Feed conversion is the basic equation of cattle profitability – how many pounds of feed does it take to produce a pound of cattle? But it’s becoming increasingly high tech.
Dr. Ryan Reuter, agricultural research specialist for the Samuel R. Noble Foundation in Ardmore, Okla., told Ozarks Farm & Neighbor the problem with basic feed conversion is the correlation with the animal’s body weight and mature size. “If you just select for feed conversion ratio, what you’ll end up doing inadvertently over the long run is selecting for animals that are bigger and get bigger mature sizes,” he said. “That’s why Residual Feed Intake (RFI) was developed.”
RFI corrects for the animal’s body size and level of performance; it’s a complicated formula that is primarily used by academics in research. Reuter said experts believe it helps producers make better genetic decisions. “You’re going to be able to select for feed efficiency and not have negative impacts on mature size,” he said. “It is being, and needs to be, incorporated into genetic evaluations that breed associations are conducting.”
A research project at the University of Missouri could help producers make feed efficiency decisions based on genetics. Missouri Extension beef genetics specialist Dr. Jared Decker told OFN the school is using a grant from USDA to collect feed intake and growth trait measurements on thousands of cattle throughout the United States, as well as DNA samples from those animals. “We are trying to create DNA diagnostics to predict feed efficiency based on DNA markers spread throughout the genome,” he said. “We are in the process of developing these DNA diagnostics, and hope to have them available to the industry shortly.”
It’s expected the data will be used by breed associations to improve the accuracy of their EPDs, or by companies like Neogen or Zoetis that test DNA samples from cattle for the presence of specific traits. Decker said they’re using approximately 50,000 markers to calculate what’s called a genomic breeding value. “Basically, it’s an EPD calculated based on the DNA markers rather than on pedigree information and trait measurements,” he said. The producer will then be able to rank animals in the herd based on the molecular breeding value assigned to them.
Reuter added most breed associations now are moving toward using RFI rather than feed conversion in their feed efficiency calculations, and predicts that will increase in the future. He added, “A commercial producer absolutely should have feed efficiency as one of the traits in the matrix of traits that they’re selecting bulls based upon.”
