An assessment of the reproductive biology of Yellowstone bison (Bison bison) subpopulations using noncapture methods
| Autor: | J. C. Mccarthy, Jay F. Kirkpatrick, S. E. Shideler, D. F. Gudermuth, B. L. Lasley |
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| Rok vydání: | 1996 |
| Předmět: |
Pregnancy
Reproductive success media_common.quotation_subject food and beverages Ice calving Biology medicine.disease Bison bison Animal science Reproductive biology medicine symbols Herd symbols.heraldic_charge Animal Science and Zoology Ovulation Ecology Evolution Behavior and Systematics Feces media_common |
| Zdroj: | Canadian Journal of Zoology. 74:8-14 |
| ISSN: | 1480-3283 0008-4301 |
| DOI: | 10.1139/z96-002 |
| Popis: | Five parameters of reproductive biology (number of live calves, rates of tending lactating and nonlactating cows, and age-specific calving and pregnancy rates) were measured for the Mary Mountain (≈2500) and Northern Range (≈600) herds of bison (Bison bison) in Yellowstone National Park between 1990 and 1993. Three physiological events (ovulation, pregnancy, fetal loss) affecting reproductive success were measured using urinary or fecal steroid analysis. Adult Mary Mountain cows had significantly fewer pregnancies and calves than the Northern Range cows. Approximately 85% of cows tended by bulls, 76% of detected ovulations, and 78% of detected fall pregnancies were among nonlactating cows. Greater than 80% of all pregnancies occurred in cows ≥4 years old in both herds. However, 100% of all pregnancies among lactating cows occurred in cows ≥5 years old in both herds. In the Mary Mountain subpopulation, only 5% of all pregnancies were among cows |
| Databáze: | OpenAIRE |
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