About Us | Help Videos | Contact Us | Subscriptions
 

Abstract

 

This article in JEQ

  1. Vol. 32 No. 4, p. 1481-1489
     
    Received: Mar 13, 2002


    * Corresponding author(s): bjoern@purdue.edu
 View
 Download
 Alerts
 Permissions
Request Permissions
 Share

doi:10.2134/jeq2003.1481

Phytase, High-Available-Phosphorus Corn, and Storage Effects on Phosphorus Levels in Pig Excreta

  1. Christopher A. Baxtera,
  2. Brad C. Joern *a,
  3. Darryl Raglanda,
  4. Jason S. Sandsb and
  5. Olayiwola Adeolab
  1. a Dep. of Veterinary Clinical Science, Purdue Univ., West Lafayette, IN 47907
    b Dep. of Animal Science, Purdue Univ., West Lafayette, IN 47907

Abstract

Phosphorus-based land application limits for manure have increased the importance of optimizing diet P management and accurately characterizing the bioavailability of manure P. We examined the effects of pig (Sus scrofa) diets formulated with high-available-P corn and phytase on P levels in excreta and slurry stored for 30, 60, 90, 120, and 150 d. Twenty-four pigs (approximately 14 kg each) were fed one of four low-P diets: (i) normal corn, no phytase (control); (ii) normal corn with 600 phytase units kg−1 (PHY); (iii) high-available-P corn, no phytase (HAP); and (iv) high-available-P corn with 600 phytase units kg−1 (HAP + PHY). Fresh fecal and stored slurry dry matter (DM) was analyzed for total phosphorus (TP), dissolved molybdate-reactive phosphorus (DRP), dissolved organic phosphorus (DOP), acid-soluble reactive phosphorus (ASRP), acid-soluble organic phosphorus (ASOP), and phytate phosphorus (PAP). The PHY, HAP, and HAP + PHY diets significantly (α = 0.05) decreased fecal TP 19, 17, and 40%, respectively, compared with the control. Dissolved reactive P was 36% lower in the HAP + PHY diet compared with the other diets. Relative fractions (percent of TP) of DRP, DOP, ASOP, and PAP in slurry generally decreased with storage time up to 150 d, with the largest decreases occurring within 60 to 90 d. Diet-induced differences in relative fractions of DRP, DOP, ASRP, and PAP were significant when averaged across storage times, simulating a mixed-age slurry. Relative fractions of DRP in simulated mixed-age slurries were higher in HAP and HAP + PHY diets, indicating that diet may affect P losses under certain P-based application scenarios.

  Please view the pdf by using the Full Text (PDF) link under 'View' to the left.

Copyright © 2003. American Society of Agronomy, Crop Science Society of America, Soil Science SocietyPublished in J. Environ. Qual.32:1481–1489.