Influence of sodium aluminosilicate, hydroxy-sodalite, carnegieite, aluminum sulfate, and aluminum phosphate on performance of commercial Leghorns

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)

Effect of dietary sodium zeolite A on zinc utilization by chicks

Two experiments were conducted with chicks from 5 to 15 days posthatching to study the effect of sodium zeolite A (SZA) on Zn utilization. The corn-soybean meal basal diet was supplemented with ZnCO3 to provide three levels of dietary Zn (35, 40, and 85 ppm) in Experiment 1, and two levels of dietary Zn (85 and 4,000 ppm) in Experiment 2. Experimental diets also contained either 0 or .75% SZA, resulting in a 3 x 2 and a 2 x 2 factorial arrangement of treatments in Experiments 1 and 2, respectively. The tendency for increased growth, feed intake, and hematocrit in chicks fed Zn-supplemented diets in Experiment 1 suggests that the 35-ppm level of Zn in the basal diet was marginal for chicks. Both supplemental Zn and SZA increased (P < .02) hematocrit and plasma, pancreas, and tibia Zn and decreased (P < .02) tibia Cu. Sodium zeolite A increased (SZA by Zn, P < .03) tibia Al and tended to increase (SZA by Zn, P < .09) liver Fe in chicks fed either 35 or 85 ppm Zn, but SZA had no effect on tibia Al and liver Fe in chicks fed 40 ppm Zn. In Experiment 2, both SZA and excess dietary Zn decreased gain, feed intake, gain: feed, hematocrit, hemoglobin, and plasma alkaline phosphatase (AP) activity, and increased tibia, liver, and pancreas Zn, and tibia Al. In addition, excess Zn increased (P < .05) plasma Zn and liver Al but decreased (P < .01) plasma, liver, and pancreas Cu and percentage of tibia ash. The addition of SZA enhanced the adverse effects of excess Zn by further decreasing feed intake, hematocrit, hemoglobin, and plasma AP and Cu and by increasing tibia Al and liver Zn. Sodium zeolite A increased pancreas (P < .09) and tibia (P < .03) Zn regardless of dietary Zn concentration; however, SZA increased plasma Zn only in chicks fed 85 ppm Zn (SZA by Zn, P < .03). Sodium zeolite A tended to improve Zn utilization in chicks fed inadequate Zn but exacerbated the adverse effects of feeding excess Zn. The addition of SZA to the diet of chicks fed inadequate, adequate, or toxic levels of Zn resulted in increased tissue Zn concentration.