Occurrence: Worldwide.   Species affected: All.   Age affected: Young.

Causes: Deficiency of Vitamin E and/or selenium in the diet.

Effects: Weakness and signs of unthriftiness.

This disease is a vitamin E and/or selenium deficiency. All species of young birds are susceptible to this disease.

Deficiency in the diet.

Birds are weak and unthrifty signs occur.

Occurrence: Worldwide. Species affected: All. Age affected: Young.

Effects: Weakness and signs of unthiftiness.

This disease is a vitamin E and/or selenium deficiency. All species of young bird are susceptible to this disease.

Deficiency in the diet.

Birds are weak and unthrifty signs occur.

Light coloured streaks of easily distinguished affected bundles of muscle ...