Feeding Bulls During Breeding Season

A bull may spend weeks walking, fighting and breeding more than eating. Going into the season in good condition, and keeping him fed through it, protects both his health and your calf crop.

Key points

Bulls often lose weight during breeding, so go in with good condition.
Provide quality feed, water and minerals through the season.
Watch for lameness, injury and illness, and call the vet.
Plan a recovery period and always handle bulls with care.

Why breeding season is hard on bulls

During breeding season, bulls travel long distances, watch cows closely, contend with other bulls and breed repeatedly. Many eat much less than normal. It is common for bulls to lose weight, and some come out of the season thin.

That makes the lead-up important. A bull that starts the season in good condition has reserves to draw on, while one that starts thin may run out of steam, lose fertility or get hurt. This is especially true on large pastures, where a bull may cover a lot of ground between water and cows. Even a calm, hardworking bull can drop in condition faster than you expect.

Condition going in

Score bulls on the 1 to 9 scale before the season, and ask your veterinarian or nutritionist what target fits your breed and age. Aim to have each bull in solid, not fat, condition, because too much fat can hurt fertility and mobility.

Give yourself time. It takes weeks to put condition on a thin bull, so start feeding well ahead of the season, not after you notice a problem. Younger bulls often need more attention than mature bulls, because they are still growing and have not yet put on their full size. Ask your vet how to handle two-year-olds differently from older animals.

Score each bull before breeding
Start feeding changes early
Avoid overfeeding to excess fat
Have a breeding soundness exam done by your vet

Feed during the season

Provide good pasture or forage along with a supplement as advised by a nutritionist. Young bulls are still growing and need more than mature bulls. Offer free access to clean water and minerals that fit your forage and region.

If bulls are in a separate pen or lot, make sure all can eat. Dominant bulls may push others off feed. Watch them daily. Feed the bulls somewhere you can see them every day. A routine check at feeding time lets you spot a bull that is off, lame or losing weight.

Watching for weight loss and trouble

Check bulls often. Look for lameness, injuries, eye problems and any sign of illness. A bull that stops working or looks thin should be looked at promptly. A lame bull cannot breed well and may be in pain.

Call your veterinarian for any injury or illness. Do not treat on your own. Meat withdrawal times on the label or from your vet must be followed exactly for any treated animal. Heat adds to the strain. Bulls working in hot weather lose condition faster, and shade and water within reach make a real difference.

Bull-to-cow ratio and management

Ask your vet or extension office what bull-to-cow ratio fits your herd, pasture size and bull age. Too many cows per bull can wear a bull down and lower pregnancy rates. Rotating or resting bulls can help in some systems.

Keep bulls of similar age and size together when possible to reduce fighting. Provide sturdy fence. Keep a written record of which bull was with which cows and for how long. It helps later when you study calving dates and pregnancy results.

After the season

When breeding ends, take stock. Score condition, check feet and legs and look for injuries. Many bulls need a recovery period with better feed to regain weight before winter.

Plan the next breeding soundness exam well ahead of the next season. Keep records of each bull's performance and condition. Ask your vet whether a post-season check is worthwhile, particularly for bulls that were injured or lost a lot of weight, because a bull that is sore or sick is a poor bet for next year.

Safety and common mistakes

Bulls are dangerous, even those that seem calm. Never turn your back on a bull, always have an escape route and use sturdy facilities. Follow manufacturer, OSHA and extension guidance for handling, and keep children away from bulls.

Common mistakes include starting the season with thin bulls, ignoring lameness, using too few bulls and failing to feed during or after breeding. Ask your nutritionist and vet what they would change in your plan.

Never trust a bull
Always have an escape route
Check feet and legs before the season

When to get help: Have your veterinarian perform a breeding soundness exam before the season and call promptly for lameness or injury, and ask a nutritionist for a ration that fits your bulls.

Sources and further reading

Organization homepages are linked so you can search them for current guidance on this topic.

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