Date of this Version
Thesis (M.S.)—University of Nebraska—Lincoln, 1984. Department of Animal Science.
The survival and development of the young beef animal is dependent on the maternal environment provided by its dam. Because a primary component of this environment is the nutrition received through milk, level of milk production is of economic importance to the beef industry. To determine the optimum level of milk in overall beef production, one must consider its effect on the pre- and post-weaning performance of the calf, as well as the nutritional requirements and reproductive performance of cows at various levels of lactation. Once the desire level of milk in a system is determined, production can be increased by selection within a breed or line, or by introduction of breeds into the existing system that have superior genetic potential for producing milk.
The study was initiated in 1977 at the University of Nebraska to help determine this optimum level of milk and was conducted at the Dalbey-Halleck Farm near Virginia, Nebraska. The objective was to utilize breeds with low, medium and high genetic potential for milk production. The method of collecting milk data was designed to reflect the amount of milk consumed by each calf under natural conditions. Calf growth was measured at various times during the pre-weaning period and under a feedlot environment following weaning. The study was not designed to compare breeds, as only 12-14 sires were used in each of three groups, but rather to compare milk levels.
The study was designed to quantify the milk production of three groups of crossbred beef cows over a 205- day lactation using a calf nursing technique, and its effect on the pre- and post-weaning performance of their calves. Milking Shorthorn, Red Poll and Herford were chosen as breeds to be crossed with an Angus cow base to produce crossbred cows that were expected to vary in milk production, but be similar in genetic growth potential and mature size.
Advisor: Merlyn K. Nielsen