Influence of a wide range of calcium intakes on tissue distribution of macroelements and microelements in dairy calves.
Sixteen intact male Holstein calves averaging 86 kg and 63 d of age were assigned randomly to four treatment groups. The four treatment diets contained .17, .67, 1.31, and 2.35% Ca on an as-fed basis. The resulting Ca:P ratios with P held constant at about .34% were .47:1, 1.92:1, 3.83:1, and 7.20:1. Calves were fed diets at 3% of their body weights for 4 wk. Magnesium in the bone ash and serum was lowered by the 2.35% Ca treatment. Serum inorganic P was also reduced by the highest Ca diet during the last 2 wk of the experiment. Liver had the highest concentration of Zn in calves fed .67% Ca, and the muscle from calves fed 1.31% Ca diet had the lowest amount of Zn. Copper was reduced in pancreas for 1.31% Ca diet, but Ca was highest in the muscle and heart at the .67% Ca treatment. Weight gains and feed efficiencies were not affected by Ca. Fecal pH was different among treatments and increased as Ca intake increased. Young growing dairy calves can adapt to a wide range of Ca intakes and Ca:P ratios and maintain a moderate growth rate for 4 wk. It appears that excessive dietary Ca may affect concentrations of Zn, Fe, Cu, and Mn in some body tissues, but the magnitude of the effect is relatively small.
Alfaro
E
E
Department of Animal and Dairy Science, University of Georgia, Athens 30602.
Neathery
M W
MW
Miller
W J
WJ
Crowe
C T
CT
Gentry
R P
RP
Fielding
A S
AS
Pugh
D G
DG
Blackmon
D M
DM
D000818:Animals; D002118:Calcium / Q000097:blood / Q000493:pharmacokinetics*; D002136:Calcium, Dietary / Q000008:administration & dosage / Q000494:pharmacology*; D002417:Cattle / Q000378:metabolism*; D003300:Copper / Q000493:pharmacokinetics; D007501:Iron / Q000493:pharmacokinetics; D008274:Magnesium / Q000493:pharmacokinetics; D008297:Male; D008345:Manganese / Q000493:pharmacokinetics; D010758:Phosphorus / Q000097:blood / Q000493:pharmacokinetics*; D014018:Tissue Distribution / Q000187:drug effects; D014131:Trace Elements / Q000493:pharmacokinetics*; D015032:Zinc / Q000493:pharmacokinetics
D002136:Calcium, Dietary; D014131:Trace Elements; D010758:Phosphorus; D008345:Manganese; D003300:Copper; D007501:Iron; D008274:Magnesium; D015032:Zinc; D002118:Calcium