Chromium and protein supplements for growing-finishing beef steers fed barley-based diets

Micronutrients and immune function in cattle

“…The incidence of respiratory disease is frequently high in stressed calves. Cr supplementation of stressed calves has reduced morbidity following transportation in some studies (Moonsie-Shageer & Mowat, 1993;Mowat et al 1993;Lindell et al 1994), but not in other studies (Chang & Mowat, 1992;Chang et al 1995;Mathison & Engstrom, 1995). Supplementing dairy cows with a Cr-amino acid chelate did not affect mammary gland health status (Chang et al 1996).…”

Relevance of National Research Council feed composition tables in Alberta

“…The P, Mn, S, Mg, CP, Se and Ca concentrations were 17, 18, 18, 22, 32, 50% and 100% higher than NRC values (Table 1). However, the concentrations of Cu and Zn in barley hay were quite low, being only 18 and 40% of the values reported by NRC (1984 and1989). Fifty-seven percent of the barley hay samples were below the average value for Zn (Table 5), and only 9% of the samples were above the upper requirement value of 50 mg kg -1 as suggested by NRC (1984).…”

“…The reasons for these differences, while not readily clear, may be partly related to soil types. In Alberta, for example, Cu deficiency has been reported on mineral soils in the Black, Gray-Black and Dark Brown soil zones (Penny et al 1991;Solberg et al 1994). As well, other factors such as, geographic location and environment, crop varieties, soil fertility and processing methods have been cited to explain the variation that exists in plant mineral concentrations (Berger 1995).…”

“…Similar factors could explain the rather high concentrations of Zn in barley grown in Alberta. The effects of low levels of Cu in barley grain cultivated in Alberta where cattle feedlots commonly feed diets of barley silage and barley grain (Mathison and Engstrom 1995) could mean that supplementation of this trace element is necessary in diets in which barley grain was a significant dietary component. The same can apply to high producing dairy cows where the Cu requirement in actual amounts is high.…”

“…The nutrient concentrations of selected Alberta-grown whole barley grain (Hordeum vulgare L.), three pure hays of alfalfa (Medicago sativa L.), barley, oat (Avea sativa L.), and four pure crop silages of alfalfa, barley, corn (Zea mays L.), and oat were determined and compared with nutrient concentrations of similar forages and a cereal grain reported in the National Research Council (NRC 1984 and1989) feed nutrient composition tables. In addition, the variations in nutrient concentrations within the selected Alberta feedstuffs were assessed as an indication of whether the feedstuffs should be analysed frequently for certain nutrients.…”