| Autor: |
Edward L. Squires, B.H. Crawford, J.R. Kubiak, G.M. Ward, R.H. Wrigley |
| Rok vydání: |
1986 |
| Předmět: |
|
| Zdroj: |
Theriogenology. 28(5) |
| ISSN: |
0093-691X |
| Popis: |
Sixty mares in transition from winter anestrus to normal cyclicity were assigned to a 3 x 2 factorial experiment to determine the effect of energy intake and percentage of body fat on the interval to first ovulation. The factors were 1) percentage of body fat--thin (11.5), good (11.5 to 15), or fat (15); and 2) energy intake--maintenance (100% of National Research Council (NRC) digestible energy requirement for maintenance) or high energy (150% of NRC digestible energy requirement for maintenance). Percentage of body fat was estimated by ultrasonographic scanning of rump fat thickness. Energy treatments began on April 2 and ended on June 4. Mares were teased daily with a stallion and their ovaries were palpated per rectum daily or every third day. A high energy intake was effective in hastening ovulation for mares in the thin group (P0.05) but not for mares in the moderate or fat groups. Mares in the fat group had a shorter (P0.05) interval from April 2 to ovulation (26.4 +/- 4.2 d) than those in the good or high energy-thin groups (48.7 +/- 2.8 and 49.1 +/- 4.2 d, respectively). Duration of the initial estrus was shorter (P0.05) for mares in the fat group (16.2 +/- 5.7 d) compared with mares in the good group (34.7 +/- 3.9 d) and tended (P0.12) to be shorter than mares in the high energy-thin group (29.0 +/- 5.7 d). |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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