Molybdenum, Silver, Thallium and Vanadium

It is widely accepted that ratios of dietary copper (Cu) to molybdenum (Mo) lower than 10:1 may produce molybdenosis in cattle, especially if sulfur concentrations are more than 3,000 ppm. Some authorities suggest that dietary Mo concentrations greater than 10 ppm are hazardous to cattle regardless of Cu concentration, but anecdotal reports suggest that this may not be the case. The original purpose of the experiment described in this report was to investigate whether supranutritional supplemental Cu could protect cattle against relatively high dietary Mo. Pregnant cows were grazed on 1 of 3 pastures: 1 with only background Mo, 1 with an average of 13 ppm Mo, and 1 that averaged 230 ppm Mo. Half the cows on the Mo pastures were supplemented with 17 ppm dietary Cu, the other half with the dietary supplement plus Cu boluses. Molybdenum effects were anticipated in the groups supplemented with 17 ppm Cu; however, despite increased tissue concentrations of Mo, only the 230 ppm Mo/17 ppm Cu group exhibited any effects. Moderate Cu supplementation permitted cows to graze a site heavily contaminated with Mo with no adverse effects on general health or reproduction.

https://journals.sagepub.com/doi/pdf/10.1177/104063870601800607

Modest Copper Supplementation Blocks Molybdenosis in Cattle

Gardner, W. C., Naeth, M. A., Broersma, K., Chanasyk, D. S. and Jobson, A. M. 2012. Influence of biosolids and fertilizer amendments on element concentrations and revegetation of copper mine tailings. Can. J. Soil Sci. 92: 89–102. A 3-yr field study on copper mine tailings in British Columbia determined the effects of fertilizer and biosolids on element concentrations in tailings and vegetation and on plant biomass. Biosolids applied at 50, 100, 150, 200 and 250 Mg ha−1 (dry weight) increased total carbon, iron, magnesium, nickel, nitrogen, phosphorus, sulphur and zinc and available ammonium, iron, manganese, nitrate, phosphorus and zinc in tailings. With highest applications on silt loam tailings, total zinc (214 mg kg−1) exceeded Canadian Council of Ministers of the Environment guidelines for agricultural soils. Total chromium and copper exceeded these guidelines but not due to biosolids, being high in controls (chromium 38, 8; copper 647, 1291 mg kg−1; silt loam and sandy sites, respectively). Plant ti...

https://bioone.org/journals/canadian-journal-of-soil-science/volume-92/issue-1/CJSS2011-005/Influence-of-biosolids-and-fertilizer-amendments-on-element-concentrations-and/10.1139/CJSS2011-005.pdf

Influence of biosolids and fertilizer amendments on element concentrations and revegetation of copper mine tailings

Revegetation and sustainable cattle grazing are major objectives in the reclamation of mine tailings at the Highland Valley Copper mine in British Columbia, Canada. A total of 84 cow-calf pairs grazed forage extremely high in molybdenum (Mo) for 11 weeks in the summer and fall for 3 consecutive years (1999–2001). The average stocking rate was 0.63 ha AUM−1. The animals' diet consisted primarily of alfalfa (Medicago sativa L.) and orchardgrass (Dactylis glomerata L.) containing 100–400 ppm Mo. Both cows and calves showed adequate daily gains of 0.78 kg head−1 day−1 and 1.33 kg head−1 day−1, respectively. Uptake of Mo was demonstrated by elevated levels of Mo in rumen contents and feces. Clinical signs of Mo toxicity were observed in less than half of the cows and in only a few calves. Clinical signs included a stiff shuffling gait, watery diarrhea, and a rough hair coat. Lameness, the primary sign, was resolved in all animals by the end of each trial. Diarrhea was also resolved by the end of the t...

/pdf/clinical-signs-in-cattle-grazing-high-molybdenum-forage-52h50m7inq.pdf

Clinical signs in cattle grazing high molybdenum forage

Mineral deficiencies in cattle, widespread in East Africa, impair optimal health and production and consequently place a great burden on the farmers' income. Therefore, detection of shortages and imbalances of specific minerals is essential. Our objective was to evaluate the mineral status of grazing cattle around the Gilgel Gibe catchment in Ethiopia and associated factors. In study I, individual animal plasma and herd faecal Ca, P, Mg, Na, K, S, Fe, Zn, Mn and Cu concentrations were determined in adult zebu cattle (Bos indicus; n = 90) grazing at three altitudes around the catchment, whilst recording body condition score and sex. In study II, liver samples of adult male zebu cattle (n = 53) were analysed for Cu, Zn, Fe, Se and Mo concentrations and inspected for parasitic infections. Plasma and liver analyses revealed a Cu deficiency problem in the area, since 68 and 47 % of cattle, respectively, were Cu deprived according to diagnostic criteria for Bos taurus cattle. High hepatic Mo concentrations in 17 % of cases might reflect excessive dietary Mo intake. Liver Se and plasma Na concentrations were too low in 92 and 80 % of cattle. Plasma Mn concentrations were largely below the detection limit. Plasma Cu as well as Ca concentrations were lower in the lowest altitude compared to the highest altitude group (P < 0.05), whereas lean to medium cattle had lower plasma Cu concentrations (P < 0.05). No differences in hepatic mineral concentrations were detected between cattle with different types of parasitic infection. In conclusion, bovine mineral deficiencies were present in the Gilgel Gibe area and were associated with grazing altitude and body condition score.

Mineral deficiency status of ranging zebu (Bos indicus) cattle around the Gilgel Gibe catchment, Ethiopia

High concentrations (21–44 mg kg-1 dry matter) of Mo have been identified in forage in several reclaimed mining areas in British Columbia. Since Mo concentrations greater than 5 mg kg-1 in forage dry matter may result in molybdenosis because of a secondary Cu deficiency in ruminants, a study was undertaken to determine if cattle can safely graze the reclaimed land. For 12-wk grazing periods in 1994, 1995 and 1996, 32 cow/calf pairs grazed high-Mo forage at a reclaimed mine tailings site located at the Highland Valley Copper mine near Logan lake, BC. Half of the animals in the trial received a Cu supplement (All-Trace copper bolus) and the other half served as a control group. There were no significant differences (P < 0.05) in weight gain, liver Mo, serum Cu and Mo, and milk Cu and Mo between the two treatment groups of cows. Liver Cu was higher for the Cu bolus group at certain time periods in 1994 and 1995, indicating that the bolus was effective at supplying Cu. At all times, the liver Cu levels for th...

W. T. Buckley

Papers

Copper and health status of cattle grazing high-molybdenum forage from a reclaimed mine tailing site

The use of copper boli for cattle grazing high-molybdenum forage.