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Cattle rancher highlights transitioning bulls from feeding to breeding

by Wyoming Livestock Roundup

The hardest time for a young bull is when he’s turned out with cows for his first breeding season, after being well fed all winter and spring. Most bulls are raised in unnatural conditions.  

After weaning they are confined, fed concentrate feeds and pushed for fast growth. Many young bulls have gone through a bull test or feeding program to measure rate of gain and feed efficiency. Although most stockmen know fat is unhealthy for a bull, they still tend to buy the biggest, best-looking animals and many breeders still overfeed young bulls because it’s harder to sell a bull not pushed for faster gain.  

Over-fat bulls need to be “let down” slowly, and some don’t make the transition very well if they’ve been on “hot” rations for fast growth. They may not be as fertile if there’s too much fat in the scrotum and may not hold up; they may have permanent damage to their feet from laminitis. Bulls must be athletic and be able to stay sound, with endurance to cover a lot of territory and a lot of cows.

Even the bulls developed on growing rations are carrying more flesh than bulls raised on grass or wintered on hay. It can be a major adjustment for over-conditioned bulls when turned out with cows. Some can’t handle the sudden increase in exercise and decrease in nutrition and fall apart quickly.  

It pays to have a good transition program after producers bring a bull home. How successful it is depends on how long producers have him before he goes out with cows. Some ranchers buy bulls in the fall or winter and give them plenty of time to adjust to their new environment. Others bring new bulls home a few days or weeks before turnout. 

Some seedstock producers offer a wintering program; even if the bulls are sold in the fall the breeder keeps and feeds them – delivering them closer to breeding season, so the buyer doesn’t have to worry about keeping and feeding bulls until turnout. This works if they rely on the breeder to have the bulls in ideal working condition at the time of delivery. 

Travis Olson, of Ole Farms Athabasca, Alberta, has 1,100 registered Angus cows and 300 commercial cows.  

“The best advice is to never buy a too-fat bull, but it’s a difficult challenge.  Some bulls offered for sale have as much as 0.45 inch of back fat. This’s too much fat for bulls. If they are like this when they are 14 months old – at a March sale for January-born calves – this is equivalent to a finished steer,” he says. “A young bull with this much fat may have liver failure, his feet may fall apart and there’s more weight and stress on bones and joints. Fat bulls are more likely to put a hip out of place or have some other kind of breakdown.”

“As many as one-third of over-fat bulls will be unable to have semen frozen. Bull studs have a problem with overfat bulls. Those bulls might narrowly pass the semen test for breeding cows, but don’t have adequate quality to freeze semen. Fat is beautiful but not for reproduction,” says Olson. 

Get them home soon

If you are buying yearlings from a breeder who feeds them heavily, get them home as soon as possible.  

“Many ranchers want to leave bulls at the feedlot longer so they don’t have to worry about the bulls until closer to breeding season, but this’s not always a good idea,” he notes. “When buying bulls, get them home and turn them out with other bulls.”

“Some of our bull customers put them in a separate pen from their other bulls because they don’t want them to fight. They don’t put them together until the day of turnout with the cows,” Olson says.  

“I like having them home awhile prior to turnout. Producers can get the bulls adjusted to feed, grass, the environment, etc. Many people buy their bulls a long way away and it may be a different climate,” he continues.  

The bulls need time to adjust. Olson advises bringing them home earlier rather than later, letting them adjust and get the fighting done and pecking order established.  

“Most bulls will fight a lot, so it’s good to get this out of the way. Give them lots of space. Even if there are 50 bulls together, never have them in a pasture smaller than 40 acres,” Olson explains. “They need a big area to roam and get away from each other. If producers buy new bulls in the winter, put them in a big area but bed them in several different locations. Then the bulls taking a licking can go off somewhere else.”

Bulls in proper condition and not overfat are less likely to get hurt.  

“Bulls carrying more weight are less athletic and more likely to be seriously injured. I like to have the bulls a long way from any cows until turnout time. Then they are not trying to jump over fences or get in with the cows. If producers can get them farther away, they fight less,” says Olson.

Transition takes time 

Sperm production is a 60-day process to develop mature sperm.  

“If the bull is stressed during transport, takes a beating when he arrives or gets pushed away from the feed bunk because other bulls are beating him up, he may not eat for several days. The stress from all this can affect semen development. This is why it’s a good idea to have all of this accomplished more than 60 days ahead of the breeding season, so the sperm will be normal again by then,” says Olson.

A really fat bull that has lost weight swiftly won’t be as fertile through the breeding season.  

“Losing weight is a stress. Many yearling bulls lose as much as 400 pounds their first breeding season, and that’s very unhealthy,” he says.

“If a bull loses this much weight there’s usually something wrong with how the breeder developed the bull, or something is genetically wrong. A bull should be able to breed and still look decent, and a producer can help out by the transition,” Olson adds.

If producers find a breeder who will develop bulls right, that’s the best scenario, but this is not the way the industry typically works.  

“Most people buy too fat bulls. Producers who transition them into a better nutrition program and free-choice minerals can be very important. Producers who are feeding a total mixed ration, make sure minerals are included. Everything producers can do to promote the health of these bulls is very important,” he says.

Proper nutrition, vaccination and a healthy environment is also important. Bulls need room and a dry area rather than standing in mud in a small corral.  

“All too often people keep bulls in a tight little corral and they are more likely to get foot rot, lesions on the bottom of their feet, etc. Most years, some producers kick bulls out on 40 to 60 acres, bed them in multiple spots if they are buying bulls in March and watch closely for pinkeye and foot rot. If they take a licking, pull them out of their pen before they lose a lot of weight. If a bull gets hurt, he stops eating. If he gets beat up every time, he goes to the bunk,” says Olson.

Heather Thomas Smith is a corresponding writer for the Wyoming Livestock Roundup. Send comments on this article to

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