A Study of Vitamin B12 Deficiency in the Calf

Abstract

A series of calves maintained on a “synthetic milk” diet in which the protein source was alpha-protein from soybeans, supplemented with methionine, lard, cerelose, minerals, and vitamins other than vitamin B₁₂, exhibited a cessation of growth, poor appetite and, in some cases, incoordination. Examination of the peripheral nerves of some of these calves revealed varying degrees of demyelination, and the distribution of bone marrow cells showed a low proportion of the myeloid series. In some animals growth was resumed following liver extract or crystalline vitamin B₁₂ therapy, and a reticulocytosis was observed in the bone marrow. Other animals exhibited only transient responses to vitamin B₁₂ therapy, intramuscular or oral, and still others failed to show any response at all. Biliary obstruction was observed in four calves and was suspected in at least two others. The fact that good growth was previously induced in calves fed a diet differing only in that casein replaced alpha-protein plus methionine indicates that casein may have been supplying one or more factors in addition to vitamin B₁₂ which are required for the normal development of the calf. Copyright © . .