Cobalt deficiency in New York State.

Abstract

Feeding trials with lambs have clearly shown that New York State contains areas that are deficient in cobalt. Lambs fed a low-cobalt ration developed a deficiency of this element in 4–7 months characterized by loss of appetite, loss of weight, a simple anemia and death. Cobalt salts given to cobalt-deficient lambs by mouth resulted in a return of appetite within about a week. This was quickly followed by increased weight gains. Hemoglobin levels started to rise sometime later, about six weeks. Cobalt salts injected into cobalt-deficient lambs were completely ineffective in altering the course of the deficiency. As compared to cobalt-fed lambs, cobalt-deficient lambs showed a slightly lower concentration of blood plasma proteins; a slightly lower blood plasma calcium concentration; a lower blood plasma alkaline phosphatase activity and about the same blood plasma inorganic phosphorus concentration. Autopsy and microscopic tissue studies showed that cobalt-deficient lambs had fatty degeneration of the livers and a marked hemosiderosis of the spleens.