Autor: |
Winters, L. M., Cummings, J. N., Stewart, H. A. |
Zdroj: |
Journal of Animal Science; August 1947, Vol. 6 Issue: 3 p288-296, 9p |
Abstrakt: |
PRODUCTIVITY in brood sows during the pre-weaning period is measured by fertility, survival of the pigs born, and milk production. All three of these factors contribute to a large extent to the total weaning weight of the respective litters and are of individual economic importance to the hog producer. Therefore, from the breeder's standpoint, it is important to know to what extent these factors are related to one another or influenced by other factors in order to select effectively for greater productivity in the breeding herds already established or in the development of improved lines.High survival of the pigs born is an important goal of all swine raisers. Even though improved methods in management and certain methods of breeding have helped to lower the death loss of little pigs the problem is still of major importance. From a study of several herds under varying conditions Kernkamp (1943, 1946 ) found that the average loss of little pigs during the suckling period was about 25 percent and that the losses were due to more than 35 different diseases, disorders, or conditions. |
Databáze: |
Supplemental Index |
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