vitamin E/ Selenium deficiency

• yellow fat disease where there was pale skeletal and cardiac muscle in animals fed fish or fish products, and it was thought that these rations were deficient in vitamin E.
• • Enzootic Nutritional Muscular Dystrophy (young, rapidly growing calves, lambs, kid & foals)
• • Antioxidant that prevents oxidative damage to sensitive membrane lipids by decreasing hydroperoxide formation
• Vitamin E and selenium are major antioxidants, and defi­ ciency may lead to a generalized myopathy in skeletal muscle but more likely manifests as mulberry heart disease or hepatosis dietetica.
• Previous disease names include microangiopa­ thy and white muscle disease.
• Affected animals are typi­ cally 3–7weeks of age and found dead with transmural myocardial hemorrhage, gelatinous pericardial material, and pulmonary edema
• There does not appear to be sex, breed, time of year, or known viral infection associated with the process
• Disease can occur when diets are con­ structed from plants that are grown in selenium‐deficient soils or soils containing selenium antagonists
• It may occur with increased frequency with ingestion of plants high in inhibitors of vitamin E, diets high in polyunsaturated fatty acids or copper, low vitamin A, or possibly mycotoxins that can destroy vitamin E or make it less available.
• Swine appear to be less susceptible to nutritional mus­cular dystrophy in skeletal muscle than other domestic species
• If it does occur, it is seen as pallor in the skeletal muscles with white streaks (gritty, calcified myofibrils, and muscle bundles) particularly in the longissimus dorsi.
• It is usually in pigs of 50–60 kg and clinically presented as ataxia, stiff gait, staggering gait, weakness, paralysis, depression, anorexia, and recumbency prior to death
• Chronic cases have lameness and shedding of hooves.
• Grossly, the muscle is edematous with white streaks, and histologically there is loss of myocyte structure with vacuolation, fragmentation, and mineral deposition in individual fibers
• The primary change is selective destruction of type I fibers and lack of phosphorylase activity in type II fiber
• Lowest conc VE in piglets: Day 45 after farrowing
• Dangerously low conc VE in piglets: First 3 to 4 weeks

  following the move to the finishing
• mixtures of soybean, high-moisture corn & cereal grains

  grown on soils with low levels of Se
• Diets containing linseed oil - reduced the VE levels in

  the diet but increased the skatole levels
• Presence of oxidized fat → reduces the resistance of the

  RBCs against peroxidation
• VE Prevents fatty acid hydroperoxide formation
• Uncoordinated, staggering gait (suggestive of muscular dystrophy)
• MHD - Liver - enlarged, appears mottled, and has a

  characteristic nutmeg appearance on the cut surface
• MHD - Peritoneal cavity - fibrin is often in the form of a

  lacy net covering all the viscera