Evidence for absorption of silicon and aluminum by hens fed sodium zeolite A.
The mechanism of action of zeolite A (ZA) on eggshell quality could be related either to its ion-exchange properties or to individual ZA elements (Al or Si). Two experiments were conducted to determine 1) whether any ZA passes through the digestive system in its original form; and 2) whether any Al and Si absorption occurs. In Experiment 1, unfed hens were intubated with either 0 or 5 g ZA at oviposition. In Experiment 2, fed and unfed hens were intubated at oviposition with 0, 1, or 2 g ZA. At the subsequent oviposition, liver and kidney tissues, excreta, urine, bile, and plasma were collected and analyzed for Al, Si, Na, K, and P. The results indicated that approximately 7% of the intubated ZA passed through the digestive system in its original form (Experiment 1). As the intubated level of ZA increased, excreta Al and Si (P < .0001), urine Si (P < .005), and urine Al (P < .07) also increased (Experiment 2). Aluminum recovery from excreta ranged from 75 to 93% of the quantity intubated in all treatments. Corresponding values of Si from excreta of unfed and fed hens ranged from 76 to 81% and 58 to 60%, respectively. The P content of excreta was not influenced by ZA. However, excreta P was greater (P < .0001) in unfed than in fed hens. Neither plasma electrolytes (Na, K, and P) nor Al or Si levels in either liver or kidney were influenced by ZA.(ABSTRACT TRUNCATED AT 250 WORDS)
Roland
D A
DA
Department of Poultry Science, Auburn University, Alabama 36849.
Rabon
H W
HW
Rao
K S
KS
Smith
R C
RC
Miller
J W
JW
Barnes
D G
DG
Laurent
S M
SM
D000535:Aluminum / Q000493:pharmacokinetics*; D000538:Aluminum Silicates; D000821:Animal Feed; D000818:Animals; D001646:Bile / Q000737:chemistry; D002645:Chickens / Q000378:metabolism*; D005243:Feces / Q000737:chemistry; D005260:Female; D007408:Intestinal Absorption; D007668:Kidney / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D010058:Oviposition; D012825:Silicon / Q000493:pharmacokinetics*; D014018:Tissue Distribution; D017641:Zeolites
D000538:Aluminum Silicates; D017641:Zeolites; D000535:Aluminum; D012825:Silicon