| Autor: |
Charles P. West, Wayne K. Coblentz, T. Hess, J. A. Jennings, Donald S. Hubbell, C.R. Krehbiel, Kenneth P. Coffey, J. D. Caldwell, Charles F. Rosenkrans, R.K. Ogden, T.G. Montgomery |
| Rok vydání: |
2015 |
| Předmět: |
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| Zdroj: |
The Professional Animal Scientist. 31:577-587 |
| ISSN: |
1080-7446 |
| DOI: |
10.15232/pas.2015-01437 |
| Popis: |
Negative effects on cattle grazing tall fescue [Schedonorus arundinaceus (Schreb.) Dumort.] infected with the wild-type endophyte Neotyphodium coenophialum (E+) are well documented, but information about the carryover effects on weaned calves is limited. Our objective was to compare pre- and postweaning performance by spring-calving cows and calves grazing E+ with that by cows grazing a nontoxic endophyte–tall fescue association (NE+). Pregnant Gelbvieh × Angus crossbred cows (n = 136; 492 ± 19.2 kg of initial BW) were stratified by BW and age and allocated randomly to one of four 10-ha pastures in yr 1 (October 15) and one of eight 10-ha pastures in yr 2 (November 30). Pastures were allocated randomly before establishment to E+ or NE+. Cows remained on their assigned pastures until weaning in yr 2 but were removed from NE+ in the summer of yr 1 because of low forage mass. After weaning, calves grazed bermudagrass [Cynodon dactylon (L.) Pers.] followed by cool-season annual grasses. Cow BW and pregnancy rate, and calf weaning weight and preweaning gain were greater (P < 0.05) from NE+ versus E+. Weaning weight differentials were maintained throughout postweaning production phases, resulting in heavier HCW (P < 0.05) by steers and a tendency for greater (P < 0.10) subsequent calving rates by heifers. Therefore, replacing E+ with NE+ may improve preweaning cow and calf performance and heifer reproductive rates, but postweaning gains may not be affected by previous exposure to E+. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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