Cobalt deficiency in cattle and its impact on production

ABSTRACT: Two outbreaks of cobalt deficiency in beef cattle were diagnosed in Midwestern Brazil. We discuss the clinical, epidemiological, pathological features, therapeutic measures, and impact aspects of the production system associated with these outbreaks occurring outbreaks in two farms of extensive cattle raising-system in the state of Mato Grosso do Sul. Seven affected cattle were euthanized and necropsied. Tissues for histopathology and microelements dosage were secured. At Farm A, 3100 cattle of all ages got sick, and 396 died; at Farm B, 148 were affected, and 110 died. In both farms, cattle were fed the same mineral supplement. The main clinical signs were weight loss and weakness, even though a good supply of forage was available in the paddocks. Many cattle stop grazing and chew at tree barks, wood chips from fence posts, and bones. In addition to the deaths, there was a compromised growth, and the reproductive rates fell sharply. The necropsied cattle were thin, with rough hair coat and pale mucous membranes. The liver was diffusely orange and showed a lobular pattern. The bone marrow was gelatinous and diffusely yellow. Histological changes included hemosiderosis in the liver and spleen, hepatocellular vacuolar degeneration, and myeloid and erythroid hypoplasia of the bone marrow. In the white matter of four cattle’s brains, the myelin sheath was markedly distended (spongy degeneration). Proliferative parasitic abomasitis was observed in three cattle. The presumptive diagnosis was based on the association of the clinical picture, the necropsy findings, and the ruling out of other possible causes. The diagnosis was confirmed by the favorable response to treatment with cobalt and vitamin B12 orally and by mineral supplementation.

Relationship between Vitamin B12 and Cobalt Metabolism in Domestic Ruminant: An Update

Cobalt, as a trace element, is essential for rumen microorganisms for the formation of vitamin B12. In the metabolism of mammals, vitamin B12 is an essential part of two enzymatic systems involved in multiple metabolic reactions, such as in the metabolism of carbohydrates, lipids, some amino acids and DNA. Adenosylcobalamin and methylcobalamin are coenzymes of methylmalonyl coenzyme A (CoA) mutase and methionine synthetase and are essential for obtaining energy through ruminal metabolism. Signs of cobalt deficiency range from hyporexia, reduced growth and weight loss to liver steatosis, anemia, impaired immune function, impaired reproductive function and even death. Cobalt status in ruminant animals can be assessed by direct measurement of blood or tissue concentrations of cobalt or vitamin B12, as well as the level of methylmalonic acid, homocysteine or transcobalamin in blood; methylmalonic acid in urine; some variables hematological; food consumption or growth of animals. In general, it is assumed that the requirement for cobalt (Co) is expressed around 0.11 ppm (mg/kg) in the dry matter (DM) diet; current recommendations seem to advise increasing Co supplementation and placing it around 0.20 mg Co/kg DM. Although there is no unanimous criterion about milk production, fattening or reproductive rates in response to increased supplementation with Co, in some investigations, when the total Co of the diet was approximately 1 to 1.3 ppm (mg/kg), maximum responses were observed in the milk production.

Effect of cobalt supplementation on lamb growth rates in the face of cobalt deficiency

A hill farm in eastern Scotland had noted poor lamb growth rates since 2014. Cobalt, selenium and copper deficiencies were reported from historical blood sample results, and trace element supplementation had been administered to the ewes, but not the lambs. A supplementation trial was undertaken in 2018 to compare the daily liveweight gain (DLWG) between lambs supplemented with trace elements and unsupplemented lambs. The trace element supplements used were intraruminal boluses containing 51-mg cobalt, 10-mg selenium and 60-mg iodine (Downland Essential Lamb bolus, Downland). Blood samples taken two months postsupplementation showed that unsupplemented lambs had cobalt-deficient status, but not selenium deficiency. Lambs supplemented with the trace element boluses had an increase in DLWG of 49 g/day compared with unsupplemented lambs. This case confirms that cobalt supplementation on deficient farms can be associated with a significant improvement in growth rates of growing lambs on Scottish hill farms.

ESSENTIAL TRACE AND ULTRA TRACE ELEMENTS IN NUTRITION OF VEGETARIANS AND VEGANS. PART 2. IODINE, SELENIUM, CHROMIUM, MOLYBDENUM, COBALT

In addition to the inhibitory effect of phytic and oxalic acids, other factors also affect the provision of vegans and vegetarians with essential elements. Selenium comes predominantly from plant products. However, its content in plants depends on the concentration in soils, which varies considerably in different regions. The source of iodine is seafood. Studies show that all food groups are at high risk of iodine deficiency, but vegans and vegetarians are at greater. In addition, remoteness from the seacoast and the properties of agricultural soils also play a role in the status of iodine in the body. Currently, many countries are taking steps to prevent iodine deficiency (food fortification). Cobalt is part of vitamin B12, an essential micronutrient deficient in vegans and often even in vegetarians. In addition, cobalt is also a cofactor of other molecules. However, to date, data on the prevalence of cobalt deficiency is not enough for analysis. There is not enough information about the prevalence of molybdenum deficiency.

Fabrication of Nanostructured Gradient Tungsten-Cobalt Alloy Using Carbon Deficiency Powder

A nanostructured functionally graded hard alloy was obtained by sintering at temperatures from 1350 to 1410 ° C of two-layer "green bodies", each consisting of layer of powder with normal carbon content (WC-15Co-0.4VC-0.4Cr2C3) and powder layer with deficit of carbon (WC-8Co-0.4VC-0.4Cr2C3). The formation of the η phase (Co3W3C) in the layer with cobalt deficiency causes the migration of cobalt to it and prevents the return of cobalt back in a wide temperature range of temperatures (1350-1410). The porosity of the resulting nanocrystalline hard alloy at 1410 ° C is reduced to 2%, and the maximum hardness of the surface layer with a low cobalt content (10%) reaches 1945HV.

Trace Elements Have Beneficial, as Well as Detrimental Effects on Bone Homeostasis

The protective role of nutrition factors such as calcium, vitamin D and vitamin K for the integrity of the skeleton is well understood. In addition, integrity of the skeleton is positively influenced by certain trace elements (e.g. zinc, copper, manganese, magnesium, iron, selenium, boron and fluoride) and negatively by others (lead, cadmium, cobalt). Deficiency or excess of these elements influence bone mass and bone quality in adulthood as well as in childhood and adolescence. However, some protective elements may become toxic under certain conditions, depending on dosage (serum concentration), duration of treatment and interactions among individual elements. We review the beneficial and toxic effects of key elements on bone homeostasis.

Synthesis, Single Crystal Growth, and Properties of Cobalt Deficient Double Perovskite EuBaCo2−xO6−δ (x = 0–0.1)

The cobalt deficient double perovskites EuBaCo2−xO6−δ with x=0–0.1 were obtained both as powders and as single crystal. Formation of cobalt vacancies in their crystal lattice was shown to be accompanied by the formation of oxygen ones. Chemical lattice strain caused by this cooperative disordering of cobalt and oxygen sublattices was found to be isotropic contrary to that caused by the formation of oxygen vacancies only. Cobalt deficiency was also shown to lead to lowering overall conductivity and Seebeck coefficient of EuBaCo2−xO6−δ double perovskites as a result of simultaneous decrease of charge carriers’ concentration and their mobility as well as number of sites available for electrons and holes transfer. Strong anisotropy of the overall conductivity of the single crystal double perovskites EuBaCo2−xO6−δ was found and explained on the basis of preferential location of oxygen vacancies in the rare-earth-oxygen- (REO-) planes.