Environmental effects on neonatal mortality of beef calves
| Autor: | R. M. Koch, Larry V. Cundiff, K. E. Gregory, J. E. Kinder, L. A. Werth, Merlyn K. Nielsen, S. M. Azzam |
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| Rok vydání: | 1993 |
| Předmět: |
Male
Veterinary medicine Rain Birth weight Cattle Diseases Ice calving Biology Sex Factors Animal science Pregnancy Genetics Animals Birth Weight reproductive and urinary physiology Likelihood Functions Neonatal mortality Incidence (epidemiology) Age Factors Temperature General Medicine Dystocia Animals Newborn Cattle Female Animal Science and Zoology Food Science |
| Zdroj: | Journal of Animal Science. 71:282-290 |
| ISSN: | 1525-3163 0021-8812 |
| DOI: | 10.2527/1993.712282x |
| Popis: | Calving records from 1969 to 1989 from the Roman L. Hruska U.S. Meat Animal Research Center were used to investigate how climatic conditions, in addition to dystocia, age of dam, size of calf, and sex affect calf survival from birth to 1 wk of age. Data were analyzed separately for cows calving with (n = 11,094) or without (n = 72,187) dystocia. Neonatal mortality was described by a logit model and parameters were estimated by maximum-likelihood procedures. Calves born to cows with dystocia were five times as likely to die neonatally than calves born without assistance. Of all calves that died, 43.6% were born with difficulty. Of these calves, survival was lowest for those that were small relative to their genetic group, sex, and age of dam. Large calves had markedly increased mortality only when born to 2-yr-old dams. Average ambient temperature and precipitation on day of calving affected survival nonlinearly and the magnitude of the effect depended on age of dam, sex and size of calf, and dystocia incidence. Calves born to 2-yr-old cows were more susceptible to severe weather conditions than calves born to older cows. The negative effect of precipitation on survival increased with decreasing temperature. |
| Databáze: | OpenAIRE |
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