Date of Award


Document Type


Degree Name

Doctor of Philosophy (PhD)


Animal Science (Animal, Dairy, and Poultry Sciences)

First Advisor

L. Lee Southern


Four experiments were conducted to investigate the effects of sodium zeolite A (SZA) on calcium (Ca), phosphorus (P), and zinc (Zn) utilization in broiler chickens from 5 to 14 or 15 days of age. In Experiment 1, two levels each of SZA (0 and.75%) and (or) Ca (1.0 and 1.5%) were fed to both uninfected and Eimeria acervulina-infected chicks. Excess dietary Ca reduced (P $$.10) in infected chicks (Ca x coccidiosis, P $<$.05). Addition of SZA to diets with excess Ca further decreased (P $<$.05) gain and tibia ash. These results suggest that SZA may exacerbate the adverse effects of excess dietary Ca. In Experiment 2, four levels of dietary Ca (.6,.8, 1.0, and 1.2%) and (or) two levels of SZA (0 and.75%) were fed. Sodium zeolite A decreased (P $<$.05) plasma P and tibia magnesium (Mg) but increased (P $<$.05) tibia Ca, Zn, aluminum (Al), and manganese (Mn). Tibia ash and shearing force were increased in chicks fed SZA and inadequate dietary Ca, but were decreased in chicks fed SZA and 1.2% Ca (Ca x SZA, P $<$.05). Dietary SZA enhanced tibia ash, density, and shearing force when dietary Ca was low; however, SZA reduced many bone mineralization indices in chicks fed excess Ca. In Experiment 3, various levels of dietary P (.41,.55, and.69%), Ca (.6 and 1%), and (or) SZA (0 and.75%) were fed. The addition of Ca, SZA, or both exacerbated the adverse effects of feeding low-P diets, yet alleviated the adverse effects of feeding low-Ca, high-P diets. Dietary SZA reduced (P $<$.01) plasma P and increased (P $<$.02) tibia Mn, Zn, copper (Cu), and Al. The SZA-induced increase in tibia Al was most evident in chicks fed low levels of P (SZA x P, P $<$.02). These data demonstrate that the effects of SZA are influenced by dietary concentrations of Ca and P, and that the addition of SZA to diets low in P results in bone Al accumulation. In Experiment 4, the effects of SZA on chicks fed inadequate (35 ppm), marginal (40 ppm), adequate (85 ppm), and excess (4,000 ppm) levels of Zn were assessed. Sodium zeolite A increased (P $<$.05) tibia and pancreas Zn regardless of dietary Zn concentration. Dietary SZA tended to alleviate the adverse effects of feeding inadequate Zn and exacerbate the adverse effects of feeding excess Zn.