Cow Herd Efficiency


During the Beef Improvement Federation (BIF) roundtable discussion of cow herd efficiency, Lowell Gould of the Red Angus Association of America, explained the need for screening performance data submitted for use in calculating expected progeny difference (EPD) values for animals registered by the Association. He called it a part of the responsibility to ensure integrity of the database.

“The role of a breed association is to provide a herd book and assure breed purity, but the primary function is to manage data and provide information to breeders and their customers,” Gould stated. “But there are many opportunities for errors or bias in data that are submitted.”

He said screening of data does not amount to a witch hunt. It’s about looking for bad data, not people who are trying to cheat. Skepticism regarding outliers is healthy, since factors other than genetics may influence weights, measures, dates and grouping of contemporaries. Selective reporting, said Gould, creates a very real opportunity for biased data.

Keith Long, of New Mexico’s Bell Ranch, described a research project the operation is conducting, in conjunction with Cornell University, to measure cow efficiency in a production environment. Long said the objective is to explore the relationship between inputs, in terms of the feed a cow requires, and output represented by the calf she produces.

Data collection will include cow, calf and sire identification, calf sex, birth weight and date, calf age and weight on date of weaning, as well as cow weight and body condition score (BCS) when pregnancy-checked, along with BCS at calving. Monthly climate data, forage type and quality, and stocking rates also will be logged. Long said the data will be used to evaluate the total digestible nutrients required per individual cow, compared to the weaning weight of her calf, to explore the potential correlation between cow size and cow efficiency.

Denny Crews, researcher with Agriculture and Agri-Food Canada Research Center, discussed development of a model for developing a multiple-trait selection index for cow stayability. Preliminary work indicates that cow weight may be strongly correlated to early-life production. Large cows, exhibiting higher milk production and fertility tended to have greater stayability. Crews said it may take five years of additional trials to prove the worth of this proposed selection tool.

The BIF meeting was held May 28-31, 2003, in Lexington, Ky.

— by Troy Smith