Controlled Breeding Seasons for Beef Herds: Planning and Benefits

By Dr. Zubair Khalid, DVM, MS, PhD · 2026-08-14

Key Takeaways

A controlled breeding season, typically 60-90 days for mature cows and 45-60 days for heifers, concentrates calving into a defined window, leading to more uniform calf crops and improved marketing opportunities.
Reproductive efficiency is paramount; a 12-month calving interval requires conception within approximately 90 days postpartum, necessitating good body condition (BCS 5-6 at calving) and timely rebreeding.
Bull management is critical, including mandatory Breeding Soundness Exams (BSE) 30-60 days pre-breeding, appropriate bull-to-cow ratios (1:25-30 for mature bulls), and maintaining bulls at BCS 5-6.
Pregnancy diagnosis 45-60 days post-bull removal is essential for identifying open females, enabling prompt culling to reduce costs and improve herd reproductive performance.
Recordkeeping of calving dates and pregnancy status is fundamental for calculating key metrics like calving interval, conception rate, and calving distribution, which drive genetic improvement and management adjustments.
Heifers require separate management, bred 21 days prior to the mature herd with a target pre-breeding weight of 60-65% of mature body weight, and should be culled if open or calving late in their first season.

A controlled breeding season is one of the most effective management tools available to beef cattle producers, yet many herds still operate without one. This guide explains what a controlled breeding season is, why it matters for herd productivity and profitability, and how to plan and implement one successfully. It is written for cow-calf producers, herd managers, and agricultural advisors who want to tighten their calving window, improve calf uniformity, and make better use of labor and pasture resources.

At a Glance

A controlled breeding season means bulls are turned in with cows for a defined period, typically 60 to 90 days, rather than running year-round.
The primary benefits are a uniform calf crop, lower calf mortality, better herd nutrition management, and improved reproductive efficiency over time.
The most common breeding season length is 60 to 90 days for mature cows and 45 to 60 days for first-calf heifers.
Calving season should be planned backward from your forage calendar, labor availability, and market goals.
Bull management is critical: breeding soundness exams, body condition, and bull-to-cow ratios all affect conception rates.
Recordkeeping is the backbone of a successful controlled breeding program. Without pregnancy diagnosis and calving dates, you cannot measure progress.
The biggest mistakes are turning bulls in too early, ignoring bull fertility, and failing to cull open females promptly.

Why a Controlled Breeding Season Matters

A controlled breeding season is a deliberate decision to limit the period during which cows can become pregnant. Instead of letting bulls run with the herd all year, you set a start date and an end date. The result is a defined calving window roughly nine months later. For most operations, that window is 60 to 90 days, though some progressive herds push toward 45 days for mature cows.

The rationale is straightforward. When calves are born over a short, predictable period, they are more uniform in age and weight. That uniformity translates into better marketing options, easier management at weaning, and a more consistent product for buyers. It also means you can concentrate your labor during calving season rather than watching for calves year-round.

Beyond marketing, a controlled breeding season improves herd health. Cows that calve in a tight group can be managed as a group for vaccination, deworming, and nutrition. You can adjust feed to match the stage of production. A cow that is lactating and trying to rebreed has different nutritional needs than a dry cow in mid-gestation. When the calving season is spread across the year, those needs are impossible to meet efficiently.

Reproductive efficiency is the single biggest driver of profitability in a cow-calf operation. A cow that calves every 12 months and weans a heavy calf is the goal. A controlled breeding season is the tool that makes that goal achievable. Without it, calving intervals stretch out, weaning weights drop, and open cows go unnoticed for months.

The Biology Behind Breeding Season Length

To plan a breeding season, you need to understand the reproductive cycle of the beef cow. The estrous cycle averages about 21 days. A cow stands to be bred for a short period, usually 12 to 18 hours, during each cycle. After calving, a cow needs time for the uterus to involute and for ovarian activity to resume. This period, called the postpartum interval, typically lasts 45 to 60 days in a well-nourished cow. Thin cows or cows that calved late in a previous season may take longer.

The postpartum interval is the limiting factor in a 12-month calving interval. If a cow calves on March 1 and you want her to calve again on March 1 next year, she must be bred by approximately June 1. That gives her a 90-day postpartum window. If she does not conceive within that window, she will calve later next year, and the drift continues.

This is why breeding season length matters. A 90-day breeding season gives every cow at least one opportunity to cycle and be bred, assuming she is cycling by the time bulls are turned in. A 60-day season is tighter and requires cows to be in good body condition at calving. A 45-day season is aggressive and is best reserved for mature cows with a proven history of calving early in the season.

For heifers, the timeline is different. Heifers must reach puberty and be cycling before the breeding season starts. Target weight at breeding is typically 60 to 65 percent of mature body weight. A heifer that weighs 550 pounds at breeding and will mature at 1,100 pounds is on track. Heifers also need a longer postpartum interval after their first calf because they are still growing themselves. Many producers breed heifers 21 days before the mature cow herd so they have extra time to recover before the next breeding season.

Setting Your Calving Season

The most important planning decision is choosing when you want calves to be born. This decision drives everything else, including when to turn bulls in, when to pregnancy check, and when to wean. There is no single correct calving season. The right choice depends on your climate, forage program, labor, facilities, and market.

In most of North America, spring calving is the most common system. Calves are born in February, March, or April, depending on the region. Spring calving aligns with the natural forage flush. Cows are lactating and rebreeding just as pasture quality improves. Calves are weaned in the fall when they are 6 to 8 months old. This system works well for operations that rely on grazed forage and want to minimize harvested feed costs.

Fall calving is the other major option. Calves are born in September, October, or November. Cows calve on dry lots or in confinement, and calves are weaned in the spring. This system can capture higher calf prices in some years because there is less supply competing at sale time. Fall calving also spreads labor across the year and can make better use of crop residues. The downside is that cows are lactating through the winter, which increases feed costs.

Some producers choose a split season, calving in both spring and fall. This spreads risk and can smooth cash flow, but it doubles the labor and facility demands. For most operations, a single, well-planned calving season is simpler and more profitable.

Once you choose a calving season, work backward to set the breeding season. Gestation in cattle averages 283 days, roughly 9.5 months. If you want calves on the ground starting March 1, turn bulls in around May 20. If you want a 60-day calving window, remove bulls on July 20. Mark these dates on the calendar and treat them as fixed commitments.

Choosing Breeding Season Length

Breeding season length is a trade-off between genetic progress and reproductive pressure. A shorter season means more uniform calves and faster genetic improvement, but it also means more cows may be open at pregnancy check. A longer season is more forgiving but dilutes the benefits of a controlled program.

The industry standard for mature cows is 60 to 90 days. Many seedstock producers use 60 days or fewer because they want early calves and are willing to cull harder. Commercial producers often use 75 to 90 days because they want to give every cow a fair chance to rebreed. The key is to pick a length and stick with it for several years so you can measure progress.

For first-calf heifers, a shorter breeding season of 45 to 60 days is recommended. Heifers are the genetic future of the herd, and selecting for early puberty and early rebreeding pays dividends. Heifers that calve early in their first season tend to calve early for the rest of their lives. Culling heifers that do not breed in the first 45 days removes late-calving genetics from the herd.

The actual number of estrous cycles a cow gets during the breeding season depends on season length. In a 60-day season, a cow that is cycling at turnout has about three opportunities to conceive. In a 90-day season, she has about four opportunities. Conception rate per service is typically 60 to 70 percent, so most cycling cows will conceive within two or three cycles. Cows that are not cycling at turnout, due to poor body condition or a long postpartum interval, are the ones that end up open.

Bull Management for Controlled Breeding

A controlled breeding season only works if the bulls are ready to work. Bull management starts long before turnout. A breeding soundness examination, or BSE, should be performed by a veterinarian 30 to 60 days before the breeding season begins. The BSE evaluates physical soundness, reproductive tract health, and semen quality. A bull that fails a BSE is a costly problem if he is turned out with the herd, because he can cause a whole group of cows to come up open.

Bull to cow ratio is another critical factor. For mature bulls in a pasture breeding situation, a ratio of 1 bull to 25 to 30 cows is typical. For yearling bulls, use 1 bull to 15 to 20 cows. If you are using multiple bulls, they need to be in the same pasture together long enough to establish a social hierarchy before cows are turned in. Introducing bulls and cows at the same time can lead to fighting that disrupts breeding activity.

Body condition on bulls matters too. A bull that is too thin lacks the stamina for a long breeding season. A bull that is too fat may have reduced libido and fertility. Target a body condition score of 5 to 6 on bulls at turnout. Bulls should be fed to maintain condition through the breeding season, especially if they are covering rough country or large pastures.

Many producers make the mistake of leaving bulls in with the cows after the breeding season ends. This defeats the purpose of a controlled program. Pull bulls out on the scheduled date and move them to a separate pasture. If you want to extend the season for late-calving cows, do that deliberately and only for a defined group, not for the whole herd.

Nutrition and Body Condition

Nutrition is the single biggest factor in reproductive success. Cows that are in good body condition at calving are more likely to cycle early and rebreed. Cows that are thin at calving have a longer postpartum interval and are more likely to be open at pregnancy check.

Body condition scoring is a practical tool for assessing nutritional status. The scale runs from 1 to 9, with 1 being emaciated and 9 being obese. A target body condition score of 5 to 6 at calving is recommended for mature cows. Heifers should be at a 6. Cows that calve at a body condition score of 4 or lower will have delayed return to estrus.

The critical period for nutrition is the last trimester of gestation and the first 60 days of lactation. This is when the cow has the highest nutrient demands. If she is underfed during this window, she will lose condition and her reproductive performance will suffer. The damage is difficult to reverse once the breeding season starts.

Feed costs are the largest variable expense in a cow-calf operation, and a controlled breeding season helps you use feed more efficiently. When all cows calve in a defined window, you can feed them as a group. You do not need to maintain a high plane of nutrition for months on end waiting for stragglers to calve. You can match feed inputs to the stage of production and reduce waste.

For operations in cold climates, calving season timing also affects feed requirements. A February calving herd needs higher quality hay during the coldest months. A May calving herd can calve on grass and reduce harvested feed costs. The trade-off is that May calves are smaller at weaning and may miss the best market prices.

Heifer Development and Breeding

Heifer development deserves special attention in a controlled breeding program. The decisions you make with heifers determine the genetic direction of the herd for years to come. Heifers that are bred early and calve early are more productive over their lifetimes. Heifers that calve late tend to stay late, and heifers that do not calve at all should be culled without hesitation.

Start with replacement heifers that are structurally sound, have good maternal traits, and come from cows that calve early in the season. Target a prebreeding weight of 60 to 65 percent of mature body weight. For most British and Continental breeds, that means 600 to 700 pounds at breeding for heifers that will mature at 1,100 to 1,200 pounds.

Heifers should be bred 21 days before the mature cow herd. This gives them a longer postpartum interval before their second breeding season. It also means their calves are older and heavier at weaning, which helps them rebreed on schedule. Use calving ease bulls on heifers, and be prepared to assist with dystocia.

After heifers calve, they need extra nutrition to support both lactation and continued growth. First-calf heifers should be managed as a separate group from the mature cow herd for at least the first 60 days after calving. They need higher quality feed and should not have to compete with mature cows for bunk space or pasture.

Pregnancy check heifers 45 to 60 days after the breeding season ends. Cull any heifer that is open. The cost of keeping an open heifer through the winter is money that could be spent on a better replacement. Heifers that calve late in their first season should also be considered for culling, because they will likely calve late for the rest of their lives.

Pregnancy Diagnosis and Culling Decisions

Pregnancy diagnosis is the checkpoint that makes a controlled breeding season work. Have a veterinarian or trained technician pregnancy check all cows 45 to 60 days after the bulls are removed. This tells you which cows are pregnant and how far along they are. Cows that are open should be culled immediately or at weaning, depending on your marketing plan.

The timing of pregnancy check matters. Too early, and some pregnancies may be missed. Too late, and you have been feeding open cows for months. The ideal window is between 45 and 90 days after the breeding season ends. Rectal palpation can be done from about 35 days after conception. Ultrasound is accurate from about 28 days and also allows you to determine fetal age and sex.

Fetal age data is valuable for sorting cows into calving groups. Cows that conceived in the first 21 days of the breeding season will calve in the first 21 days of the calving season. These are your most fertile cows, and their calves are the oldest and heaviest at weaning. Cows that conceived later are less fertile and should be marked for closer scrutiny.

Culling open cows is the hardest part of a controlled breeding program for many producers, but it is essential. An open cow costs money every day she is in the herd. She eats feed, occupies pasture, and contributes nothing. The only exception is a young cow with a calf at side that is open for the first time. Some producers give her one more chance if she is in good condition and has a strong calf. But if she is open again, she goes.

Cows that calve late in the season are also culling candidates. If you have a 60-day calving season, a cow that calves on day 55 will be at a disadvantage for the rest of her life. Her calf will be lighter at weaning, and she will be under more pressure to rebreed on schedule. Culling late calvers tightens the calving window over time and improves the genetic base of the herd.

Recordkeeping and Measuring Progress

You cannot manage what you do not measure. A controlled breeding season generates a wealth of data, but only if you record it. The minimum records for each cow are her identification, calving date, and pregnancy status. From these three pieces of data, you can calculate calving interval, conception rate, and the percentage of cows calving in the first 21 days of the season.

Calving date is the most important record you can keep. It tells you when the cow conceived and how she fits into the breeding season. A cow that calves on day 10 of the calving season is a valuable asset. A cow that calves on day 55 is a liability. Over several years, calving date data lets you identify cows that consistently calve early and cows that consistently calve late.

Pregnancy rate is the percentage of cows exposed to bulls that become pregnant. A pregnancy rate of 90 percent or higher is a reasonable goal for a well-managed herd. If your pregnancy rate is below 85 percent, look for problems with bull fertility, nutrition, or disease. Body condition at calving is often the culprit.

Calving distribution is the percentage of calves born in each 21-day period of the calving season. A tightly grouped herd will have 60 to 70 percent of calves born in the first 21 days. If your distribution is spread evenly across the season, your cows are not cycling early enough or your bulls are not getting the job done.

Use a simple spreadsheet or a commercial herd management software to track these numbers. Many producers also use ear tags with different colors to mark cows by calving group. The goal is to make the data easy to collect and easy to interpret. Review the numbers every year after pregnancy check and adjust your management accordingly.

Common Mistakes in Controlled Breeding Programs

The most common mistake is setting a breeding season but not following through. Producers turn bulls in on schedule, then leave them in for another month because they want to give late cows another chance. This erodes the entire program. The breeding season end date is as important as the start date.

A second mistake is ignoring bull fertility. A bull that fails a breeding soundness exam is a time bomb. Even a bull that passes may have reduced fertility if he is too thin, too fat, or lame. Check bulls before turnout and monitor them through the season. A bull that is injured or losing condition needs to be replaced immediately.

A third mistake is poor bull to cow ratios. Running one bull with 50 cows may work in a small pasture with a highly fertile bull, but it is a gamble. The standard recommendation of 1 bull to 25 to 30 cows exists for a reason. Overworked bulls have lower conception rates, and the result is a drawn-out calving season.

A fourth mistake is failing to adjust nutrition for body condition. Producers know their cows are thin but hope they will cycle anyway. They do not. The postpartum interval is directly tied to body condition. If cows are thin at calving, they will be late to rebreed, no matter how good the bulls are.

A fifth mistake is not pregnancy checking. Some producers skip the pregnancy check to save money. This is false economy. An open cow eats for months before you discover she is not pregnant. Pregnancy check is one of the highest return investments in the entire operation.

A sixth mistake is keeping problem cows too long. A cow that is open, has a bad udder, is a poor mother, or has a bad disposition should be culled. The longer you keep her, the more she costs you and the more she passes her problems to her calves.

Monitoring During the Calving Season

Calving season is when your breeding season planning pays off. A controlled calving season means you can concentrate your attention on a defined period. You can check cows more frequently, intervene sooner when problems arise, and keep better records of what happens.

Check cows at least twice daily during calving season, and more often for heifers. A cow that is in labor for more than two hours without progress needs assistance. A heifer that is in labor for more than one hour needs help. Early intervention saves calves and reduces stress on the cow.

Keep a calving log with the date, cow identification, calf sex, birth weight, and any problems. This data is valuable for evaluating the breeding season and for making culling decisions. Calves that are born unassisted and weigh in a desirable range come from cows that are doing their job.

Colostrum is critical. Calves need to nurse within the first 6 to 12 hours of life to get adequate antibodies. A calf that is slow to nurse or a cow with a tight udder may need assistance. Have colostrum or a colostrum replacer on hand for emergencies.

Weather is a major factor in calving success. A cold, wet spring can cause hypothermia in newborn calves. Have a place to warm calves and a protocol for dealing with cold stress. Conversely, hot weather can cause calves to dehydrate quickly. The labor you save with a tight calving season can be reinvested in better observation and care.

When to Call a Veterinarian or Extension Agent

A controlled breeding season is a management program, not a veterinary procedure. But there are times when professional help is essential. The following situations warrant a call to your veterinarian or local extension agent.

If your pregnancy rate drops below 85 percent for two consecutive years, you have a problem that needs investigation. A veterinarian can check bulls, test for reproductive diseases, and evaluate your nutrition program. Extension agents can help with forage testing and ration balancing.

If you see a pattern of early embryonic death or abortions, call your veterinarian immediately. Diseases like infectious bovine rhinotracheitis, bovine viral diarrhea, and leptospirosis can cause reproductive losses. These diseases are often manageable with vaccination, but you need a diagnosis first.

If heifers are not reaching puberty by breeding age, an extension agent can help you evaluate your heifer development program. Target weight is the most common issue. Heifers that are too light at breeding will not cycle. A nutritionist can help you design a feeding program that gets heifers to target weight without overconditioning them.

If bulls are failing breeding soundness exams at a high rate, your veterinarian can help determine why. Testicular development, semen quality, and physical soundness are all part of the exam. Some problems are genetic and should be selected against. Others are management related and can be corrected.

If you are considering changing your calving season, talk to an extension agent or a nutritionist first. They can help you evaluate the forage, feed, and labor implications of a different calving window. A change that looks good on paper may not work in your specific environment.

Economics of a Controlled Breeding Season

The economics of a controlled breeding season are compelling, though the benefits take time to appear. The first year you implement the program, you will likely see little change. Cows that are already in the herd have established calving patterns. The full benefit appears over three to five years as you cull late calvers and keep replacements from early calving cows.

The most direct economic benefit is calf uniformity. A group of calves that are within 60 days of age and similar in weight will bring a premium at sale time. Buyers pay more for uniform lots because they are easier to manage and have predictable performance. A group of calves spread over 150 days in age is harder to sell and brings a discount.

A second economic benefit is reduced labor. A controlled calving season means you are not checking cows every day for six months. You can plan your labor around a 60 to 90 day window. This is especially valuable for producers who have off-farm jobs or limited help.

A third benefit is lower feed costs. When cows calve in a tight group, you can feed them to match their stage of production. You do not need to keep the whole herd on a high plane of nutrition for months waiting for late calvers. This can reduce winter feed costs by 10 to 20 percent.

A fourth benefit is improved reproductive efficiency. Cows that calve early and rebreed early stay in the herd longer. Each additional calf a cow produces spreads her fixed costs over more output. A cow that produces eight calves in her lifetime is more profitable than one that produces six.

The costs of a controlled breeding program are modest. You may need to invest in better bull management, including breeding soundness exams and possibly more bulls. You will need to pregnancy check, which costs money but pays for itself many times over. And you will need to cull more aggressively, which means selling some cows you might have kept.

Adapting the Program to Your Operation

No two beef operations are the same, and a controlled breeding program must be adapted to your specific circumstances. The principles are universal, but the details will vary based on herd size, facilities, labor, and goals.

Small herds of 25 to 50 cows can run a tighter breeding season than large herds. With fewer animals, you can observe cows more closely and intervene sooner. A 45 to 60 day breeding season is feasible for a small herd with good bull management. Large herds of 200 or more cows may need a 75 to 90 day season to accommodate the logistics of moving cows and bulls.

Operations with multiple pastures can use a rotational breeding system. Divide the cow herd into groups based on calving date and breed each group separately. This allows you to use different bulls for different groups and to manage nutrition more precisely. It also reduces bull power requirements because each group is bred for a shorter period.

Operations with limited facilities may need to plan around their constraints. If you only have one handling facility, schedule breeding season so that pregnancy check and vaccination can be done in one pass. If calving facilities are limited, choose a calving season that matches your ability to provide shelter.

Producers who retain ownership of calves through the feedlot have different goals than those who sell at weaning. Retained ownership rewards calves that perform well in the feedlot, which is correlated with uniformity and genetic potential. A controlled breeding season is even more valuable when you are feeding the calves yourself.

Integrating Vaccination and Herd Health

A controlled breeding season creates natural checkpoints for herd health management. Vaccination schedules can be tied to the breeding season and calving season. This ensures that cows have immunity when they need it most.

Prebreeding vaccination is important for reproductive diseases. Vaccines for infectious bovine rhinotracheitis, bovine viral diarrhea, leptospirosis, and campylobacteriosis are commonly given 30 to 60 days before breeding. These vaccines protect the cow and the developing fetus. Your veterinarian can recommend a vaccination program based on your herd history and risk factors.

Precalving vaccination boosts colostrum quality. Vaccinating cows 4 to 6 weeks before calving increases the antibodies in colostrum, which protects calves from scours and respiratory disease. This is especially important for calves born in high risk environments.

Parasite control should also be integrated into the breeding season calendar. Deworming cows at pregnancy check reduces parasite load and improves body condition. Treating bulls before breeding season reduces the chance of spreading parasites through the herd.

The key is to combine handling events. Do as many procedures as possible at pregnancy check, prebreeding, and precalving. This reduces stress on the animals and saves labor. A well planned herd health calendar is a natural companion to a controlled breeding season.

Genetic Improvement Through Controlled Breeding

A controlled breeding season is a powerful tool for genetic improvement. When you select replacements from cows that calve early in the season, you are selecting for early puberty and early rebreeding. These traits are moderately heritable and respond to selection.

The first 21 days of the calving season is the most valuable genetic window. Calves born in this period come from cows that conceived early in the breeding season. These cows have above average fertility. Their calves should be your first choice for replacements.

Cows that calve in the second 21 day period are acceptable but not ideal. Cows that calve in the third period should be culled unless they have exceptional other traits. Cows that calve after the breeding season ends are the first to go.

Bull selection is also part of the genetic program. Use expected progeny differences, or EPDs, to select bulls that will improve calving ease, growth, and maternal traits in your herd. A controlled breeding season makes it easier to evaluate bull performance because you can see which bulls sired calves early in the season.

DNA testing is an emerging tool that can accelerate genetic progress. Testing calves for parentage and genetic defects allows you to make more informed culling and selection decisions. This is especially useful in multi-sire breeding pastures where parentage is unknown.

Troubleshooting a Poor Breeding Season

If your breeding season results are disappointing, work through the problem systematically. Start with the bulls. Were they sound and fertile? Did they have adequate body condition? Were there enough bulls for the number of cows? A bull problem will show up as a high percentage of open cows or a drawn out calving season.

Next, look at the cows. Were they in adequate body condition at calving and at breeding? Thin cows will have a long postpartum interval and will not cycle early. Were there health problems like foot rot or mastitis that affected breeding? Were cows carrying calves from the previous season?

Nutrition is the next suspect. Were cows getting enough energy and protein in the last trimester and early lactation? Was there a mineral deficiency? Selenium, copper, and phosphorus are all important for reproduction. A forage test can identify deficiencies.

Disease is another possibility. Reproductive diseases like bovine viral diarrhea and leptospirosis can cause early embryonic death and infertility. If you suspect disease, work with your veterinarian to test and implement a control program.

Finally, look at your management. Did you turn bulls in on schedule? Did you remove them on schedule? Did you pregnancy check and cull open cows? A controlled breeding season requires discipline. If you let the season drift, the results will drift with it.

Long Term Planning and Seasonal Adjustments

A controlled breeding season is not a one time change. It is an ongoing program that requires annual planning and adjustment. Review your results every year and make small changes to improve the program.

Weather is a major variable that affects breeding success. A drought that reduces forage quality will lower body condition and delay estrus. A harsh winter will increase feed costs and may affect calving success. You cannot control the weather, but you can plan for it. Keep a reserve of feed for dry years and adjust stocking rates to match forage availability.

Market conditions also influence breeding season decisions. Calf prices vary by season and by weight. If fall calves are bringing a premium, you may consider shifting your calving season. If heifers are selling well, you may sell more heifers and buy replacements rather than raising them.

Labor availability is another factor. If you have help available during certain months, schedule calving season to match. If you are short on labor, you may need a longer calving season or additional facilities to reduce the workload.

The best approach is to set a plan, follow it for three to five years, and evaluate the results. Changing your breeding season every year is counterproductive. Cows need time to adapt to a new schedule, and your records need time to show trends.

Frequently Asked Questions

How long should my breeding season be?

For mature cows, 60 to 90 days is the standard recommendation. A 60 day season is more intensive and gives faster genetic progress. A 90 day season is more forgiving and works better for large herds or operations with limited labor. For first calf heifers, use 45 to 60 days to select for early calving.

When should I turn bulls in with the cows?

Work backward from your desired calving date. Gestation is about 283 days. If you want calves to start arriving on March 1, turn bulls in around May 20. If you want a 60 day calving window, remove bulls on July 20. Mark these dates on the calendar and stick to them.

How many cows can one bull breed?

A mature bull can breed 25 to 30 cows in a pasture breeding situation. Yearling bulls should be limited to 15 to 20 cows. If you are using multiple bulls in the same pasture, turn them in together several weeks before breeding so they establish a social order.

What is a breeding soundness exam and why does it matter?

A breeding soundness exam is a veterinary evaluation of a bull's physical soundness, reproductive tract, and semen quality. It is performed 30 to 60 days before breeding. A bull that fails a BSE is a serious problem because he can cause a large group of cows to come up open. Never turn out a bull without a current BSE.

How do I know if my cows are pregnant?

Have a veterinarian or trained technician pregnancy check your cows 45 to 60 days after the bulls are removed. Rectal palpation and ultrasound are both accurate methods. Pregnancy check is the only way to know which cows are open and need to be culled. It is one of the best investments you can make.

What body condition should cows be at calving?

Mature cows should be at a body condition score of 5 to 6 at calving. Heifers should be at a 6. Cows that calve at a body condition score of 4 or lower will have a delayed return to estrus and are less likely to rebreed on schedule. Thin cows are the most common cause of a poor breeding season.

Should I breed heifers separately from mature cows?

Yes. Heifers should be bred 21 days before the mature cow herd and managed as a separate group. They need extra nutrition and should not have to compete with mature cows. Breeding heifers early gives them a longer recovery period before their second calving.

What do I do with open cows at pregnancy check?

Cull them. An open cow costs money every day she is in the herd. The only exception is a young cow with a calf at side that is open for the first time. You may give her one more chance if she is in good condition, but if she is open again, she goes.

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Controlled Breeding Seasons for Beef Herds

This section will be populated with links to related guides on beef cattle management, calving season planning, herd nutrition, and reproductive management. Check back for updates or explore other articles in the beef cattle category.

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References

Beef Cattle Research Council: https://www.beefresearch.ca/
USDA APHIS Cattle Health: https://www.aphis.usda.gov/livestock-poultry-disease/cattle
WOAH Terrestrial Animal Health Code: https://www.woah.org/en/what-we-do/standards/codes-and-manuals/terrestrial-code-online-access/
FAO Animal Production and Health: https://www.fao.org/animal-production/en/
WOAH (World Organisation for Animal Health): https://www.woah.org/en/home/

This article is educational and is not a substitute for veterinary diagnosis, treatment, public-health guidance, or regulatory reporting.