furbearers diet. Biotin is a nutrient essential for normal growth.