Feed Testing for Beef Cattle: Sampling and Interpretation

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

Key Takeaways

• Accurate feed testing for beef cattle necessitates proper sampling techniques, including using a core probe for hay (collecting 10-20 cores per lot) and sampling silage at feedout time to reflect actual nutrient content.
• Critical feed test parameters for ration balancing include dry matter (DM), crude protein (CP), energy (TDN, NEm, NEg), fiber fractions (ADF, NDF), and key minerals (Ca, P, Mg).
• Nitrate testing is essential for annual forages (e.g., sorghum, millet, cornstalks) due to potential accumulation, with levels above 1.0% DM requiring dietary limitations for pregnant cattle and levels above 1.5% DM being toxic.
• Feed test results must be compared against specific animal requirements (e.g., dry vs. lactating cows, growing calves) to identify deficiencies and guide cost-effective supplementation strategies, preventing metabolic disorders like grass tetany.
• Re-testing stored feeds (after 6 months) and monitoring body condition scores are crucial for adjusting feeding programs as nutrient levels decline or animal performance indicates discrepancies between predicted and actual intake.

Every beef producer knows that feed is the largest variable cost in the cow herd, yet many make feeding decisions based on guesswork. Hay that looks good can be lower in protein than expected, and silage that smells fine can have mold issues that reduce intake. Feed testing for beef cattle removes the guesswork and lets you match supplements to what your forage actually provides. This article explains how to sample hay, silage, and other feeds correctly, how to read a lab report, and how to use those numbers to build a cost-effective feeding program. It is written for cow-calf operators, stocker operators, and anyone who buys or grows feed for beef cattle.

At a Glance

• Test every new cutting or lot of hay before feeding it to cattle.
• Sample hay with a core probe, not by hand grabbing flakes.
• Collect at least 10 to 20 cores per lot and combine them into one sample bag.
• For haylage and silage, sample at feedout time, not at harvest, for the most accurate ration balancing.
• Key numbers on a feed test report are dry matter, crude protein, energy as TDN or NEm and NEg, ADF, NDF, and minerals like calcium, phosphorus, and magnesium.
• Nitrate testing is essential for annual forages like sorghum, sudan, millet, and cornstalks, especially after drought or heavy nitrogen fertilization.
• Re-test feeds that have been stored for more than six months, as nutrient levels decline over time.
• Use feed test results to avoid overpaying for supplements and to prevent metabolic problems like grass tetany and milk fever.

Why Feed Testing Matters for Beef Cattle

Feed testing for beef cattle is not a lab exercise for large operations alone. It is a management tool that pays for itself many times over in most herds. The cost of a standard forage analysis is small compared to the cost of overfeeding protein or underfeeding energy for an entire winter.

Consider a simple example. A producer feeds 100 cows for 150 days. If the hay tests 8 percent crude protein instead of the assumed 12 percent, the herd is short on protein for the entire winter. Cows lose body condition, breed back later, and wean lighter calves. The lost revenue from a delayed breeding season and lighter weaning weights far exceeds the cost of a feed test. On the other side, if hay tests higher than expected, the producer can reduce or eliminate expensive supplements and save money without hurting performance.

Feed testing also helps you identify problems before they become clinical. High nitrate forages can cause acute poisoning or chronic poor performance. Low magnesium in lush spring grass can trigger grass tetany. High sulfur in water or feed can cause polioencephalomalacia, a brain disease that is often fatal. A feed test flags these risks so you can adjust the ration or the supplement program before cattle show signs of trouble.

Finally, feed testing supports better buying decisions. When you purchase hay by the bale or by the ton, a test report tells you what you are actually paying for. Two loads of hay can look identical but differ by 30 percent in energy value. The cheaper load may be the more expensive feed per unit of energy once you account for lower quality.

How to Sample Hay for Testing

The accuracy of a feed test depends almost entirely on the quality of the sample. A lab can only analyze what you send. A poor sample gives misleading results, and those misleading results lead to poor feeding decisions. Sampling hay correctly is simple but requires attention to detail.

Gather the Right Equipment

You need a hay probe, sometimes called a core sampler, that attaches to a drill. Probes are available from agricultural supply companies, extension offices, and some feed labs. A standard probe is 12 to 24 inches long with a cutting tip that removes a core from the bale. The probe should be sharp so it cuts cleanly through the bale rather than crushing the hay.

You also need clean plastic buckets or bags for collecting cores, a permanent marker for labeling, and a sturdy shipping box or padded envelope for sending the sample to the lab. Do not use cloth bags, paper bags, or anything that could contaminate the sample or allow moisture to escape.

Sample Each Lot Separately

A lot is a group of hay that came from the same field, was cut at the same time, and was stored under the same conditions. Hay from different fields, different cuttings, or different storage locations should be sampled separately. Mixing cores from different lots into one sample gives you an average that matches nothing you actually feed.

If you have 200 bales of first-cutting alfalfa and 150 bales of second-cutting grass hay, those are two separate lots. Sample and test each one. If you bought hay from two different sellers, even if it looks similar, treat them as separate lots until you have test results that show they are similar.

Take Cores from Multiple Bales

Collect cores from at least 10 to 20 bales per lot. For small square bales, take one core from each of 10 to 20 bales. For large round bales, take two cores from each of 10 bales, or one core from each of 20 bales. For large square bales, take two to three cores from each of 10 to 15 bales.

The exact number depends on the variability within the lot. If the hay looks inconsistent, with some bales green and leafy and others brown and stemmy, sample more bales. The goal is to capture the average quality of the lot, not the best bale or the worst bale.

Probe in the Right Locations

For large round bales, insert the probe horizontally into the side of the bale, about halfway between the center and the outer edge. Avoid the outer weathered layer and avoid the very center, which may have different moisture content. For large square bales, probe from the end or the side, again avoiding the outer layer.

For small square bales, probe from the end of the bale through the flakes. This gives you a sample that includes material from multiple flakes within the bale.

Combine and Mix the Cores

Place all cores from the same lot into a single clean plastic bucket. Break up the cores by hand and mix them thoroughly. Fill the sample bag about two-thirds full, which is roughly one to two cups of material. Do not pack the bag tightly, as the lab needs to dry the sample for analysis.

Label and Ship Promptly

Write the lot identification clearly on the bag with a permanent marker. Include the date of sampling, the type of forage, the field or source, and any other information that will help you match results to the correct lot. Complete the submission form that comes with the sample kit and include it with the shipment.

Send the sample to the lab immediately. If you cannot ship it the same day, refrigerate it. Do not leave samples in a hot truck or in direct sunlight, as heat can change the nutrient content before the lab analyzes it.

How to Sample Silage and Haylage

Silage and haylage require different sampling methods because the forage is fermented and the moisture content is high. The best time to sample fermented feeds is at feedout, not at harvest. Nutrient values change during fermentation, and the values you need for ration balancing are the values of what you are actually feeding today.

Sample at Feedout

Collect samples from the face of the silo, bunker, or bag as you feed. Take a handful of silage from several different locations across the face, going from top to bottom. Combine these into one sample and mix well.

For silage bags, take samples from several different bags if you are feeding from multiple bags. For bunker silos, sample from different depths and different areas of the face. The goal is to capture the average of what the cattle are eating over the course of a week or two.

Do Not Rely on Harvest Samples

Many producers send samples at harvest time to guide the ensiling process. Those samples are useful for checking moisture and fermentation, but they do not tell you the final nutrient content. Fermentation consumes sugars and changes the protein fractions. The feed test you use for ration balancing should come from feedout samples.

Handle Wet Samples Properly

Silage samples are wet and can spoil quickly. Place them in a sealed plastic bag and refrigerate immediately. Ship them to the lab in a cooler with ice packs if the weather is warm. Do not let silage samples sit at room temperature for more than a few hours, as the nutrients will change.

Test More Frequently for Silage

Silage quality changes as you move through the storage structure. The top of a bunker may be more spoiled than the middle. The ends of a bag may have more air exposure. Plan to test silage every two to four weeks during the feeding period, or whenever you notice a visible change in color, smell, or texture.

How to Sample Other Feeds

Grain, byproducts, and total mixed rations require their own sampling protocols.

Grain and Concentrates

Sample grain from multiple bags, bins, or truckloads. Use a grain probe to collect samples from different depths if the grain is stored in a bin. Combine the samples, mix well, and send about one to two cups to the lab.

Byproducts

Byproducts like distillers grains, corn gluten feed, soybean hulls, and cottonseed can vary significantly between loads. Sample every new load or every delivery if you buy by the truckload. Mix the sample well before bagging, as byproducts can separate during transport.

Total Mixed Rations

Sample a TMR at the feed bunk, not at the mixer. Collect samples from several locations along the bunk immediately after feeding. Combine and mix the samples, then send about two cups to the lab. TMR samples are useful for checking whether the ration you formulated is actually the ration the cattle receive.

Understanding the Feed Test Report

Feed test reports can look intimidating with columns of numbers and abbreviations. In practice, you only need to focus on a handful of values to make good feeding decisions. The most important values are dry matter, crude protein, energy, fiber fractions, and key minerals.

Dry Matter

Dry matter is the percentage of the feed that is not water. Hay typically runs 88 to 92 percent dry matter. Silage runs 30 to 45 percent dry matter. Grain runs 85 to 90 percent dry matter.

Dry matter matters for two reasons. First, it tells you how much water you are paying for when you buy feed. Second, it is the basis for all other nutrient values. A feed test reports protein and energy on a dry matter basis, which means the values are corrected for moisture content. When you build a ration, you convert these values back to an as-fed basis to know how many pounds to feed.

Crude Protein

Crude protein is an estimate of the total protein in the feed, calculated from the nitrogen content. It is reported as a percentage of dry matter. For beef cattle, crude protein is the main value used to determine whether you need protein supplementation.

Typical crude protein values for common feeds are:

• Grass hay: 6 to 12 percent
• Alfalfa hay: 15 to 22 percent
• Corn silage: 7 to 9 percent
• Corn grain: 8 to 10 percent
• Distillers grains: 28 to 32 percent
• Soybean meal: 46 to 50 percent

The protein requirement for a mature beef cow in mid-gestation is about 7 to 8 percent crude protein in the total diet. A lactating cow needs 10 to 12 percent. Growing calves and stockers need 12 to 14 percent depending on target gain.

Energy Values

Energy is reported in several ways. The most common are TDN (total digestible nutrients), NEm (net energy for maintenance), NEg (net energy for gain), and sometimes DE (digestible energy) or ME (metabolizable energy).

TDN is the simplest value to understand. It is the sum of digestible fiber, protein, fat, and carbohydrate in the feed, expressed as a percentage of dry matter. Grass hay typically runs 50 to 60 percent TDN. Alfalfa hay runs 55 to 65 percent. Corn silage runs 65 to 72 percent. Corn grain runs 85 to 90 percent.

NEm and NEg are more precise for ration balancing because they account for the efficiency of energy use for maintenance versus gain. NEm is used to meet the cow's maintenance needs. NEg is used for growing animals and for weight gain. A mature cow in mid-gestation needs about 0.45 to 0.55 Mcal per pound of dry matter for maintenance. A lactating cow needs 0.60 to 0.70 Mcal per pound.

Fiber Fractions

ADF (acid detergent fiber) and NDF (neutral detergent fiber) are the two fiber values you will see on most reports.

ADF is the least digestible fiber fraction. It is inversely related to energy. As ADF goes up, energy goes down. Grass hay with an ADF of 40 percent has less energy than grass hay with an ADF of 32 percent.

NDF is the total fiber content, including both digestible and indigestible fiber. NDF is related to intake. As NDF goes up, cattle can eat less of the feed because it fills the rumen faster. High-quality forages have NDF values in the 40 to 50 percent range. Low-quality forages can exceed 60 percent NDF.

For mature beef cows, the total diet should contain about 30 to 35 percent NDF on a dry matter basis to maintain rumen function. Forages with NDF above 60 percent are often too low in energy for lactating cows unless supplemented.

Minerals

Most standard feed tests include calcium, phosphorus, magnesium, and potassium. Some include sulfur, sodium, iron, manganese, copper, zinc, and molybdenum.

Calcium and phosphorus are the two minerals most often considered in beef rations. The ideal calcium to phosphorus ratio is about 2 to 1. Legume hays like alfalfa are high in calcium and low in phosphorus. Grain and byproducts are higher in phosphorus. A feed test tells you whether your forage base provides adequate calcium and whether you need to add phosphorus.

Magnesium is important for preventing grass tetany. Lush spring grass and small grains can be low in magnesium and high in potassium, which interferes with magnesium absorption. If your forage test shows magnesium below 0.20 percent and potassium above 2.5 percent, cattle are at risk for grass tetany.

Nitrates

Nitrate testing is a separate analysis that should be run on annual forages, especially after drought, frost, or heavy nitrogen fertilization. Nitrate accumulates in the lower part of the plant and can cause poisoning when cattle consume high levels.

Nitrate levels in forage are interpreted as follows:

• Below 0.5 percent nitrate on a dry matter basis: safe for all cattle
• 0.5 to 1.0 percent: safe for non-pregnant cattle, but limit for pregnant cows
• 1.0 to 1.5 percent: limit to 50 percent of the diet for non-pregnant cattle
• Above 1.5 percent: toxic, do not feed free choice

High nitrate forages can be diluted with other feeds to reduce the risk, but the dilution must be calculated carefully. When in doubt, call your veterinarian or extension agent before feeding suspect forage.

How to Interpret Feed Test Results for Your Herd

A feed test report gives you numbers, but the numbers only matter if you can translate them into feeding decisions. Here is a step-by-step approach to using feed test results in your operation.

Step One: Compare to the Animal's Requirements

Start with the class of cattle you are feeding. A dry pregnant cow in the second trimester has modest requirements. A lactating cow in the first 90 days after calving has the highest requirements of any animal in the herd. Growing calves and stockers need high energy for gain.

Use the table below as a general guide for mature beef cows. These values are on a dry matter basis.

Compare your feed test values to these requirements. If your hay tests 8 percent crude protein and 55 percent TDN, it meets the needs of a dry cow in mid-gestation but falls short for a lactating cow. You will need to supplement protein, energy, or both depending on the class of cattle.

Step Two: Determine What to Supplement

If the forage is deficient in protein, you have several options. Alfalfa hay can be fed as a protein supplement at 3 to 5 pounds per head per day. Commercial protein blocks or tubs are convenient but more expensive per unit of protein. Urea can be added to the ration for cattle consuming adequate energy, but it should not exceed 0.1 percent of the diet dry matter and must be fed with a slowly fermentable energy source.

If the forage is deficient in energy but adequate in protein, you need an energy supplement. Corn grain, distillers grains, soybean hulls, and corn gluten feed are common options. Distillers grains are a good choice because they provide both energy and protein. Soybean hulls are high in digestible fiber and work well with low-quality forages because they do not disrupt fiber digestion the way starch does.

If both protein and energy are low, which is common with mature grass hay, you may need a combination supplement. A common recommendation is 3 to 5 pounds of distillers grains or a 30 percent protein cube per cow per day. The exact amount depends on the severity of the deficiency and the cow's stage of production.

Step Three: Account for Intake

Cattle eat a percentage of their body weight in dry matter. A mature cow eats about 2.0 to 2.5 percent of her body weight in dry matter per day. A 1,300 pound cow eats about 26 to 32 pounds of dry matter per day. A growing calf eats about 2.5 to 3.0 percent of body weight.

Feed test values are on a dry matter basis, so you need to convert to as-fed weights to know how many pounds to feed. The formula is:

As-fed pounds = Dry matter pounds / Dry matter percentage

If you want to feed 30 pounds of dry matter from hay that is 90 percent dry matter, you need to feed 33.3 pounds as-fed. If the hay is 85 percent dry matter, you need 35.3 pounds as-fed.

Step Four: Monitor Body Condition

Feed tests are a tool, but the cow is the final judge. Body condition scoring is the most reliable way to check whether your feeding program is working. Score cows on a 1 to 9 scale, with 1 being emaciated and 9 being obese. A mature cow should be at a body condition score of 5 at calving. Cows that calve at a score of 4 or lower have longer postpartum intervals and lower conception rates.

Body condition scoring should be done at key times: at weaning, at mid-gestation, at calving, and at the start of breeding. If cows are losing condition despite what the feed test says, re-check your sampling technique and your intake estimates. The feed test may be correct, but the cows may not be eating what you think they are eating.

Common Mistakes in Feed Testing

Feed testing is simple, but mistakes are common. Here are the errors that cause the most problems in beef operations.

Sampling Only the Best Bales

Some producers pick out the best-looking bale in the lot and sample that one. This gives a false sense of quality. The sample must represent the average of the lot, not the best or the worst. If you cannot sample 10 to 20 bales, at least sample several that look different from each other.

Grabbing a Handful of Hay

Hand-grabbed samples are biased toward the leaves and fine material that come off easily. These are usually higher in protein and lower in fiber than the bale as a whole. The result is that the test overestimates quality and the ration is deficient. Always use a core probe.

Testing Only One Lot of Hay

If you have multiple cuttings or multiple fields, test each one. A single test on one lot tells you nothing about the other lots. The cost of testing is small compared to the cost of a feeding mistake that lasts all winter.

Ignoring Dry Matter

When you compare feed test values to animal requirements, make sure both are on the same basis. Feed test reports are on a dry matter basis. Animal requirements are also on a dry matter basis. But when you calculate how many pounds to feed, you must convert to as-fed. Failing to do this conversion leads to overfeeding or underfeeding.

Not Re-testing Stored Feeds

Hay that is stored for many months loses vitamins and some energy. Silage continues to ferment and change. A feed test from last fall may not describe the feed you are feeding in February. Re-test stored feeds every few months, especially if you see changes in color, smell, or animal performance.

Sampling Wet Feeds Incorrectly

Wet samples like silage and haylage must be handled carefully. They can heat and spoil between sampling and shipping. Refrigerate samples and ship them quickly. Do not leave them in a mailbox or truck overnight.

Forgetting Nitrate Testing

Annual forages like sorghum, sudan, millet, cornstalks, and even some weeds can accumulate nitrates. Drought stress, frost, and high nitrogen fertilization increase nitrate accumulation. If you feed any of these forages, test for nitrates before feeding, especially if the forage was stressed.

Decision Thresholds for Common Feed Test Results

Knowing when to act on a feed test result is as important as knowing how to sample. Here are practical thresholds for common situations.

Protein Thresholds

• Forage below 7 percent crude protein: Protein supplementation is required for all classes of beef cattle, including dry cows.
• Forage at 7 to 9 percent crude protein: Dry cows may be adequate, but lactating cows need protein supplement.
• Forage above 10 percent crude protein: Most classes of cattle meet protein needs from forage alone, provided intake is adequate.

Energy Thresholds

• Forage below 50 percent TDN: Energy supplementation is needed for dry cows in late gestation and for all lactating cows.
• Forage at 50 to 55 percent TDN: Dry cows may be adequate in mid-gestation, but lactating cows need energy supplement.
• Forage above 58 percent TDN: Most mature cows meet energy needs from forage alone.

Fiber Thresholds

• NDF above 60 percent: Intake will be limited. Cattle may not consume enough dry matter to meet energy needs even if the forage appears adequate on paper.
• ADF above 42 percent: Energy is likely limiting. Supplement with an energy source like grain, distillers grains, or soybean hulls.

Nitrate Thresholds

• Below 0.5 percent: Safe for all cattle.
• 0.5 to 1.0 percent: Safe for non-pregnant cattle. Limit for pregnant cows.
• 1.0 to 1.5 percent: Limit to 50 percent of the diet. Dilute with other feeds.
• Above 1.5 percent: Do not feed free choice. Call your veterinarian or extension agent.

Mineral Thresholds

• Calcium below 0.20 percent and phosphorus below 0.15 percent in the total diet: Mineral supplementation is needed.
• Magnesium below 0.20 percent in lush spring forage: Grass tetany risk is high. Feed high-magnesium mineral.
• Sulfur above 0.40 percent in the total diet: Risk of polioencephalomalacia. Check water sulfur levels too.
• Molybdenum above 5 ppm with low copper: Risk of copper deficiency. Work with a veterinarian to balance copper and molybdenum.

Monitoring and Recordkeeping

Feed testing is not a one-time event. It is part of a monitoring system that helps you adjust your feeding program as conditions change.

Keep a Feed Test Log

Record the results of every feed test in a notebook or spreadsheet. Include the date, the lot identification, the forage type, the field or source, and all the key nutrient values. Over time, this log tells you which fields produce the best hay, which cuttings are most consistent, and how storage affects quality.

Track Body Condition Scores

Body condition scores at weaning, mid-gestation, calving, and breeding are the most practical way to evaluate your feeding program. Write them down for each cow or at least for a sample of 20 to 30 cows. If cows are losing condition between weaning and calving, your feed test results or your intake estimates are wrong somewhere.

Track Hay Inventories

Know how many tons of hay you have and how many tons you need. Multiply the number of cows by the average daily dry matter intake by the number of days you expect to feed hay. Add 10 to 15 percent for waste. Compare this to your hay inventory. If you are short, you need to know before the last hay is gone, not after.

Track Supplement Costs

Feed testing lets you buy supplements based on what you actually need rather than what you assume you need. Track the cost per pound of protein and per pound of energy for each supplement you buy. This allows you to compare options on a nutrient basis rather than a per-ton basis.

Re-test at Key Intervals

Test new hay when it is first fed. Test stored hay again after three to six months. Test silage every two to four weeks during feedout. Test any new load of purchased hay before feeding it. These intervals catch changes before they cause performance problems.

When to Call a Veterinarian or Extension Agent

Most feed testing decisions can be handled by the producer with a little training. Some situations require professional help.

Call a Veterinarian When

• Cattle show signs of nitrate poisoning: labored breathing, weakness, dark mucous membranes, sudden death.
• Cattle show signs of grass tetany: muscle twitching, staggering, convulsions, down cows.
• Cattle show signs of polioencephalomalacia: blindness, head pressing, circling, recumbency.
• Cows are calving in poor body condition despite a feed test that says the ration is adequate.
• Multiple cows are down or lethargic and you cannot identify the cause.

Call an Extension Agent When

• You need help interpreting a feed test report and building a supplement program.
• You are considering buying new feed ingredients or byproducts and want to know their feeding value.
• You need help calculating a least-cost ration.
• You want to compare the cost of different supplement options.
• You are planning a forage program and want to know which varieties or cutting schedules produce the best quality feed for your herd.

Extension agents have access to ration balancing software and local data on feed prices and forage quality. They can help you turn a feed test report into a practical feeding plan.

Frequently Asked Questions

How often should I test my hay?

Test every new lot of hay before feeding it to cattle. A lot is hay from the same field, cut at the same time, and stored the same way. If you feed hay for six months from a single lot, one test at the start of feeding is usually enough. If you store hay longer than six months, re-test it because nutrient levels decline over time. For silage, test every two to four weeks during feedout because quality changes as you move through the storage structure.

Can I test hay without a core probe?

You can, but the results will be less reliable. Hand-grabbed samples are biased toward leaves and fine particles, which are higher in protein and lower in fiber than the bale as a whole. This means the test will overestimate quality and your ration will be deficient. A core probe is inexpensive and pays for itself in the first season. If you cannot buy a probe, check with your local extension office or feed lab, as many loan or rent probes to producers.

What is the difference between ADF and NDF?

ADF is acid detergent fiber, the least digestible fiber fraction. It is used to estimate energy content. As ADF goes up, energy goes down. NDF is neutral detergent fiber, the total fiber content including both digestible and indigestible fiber. It is used to estimate intake potential. As NDF goes up, cattle can eat less because the feed fills the rumen faster. Both values are useful, but they tell you different things about the forage.

My hay tests 6 percent protein. Is that safe to feed?

It is safe to feed if you supplement protein. A mature dry cow in mid-gestation needs about 7 to 8 percent crude protein in the total diet. If your hay is 6 percent protein, you need to add a protein supplement. Options include alfalfa hay at 3 to 5 pounds per head per day, commercial protein cubes, or distillers grains. A lactating cow needs more protein, around 10 to 12 percent, so the supplement rate must be higher. Work with your extension agent to calculate the right amount.

What does TDN mean on a feed test?

TDN stands for total digestible nutrients. It is a measure of the energy in the feed, expressed as a percentage of dry matter. It is the sum of digestible fiber, protein, fat, and carbohydrate. Grass hay typically runs 50 to 60 percent TDN. Corn silage runs 65 to 72 percent. Corn grain runs 85 to 90 percent. TDN is a simple way to compare the energy value of different feeds.

Should I test for nitrates?

Test for nitrates if you feed annual forages like sorghum, sudan, millet, cornstalks, or small grains. Nitrates accumulate in these plants when they are stressed by drought, frost, or high nitrogen fertilization. Nitrate levels above 1.0 percent on a dry matter basis are dangerous, and levels above 1.5 percent can be fatal. If you are not sure whether your forage needs a nitrate test, ask your extension agent.

How many cores should I take from a lot of hay?

Take at least 10 to 20 cores per lot. For large round bales, take two cores from each of 10 bales or one core from each of 20 bales. For large square bales, take two to three cores from each of 10 to 15 bales. For small square bales, take one core from each of 10 to 20 bales. If the hay looks inconsistent, sample more bales to get a representative average.

How do I know if my mineral program is adequate?

A feed test gives you the mineral content of your forage. Compare those values to the requirements for your class of cattle. The most important minerals are calcium, phosphorus, magnesium, and sulfur. If your forage is low in calcium or phosphorus, provide a mineral supplement that corrects the imbalance. If magnesium is below 0.20 percent in lush spring forage, feed a high-magnesium mineral to prevent grass tetany. Work with your veterinarian to design a mineral program based on your feed test results.

Related Farming Guides

This section will be populated with links to related farming guides on cattle nutrition, forage management, and herd health. Check back for updates.

Related Clinical & Scientific Guides

• Cattle Head Gate Selection and Adjustment
• Beef Cattle Handling Facility Flow
• Beef Cattle Maternity Pen Design: Comfort and 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.