Phytate has been shown to be an antinu-trient, and the feeding of high levels of phytase can break down phytate to improve nutrient utilization and pig performance. Dietary xylanase targets arabinoxylan breakdown, thereby improving energy utilization in pigs. However, the effects of simultaneous supplementation have not been clearly determined. Crossbred pigs (n = 45; mean initial weight, 26.4 ± 0.2 kg) were allotted to 1 of 9 treatments to evaluate the effects of both xylanase (endo-1,4-β xylanase [EC 126.96.36.199]) and phytase (6-phytase [EC 188.8.131.52]) supplementation as follows: 1) positive control (PC), a corn-soybean meal-based diet with 15% corn distillers dried grains with solubles, 15% wheat middlings, and 13% corn germ meal; 2) negative control (NC), ME was reduced by 103 kcal/kg from the PC diet by replacement of fat with corn starch; 3) NC + phytase (500 phytase units (FTU)/kg diet); 4) NC + phytase (1,000 FTU/kg diet); 5) NC + phytase (2,000 FTU/kg diet); 6) NC + xylanase (24,000 xylanase units [BXU]/kg diet); 7) NC + phytase (500 FTU/ kg diet) + xylanase (24,000 BXU/kg diet); 8) NC + phytase (1,000 FTU/kg diet) + xylanase (24,000 BXU/ kg diet); and 9) NC + phytase (2,000 FTU/kg diet) + xylanase (24,000 BXU/kg diet). All diets were formulated to meet nutrient requirements before phytase and xylanase addition to the diets. There were no significant interactions between xylanase and phytase supplementation on growth performance, carcass characteristics, and apparent total tract digestibility (ATTD). The ADG (P < 0.01, quadratic) and G:F (P < 0.05, linear) for the overall period increased as phytase level increased. The ATTD of P increased as phytase supplementation level increased (P < 0.05, linear and quadratic). The ATTD of DM, NDF, ether extract (P < 0.05), and hemicel-lulose (P = 0.05) increased quadratically as phytase level increased. Estimated carcass lean percentage and lean gain increased (P < 0.05, linear) as phytase level increased. Xylanase supplementation had no effect on growth performance, ATTD, and carcass characteristics. The results demonstrated an improved nutrient digestibility, performance, and carcass response to phytase supplementation beyond P provision because all diets exceeded current P requirement estimates based on standardized total tract digestible P.
|Number of pages||13|
|Journal||Journal of Animal Science|
|State||Published - Sep 2017|
Bibliographical noteFunding Information:
1This is publication number 16-07-062 of the Kentucky Agricultural Experiment Station and is published with the approval of the Director. This work is supported by the National Institute of Food and Agriculture, U.S. Department of Agriculture, multistate project number KY007087 under accession number 1002298. Partial funding for this project was provided by the National Pork Board, Des Moines, IA 50306. Appreciation is expressed to H. J. Monegue, I. F. Hung, N. Lu, J. Lim, J. Chang, and N. Inocencio for assistance in the care of pigs and laboratory analysis; D. Higginbotham for help in diet preparation; and Evonik Corporation (Kennesaw, GA) for ingredients used in the diets. 2Corresponding author: firstname.lastname@example.org Received May 31, 2017. Accepted June 28, 2017.
© 2017 American Society of Animal Science. All rights reserved.
- Apparent total tract digestibility
ASJC Scopus subject areas
- Food Science
- Animal Science and Zoology