# Cattle Breeding Chart: Planning Your Herd's Genetic Future ## Key Takeaways - A 60 to 90-day breeding season is critical for producing a uniform calf crop, simplifying herd health management, and improving sale value by tightening the calving window. - Working backward from a target calving start date, using the average beef cattle gestation of 283 days, establishes the essential bull turnout and removal dates for the breeding calendar. - Bull selection must prioritize matching genetics to specific herd weaknesses and market demands, utilizing Expected Progeny Differences (EPDs) for traits like calving ease, weaning weight, and docility, rather than solely relying on popularity. - Heifers require a separate breeding schedule, initiated approximately three weeks prior to the mature cow herd, to allow for extended recovery post-calving and ensure timely rebreeding for their second calf. - Maintaining a Body Condition Score (BCS) of 5 or higher at calving and breeding is paramount for reliable cycling and conception rates, necessitating proactive nutritional management and targeted supplementation. - Comprehensive record-keeping, including calving dates, calving ease scores, weaning weights, and body condition scores, is fundamental for accurate genetic progress assessment and informed culling decisions. --- A [cattle breeding chart](/knowledge/animal-farming/beef-cattle/cattle-breeding-chart-a-visual-guide-to-genetic-planning) is one of the most practical tools a beef producer can use to bring order to the breeding season, tighten the calving window, and make genetic progress that shows up in the sale barn and the bank account. This guide covers how to build a breeding calendar that fits your operation, how to select bulls and replacement heifers with clear goals in mind, and how to track breeding data so you can make better decisions next year. It is written for commercial cow-calf producers, seedstock operators, and anyone managing a small herd who wants a more predictable calving season and a more profitable calf crop. ## At a Glance | Topic | Key Takeaway | |---|---| | Breeding window | Aim for a 60 to 90 day breeding season to create a uniform calf crop and simplify herd health work | | Calving season | Work backward from your target calving start date to set your breeding start date using a 283 day average gestation | | Bull selection | Match bull genetics to your herd's weaknesses, not just to what is popular in the sale ring | | Bull power | Use one mature bull per 25 to 30 cows in a controlled season, more if you are breeding heifers | | Heifer breeding | Breed heifers 3 weeks before the main cow herd so they have more time to resume cycling after their first calf | | Body condition | Cows need a body condition score of 5 or better at breeding to cycle and conceive reliably | | Record keeping | Track breeding dates, bull turnout dates, calving ease scores, and weaning weights every single year | | Genetic progress | Select for a small number of traits that matter to your market, not 15 traits at once | ## Why a Breeding Chart Matters A [cattle breeding chart](/knowledge/animal-farming/beef-cattle/cattle-breeding-chart-a-visual-guide-to-genetic-planning) is not a piece of paperwork you fill out once and forget. It is a planning tool that connects the calendar to your herd's biology, your pasture resources, and your marketing goals. When you map out your breeding season on paper, you can see the whole year at a glance: when bulls go in, when cows should calve, when you will wean, and when you will have calves ready for market. Without a chart, breeding decisions tend to happen by accident. The bull goes in when someone gets around to it. Calves arrive over five or six months. Weaning weights vary widely because the calves are not the same age. Cows that calve late in the season stay in the herd because nobody tracks their history. Over time, the herd drifts toward later calving, lower fertility, and less uniformity. A breeding chart is the tool that prevents that drift. The chart also forces you to make decisions in advance. You decide when you want calves on the ground before the bull is turned out. You decide which cows stay and which cows go before you are trying to sort cattle in the mud. You decide what traits matter most to your market before you are standing at a bull sale with a catalog in your hand. That kind of advance planning is what separates a managed breeding program from a passive one. ## Building Your Cattle Breeding Calendar ### Step 1: Set Your Calving Season Goal Every breeding calendar starts with a target calving season. For most commercial herds in North America, the goal is a 60 to 90 day calving window that starts in late winter or early spring. The exact dates depend on your climate, your feed resources, and your market. Ask yourself these questions before you set dates: - When does your spring grass typically start growing? - When do you want calves to be old enough to take advantage of that grass? - What is your marketing window for weaned calves? - When does your labor situation allow for intensive calving observation? - What is your facilities capacity for calving in bad weather? A common approach is to target a calving window that begins about 30 to 45 days before your expected spring grass flush. That way cows are at peak lactation and peak nutrient demand just as forage quality is rising. Calves are old enough to start grazing with their dams when the grass is at its best, and they will be heavier at weaning because they had a longer grazing season. If you sell calves at weaning in the fall, work backward from your ideal weaning date. A calf born in February will be 7 to 8 months old at an October weaning and should weigh more than a calf born in April. If you retain ownership or sell yearlings, the calving date shifts earlier so the calves have more time to grow before grass runs out. ### Step 2: Calculate the Breeding Window Once you know when you want calves to start arriving, count backward 283 days. That is the average gestation length for beef cattle. Some cows will calve a few days early and some will run a few days late, but 283 days is the standard planning number. For example, if you want calving to start on February 15: - Count back 283 days from February 15 - That puts your bull turnout date around May 9 - If you run a 75 day breeding season, pull the bulls around July 23 - Your last calves will arrive around May 2 the following year Write these dates on your breeding chart before you do anything else. These are the anchor dates that the rest of your management calendar hangs on. ### Step 3: Plan the Breeding Season Length The length of your breeding season is one of the most important decisions you will make. A shorter season creates a more uniform calf crop, which is worth real money at sale time. A longer season gives cows more chances to conceive but spreads out your labor and produces a ragged calf crop. Here are the common options: | Season Length | Pros | Cons | |---|---|---| | 45 days | Very uniform calves, tight calving window, easier to manage herd health | Requires cows in excellent condition, less forgiveness for late calvers | | 60 days | Good balance of uniformity and fertility, standard for many commercial herds | Some spread in calf ages at weaning | | 90 days | More chances for cows to breed back, more forgiving in tough years | Wide spread in calf weights, more labor at calving | | 120 days or longer | Maximum opportunity to get cows pregnant | Very uneven calf crop, hard to manage nutrition and health, masks fertile cows | Most commercial herds should aim for 60 to 90 days. If you are just starting to tighten up a long breeding season, do not jump straight to 45 days. Move to 90 days first, cull the cows that calve late, and tighten the window by 15 days every couple of years as your herd fertility improves. ### Step 4: Separate Heifers from Cows Heifers need a different breeding schedule than mature cows. First-calf heifers take longer to resume cycling after calving because they are still growing while they are lactating. They also need more time to recover from the stress of their first calving before they are expected to breed back. The standard practice is to breed heifers 3 weeks before the main cow herd. This gives them extra time to cycle and conceive for their second calf. It also means they calve earlier in the season, which gives them a longer recovery window before their second breeding. Here is how that works with the example dates above: - Heifer bull turnout: April 18 - Heifer breeding season: 45 to 60 days - Main herd bull turnout: May 9 - Main herd breeding season: 60 to 75 days - Heifers start calving: January 26 - Main herd starts calving: February 15 The heifers calve first, which also means you can watch them more closely before the main calving rush starts. That extra observation time is valuable for first-calf heifers, which are the most likely animals to need assistance. ### Step 5: Work Through the Rest of the Year Once your breeding and calving dates are set, you can build out the rest of the management calendar. Here is a sample timeline for a spring calving herd: | Month | Management Activity | |---|---| | January | Heifers start calving, watch closely, assist as needed | | February | Main cow herd starts calving, record birth dates and calving ease | | March | Finish calving, turn bulls out with cows that have calved and are ready to breed | | April | Heifer breeding starts, continue calving late cows | | May | Main herd breeding starts, pull bulls at end of breeding season | | June | Pregnancy check cows and heifers, cull open females | | July | Bulls come out of the herd, evaluate bull condition | | August | Wean calves, vaccinate, sort by market readiness | | September | Fall herd health work, [body condition scoring](/knowledge/animal-farming/farm-management/body-condition-scoring-a-tool-for-feed-management) | | October | Pregnancy check again if needed, cull late bred cows | | November | Weaning weights, replacement heifer selection | | December | Plan next year's breeding season, order supplies | This is a simplified version. Your actual calendar will depend on your region and your specific management. The point is that the breeding chart drives the whole year. Once you have your breeding dates set, everything else falls into place. ## Genetic Selection for Your Herd ### Start with a Plan Genetic selection is not about picking the biggest bull in the ring or the one with the flashiest coat. It is about identifying what your herd needs to improve and then choosing genetics that move those traits in the right direction. Before you buy a bull or select replacement heifers, write down your operation's goals. Answer these questions: - What is my primary market for calves? - What traits does that market pay a premium for? - What are the weaknesses in my current cow herd? - What environmental challenges does my operation face? - How much growth can my forage and feed resources support? A herd selling calves to a backgrounder who wants rapid growth needs different genetics than a herd selling replacement females to other commercial producers. A herd on harsh desert range needs different genetics than a herd on lush irrigated pasture. There is no single perfect beef animal. There is only the animal that fits your resources and your market. ### Understanding Expected Progeny Differences Expected Progeny Differences, commonly called EPDs, are the best tool we have for comparing animals for genetic merit. An EPD is a prediction of how future progeny of an animal will perform compared to the progeny of other animals in the same breed. They are expressed in the units of the trait, such as pounds for weaning weight or days for calving interval. The key thing to understand about EPDs is that they are comparisons within a breed, not across breeds. A weaning weight EPD of 50 in one breed does not mean the same thing as a weaning weight EPD of 50 in another breed. You can only compare EPDs between animals of the same breed. Here are the EPDs that matter most for commercial producers: | EPD | What It Predicts | Why It Matters | |---|---|---| | Calving Ease Direct | Percentage of unassisted births from first calf heifers | Reduces calving problems and calf loss | | Calving Ease Maternal | Percentage of unassisted births in a bull's daughters | Identifies bulls whose daughters calve easily | | Birth Weight | Birth weight of progeny | High birth weight can cause calving difficulty | | Weaning Weight | Weight of progeny at weaning | Drives sale weight and profitability | | Yearling Weight | Weight of progeny at yearling age | Important if you retain ownership or sell yearlings | | Milk | Milk production of daughters | Affects calf growth and cow maintenance needs | | Stayability | Probability a bull's daughters stay in the herd | Indicates fertility and longevity | | Docility | Temperament of progeny | Affects safety and handling ease | ### Choosing a Bull Bull selection is the fastest way to change your herd genetically because one bull can sire 25 to 50 calves per year. That is a significant portion of your calf crop. Start your bull selection by identifying the three or four traits that matter most to your operation. Do not try to select for 15 traits at once. You will end up with a bull that is average at everything and excellent at nothing. For a commercial herd selling weaned calves, the priority traits are usually: 1. Calving ease (especially for heifers) 2. Weaning weight 3. Docility 4. Structural soundness For a herd keeping replacement heifers, add: 5. Maternal calving ease 6. Stayability 7. Milk (at a level your forage can support) When you look at a bull catalog, set minimum thresholds for your priority EPDs and then compare bulls that meet those thresholds. Look at the bull's own physical characteristics too. A bull with excellent EPDs but bad feet, poor structure, or a bad disposition is a liability no matter what his numbers say. ### Selecting Replacement Heifers Replacement heifer selection is the other side of genetic progress. While bull selection brings in new genetics, heifer selection determines which genetics stay in your herd. Start with the basics. A replacement heifer should: - Be born early in the calving season - Have a weaning weight above the herd average - Be structurally sound with good feet and legs - Have a sound udder and good teat placement - Come from a cow that breeds early and calves without assistance - Be docile and easy to handle Do not keep heifers just because they are big. A heifer that is too large for her age may be overconditioned, which can hurt her fertility. Do not keep heifers just because they are pretty. Pretty is not a productive trait. Keep heifers that fit your production system and your market. A good rule of thumb is to select 1.5 to 2 times more heifers than you need to replace. That gives you room to cull heifers that fail to breed, fail a pelvic measurement, or develop problems during their first calving. If you need 15 replacements, select 25 to 30 heifers and let the breeding program sort out which ones stay. ### The Value of a Terminal Sire If you keep replacement heifers from your own herd, you have a two breed approach available. Use a maternal bull on your cows to produce replacement heifers, and use a terminal bull on the rest to produce market calves. A maternal bull is selected for traits that make good mothers: calving ease, milk, stayability, and moderate mature size. A terminal bull is selected for growth, carcass quality, and feed efficiency. Terminal calves are all sold, so you do not care about their maternal traits. This approach lets you have the best of both worlds. Your replacement heifers come from genetics selected for maternal ability, and your market calves come from genetics selected for growth and carcass merit. It does require managing two breeding groups, which means more labor and more records, but the payoff can be substantial. ## Bull Management and Breeding Soundness ### The Breeding Soundness Exam Every bull should pass a breeding soundness exam, or BSE, before he is turned out with cows. A BSE is performed by a veterinarian and includes three components: 1. Physical examination 2. Reproductive tract examination 3. Semen evaluation The physical exam checks overall health, feet, legs, eyes, and body condition. The reproductive exam checks the testicles for size, tone, and abnormalities. The semen evaluation checks sperm motility and morphology. A BSE is not a guarantee of fertility. It only tells you that the bull is physically capable of breeding and producing viable semen. But it catches the most common problems before they cost you a breeding season. Have the BSE done 30 to 60 days before the breeding season starts. That gives you time to replace a bull that fails. Do not wait until the week before turnout. ### Bull to Cow Ratio The number of cows a bull can breed depends on his age, condition, and the size of the breeding pasture. As a general rule: | Bull Class | Cows per Bull | |---|---| | Yearling bulls | 10 to 15 | | Two year old bulls | 15 to 25 | | Mature bulls | 25 to 40 | These numbers assume a controlled breeding season and adequate pasture size. In large pastures where bulls have to travel long distances, reduce the cow to bull ratio. In small pastures with good fencing, you can push the numbers slightly higher. If you are breeding heifers, use fewer cows per bull. Heifers are harder to settle than mature cows, and a young bull may need more experience. A mature bull breeding heifers can handle 15 to 20, while a yearling bull breeding heifers should only be asked to cover 10. ### Bull Condition and Nutrition Bulls lose condition during the breeding season. That is normal. But a bull that starts the season in poor condition will lose more weight, have lower libido, and produce poorer quality semen. Aim to have bulls in a body condition score of 5 to 6 at the start of breeding. That means they have some fat cover over their ribs and back but are not overly fat. Overconditioned bulls are sluggish and may have reduced libido. Underconditioned bulls lack the energy reserves to stay active through a long breeding season. During the breeding season, provide bulls with access to good quality forage and clean water. If you are breeding on pasture, the bulls will graze with the cows. After the breeding season, give bulls a recovery period with good nutrition before you turn them out on low quality winter forage. ## Herd Health and the Breeding Season ### Pre Breeding Vaccinations The breeding season is a good time to address herd health, but most of the vaccine work should happen before breeding starts. A healthy cow is more likely to cycle and conceive than a cow fighting off disease. Work with your veterinarian to develop a vaccination program that fits your herd. Common pre breeding vaccinations include: - Leptospirosis and vibriosis (campylobacter), which cause reproductive failure - Infectious bovine rhinotracheitis (IBR), which can cause abortion - Bovine viral diarrhea (BVD), which causes infertility and abortion - Clostridial diseases, which protect against blackleg and related conditions Vaccinate cows 3 to 4 weeks before the breeding season starts. This gives the immune system time to respond and ensures antibody levels are high during the breeding period. ### [Body Condition Scoring](/knowledge/animal-farming/farm-management/body-condition-scoring-a-tool-for-feed-management) Body condition score is the single best indicator of whether a cow will breed back. Cows that are too thin at calving take longer to resume cycling and have lower conception rates. The body condition scoring system runs from 1 to 9, with 1 being emaciated and 9 being extremely fat. For beef cows: | BCS | Description | Breeding Expectation | |---|---|---| | 3 or less | Very thin, prominent bones | Poor chance of breeding back | | 4 | Thin, some fat cover | Reduced conception rates | | 5 | Moderate, fat cover over ribs | Good conception rates | | 6 | Good condition, smooth appearance | Excellent conception rates | | 7 or higher | Fat, heavy fat cover | Reduced fertility, expensive to maintain | Cows should be at a body condition score of 5 or better at calving. If they are thinner than that, they will not cycle early enough to breed back within a 60 to 90 day season. Score your cows at weaning, at mid gestation, and at calving. Use the scores to sort cows into feeding groups. Thin cows get extra feed. Fat cows get less. This targeted feeding is more efficient than feeding the whole herd the same ration. ### Mineral Supplementation Mineral deficiencies can cause silent breeding problems. Cows that look healthy may fail to cycle or conceive if they are deficient in key minerals. The minerals that matter most for reproduction include: - Phosphorus, which is critical for ovulation and conception - Copper, which affects hormone production - Zinc, which supports immune function and reproduction - Selenium, which is involved in fertility and calf health - Manganese, which affects ovulation and calf survival Provide a good quality mineral supplement free choice year round. If you suspect a deficiency, work with your veterinarian to test forage and blood samples. Do not guess at mineral levels. Too much of some minerals can be as harmful as too little. ## Pregnancy Diagnosis and Culling ### When to Pregnancy Check Pregnancy diagnosis is one of the most profitable management practices available to cattle producers. It tells you which cows are bred and which are open, so you can make culling decisions based on facts rather than guesses. The best time to pregnancy check is 30 to 45 days after the bulls are pulled. At that point, the earliest bred cows are 90 to 105 days pregnant and the latest are 30 to 45 days pregnant. A veterinarian can diagnose pregnancy by rectal palpation or ultrasound. Ultrasound has an advantage over palpation because it can also determine the stage of pregnancy and the sex of the fetus. Knowing the stage of pregnancy helps you sort cows into calving groups. Knowing fetal sex can help you market replacement heifers or make bull selection decisions. ### Culling Open Cows Open cows are the most expensive animals in your herd. They eat for a full year and produce nothing. Every open cow should be culled unless she has a very good reason for being open. The culling decision is simple: if a cow is open, she goes to market. Do not give her another chance. The only exception is a young cow that was in poor condition or had a difficult calving. Even then, you need to ask yourself if she is worth the cost of keeping her for another year. Cows that calve late are almost as expensive as open cows. A cow that calves 60 days after the rest of the herd weans a calf that is 60 days younger and 100 to 150 pounds lighter. That is a direct loss of income. Cull late calving cows aggressively. ### The Value of Culling Data Your culling decisions are only as good as your records. If you do not know which cows calve early and which calve late, you cannot make informed culling decisions. Keep these records for every cow in the herd: - Cow identification number - Birth date - Sire and dam - Calving dates for every calf - Calving ease score for every birth - Weaning weight of every calf - Body condition score at key times - Health treatments Use these records to identify your most productive cows and your least productive cows. The most productive cows are the ones you want to keep replacements from. The least productive are the ones that should go to market. ## Common Mistakes in Breeding Season Planning ### Mistake 1: Breeding Season Is Too Long The most common mistake in cow calf operations is leaving the bull in the herd year round or for too long. A 365 day breeding season produces calves every month of the year, which means you cannot manage calving, weaning, or marketing efficiently. If you currently run a long breeding season, do not try to fix it all at once. Pull the bulls for 30 days this year, then 60 days next year, then 90 days the year after. Each year, cull the cows that calve late. Within 3 to 4 years, you can have a tight 60 day calving window. ### Mistake 2: Ignoring Body Condition Many producers expect cows to breed back on poor forage with no supplemental feed. It does not work. Cows that are thin at calving will not cycle early enough to breed back in a controlled season. Score your cows at weaning and again 60 days before calving. If cows are below a body condition score of 5, start supplementing immediately. The cost of feed is almost always less than the cost of an open cow. ### Mistake 3: Buying Bulls Without a Plan A bull purchase is a 2 to 3 year commitment. The bull's genetics will be in your herd for years through his daughters and his sons' daughters. Buying a bull without a clear idea of what you want him to improve is like buying a truck without knowing if you need to haul hay or pull a trailer. Write down your selection criteria before you go to the sale. Set minimum EPD thresholds. Stick to them. Do not let a fancy looking animal with poor numbers talk you out of your plan. ### Mistake 4: Not Pregnancy Checking Skipping pregnancy diagnosis to save money is false economy. The cost of a pregnancy check is small compared to the cost of feeding an open cow through the winter. Pregnancy checking also lets you sort pregnant cows by calving date, which improves your ability to manage nutrition and calving. ### Mistake 5: Keeping Too Many Replacement Heifers Some producers keep every heifer that looks good, which leads to a herd full of young, unproven cows. Keeping too many heifers also means you have to cull more mature cows, which can hurt your herd's genetic base. Keep only the number of heifers you need to maintain your herd size, plus a small buffer for culling. A 20 percent replacement rate is typical for a growing herd. A stable herd needs 15 to 18 percent. ### Mistake 6: Using the Same Bull on Heifers and Cows Heifers need calving ease genetics. Mature cows can handle more birth weight. Using the same bull on both groups means you either risk calving problems in heifers or sacrifice growth in the cow herd. If you cannot run two breeding groups, select a bull with calving ease EPDs that are safe for heifers and accept that you are giving up some growth in mature cow calves. The safety of your heifers is worth more than the extra pounds. ## Monitoring and Record Keeping ### What to Record Good records are the foundation of genetic improvement. You cannot select for traits you do not measure, and you cannot cull accurately without knowing which cows perform best. At minimum, record these items for every cow and calf: | Item | When to Record | Why It Matters | |---|---|---| | Cow ID | At birth or purchase | All records tie back to this number | | Calving date | At each birth | Identifies early and late calvers | | Calving ease score | At each birth | Identifies cows that calve easily | | Calf birth weight | Within 24 hours of birth | Tracks birth weight trends | | Calf sex | At birth | Needed for weaning weight adjustments | | Calf weaning weight | At weaning | The primary measure of productivity | | Cow body condition | At weaning and calving | Identifies nutritional needs | | Breeding dates | When bulls go in and out | Sets the breeding calendar | ### Using Records to Make Decisions Records only have value if you use them. At the end of each year, sit down and analyze your data. Calculate these numbers for your herd: - Calving distribution by month and week - Percentage of cows calving in the first 21 days of the season - Weaning weight average and range - Average calving interval - Percentage of open cows - Replacement heifer pregnancy rate Use these numbers to identify problems. If less than 60 percent of your cows calve in the first 21 days, your breeding season is too long or your cows are in poor condition at breeding. If weaning weights vary by more than 100 pounds within an age group, your calving window is too wide or your genetics are inconsistent. ### The Value of Consistency The biggest mistake producers make with records is changing systems every year. They use a paper notebook one year, a spreadsheet the next, and an app the year after. The records never accumulate enough to be useful. Pick a system and stick with it for at least 5 years. It can be a simple notebook, a spreadsheet, or a commercial herd management software. What matters is that you record the same data the same way every year. Only then can you see trends and make meaningful comparisons. ## When to Call a Veterinarian or Extension Agent Most breeding season management is something you can handle yourself. But there are times when professional help is worth the cost. Call your veterinarian when: - A bull fails his breeding soundness exam and you need a diagnosis - Cows are not cycling even though they are in good condition - Conception rates are below 85 percent in mature cows - You see signs of reproductive disease, such as abortions or retained placentas - A cow has a difficult calving and you cannot resolve it safely - You are unsure about pregnancy diagnosis results - You need help designing a vaccination program Call your extension agent when: - You want to set up a record keeping system and need advice - You are considering changing your breeding season dates - You want help interpreting EPDs and bull catalogs - You are developing a replacement heifer selection program - You need help analyzing your herd's reproductive data - You are considering a new breed or crossbreeding system Both your veterinarian and your extension agent are resources you have already paid for through your taxes and your veterinary fees. Use them. The extension service can also help you connect with local producer groups, bull test stations, and heifer development programs. These are excellent ways to learn from other producers and to find genetics that are proven in your area. ## Frequently Asked Questions ### How long should I leave the bull in with the cows? For a controlled breeding season, 60 to 90 days is the standard recommendation. A 60 day season produces a more uniform calf crop and makes calving management easier. A 90 day season gives cows more chances to conceive and is a good starting point if you are tightening up from a longer season. If you are just starting to control your breeding season, begin with 90 days and reduce the window by 15 days every couple of years as your herd fertility improves. ### What is the ideal calving interval for beef cows? The ideal calving interval is 365 days. That means a cow calves at the same time every year. To achieve this, a cow must conceive within 82 days of calving, since gestation averages 283 days. Cows that calve early in the season and are in good body condition should be able to breed back within that window. Cows that calve late or are in poor condition will have longer intervals and should be culled. ### How do I know if my bull is fertile? A breeding soundness exam performed by a veterinarian is the best way to know if a bull is fertile. The exam includes a physical examination, a reproductive tract examination, and a semen evaluation. Have the exam done 30 to 60 days before the breeding season so you have time to replace a bull that fails. A BSE is not a guarantee of fertility, but it catches the most common problems. ### When is the best time to pregnancy check cows? The best time is 30 to 45 days after the bulls are removed from the herd. At that point, the earliest bred cows are 90 to 105 days pregnant and the latest are 30 to 45 days pregnant. A veterinarian can diagnose pregnancy by rectal palpation or ultrasound. Ultrasound also tells you the stage of pregnancy, which helps you sort cows into calving groups. ### How many cows can one bull breed? A mature bull in good condition can breed 25 to 40 cows in a controlled season. A two year old bull should be limited to 15 to 25 cows. A yearling bull should only be asked to breed 10 to 15 cows. Reduce these numbers if the breeding pasture is large or rough, or if you are breeding heifers. Heifers are harder to settle than mature cows. ### Should I breed heifers before or after the cow herd? Breed heifers 3 weeks before the mature cow herd. This gives first calf heifers extra time to resume cycling after calving before their second breeding. It also means heifers calve earlier in the season, which gives them a longer recovery window. You can also watch heifers more closely during calving because they calve before the main rush starts. ### What body condition score do cows need to breed back? Cows should be at a body condition score of 5 or better at calving to breed back reliably within a controlled season. A BCS of 5 means the cow has moderate fat cover over her ribs and back. Cows at a BCS of 4 or lower will take longer to resume cycling and will have lower conception rates. Score your cows at weaning and 60 days before calving so you have time to add condition before breeding. ### How do I select a bull for my heifers? Select a bull with a calving ease direct EPD that is well above the breed average and a birth weight EPD that is below breed average. Look for a bull with a documented history of unassisted births in his progeny. The bull should also have good maternal calving ease EPDs if you plan to keep replacement heifers from his daughters. Do not use a high growth bull on heifers just because he has impressive weaning weights. ## Related Farming Guides The following guides provide additional information on cattle management, herd health, and reproductive planning. They will be populated here based on the topics you are currently exploring. ## Related Clinical & Scientific Guides * [Cattle Head Gate Selection and Adjustment](/knowledge/animal-farming/beef-cattle/cattle-head-gate-selection-and-adjustment) * [Beef Cattle Handling Facility Flow](/knowledge/animal-farming/beef-cattle/beef-cattle-handling-facility-flow) * [Beef Cattle Maternity Pen Design: Comfort and Monitoring](/knowledge/animal-farming/beef-cattle/beef-cattle-maternity-pen-design-comfort-monitoring) ## 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.