Insufficient nutrition of animals or an inadequate balance in their diet causes emaciation, death, anaemia, stress, and contributes to the severity of diseases such as mange.
The problem may occur as a result of drought or insufficient pastureland. It may be because of negligence or ignorance, or lack of financial means to provide adequate feeding. Alternatively, it may be deliberate, as with the production of white veal, where calves are deprived of all roughage and fed only on milk substitutes which induces anaemia. They suffer severe stress because of this, and may try to obtain fibre from the wooden crates in which they are housed.