Ration Formulation for Dairy Cows: Balancing Energy and Protein

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

Key Takeaways

Balancing energy (measured as NEL) and protein (CP) is critical; insufficient energy with high protein leads to wasted protein converted to urea, while insufficient protein limits milk production due to amino acid deficiency.
Dry Matter Intake (DMI) is the primary driver of ration success; accurate measurement (feed offered minus refusals) is essential for balancing diets and detecting early signs of herd health or management issues.
Forage testing (DM, CP, NDF, ADF, energy) for each new lot is foundational, as nutrient content varies significantly with harvest conditions, maturity, and storage, directly impacting diet formulation.
Total Mixed Rations (TMRs) are crucial for consistent nutrient delivery, preventing sorting and ensuring each cow receives the intended diet, with proper mixing time and particle size (e.g., 2-8% on top screen of Penn State Separator) vital for rumen health.
Monitoring key indicators like milk components (fat, protein, MUN), body condition scores (BCS), manure consistency, and feed refusals allows for timely ration adjustments and proactive herd health management.
Sudden ration changes must be avoided; introduce new feeds gradually over 7-10 days to allow rumen microbial adaptation and prevent digestive upsets, off-feed events, and production drops.

Feed costs represent the largest single expense on most dairy operations, often consuming 45 to 60 percent of total production costs. Getting the ration right is not just about keeping feed costs down. It is about matching what you feed to what each group of cows needs for maintenance, milk production, growth, and reproduction. This article explains how to balance dairy cow diets with a focus on the energy and protein relationship, how to build a total mixed ration, and how to monitor whether your feeding program is working. It is written for dairy farmers, herd managers, and farm employees who want a practical, step-by-step approach to ration formulation without needing a degree in animal nutrition.

At a Glance

Energy and protein must be balanced together. Feeding extra protein without enough energy wastes money and can harm milk production and reprod performance.
A total mixed ration (TMR) is the most reliable way to deliver a consistent diet to a group of cows. It prevents sorting and helps every cow eat the same meal.
Dry matter intake (DMI) drives everything. You cannot balance a ration on paper if you do not know how much your cows actually eat.
Test your forages. Hay, silage, and haylage vary in nutrient content from load to load and field to field. Feed values change with storage time and weather.
Work with a nutritionist or extension agent to set up your baseline ration, then use cow body condition scores, milk components, and manure consistency to check your progress.
Introduce ration changes gradually over 7 to 10 days to reduce the risk of rumen upset and off-feed events.
Keep records of feed deliveries, refusals, forage test results, milk production, and body condition scores. These records help you and your adviser spot problems early.
Call a veterinarian if you see a sudden drop in feed intake, multiple cows off feed, or signs of acidosis, ketosis, or milk fever that do not respond to your usual corrective steps.

Understanding Dairy Cattle Nutrition Requirements

A dairy cow is a biological factory. She takes in feed, ferments it in her rumen, and converts it into milk, body tissue, and waste products. To keep that factory running efficiently, you need to supply the right amounts of energy, protein, fiber, minerals, vitamins, and water. This article focuses on energy and protein because these two fractions make up the bulk of the diet and have the largest effect on milk production and herd health.

Energy is measured in megacalories (Mcal) of net energy for lactation (NEL) in the United States system, or in megajoules (MJ) of metabolizable energy in many other countries. The energy in a feed comes from carbohydrates, fats, and to a lesser extent protein. Forage quality determines how much energy your cows can get from the base of the diet. Corn silage, alfalfa hay, and high-quality pasture all provide different energy levels, and those levels change with maturity at harvest and storage conditions.

Protein is measured as crude protein (CP), which is the total nitrogen content of the feed multiplied by 6.25. But not all protein is the same. Rumen-degradable protein (RDP) is broken down by microbes in the rumen to make microbial protein, which becomes the main protein source for the cow. Rumen-undegradable protein (RUP), also called bypass protein, escapes rumen breakdown and is digested in the small intestine. A good ration supplies both fractions in the right proportions.

The energy protein ratio matters because the rumen microbes need energy to convert protein into microbial protein. If you feed high protein and low energy, the microbes cannot use all the protein. Some of it is converted to urea in the liver and excreted in milk and urine. That is wasted money and added environmental load. If you feed high energy and low protein, milk production will be limited because the cow does not have enough amino acids to make milk protein.

The Role of Dry Matter Intake

Before you can balance a ration, you need to know how much your cows eat. Dry matter intake is the weight of feed consumed after removing water. Cows eat to meet their energy needs, but intake is limited by rumen fill, diet digestibility, and physical factors like heat stress and overcrowding.

A mature Holstein cow producing 80 to 100 pounds of milk per day typically eats 50 to 60 pounds of dry matter per day. Jerseys and other smaller breeds eat less in absolute terms but often eat more relative to their body weight. Intake varies with stage of lactation, body condition, ambient temperature, and feed quality.

You can measure dry matter intake on your farm by weighing the feed offered to a group and subtracting the weight of refusals the next day. Multiply the as-fed weight by the dry matter percentage of the ration to get dry matter intake. For example, if you feed 1,000 pounds of a TMR that is 50 percent dry matter and the cows leave 100 pounds of refusals, the group consumed 900 pounds as fed, which equals 450 pounds of dry matter. Divide by the number of cows in the group to get per-cow intake.

Do this for each feeding group at least once a week. Intake changes with weather, feed changes, and cow health. A sudden drop in intake is often the first sign of a problem, whether it is a feed quality issue, a health issue, or a management issue like overcrowding at the bunk.

Forage Testing and Feed Analysis

You cannot balance what you do not measure. Forage testing is the foundation of any ration formulation program. A basic forage analysis includes dry matter, crude protein, neutral detergent fiber (NDF), acid detergent fiber (ADF), and estimated energy values. More detailed tests add minerals, starch, sugar, and sometimes amino acid profiles.

Take forage samples correctly. Use a core sampler for baled hay and haylage. Take cores from at least 10 to 15 bales per lot and combine them into one sample. For silage from a bunker or pile, sample from the face after you have removed spoiled material. Collect small handfuls from multiple points across the face and mix them in a clean bucket. Put the sample in a sealed plastic bag, label it clearly, and send it to a forage testing laboratory.

Test each new load or cutting. Forages change with weather at harvest, soil fertility, and storage conditions. A first cutting alfalfa may test very differently from a second cutting. Corn silage varies by hybrid, maturity at harvest, and kernel processing. Do not assume last year's test results still apply.

Send samples to a certified forage testing lab. Your nutritionist or extension agent can help you interpret the results and enter the values into your ration balancing software. Most labs provide recommendations on sampling technique and can supply sample bags and submission forms.

Energy Sources for Dairy Cows

Energy comes from the carbohydrate and fat fractions of the diet. Carbohydrates are divided into structural carbohydrates, which include fiber, and nonstructural carbohydrates, which include starch and sugars.

Forages provide the fiber base of the diet. Fiber is essential for rumen health because it stimulates chewing, saliva production, and rumen motility. But fiber is also less digestible than starch and sugar, so high-fiber diets limit energy intake. The key is to provide enough effective fiber to keep the rumen healthy without filling the cow up before she meets her energy needs.

Corn silage is the primary energy forage on many dairy farms. It provides starch plus digestible fiber. The starch in corn silage is fermented in the rumen to produce volatile fatty acids, mainly propionate, which the liver converts to glucose. Glucose is the main precursor for lactose in milk, so starch is a direct driver of milk volume.

High-quality alfalfa and grass hays provide digestible fiber and protein. They are less energy-dense than corn silage but contribute to rumen health and provide an important protein source. Many rations combine corn silage with alfalfa or grass hay to balance energy and fiber.

Grains and byproducts supply additional energy. Ground corn, high-moisture corn, barley, and wheat provide starch. Soybean hulls, corn gluten feed, wheat middlings, and citrus pulp provide digestible fiber with less starch. Fats and oils, such as roasted soybeans, cottonseed, and tallow, provide concentrated energy. Fat is about 2.25 times the energy of carbohydrates on a weight basis, but you must limit fat inclusion to about 5 to 6 percent of the diet dry matter to avoid depressing fiber digestion and milk fat.

Protein Sources for Dairy Cows

Protein sources are divided into forages, grains, oilseed meals, animal byproducts, and synthetic amino acids. Each source has a different balance of RDP and RUP.

Forages like alfalfa and grass provide protein that is mostly rumen-degradable. The protein in immature, leafy forages is highly degradable, while the protein in mature, stemmy forages is less degradable but also less digestible overall.

Soybean meal is the standard protein supplement for dairy rations. It has a good amino acid profile and provides both RDP and RUP. Canola meal, cottonseed meal, and sunflower meal are alternatives that vary in protein content and degradability.

Heat-treated soybean meal, fish meal, blood meal, and corn gluten meal provide higher levels of RUP. These bypass proteins are valuable for high-producing cows that need more amino acids than rumen microbes alone can supply. However, they cost more per unit of protein, so you need to use them where they pay off.

Synthetic amino acids, particularly lysine and methionine, are available as rumen-protected products. These can help you fine-tune the amino acid balance of the diet without oversupplying total protein. Work with your nutritionist to determine whether these products are economical for your herd.

Understanding the Energy Protein Ratio

The energy protein ratio is not a single fixed number. It changes with milk production level, stage of lactation, and the type of protein being fed. The most useful way to think about the ratio is in terms of grams of crude protein per megacalorie of NEL, or pounds of protein per pound of energy.

A typical lactating cow ration contains about 55 to 65 grams of crude protein per megacalorie of NEL. High-producing cows in early lactation need more protein per unit of energy because they are mobilizing body fat and need amino acids for milk protein synthesis. Low-producing cows in late lactation need less protein per unit of energy.

The rumen microbes have their own requirement for protein. They need about 8 to 10 percent crude protein in the diet dry matter, supplied as RDP, to grow and multiply. If the diet has less than this, fiber digestion drops and feed intake falls. If the diet has more RDP than the microbes can use, the excess is converted to urea and excreted.

Milk urea nitrogen (MUN) is a useful indicator of the energy protein balance. MUN is measured in milk and reflects the amount of urea in the blood. High MUN values, above about 14 to 16 milligrams per deciliter, suggest that protein is being wasted, either because there is too much RDP or not enough energy. Low MUN values, below about 8 to 10, suggest that protein may be limiting milk production. Work with your nutritionist to interpret MUN values for your herd, as levels vary with breed and production level.

Step-by-Step Guide to Ration Formulation

Ration formulation is a systematic process. Follow these steps to build a balanced ration for your herd.

Step 1: Define Your Feeding Groups

Group cows by stage of lactation and production level. A typical dairy has a fresh cow group, a high group, a mid group, and a low or late-lactation group. Dry cows are fed separately. Grouping allows you to feed closer to each cow's needs without overfeeding or underfeeding.

Fresh cows, those in the first 3 weeks after calving, need a diet that supports high intake and minimizes metabolic problems. High-producing cows in early to mid lactation need the most energy-dense diet. Late-lactation and low-producing cows can be fed a lower-cost diet with more forage.

If you have only one group, you will need to feed to the average of the group, which means some cows are overfed and some are underfed. That is acceptable on small farms but limits production efficiency.

Step 2: Estimate Dry Matter Intake

Use a prediction equation or your own herd records to estimate dry matter intake for each group. A simple rule of thumb for Holsteins is that DMI in pounds is about 3 to 4 percent of body weight, with higher intakes for high-producing cows. More precise equations use body weight, milk production, and days in milk.

Your nutritionist or extension agent can provide a prediction equation that fits your herd. The important point is to start with an intake estimate and then adjust it based on what you actually measure at the bunk.

Step 3: Set Nutrient Targets

Define the target levels for the key nutrients in each group's ration. These targets include dry matter intake, NEL, crude protein, RDP and RUP, NDF, ADF, starch, fat, calcium, phosphorus, and other minerals and vitamins.

The National Research Council (NRC) nutrient requirements for dairy cattle provide a reference for these targets, but many nutritionists use updated models and software that incorporate more recent research. Your extension agent can help you access current recommendations.

Step 4: Enter Forage Tests into Your Ration Program

Enter the forage test results into your ration balancing software. This is the starting point for the ration. Most software programs allow you to set maximum inclusion rates for each forage based on your inventory and feeding capacity.

The first pass at a ration usually maximizes forage use because forages are the cheapest source of nutrients on most farms. Then you add supplements to meet the nutrient targets.

Step 5: Add Supplements to Meet Energy and Protein Needs

Add grains, protein meals, and byproducts to bring the ration up to the energy and protein targets. Start with the cheapest sources of energy and protein, then add more expensive ingredients only if needed.

Check the ration for minimum and maximum inclusion rates for each ingredient. For example, do not exceed about 60 percent of the diet dry matter as corn silage if you are worried about starch overload. Do not feed more than about 5 to 6 percent fat from added fat sources.

Step 6: Check Fiber and Physical Form

Evaluate the NDF level of the ration. A typical lactating cow ration contains 28 to 34 percent NDF, with at least 19 to 21 percent coming from forage. Forage NDF is important for rumen health because it stimulates chewing and saliva production.

The physical form of the fiber matters too. Cows need a minimum amount of effective fiber, which is fiber that is long enough to promote chewing. If the ration is ground too fine, cows may not chew enough even if the NDF level is adequate.

Step 7: Balance Minerals and Vitamins

Add a mineral and vitamin premix to meet the cow's requirements for calcium, phosphorus, magnesium, potassium, sodium, sulfur, and trace minerals. The premix also supplies vitamins A, D, and E.

Pay special attention to the calcium and phosphorus levels in the dry cow ration because they affect milk fever risk. Work with your nutritionist to set the right levels for each group.

Step 8: Review the Ration on Paper

Check the final ration against the nutrient targets. Look at the energy protein ratio, the RDP to RUP balance, the starch level, and the forage NDF. Make sure the ration is physically feasible to mix and feed with your equipment.

Review the ration for cost per cow per day. Compare the cost of alternative ingredients. Sometimes a slightly more expensive ingredient is worth it if it improves intake or milk production.

Step 9: Mix and Feed the Ration

Weigh ingredients accurately. Calibrate your mixer wagon regularly. A TMR that is not mixed correctly can lead to sorting, inconsistent intake, and reduced milk production.

Load the mixer in the correct order. A typical order is to add long-stemmed forages first, then silages, then grains and concentrates, then liquids and additives. Follow your nutritionist's recommendation for your specific mixer and ingredients.

Step 10: Observe and Adjust

Watch the cows. Check that they are cleaning up the ration without excessive sorting. Look at manure consistency, body condition, and milk production. Use these observations to make small adjustments to the ration and to the feeding management.

Building a Total Mixed Ration

A total mixed ration is a blend of all feed ingredients formulated to provide a complete diet in every bite. The TMR is the standard feeding system on most modern dairy farms because it prevents sorting and ensures that every cow gets the same balance of nutrients.

To build a TMR, you need a mixer wagon with accurate scales. Weigh each ingredient as you load it into the mixer. The order of loading matters. Start with the dry forages, add the silages, then the grains and concentrates, and finish with liquids and additives. Mix for the recommended time, usually 3 to 5 minutes after the last ingredient is added. Overmixing reduces particle size and can cause rumen problems. Undermixing leaves clumps and allows sorting.

Check the particle size of the TMR regularly using a Penn State Particle Separator. This simple tool has three screens and a pan. It tells you the proportion of long particles, medium particles, short particles, and fine particles in the ration. A typical TMR for lactating cows should have about 2 to 8 percent on the top screen, 30 to 50 percent on the middle screen, 30 to 40 percent on the bottom screen, and less than 20 percent in the pan. Adjust mixing time and ingredient processing if the particle size is off.

Feed the TMR once or twice daily. Push feed up to the cows several times per day to encourage intake. Provide enough bunk space so that all cows can eat at the same time. A good rule is 24 inches of bunk space per cow for mature Holsteins, though some high-producing herds use more.

Common Mistakes in Ration Formulation

Farmers and feed managers make several common mistakes when balancing dairy cow diets. Recognizing these errors can save money and prevent herd health problems.

Guessing Forage Quality

The most common mistake is feeding forages without testing them. Forage quality varies widely. A corn silage crop harvested at the right moisture and maturity can be worth 10 or more pounds of milk per cow per day compared with an overmature crop. Without a forage test, you are flying blind.

Test every new forage lot before you feed it. If you cannot test before feeding, at least estimate the dry matter by microwaving a sample or using a Koster tester. Dry matter affects how much of the forage you need to add to the TMR to get the target dry matter intake.

Overfeeding Protein

Many farmers feed more protein than the cows need, thinking that extra protein means extra milk. That is not true. Once the cow has enough protein for milk production and body maintenance, extra protein is wasted. It costs money and increases nitrogen excretion.

Use MUN values and milk protein percentage to check whether your protein level is right. If MUN is high and milk protein is normal or low, cut back on protein. Work with your nutritionist to find the minimum protein level that maintains production.

Underfeeding Energy

Underfeeding energy is as common as overfeeding protein. Cows that do not get enough energy in the diet will mobilize body fat to make up the deficit. A little body fat mobilization in early lactation is normal, but too much leads to ketosis, fatty liver, and poor reproduction.

Check body condition scores regularly. If more than 20 percent of the herd has a body condition score below 2.5 on a 5-point scale, your energy level is probably too low. Increase the energy density of the ration or improve dry matter intake.

Ignoring Feed Bunk Management

A perfect ration on paper fails if the cows do not eat it. Feed bunks that are empty for hours, feed that is pushed up irregularly, and overcrowding all reduce intake. Cows that cannot eat when they want to will not reach their production potential.

Check the feed bunk several times per day. Push feed up so cows always have access. Keep feed fresh by removing stale refusals daily. Provide clean, fresh water at all times.

Making Sudden Ration Changes

Cows need time to adjust to new feeds. The rumen microbes take days to adapt to a new diet. Sudden changes cause drops in intake, milk production, and sometimes digestive upsets.

Introduce new feeds gradually over 7 to 10 days. If you are changing the forage source, blend the old and new forages together for a few days. If you are adding a new concentrate, increase the inclusion rate slowly.

Forgetting About Water

Water is the most important nutrient, yet it is often overlooked. A lactating cow drinks 25 to 50 gallons of water per day. Cows drink more when the weather is hot and when they eat more dry matter.

Provide clean, fresh water at all times. Locate waterers so that cows do not have to walk far from the feed bunk. Clean waterers regularly to prevent algae and biofilm buildup. In winter, make sure water does not freeze.

Monitoring the Ration and the Herd

Ration formulation is not a one-time event. It is an ongoing process of monitoring and adjustment. You need to track several indicators to know whether your feeding program is working.

Milk Production and Components

Milk production is the most obvious indicator. Track daily milk per cow and compare it with your herd's potential. Milk fat and milk protein percentages tell you about rumen function and energy balance.

Milk fat percentage is sensitive to fiber level and particle size. If milk fat drops below about 3.2 percent in Holsteins, check the fiber level and particle size of the ration. Milk protein percentage is related to energy intake. If milk protein drops, the cows may not be getting enough energy.

Milk urea nitrogen is a useful indicator of protein and energy balance. Most dairy records include MUN values. Work with your nutritionist to set a target range for your herd and track changes over time.

Body Condition Score

Body condition scoring is a visual and tactile assessment of the fat cover on the cow's back, ribs, and tailhead. The 5-point scale is standard, with 1 being emaciated and 5 being obese.

Score cows at calving, at peak lactation, at mid lactation, and at dry-off. Cows should lose no more than about 0.5 to 0.75 of a body condition score in early lactation. Cows that lose too much condition are at risk for ketosis, poor reproduction, and low milk production in the next lactation.

Manure Consistency

Manure tells you about rumen function. Normal dairy cow manure is a thick porridge that forms a pat about 1 to 2 inches thick when it hits the ground. Loose, runny manure with gas bubbles suggests acidosis or too much starch. Firm, dry manure suggests low intake or too much fiber.

Look for undigested feed particles in the manure. Corn kernels and long forage particles indicate poor kernel processing or sorting at the bunk. Use a manure sieve to separate the particles and check for problems.

Feed Refusals

Weight the refusals from each group daily. A typical target is 2 to 5 percent refusals on an as-fed basis. If refusals are above 5 percent, you are feeding too much and wasting money. If refusals are below 2 percent, the cows may be running out of feed and some cows may not get enough to eat.

Check the refusals for sorting. If the cows are leaving the long forage particles and eating the grain, they are sorting the ration. This can happen if the TMR is too dry, the particle size is wrong, or the cows have too much bunk space.

Feed Costs

Track the cost per cow per day for each feeding group. Compare this with the milk income per cow per day to calculate the income over feed cost (IOFC). The IOFC is a better measure of feeding efficiency than feed cost alone because it accounts for milk production.

Work with your nutritionist to identify opportunities to reduce feed costs without reducing production. This might involve buying ingredients in bulk, using alternative byproducts, or improving forage quality to reduce supplement use.

When to Call a Veterinarian or Extension Agent

Most ration adjustments can be handled by you and your nutritionist. But some situations require professional help beyond routine feeding advice.

Call a veterinarian immediately if you see multiple cows off feed, a sudden drop in milk production across the herd, or signs of severe metabolic disease. These signs can indicate acidosis, ketosis, milk fever, or a toxic feed problem. A veterinarian can diagnose the cause and provide treatment.

Call a veterinarian if cows are showing signs of lameness that does not respond to foot trimming, or if you see multiple cases of displaced abomasum, retained placenta, or metritis. These problems often have a nutritional component but require veterinary treatment.

Call your extension agent or a nutritionist if you are starting a new feeding program, changing forage sources, or building a new ration from scratch. They can help you set up the ration, interpret forage tests, and train your employees on feeding management.

Call an extension agent if you are considering a major change to your feeding system, such as switching from component feeding to a TMR, or if you want to evaluate the economics of a new feed ingredient. Extension agents can provide impartial advice and may have access to regional data on feed prices and availability.

Frequently Asked Questions

How often should I test my forages?

Test every new lot of forage before you feed it. For corn silage, test each time you open a new silo or bunker, or at least every 4 to 6 weeks during storage. For hay and haylage, test each cutting and each field. Forages change with storage time, so retest if you notice changes in color, smell, or moisture content.

What is the ideal energy protein ratio for a lactating cow?

There is no single ideal ratio because it changes with production level and stage of lactation. A practical target is 55 to 65 grams of crude protein per megacalorie of NEL for lactating cows. High-producing cows in early lactation need more protein per unit of energy. Use MUN values and milk protein percentage to fine-tune the ratio for your herd.

How much dry matter should a dairy cow eat per day?

A mature Holstein producing 80 to 100 pounds of milk typically eats 50 to 60 pounds of dry matter per day. Intake varies with body weight, production level, stage of lactation, and environmental conditions. Measure actual intake on your farm by weighing feed offered and refusals. Use that number to set your ration targets.

What is the difference between RDP and RUP?

Rumen-degradable protein (RDP) is broken down by microbes in the rumen to make microbial protein. Rumen-undegradable protein (RUP) escapes rumen breakdown and is digested in the small intestine. Both are important. The microbes need RDP to grow, and the cow needs RUP to meet her amino acid requirements for milk protein synthesis.

Why is my milk fat percentage low?

Low milk fat percentage often indicates a problem with fiber or particle size in the ration. Check the NDF level and the particle size using a Penn State Particle Separator. Other causes include too much starch, too much unsaturated fat, and sorting at the feed bunk. Work with your nutritionist to adjust the ration.

How do I know if I am overfeeding protein?

Check your milk urea nitrogen values. High MUN values, typically above 14 to 16 milligrams per deciliter, suggest that protein is being wasted. You can also look at your ration's crude protein level. If you are feeding more than 17 to 18 percent crude protein to lactating cows and MUN is high, you are likely overfeeding protein.

Can I balance a ration without a nutritionist?

You can learn to balance rations using software programs and published nutrient requirement tables, but it takes time and experience. A nutritionist brings expertise in ingredient selection, forage testing interpretation, and troubleshooting. Many farmers work with a nutritionist for the base ration and then make small adjustments themselves under the nutritionist's guidance.

What should I do if my cows go off feed?

First, check the feed bunk for signs of sorting or spoiled feed. Remove any spoiled or unpalatable feed. Check the TMR particle size and dry matter. Offer fresh, palatable feed and push it up frequently. If cows do not return to feed within 12 to 24 hours, or if you see signs of acidosis or other illness, call your veterinarian.

Related Farming Guides

This section will be populated programmatically with related farming guides on topics such as dry cow management, calf nutrition, forage production, and herd health monitoring. Check back for updates or search the site for additional resources on dairy herd management.

Related Clinical & Scientific Guides

References

USDA Farm Management: https://www.farmers.gov/
FAO Farm Management: https://www.fao.org/farmer-field-schools/en/
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.