Influence of high dietary aluminum on performance and phosphorus bioavailability in dairy calves.
Sixteen male intact Holstein calves averaging 72 kg and 64 d of age were used to study the effects of high dietary Al on calf performance and P bioavailability. The main effects were two concentrations of added aluminum (0 and .20% Al) and two of added P (0 and .22% P). The basal diet contained, by analysis, .132% P, .74% Ca, and .021% Al. The calves were assigned to four treatment groups balanced according to body weight. The four treatments were 1) normal P, low Al; 2) low P, low Al; 3) low P, high Al; and 4) normal P, high Al. Calved had ad libitum access to their respective diets for 7 wk. Metabolism of a single oral 32P dose was determined during wk 6. The adverse effects of high dietary Al include a 17% reduction in feed intake and a 47% reduction in body weight gains. Alkaline phosphatase and plasma glutamic oxaloacetate transaminase activities increased in calves receiving the high Al diets. A negative balance of P and Ca was noted in the calves fed high concentrations of Al. Apparent absorption of 32P was reduced (37%) in calved fed diets high in Al (44% of dose vs. 69%). Urinary excretion of 32P was not affected by dietary Al concentrations. Calves fed the low P (deficient) diet showed significant reductions in feed intake, weight gain, serum inorganic P, bone ash, and P content of bone. Dietary P did not significantly affect 32P absorption. Adding .20% dietary Al severely affects P metabolism and performance of young growing calves.
Crowe
N A
NA
Department of Animal and Dairy Science, University of Georgia, Athens 30602.
Neathery
M W
MW
Miller
W J
WJ
Muse
L A
LA
Crowe
C T
CT
Varnadoe
J L
JL
Blackmon
D M
DM
D000535:Aluminum / Q000008:administration & dosage* / Q000009:adverse effects; D000077410:Aluminum Chloride; D017607:Aluminum Compounds; D000821:Animal Feed; D000818:Animals; D001682:Biological Availability; D002118:Calcium / Q000378:metabolism; D002417:Cattle / Q000502:physiology*; D002712:Chlorides / Q000008:administration & dosage; D004063:Digestion / Q000187:drug effects; D004435:Eating / Q000187:drug effects; D008297:Male; D010758:Phosphorus / Q000493:pharmacokinetics*; D015430:Weight Gain / Q000187:drug effects
D017607:Aluminum Compounds; D002712:Chlorides; D010758:Phosphorus; D000077410:Aluminum Chloride; D000535:Aluminum; D002118:Calcium