Sexed-semen breeding programs for the beef industry have primarily focused on developing genetically superior replacement heifers.
“Male sexed semen is an opportunity to capture value,” said Ken Odde, professor and department head emeritus of the department of animal sciences and industry at Kansas State University. “The opportunity’s greater when the price spread between steers and heifers is significant.”
Since retiring from academia, Odde has focused on creating more profitability for his family’s commercial cow-calf ranch in South Dakota.
“About six years ago, I was sitting at the sale barn in Mobridge, South Dakota, and the price spread between steers and heifers just struck me that day,” Odde said.
From that “aha” moment, Odde started to pursue what a sexed-semen breeding program could look like for his ranch. He shares strategies and protocols to consider for success, including fertility differences between cows and heifers, the use of split-time or fixed-time artificial insemination (A.I.) and the value of using breeding indicator patches to measure estrus intensity.
Whether using a fixed-time or split-time A.I. breeding schedule, breeding indicators are important tools to ensure the best chance at efficacy. Photo courtesy of Estrotect.
Value of breeding for males
Before breeding with sexed semen, Odde looked back at industry trends to see the economic impact of breeding for more males.
“We’ve got years of history when most sexed semen was targeted at producing females,” Odde said. “Breeding for males is a shift in thinking, and ultimately it’s driven by how high the price difference is between steers and heifers.”
Data from Superior Livestock (see Table 1) shows the price per hundredweight (cwt) difference between steers and heifers has been on an upward trend for nearly three decades. Odde says the price difference between steers and heifers has been primarily driven by increasing carcass weights and the rising cost of gain.
Feedlot closeout performance data in Kansas (see Table 2) from August 2017 showed the average cost of gain was $5.66 per cwt higher for heifers versus steers. That year, corn was relatively cheap to feed at $3.91 per bushel. In August 2022, the average cost of gain was $12.77 per cwt higher for heifers than for steers when the corn price was $8.69 per bushel.
“Steers can be fed to higher weights more efficiently,” Odde said. “The trend of increasing carcass weights could be a driver of producing more male calves with sexed semen, particularly when feed prices are higher.”
On-ranch experience
The first set of females to be bred with sexed semen on Odde’s ranch used maternal female sexed semen on heifers (see Table 3) and predominantly utilized terminal male sexed semen on cows (see Table 4).
Following an estrus synchronization protocol, heifers were bred by visual heat detection using Estrotect breeding indicator patches to aid in estrus detection during five days of monitoring. The heifers’ A.I. pregnancy rate was 63.4%.
In the first year, cows were bred using multiple protocols. With fixed-time A.I., cow reproduction rates were 40.9%. Two cow groups were bred using split-time A.I. at 70 hours post-prostaglandin injection for cows with activated patches. If patches weren’t activated, insemination happened at 90 hours with an injection of gonadotropin-releasing hormone (GnRH). The split-time groups had pregnancy rates of 45% and 47%, respectively.
“We think with split-time A.I. we were able to pick up a few more cows running them through a second time,” Odde related. “However, it is pretty labor-intensive, so we’ve moved toward more fixed-time A.I. with the cows.”
In the third year of research, male sexed semen was used across all the heifers and cows.
“We have learned we get better fertility on our yearling heifers than on mature cows,” Odde said. “We can easily produce more bull calves from our heifers, so that’s something we want to evaluate further.”
Some breeding indicators have easy-to-read bull's-eyes (black surface ink) on them. Once the bull's-eye or the equivalent surface area is rubbed off, the animal is ready to breed and is up to three times more likely to result in a confirmed pregnancy. Photo courtesy of Estrotect.
Words of advice
For producers considering breeding with sexed semen, Odde had a few tips.
Odde suggested using a protocol that helps make chuteside breeding decisions based on estrus intensity via a breeding indicator patch. If half of the patch or more is rubbed off, females are good candidates to be bred with sexed semen. Should less than half of the patch surface ink be rubbed off, it’s best to use less expensive conventional semen to help manage costs of your genetics investment.
Keeping an eye on market trends is another management practice to consider.
“You need an understanding of the economic dynamics,” Odde said.
For some herds, it may work better to develop more replacement heifers via sexed semen and marketing those replacements to terminal-focused operations, particularly when replacement females are in demand.
“It could be that male sexed semen works well in some situations, and a few years later, it may not have the same incentive,” Odde added. “When there is a good price difference between steers and heifers, it can really work well.”
Odde presented his on-ranch research findings during the Beef Improvement Federation Annual Symposium in Calgary, Alberta, on July 3.
