It’s a dry and dusty mid-June morning when a group of university students assembles at the 4S backgrounding lot near Wheatland, Wyo., to breed several hundred heifers from Silver Spur Ranches. They’ve been at it every day for two weeks, checking heat, synchronizing, sorting, AI-breeding and recording data on heifers, often starting and finishing in darkness under the supervision of University of Wyoming animal scientist Scott Lake, PhD, and Cheramie Viator with Silver Spur.
The group inseminated about 1,500 heifers during their stay at Wheatland, but those numbers represent just a portion of the cattle included in a multi-generation, multi-location, multi-disciplinary research and demonstration project involving universities, industry and commercial ranches.
Pfizer Animal Health technical services veterinarian John Rodgers says the project began with a discussion he had with George Perry, an animal scientist at South Dakota State University. The initial goals Rodgers and Perry discussed were to explore, demonstrate and implement ways to effectively use estrus synchronization and AI in a variety of commercial ranch settings. The project would measure biological and economic factors in evaluating the impacts of these technologies on ranch productivity and profitability. Initially the program focused on comparing AI with natural-service offspring in terms of heifer calves retained in the herd and steer calf performance through harvest, but then expanded to include genomic evaluation of cows, bulls and calves.
The project grew to include researchers at the Universities of Wyoming and Minnesota and Purdue University, several commercial ranches including Silver Spur, and additional experts from Pfizer Animal Beef Technical Services, Pfizer Animal Health Outcomes Research and Pfizer Animal Genetics. The study includes cattle in 15 locations in seven states. By the end of 2013, the fifth year of the project, researchers will have collected data on approximately 17,000 cattle.
Once the researchers complete the study and analyze the data, they expect to learn a great deal about the biological and economic impacts of using AI in multiple generations of females in commercial herds. They’ll evaluate correlations between genomic predictions, EPDs and actual performance of heifer and steer progeny for an array of traits. Lake says the data potentially could help identify genetic markers for fertility or AI pregnancy rates in replacement heifers.
We’ll have to wait for those final results, but participants say the project already has yielded valuable information and practical benefits, particularly from the educational components.
click image to zoomStudents practice their artificial-insemination techniques while University of Wyoming animal scientist Scott Lake (right) collects a hair sample for genomic testing.
Learning on the job