J. Anim Sci.
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

J. Anim Sci. 1986. 63:457-466.
© 1986 American Society of Animal Science
This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Reinhart, G. A.
Right arrow Articles by Mahan, D. C.
Right arrow Search for Related Content
PubMed
Right arrow Articles by Reinhart, G. A.
Right arrow Articles by Mahan, D. C.

Effect of Various Calcium:Phosphorus Ratios at Low and High Dietary Phosphorus for Starter, Grower and Finishing Swine1,2,

G. A. Reinhart and D. C. Mahan3

The Ohio State University,4, Wooster 44691

Abstract

Three 2 x 4 factorial randomized-block design experiments were conducted to evaluate the effects of various Ca:P ratios (1.3:1, 2.0:1, 3.0:1, 4.0:1) at two dietary P levels (.05% below NRC, .10% above NRC) on growth, serum mineral and bone measurement characteristics in starter, grower and finisher swine. Experimental diets were formulated using corn and soybean meal with total dietary Ca and P levels adjusted using limestone and dicalcium phosphate at the expense of cornstarch. Pigs fed low P diets displayed a trend toward lower daily gains and higher feed conversions after the Ca:P ratio exceeded 1.3:1, whereas when high dietary P was provided, adverse effects on performance were not observed until the Ca:P ratio exceeded 2.0:1. Serum Ca concentrations were higher (P<.01) and serum P lower (P<.01) with increasing Ca:P ratio, with the response more pronounced at low dietary P levels. Percent bone ash decreased as Ca:P ratio widened during the starter (P<.01) and grower (P<.01) production phases, with finisher-phase bone ash demonstrating a minimal response. Dietary P level had a greater effect on percent bone ash than Ca:P ratio, with high dietary P resulting in increased percent bone ash in the starter (P<.01), grower (P<.01) and finisher (P<.01) phases. Bone-bending moment and bone stress were higher at the high dietary P level in grower (P<.01) and finisher (P<.01) phases, whereas bone-bending moment and bone stress declined during grower (P<.05) and finisher (P<.05) phases, respectively, as Ca:P ratio widened. Bone wall thickness increased (P<.01), but inside bone diameter decreased (P<.05), with high dietary P. Wider Ca:P ratio resulted in decreased bone wall thickness in both grower (P<.01) and finisher swine (P<.10). These results suggest that high Ca:P ratios can adversely affect swine performance and bone development during each production phase. When low dietary P is provided, Ca:P ratios above 1.3:1 resulted in decreased growth and bone development, whereas when high dietary P levels are provided, detrimental effects were not exhibited until the Ca:P ratio exceeded 2.0:1.

Footnotes

1 Salaries and research support provided by State and Federal Funds appropriated to the Ohio Agr. Res. and Dev. Center, The Ohio State Univ. Journal Article No. 183-85.

2 Appreciation is expressed to R. Todd and B. Taylor for their help in collection of performance data.

3 Reprint requests: Anim. Sci. Dept., Ohio State Univ., Wooster.

4 Ohio Agr. Res. and Dev. Center






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1986 by the American Society of Animal Science.