Advances in AI Technology
by Heather Smith Thomas
During the past 10 years, the biggest breakthrough in improving AI techniques has been development of more effective synchronization protocols, making AI easier. All the cows can be bred on the same day instead of having to watch for heat. Conception rates have also improved.
“We’re now using timed AI, where you synchronize everything, and then on appointment you breed them all,” says Darrel Wilkes with ABS. “If you do timed AI, you’ll have more AI pregnancies than if you try to heat detect,” he says.
Willie Eltenberg of Genex says AI worked well for heifers for many years, but not as well for cows. “Advent of the CIDR changed that. Synchronization and fixed time insemination helps when working with cows, but we need an army of arms to get this accomplished. Most producers can’t breed 100 cows. The AI companies now have portable breeding barns and technicians who can do this chute-side service for the whole operation—and get those cows bred in a few hours,” says Eltenberg.
One of the most successful protocols uses the 14-day CIDR, with prostaglandin in a timed AI scenario—with a consistent average of about 65 percent conception with timed AI. “It’s great when you can get 65 percent of heifers pregnant on Day 1 of breeding season.”
At a recent AI school at Fort Collins, Colo., cost of AI versus bulls was discussed. “I asked producers what a bull would cost,” says Eltenberg. They finally arrived at $4500—though some said it’s higher and others said they can’t afford that much.
“The cost per pregnancy for a bull—figuring in the feed he ate—if you used him for 3.5 years and he gave you 25 calves per year, was $74 per calf. The cost of AI, with fixed time insemination and cleanup bulls came to $62 per calf. The producers realized that AI has never been more affordable than it is right now,” says Eltenberg.
You can select genetics for certain traits. Commercial producers can breed heifers to calving ease bulls with high growth and good maternal traits (and keep replacement heifers from that group) and breed the cows to a high performance bull or terminal sire for bigger calves to sell or to make money on retained ownership through the feedlot.
“Getting heifers to calve early in the season gives them a higher probability of remaining early-calvers for the rest of their lives,” says Wilkes. “Improved genetics is a plus, calving ease is a plus, and if those calves are 10 days older they are 20 pounds heavier. At $1.80 per pound this covers the cost of the AI program.
“Heifers are easy to AI because you don’t have to sort calves off them. Our reps can go onto a ranch, and with just a cowboy or two to push cattle through the chute, they do 200-300 heifers before lunch. The reps manage the synchronization program and bring in a breeding barn, and it’s easily accomplished,” says Wilkes.
Breeding Barns – “One thing that’s helpful for AI is specialized portable breeding barns,” says Wilkes. “These look like a horse trailer. Most of the ones we use will accommodate two cows at a time. It’s dark and quiet, which reduces stress. The cows are not restrained in any way; their head isn’t caught, so they aren’t fighting the confinement. They stand on the ground rather than a floor, which also helps keep them calm,” explains Wilkes.
“On a large ranch we usually have two of those set up, with a three-man crew in each barn. Two people are breeding and another thaws semen. With this system we can breed 200 heifers per hour,” he says.
Sexed Semen – There’s an increase in use of sexed semen in beef cattle. There’s eight to 10 percent reduction in conception using sexed semen, but the flip side is excellent results on the sex.
Sexed semen can simplify crossbreeding systems. Many ranchers are not taking advantage of heterosis because of the logistics of maintaining a crossbreeding program with natural service. With sexed semen you can maintain your base herd using female semen on your heifers. You could use male semen on the cowherd, with a terminal sire to produce crossbred steers to sell. If you are breeding heifers you can use heifer semen to reduce dystocia (since heifer calves tend to be smaller at birth), and keep replacements out of your heifers.
“We are doing trials with University of Missouri on timing of insemination with sexed semen—on fixed time protocols. Current recommendation is that sexed semen only be used with heat detection. We’d like to be able to do it with fixed time insemination, so we are doing these trials with some large ranches to see if we can adjust the timing and increase conception rate,” explains Eltenberg.