Effects of Varying the Amounts of Dietary Calcium on Selenium Metabolism in Dairy Calves

Abstract

Influence of dietary Ca on Se metabolism was studied with 16 intact male Holstein calves averaging 86 kg. Calves were assigned randomly and fed one of four diets containing, .17, .67, 1.31, and 2.35% Ca at 3% of their body weight for 4 wk. The diets contained .062 ppm Se and .34% P. Four days prior to the end of the experiment, calves were dosed orally with radioactive 75Se. Dietary Ca had no significant effect on 75Se absorption. There was a slight curvilinear relationship between apparent 75Se absorption and dietary Ca intakes. Urinary excretion of 75Se and stable Se tended to decrease with increasing dietary Ca, but differences were not significant. No significant differences were found in concentration of 75Se in several tissues. Kidney and liver had the highest concentration with that in kidney being about four times that of liver. Apparent 75Se absorption was decreased 10 to 6%, respectively, in calves fed extremely low and high amounts of Ca, compared with those receiving the requirement (.67% Ca). These small reductions along with a small R2 suggest that dietary Ca probably is of little practical importance relative to Se metabolism in calves.

Effect of Varying Dietary Levels of Calcium and Phosphorus on Apparent Digestibility and Retention of Macro and Micro-Minerals in Lactating Sahiwal Cows

“…Care (1994) also reported that higher dietary Ca levels decreased Mg absorption in cows. Lower bioavailability of Mg in response to higher dietary Ca levels was also reported by Alfaro et al (1987). Verdaris and Evans (1976) reported Mg absorption and retention (percent of intake) was higher in Holstein cows fed on diets low in Ca (0.2% vs 2.1%).…”

“…While Ca may not have direct effect on Zn absorption, it can decrease Zn absorption in the presence of phytate (Oberleas et al, 1996). Other than Zn and Selenium, little information is available on effects of dietary Ca levels on other trace elements absorption in dairy cows (Harrison and Conrad;1984;Alfaro et al, 1987). At higher dietary Ca levels, a negative interaction with Zn absorption is possible.…”

Metabolism of selenite, selenomethionine and feed-incorporated selenium in lactating goats and dairy cows

“…However, neither Cu (Rahim et al 1986, Koenig et al 1989), Fe, Cd, Mo, Mn (Rahim et al 1986) nor Co (van Ryssen et al 1987) affected selenite absorption. Absorption of selenium may be decreased on low or high calcium intake (Alfaro et al 1987), with the optimal dietary calcium level being 8 g/kg DM for selenium absorption in the dairy cow (Harrison and…”

True absorption of selenium in dairy cows: Stable isotope tracer methodology and effect of dietary copper

“…Se from the analysis of liver was lower than that determined from the analysis of serum ( On the other hand, Alfaro et al (1987) reported that dietary Ca (0. l7 -2.35 %) had no effect on /)Se absorption in dairy calves. White et al (1981) reported no significant effect of supple- …”