Just about anyone involved in studying bovine reproduction is familiar with the name of Dr. George Seidel. As a university distinguished professor at Colorado State University’s College of Veterinary Medicine and Biomedical Sciences, Seidel is a leading researcher in bovine reproductive physiology. His studies have included in vitro fertilization, embryo transfer, development of sexed-semen technology for cattle, cloning and methods for improving estrous synchronization and artificial insemination.
But while Seidel is well adapted to life in the laboratory and the halls of academia, he’s also at home on the ranch, where he applies some of the latest technologies to his registered Angus seedstock herd.
Rabbit Creek Angus is located outside Livermore, Colo., about 25 miles northwest of CSU’s Fort Collins campus. In the process of producing Angus seedstock and commercial calves, the ranch also serves as a real-world laboratory for Seidel to test new methods and for CSU students to gain hands-on experience in research and application of reproductive methods.
In his breeding program, Seidel says he selects for as much weaning weight as possible while keeping birthweights down. Most of his customers come to Rabbit Creek for bulls they can use with their replacement heifers, so they look for calving ease. And they typically operate in western short-grass rangeland environments where efficiency is critical. Selection pressure in some bull lines has increased milk production to a point where nutritional demands are too high in replacement females. They can’t maintain body condition on range conditions, resulting in high feed costs or declining reproductive efficiency. “In our country, we don’t send a lunch basket out with cows,” Seidel says. “They need to utilize the forage that’s available.”
Seidel and his team use artificial insemination in the registered cow herd, with cleanup bulls for females that don’t conceive after AI service. He matches AI sires to individual females based on their combined EPDs and physical traits.
As one of the pioneering researchers in the development of sexed semen in cattle, Seidel uses the technology in his own herd. “We use sexed semen on heifers for several reasons,” he says. One benefit — when selecting for heifer calves — is that birthweights average about 5 pounds lighter than male calves, meaning less calving difficulty in first-calf heifers.