Vernon Dooley

Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)

Department / School

Animal Science

First Advisor

C. A. Dinkel


The beef industry is of paramount importance to the economic activity of South Dakota. Therefore, it is essential that information be made available which can serve as a guide to the development of increasingly more efficient beef production systems. Since total pounds of weaned calf represent the salable product of cow-calf operations, this is the characteristic of primary interest to producers and researchers. Fertility of the breeding herd, livability of calves and weaning weight of calves are all components of this profit-determining characteristic. Problems of low fertility are difficult to study, especially under range conditions were many of the nation’s beef cattle are found. Much of the work that has been has utilized dairy cattle or small numbers of beef cattle under restricted conditions. A second element shown to be important in reducing calf crops was calf death loss a or soon after birth. Performance to weaning has long been considered an economically important trait. This study was undertaken to identify some of the factors influencing level of production. A sample survey was conducted by mail to obtain relevant information from cattlemen. A mailed questionnaire was chosen because it allowed collection of the largest sample within the economical constraints and because it expedites collection and summary of information. The population samples included herds calving the springs of 1978 and 1979. A second survey was conducted in 1979 to increase sample size. Fertility was evaluated in this study as the percent of the exposed breeding herd which subsequently calved in 1978 and 1979. Herd size effects on calving rate were also examined. The percent of the exposed breeding herd which weaned a calf in 1978 and 1979 was another estimate of reproductive efficiency used in this study. This study utilized information supplied through a sequence of producer completed forms. Six questionnaires were mailed from May, 1978, to January, 1980.

Library of Congress Subject Headings

Beef cattle -- South Dakota



Number of Pages



South Dakota State University