| Title: |
PSI-13 Evaluation of acid insoluble ash as a digestibility marker in feedlot diets containing corn-milling byproducts |
| Authors: |
Spowart, Paige R; Galyean, Michael; Easom, Jordan A; Fritzler, Larry D; Lust, David G; Samuelson, Kendall L |
| Source: |
Journal of Animal Science ; volume 98, issue Supplement_4, page 273-273 ; ISSN 0021-8812 1525-3163 |
| Publisher Information: |
Oxford University Press (OUP) |
| Publication Year: |
2020 |
| Description: |
We evaluated the accuracy of acid insoluble ash (AIA) as a digestibility marker in feedlot cattle diets containing corn-milling byproducts and examined the effect of fecal sampling frequency on digestibility estimates. Steers (n = 6) were used in a crossover split-plot design where 3 steers per period were assigned to 1 of 2 diets [receiving (REC) containing 19% roughage and 38% Sweet Bran™ or finishing (FIN) containing 8% roughage and 20% Sweet Bran] typical of those used in the beef feedlot industry. Steers were limit fed at 2.0% of initial body weight. After a 21-d adaptation period, steers were housed in metabolism crates for 7 d of total collection (TC) of feed and feces and simultaneous collection of fresh manure grab samples twice daily to calculate nutrient digestibility from AIA. Grab samples were then averaged to represent 7 (7dAIA), 5 (5dAIA), 3 (3dAIA) and 1 (1dAIA) days of the collection period. No interactions (P ≥ 0.13) were observed for DM, OM or NDF digestibility between diet and method of estimating digestibility. Digestibility of DM and OM were greater (P < 0.01) for FIN than for REC, and NDF digestibility was less (P < 0.01) for FIN than REC. Both DM and OM digestibility were greater (P < 0.01) for AIA estimates than for TC; however, estimates with 7dAIA were less than 3dAIA and 1dAIA, but not different from 5dAIA. Similarly, NDF digestibility was greater (P < 0.01) for all AIA estimates than for TC, but 7dAIA and 5dAIA were less than 1dAIA and not different from 3dAIA. A treatment × method interaction (P = 0.02) occurred for ADF digestibility. These data suggest that AIA over-estimated digestibility of beef feedlot diets containing corn-milling byproducts, but accuracy improved with greater grab sampling frequency. |
| Document Type: |
article in journal/newspaper |
| Language: |
English |
| DOI: |
10.1093/jas/skaa278.492 |
| Availability: |
https://doi.org/10.1093/jas/skaa278.492; http://academic.oup.com/jas/article-pdf/98/Supplement_4/273/34595362/skaa278.492.pdf |
| Rights: |
https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model |
| Accession Number: |
edsbas.A6771BD3 |
| Database: |
BASE |