# Swine Feed Sampling and Quality Testing Protocols ## Key Takeaways - Representative feed sampling is critical for accurate laboratory analysis; collect multiple subsamples from diverse locations (mill, bin, feeder) and combine them into a single composite sample, ensuring at least 1-2 pounds for standard nutrient analysis. - Routine testing should include moisture, crude protein, fat, fiber, calcium, phosphorus, and major amino acids (lysine, methionine, threonine, tryptophan) to verify formulation accuracy and prevent economic losses from nutrient deficiencies or excesses. - Mycotoxin panels are essential when corn quality is questionable or pigs exhibit unexplained feed refusal, vomiting, or reduced growth, as toxins like DON and aflatoxin can suppress immunity and cause organ damage. - Proper sample handling and labeling are paramount; use clean paper bags for moisture testing (never plastic), label with farm name, date, feed type, and exact location, and complete submission forms accurately detailing requested tests. - Consult a veterinarian immediately for sudden death, vomiting, severe diarrhea, or feed refusal coinciding with a feed change, as these can indicate acute mycotoxin toxicity, bacterial contamination, or severe nutritional imbalances. --- Feed represents the largest single cost in swine production, often accounting for 60 to 70 percent of total production expenses. When feed quality slips, pigs are the first to show it through reduced gain, poor feed conversion, digestive upset, or increased mortality. Yet many producers rely on visual inspection alone, which cannot detect nutrient imbalances, mycotoxin contamination, or bacterial spoilage. This guide walks through practical swine feed testing procedures, from taking a representative sample to interpreting laboratory results and acting on the findings. It is written for farm owners, herd managers, and employees who handle feed on a daily basis, and it assumes no prior laboratory experience. ## At a Glance - Sample feed at the mill, at the bin, and at the feeder for a complete picture of quality - Take multiple subsamples and combine them into one composite sample for accurate lab results - Collect at least 1 to 2 pounds of feed for a standard nutrient analysis - Test for moisture, crude protein, fat, fiber, calcium, phosphorus, and major amino acids on a routine basis - Run mycotoxin panels when corn quality is questionable or when pigs show unexplained feed refusal - Submit samples in clean paper bags or manufacturer-provided containers, never plastic bags for moisture testing - Label every sample with farm name, date, feed type, and the exact location where it was taken - Keep records of all test results and compare them against feed mill specifications - Call a veterinarian when you see feed refusal, vomiting, or sudden death that coincides with a feed change ## Why Feed Quality Testing Matters Swine feed testing is the process of collecting feed samples and submitting them to a laboratory for analysis of nutrient content, contaminant levels, or both. The goal is to verify that the feed you are delivering to the barn matches the formulation you intended to feed. Without testing, you are operating on trust alone, and feed mills can make errors, ingredient quality can vary from load to load, and on-farm mixing can introduce mistakes. The economic case for routine testing is straightforward. A feed that is deficient in lysine by just 0.1 percent can reduce daily gain by several percentage points in growing pigs. Over a 20-week grow-out period, that small deficiency translates into days of extra feed consumption and lighter market weights. Conversely, over-supplementing nutrients wastes money on ingredients the pigs cannot use. Calcium and phosphorus imbalance can trigger lameness and structural problems that force premature culling of breeding stock. Feed testing also protects herd health. Mycotoxins produced by molds in stored grain can suppress immunity, reduce feed intake, and damage liver and kidney function. Bacterial contamination with pathogens such as Salmonella can introduce disease into a clean herd. Testing gives you a chance to catch these problems before they spread through the barn. ## Understanding Feed Sampling Basics The single most important rule in feed testing is that the sample must represent the entire batch of feed. A sample from the top of a bin may be drier than the feed at the bottom. A handful from the first few seconds of a mill run may not match the middle of the batch. If the sample does not represent the whole, the laboratory results are meaningless no matter how accurate the analysis. Representative sampling requires collecting multiple subsamples from different locations and combining them into one composite sample. The number of subsamples depends on the source of the feed and the degree of variability you expect. Feed straight from a mixer that has been running for several minutes is relatively uniform. Feed from a bin that has been loaded over several days can vary considerably from top to bottom. Sampling equipment matters. A grain probe or sampling spear is a hollow tube with openings along its length that collects feed from multiple depths as you push it into the bin or bag. These probes are inexpensive and available from farm supply catalogs. For bagged feed, you can use a smaller probe or simply take handfuls from several bags. For feed in a bulk truck or railcar, sampling ports are usually available, and the driver or mill staff can assist. Never sample from a single location and assume it represents the whole batch. Always take multiple subsamples. The minimum is five, but ten or more is better when you suspect variability. Combine the subsamples in a clean bucket, mix them thoroughly by hand, and then take your final sample from that mixture. ## Sampling at the Feed Mill If you purchase feed from a commercial mill, you have the right to request sampling at the time of loading. Many mills have sampling equipment built into the loading spout that automatically collects a small portion of feed throughout the loading process. If your mill does not have this equipment, you can collect your own samples as the feed loads. Stand at the loading spout and take a small handful of feed at regular intervals throughout the entire loading process. Collect at least five to ten handfuls spread evenly from the start to the finish of loading. Place each handful into a clean bucket. Do not take all samples from the first few minutes of loading. After loading is complete, mix the contents of the bucket thoroughly and take your final sample. Place the sample in a clean container, label it clearly, and either submit it to a laboratory or store it in a cool, dry place until you are ready to send it. Keep a portion of every feed delivery for your records. Many producers keep a "retained sample" from each load in a labeled container for 30 to 60 days. If a problem arises later, you can test the retained sample to determine whether the feed was at fault. ## Sampling from Bins and Bulk Storage Feed stored in bins can stratify by particle size, moisture content, and density. Fine particles tend to settle toward the center, while larger particles roll to the outside. Moisture can migrate to the top and sides of the bin, creating pockets of mold growth. For these reasons, sampling from a bin requires more care than sampling at the mill. The best time to sample a bin is when it is being filled or emptied, because the moving feed is more likely to be well mixed. If you must sample a static bin, use a grain probe to collect cores from multiple locations. Insert the probe at several points around the bin, including the center, the edges, and at least two intermediate positions. Take samples from the top, middle, and bottom of the bin if the probe is long enough to reach. For bins that are emptied from the bottom, collect samples from the discharge spout while the feed is flowing. Take a small portion every few seconds throughout the entire emptying process. This method gives you a much more representative sample than probing a static bin. Do not climb into a bin to sample feed. Bins can develop crusts and bridges that collapse without warning, and the risk of entrapment or suffocation is serious. Use a probe from outside or sample during flow. ## Sampling from Feeders and Feeding Systems Feed in the feeder is what the pigs actually consume, so it is the most relevant sample for diagnosing a feed-related problem. However, feeder samples are also the most variable because pigs sort feed, pushing pellets aside to reach fines, and because feed accumulates moisture and dust in the feeder trough. When you suspect a feed problem, sample from multiple feeders across the barn. Take small amounts from the trough, the feeder body, and any residual feed in the bottom of the pan. Combine these into one composite sample. Do not pick out only the fines or only the pellets, because that would not represent what the pigs are actually eating. For automated feeding systems, sample from the drop point where feed falls into the feeder. Collect a small amount from several drops throughout the day to capture variability. If the system delivers feed at set intervals, sample at different times of day to account for any separation that occurs during delivery. Feeder samples are best used for troubleshooting rather than routine quality monitoring. Because they are so variable, they are not ideal for verifying nutrient content. If a feeder sample shows a serious problem, confirm it with a sample from the bin or the mill before taking corrective action. ## Sampling Procedures for Different Feed Forms The physical form of the feed affects how you should sample it. Pelleted feed is relatively easy to sample because the pellets are uniform in size and density. Meal feed is more variable because fine particles and larger particles can separate. Liquid feed requires different equipment and handling. For pelleted feed, collect whole pellets in your sample. Do not crush them before submission. The laboratory will grind the sample as part of its preparation. If you are concerned about pellet quality, you can also request a pellet durability index test, which measures how well the pellets hold together during handling and feeding. For meal feed, be extra careful to collect a representative sample because particle size segregation is common. Mix the subsamples thoroughly in a bucket before taking your final sample. If you see obvious clumps or foreign material, note this on the submission form and include a separate sample of the unusual material for identification. For liquid feed or liquid supplements, stir the container thoroughly before sampling because ingredients can settle out. Use a clean ladle or dipper to collect the sample, and place it in a clean plastic container with a tight lid. Do not use glass containers for liquid feed because they can break in transit. Most laboratories have specific requirements for liquid samples, so check with them before submitting. ## How Much Feed to Submit The amount of feed you need to submit depends on the type of analysis you are requesting. A standard proximate analysis, which measures moisture, protein, fat, fiber, and ash, requires about 1 pound of feed. A complete amino acid profile requires a similar amount. A mycotoxin panel requires about 1 pound as well. If you are requesting multiple tests on the same sample, submit 2 pounds to ensure the laboratory has enough material. Some laboratories can run multiple tests from a single sample, but it is safer to provide extra. Do not submit more than 2 pounds unless the laboratory specifically requests a larger sample. For samples that are difficult to collect, such as liquid feed or feed with large particles, call the laboratory in advance to confirm their minimum sample size. Laboratories vary in their requirements, and a call can save you the frustration of a rejected sample. ## Choosing the Right Sample Container The container you use for feed samples is more important than most producers realize. The wrong container can introduce moisture, contaminate the sample, or cause the laboratory to reject it. Use clean paper bags or the sample bags provided by the laboratory. Paper allows moisture to escape, which is important when you are testing for moisture content. Do not use plastic bags for dry feed samples destined for moisture analysis, because the plastic traps moisture and will give you falsely high moisture readings. For samples that will be tested for mycotoxins, use the bags provided by the laboratory if possible. These bags are designed to prevent contamination and are often pre-labeled. If you use your own bags, make sure they are clean and have never been used for chemicals, fertilizers, or other non-feed materials. For liquid samples, use clean plastic containers with tight-fitting lids. Glass is acceptable but more likely to break in transit. Label the container clearly and tape the lid shut to prevent leakage. ## Labeling Your Samples Every sample you submit must be labeled clearly and completely. A sample without a label is worthless because the laboratory cannot tell you what it is or where it came from. Use a permanent marker to write directly on the bag or on a label that is firmly attached. Include the following information on every label: - Farm or business name - Date and time of sampling - Feed type or product name - Batch number or load number if available - Exact location where the sample was taken - Your name and contact information - Any unusual observations about the feed Write legibly. If you use a label, make sure it is waterproof and will not fall off during shipping. Many laboratories provide pre-printed submission forms that include space for all of this information. Fill out the form completely and include it with your sample. ## Completing the Laboratory Submission Form Most feed testing laboratories require a submission form that accompanies your sample. This form tells the laboratory what tests to run and provides the information they need to interpret the results. Fill out the form completely and accurately. Include the following on your submission form: - Your contact information and billing information - The type of feed and the species and age of the animals it is intended for - The tests you are requesting - Any known information about the feed such as the formulation or ingredient list - The reason for testing, such as routine monitoring or troubleshooting a problem Be specific about the tests you want. A standard nutrient analysis includes moisture, crude protein, crude fat, crude fiber, and ash. If you also need calcium, phosphorus, and major amino acids, request these as additions. If you suspect mycotoxins, request a mycotoxin panel that includes the specific toxins common in your region. If you are unsure what tests to request, call the laboratory and describe your situation. The laboratory staff can help you choose the right tests for your needs. It is better to ask before you submit than to receive results that do not answer your question. ## Shipping Your Samples Feed samples are not hazardous materials, so shipping is straightforward. Package the samples securely to prevent breakage or leakage during transit. Use a sturdy cardboard box and pack the samples with bubble wrap or crumpled paper to keep them from shifting. Ship samples early in the week to avoid weekend delays. Feed samples degrade over time, especially in warm weather, so faster shipping gives you more accurate results. Use overnight or two-day shipping for samples that will be tested for moisture, vitamins, or other unstable components. Do not ship samples on Friday unless you are using overnight shipping and the laboratory confirms they will receive them on Saturday. Samples that sit in a hot warehouse over the weekend can develop mold or lose moisture, which will skew your results. If you are shipping during hot weather, consider using an insulated container with a cold pack. Do not freeze the samples, because freezing can affect some nutrient analyses. Keep the samples cool but not frozen. ## Understanding the Standard Nutrient Analysis The standard nutrient analysis, sometimes called a proximate analysis, is the foundation of feed quality testing. It measures the major components of the feed and gives you a baseline for comparison. The results are reported as percentages on an as-fed or dry matter basis. Moisture content is the amount of water in the feed. It affects feed stability, mold growth, and the concentration of other nutrients. Feed with high moisture content can spoil quickly and may be lower in energy than the formulation intended. Moisture above 13 to 14 percent in stored feed increases the risk of mold growth. Crude protein is a measure of the total nitrogen content of the feed. It includes true protein and non-protein nitrogen. Crude protein gives you a general idea of the protein content, but it does not tell you about the quality of the protein or the levels of individual amino acids. For swine, the amino acid profile is more important than the crude protein level. Crude fat is the ether-extractable portion of the feed, which includes fats, oils, and waxes. Fat is a concentrated energy source, and its level affects feed palatability and dustiness. Fat levels that are too low can reduce energy intake, while levels that are too high can cause feed handling problems. Crude fiber is the indigestible portion of the feed. High fiber levels reduce the energy density of the feed and can limit feed intake in young pigs. Fiber levels that are too low can cause digestive upset in sows and growing pigs. Ash is the mineral residue left after the feed is burned. It gives you a rough estimate of the total mineral content but does not tell you about individual minerals. High ash levels can indicate contamination with soil or other foreign material. ## Testing for Major Minerals Calcium and phosphorus are the two minerals that most often cause problems in swine feed. They work together in bone development, and an imbalance in their ratio can cause lameness, fractures, and poor growth. The ideal calcium to phosphorus ratio for growing pigs is approximately 1.2 to 1.5 to 1. Calcium deficiency can cause rickets in young pigs and osteomalacia in older animals. Excess calcium can interfere with phosphorus absorption and reduce growth. Testing for calcium is straightforward and should be part of your routine analysis. Phosphorus is available in different forms, and not all phosphorus in feed ingredients is digestible by pigs. Phytate phosphorus in plant ingredients is largely unavailable to pigs unless phytase enzyme is added to the feed. When you test for phosphorus, ask the laboratory whether they measure total phosphorus or available phosphorus. Other minerals to consider testing include sodium, potassium, magnesium, zinc, copper, and selenium. These are less likely to cause problems than calcium and phosphorus, but they can become deficient or toxic under certain conditions. If you source ingredients from a new supplier or change your formulation, test for these minerals at least once. ## Testing for Amino Acids Amino acids are the building blocks of protein, and they are the most important nutrient to get right in swine feed. Pigs do not have a requirement for crude protein itself, but for specific amino acids. Lysine is the first limiting amino acid in most swine diets, meaning it is the amino acid most likely to be deficient. The key amino acids to test for in swine feed are lysine, methionine, threonine, and tryptophan. These four are the most commonly limiting in corn-soybean meal diets. If you use other ingredients such as dried distillers grains, canola meal, or field peas, you may also want to test for valine and isoleucine. Amino acid analysis is more expensive than a standard proximate analysis, but it is worth the cost for breeding stock and growing pigs. A deficiency in lysine of just 0.05 percent can reduce daily gain by 3 to 5 percent. Over the course of a grow-out period, that translates into a measurable loss in revenue. When you receive amino acid results, compare them against your feed formulation specifications. The laboratory report will show the percentage of each amino acid on an as-fed basis. Your nutritionist or feed supplier can help you interpret the results and adjust the formulation if needed. ## Testing for Mycotoxins Mycotoxins are toxic compounds produced by molds that grow on grains and feed ingredients. They are a serious concern in swine production because they can cause feed refusal, vomiting, reduced growth, immune suppression, and reproductive failure. The most important mycotoxins for swine are aflatoxin, deoxynivalenol (DON or vomitoxin), zearalenone, fumonisin, and ochratoxin. Aflatoxin is produced by Aspergillus molds and is most common in corn grown under drought stress. It is a potent liver toxin and carcinogen. The FDA action level for aflatoxin in swine feed is 20 parts per billion for growing pigs and 100 parts per billion for breeding stock. Deoxynivalenol, also called DON or vomitoxin, is produced by Fusarium molds and is common in corn and wheat. It causes feed refusal and vomiting at levels above 1 part per million. Pigs are more sensitive to DON than most other species. Zearalenone is also produced by Fusarium molds and has estrogenic effects. It can cause vulvar swelling in gilts, reduced litter size, and reproductive problems in sows. Levels above 1 part per million are a concern for breeding stock. Fumonisin is produced by Fusarium molds and can cause pulmonary edema in pigs at high levels. The FDA guidance level for fumonisin in swine feed is 20 parts per million, but lower levels may still affect growth. Ochratoxin is produced by Penicillium and Aspergillus molds and can cause kidney damage. It is less common than the other mycotoxins but is a concern in certain regions. Mycotoxin testing is not needed on every batch of feed, but it is essential when you suspect a problem. Signs that warrant mycotoxin testing include unexplained feed refusal, reduced growth, vomiting, diarrhea, and reproductive problems. You should also test when you are using corn that was harvested under stressful conditions such as drought, excessive rain, or early frost. The most common mycotoxin test is an ELISA panel that detects multiple toxins at once. These panels are relatively inexpensive and give results in a few days. More sensitive tests such as LC-MS/MS are available for confirmation and for detecting less common toxins. ## Testing for Pathogenic Bacteria Bacterial contamination of feed is less common than mycotoxin contamination but can be more dangerous. Salmonella is the pathogen of greatest concern in swine feed because it can cause clinical disease in pigs and is a public health concern. Feed ingredients such as oilseed meals and animal byproducts are the most common sources of Salmonella contamination. Testing for Salmonella requires specialized laboratory procedures and is more expensive than nutrient or mycotoxin testing. It is not needed on a routine basis for most farms. Test for Salmonella when you suspect a feed-borne disease outbreak, when a feed ingredient supplier has had a recall, or when regulatory requirements demand it. Other bacteria that can be present in feed include E. coli, Clostridium, and Listeria. These are less common in dry feed but can be a concern in liquid feeding systems or in feed that has been contaminated with water or feces. If you test for bacteria, collect your samples with extra care to avoid contamination. Use sterile containers and clean sampling equipment. Do not combine subsamples from multiple locations for bacterial testing, because you need to identify the source of the contamination. Take separate samples from each location and submit them individually. ## Testing for Feed Additives If you include medications, probiotics, enzymes, or other additives in your feed, you may want to verify that they are present at the correct levels. Medication testing is important because under-dosing can lead to treatment failure and over-dosing can cause toxicity or violative residues. Testing for medications is more complex and expensive than nutrient testing. It requires specialized analytical methods and is not available from all laboratories. If you need medication testing, ask your feed mill or veterinarian for a laboratory recommendation. For enzymes such as phytase, testing is complicated because the enzyme activity can be affected by heat during pelleting and by storage conditions. If you are concerned about enzyme activity, talk to your feed supplier about their quality control procedures. Probiotics and other live microbial additives are difficult to test accurately because the organisms must be cultured under specific conditions. Most producers rely on the manufacturer's quality control for these products. ## Interpreting Your Test Results When you receive your laboratory report, the first thing to check is whether the results are reported on an as-fed or dry matter basis. As-fed means the nutrient percentages are based on the feed as it is consumed, including its natural moisture content. Dry matter basis means the moisture has been removed for calculation purposes. The two bases give different numbers, and comparing them directly will lead to errors. Most feed formulations are expressed on an as-fed basis, so compare your results to your formulation specifications on the same basis. If your laboratory reports on a dry matter basis, convert the results before comparing. The second thing to check is whether the results fall within the expected range for your feed type. A complete grower feed should have roughly 15 to 18 percent crude protein, 3 to 6 percent crude fat, and 3 to 5 percent crude fiber on an as-fed basis. These ranges vary depending on your formulation, so use your specifications as the reference. If a nutrient is outside the expected range, do not panic. Consider the possibility of sampling error. A single sample from one location may not represent the whole batch. Take another sample and submit it for confirmation before making changes to your feeding program. ## Common Mistakes in Feed Sampling The most common mistake in feed sampling is taking too few subsamples. A single handful from the top of a bin tells you almost nothing about the feed at the bottom. Always take multiple subsamples and combine them. Another common mistake is sampling from the wrong location. Feed that has been sitting in a feeder for several days is not the same as fresh feed from the mill. If you want to know what the pigs are eating, sample the feeder. If you want to verify the feed you ordered, sample at the mill or bin. Using dirty sampling equipment is another frequent error. A probe that has residue from a previous sample can contaminate your current sample. Clean your equipment with a brush and a clean cloth between samples. Do not use soap or water unless you dry the equipment completely, because moisture can affect the sample. Submitting a sample that is too small is also a problem. Laboratories need a minimum amount of feed to run their analyses. If you submit less than the minimum, the laboratory may reject your sample or run only a limited panel. Forgetting to label your sample is a costly mistake. An unlabeled sample cannot be matched to a specific batch of feed, making the results useless. Label every sample before you submit it. ## How Often to Test Feed The frequency of feed testing depends on your operation and your risk tolerance. A commercial operation feeding thousands of pigs per year should test more frequently than a small farm feeding a few dozen pigs. At a minimum, test every new batch of feed from a new supplier or a new formulation. This gives you a baseline for comparison and catches problems before they affect the herd. For ongoing quality monitoring, test monthly or quarterly. Sample one batch of each feed type you use, such as starter, grower, finisher, and sow feed. Rotate which batch you sample so that you cover all feed types over time. Test more frequently when you change ingredient suppliers, when you use ingredients from a new crop year, or when you have experienced feed-related problems in the past. Corn from a new harvest is more likely to have mycotoxin problems than corn that has been stored for several months. ## Monitoring Feed Quality on the Farm Beyond laboratory testing, you can monitor feed quality on the farm using simple observations and tests. These do not replace laboratory analysis, but they give you early warning of problems. Check the temperature of feed in bins and feeders. Warm feed can indicate microbial activity or spoilage. Feed that is noticeably warmer than the surrounding air should be investigated. Look for mold growth on feed surfaces. Mold appears as fuzzy patches of green, black, white, or pink. If you see mold, test the feed for mycotoxins before feeding it to the pigs. Smell the feed. Fresh feed has a pleasant, slightly sweet or nutty odor. Sour, musty, or rancid odors indicate spoilage. Do not feed spoiled feed to pigs. Check the particle size and uniformity of meal feed. Feed that is too fine can cause dust problems and reduce feed intake. Feed that is too coarse can allow pigs to sort out ingredients. Observe the pigs. Feed intake is one of the most sensitive indicators of feed quality. If pigs suddenly reduce their intake after a new batch of feed is delivered, test the feed before assuming the pigs are sick. ## Recordkeeping for Feed Testing Good recordkeeping is essential for an effective feed quality program. You need to be able to trace a feed problem back to a specific batch, and you need to document your testing history for regulatory purposes and for your own management decisions. Keep a feed testing log that records the following for every sample: - Date of sampling - Location of sampling - Feed type and batch number - Laboratory name and report number - Tests requested - Results summary - Any corrective actions taken Store your laboratory reports in a file, either paper or electronic. Keep them for at least three years, or longer if you are involved in a lawsuit or regulatory action. Use your records to identify trends. Is your feed consistently low in lysine? Is moisture creeping up during the summer months? These trends can help you prevent problems before they cause losses. Share your test results with your feed supplier and your nutritionist. They can use the information to adjust formulations and improve quality control. A good feed supplier will welcome the feedback and work with you to resolve any issues. ## When to Call a Veterinarian Some feed problems look like disease outbreaks, and some disease outbreaks look like feed problems. If pigs show signs of illness that could be feed-related, call your veterinarian for guidance. Call a veterinarian immediately if you see any of the following: - Sudden death in multiple pigs shortly after a feed change - Vomiting or severe diarrhea in multiple pigs - Feed refusal lasting more than 24 hours - Neurological signs such as tremors, incoordination, or seizures - Abortions or stillbirths in sows These signs can indicate mycotoxin toxicity, bacterial contamination, or a nutritional emergency. Your veterinarian can help you determine whether the feed is the cause and can recommend treatment and testing. Do not wait to see if the problem resolves on its own. Feed-related problems can escalate quickly, and early intervention can save pigs and money. ## When to Call Your Extension Agent Your local cooperative extension agent can help you with feed sampling and testing in several ways. Extension agents can recommend laboratories, help you interpret test results, and provide guidance on feed formulation and quality management. Call your extension agent when you are setting up a new feed testing program, when you receive test results that you do not understand, or when you are considering changes to your feeding program. Extension agents have access to university resources and can connect you with swine nutritionists and other specialists. Extension agents can also help you compare feed testing laboratories and understand the differences in testing methods and reporting. They can provide educational materials on feed quality and can sometimes arrange for group testing discounts. ## Building a Feed Quality Program A feed quality program does not have to be complicated or expensive. The key elements are consistent sampling, regular testing, careful recordkeeping, and clear communication with your feed supplier and veterinarian. Start by establishing a baseline. Test each of your feed types at least once to know what you are currently feeding. Compare the results to your formulation specifications and investigate any significant differences. Next, set a testing schedule. Decide how often you will test each feed type and stick to the schedule. Monthly testing is reasonable for most operations. If you have had feed problems in the past, test more frequently. Train your employees on proper sampling procedures. A sampling error can waste money and lead to incorrect decisions. Make sure everyone who handles feed knows how to take a representative sample and how to label and submit it. Review your test results regularly. Do not just file the reports and forget them. Compare results over time and look for trends. Investigate any unexpected results promptly. Finally, build relationships with your feed supplier, your veterinarian, and your extension agent. These professionals can help you interpret results and solve problems. They are valuable resources, and they are most effective when they know your operation and your history. ## Feed Testing Laboratories Several types of laboratories offer feed testing services. Commercial feed testing laboratories are private businesses that offer a range of tests at competitive prices. University laboratories often offer testing services to producers and may have lower fees for in-state clients. Some feed mills operate their own laboratories and may offer testing to their customers. When choosing a laboratory, consider the following factors: - Accreditation and quality control procedures - Range of tests offered - Turnaround time for results - Cost per test - Customer service and technical support - Experience with swine feed Ask for recommendations from your veterinarian, extension agent, or neighboring producers. A laboratory that is used by many swine operations in your area is likely to be reliable and responsive. Before submitting your first sample, call the laboratory and ask about their submission requirements. Ask how they want samples packaged, what forms they require, and how they report results. This advance preparation will make the process smoother. ## Cost of Feed Testing The cost of feed testing varies by laboratory, by the type of test, and by the number of samples you submit. A standard proximate analysis typically costs between 30 and 60 dollars per sample. Adding minerals and amino acids can bring the total to 80 to 150 dollars per sample. Mycotoxin panels cost 50 to 150 dollars depending on the number of toxins tested. These costs are small compared to the potential losses from feeding a bad batch of feed. A single load of feed for a 1,000-head finishing barn can cost 15,000 dollars or more. Testing that load costs less than 1 percent of its value. Many laboratories offer volume discounts for producers who submit multiple samples at once. Some offer subscription programs with a set number of tests per month or per year. Ask about these options if you plan to test regularly. ## Troubleshooting Feed-Related Problems When pigs show signs of a feed-related problem, act quickly and systematically. The goal is to identify the cause and correct it before the herd suffers further losses. First, document the signs. Note which groups of pigs are affected, when the signs started, and what you have changed recently. This information will help your veterinarian and your laboratory interpret the results. Second, take samples. Sample the feed from the feeder, from the bin, and from any retained samples from the mill. Label each sample clearly with its location. Submit them for testing as soon as possible. Third, isolate the problem. If one group of pigs is affected and another is not, compare the feed they are receiving. The affected group may have received a different batch of feed, or the feeding system may have introduced contamination. Fourth, consider removing the suspect feed. If pigs are refusing feed or showing signs of toxicity, stop feeding the suspect feed and offer a known good feed. This can be expensive, but it may be cheaper than losing pigs. Finally, work with your veterinarian and your feed supplier to determine the cause and prevent a recurrence. The goal is not just to fix the immediate problem but to identify the weak point in your system that allowed it to happen. ## Frequently Asked Questions **How often should I test my swine feed?** Test every new batch of feed from a new supplier or new formulation. For ongoing monitoring, test monthly or quarterly, rotating among your feed types. Test more frequently when you change ingredient suppliers, when you use new crop ingredients, or when you have had feed problems in the past. **What is the difference between as-fed and dry matter basis?** As-fed basis reports nutrient percentages in the feed as it is consumed, including its natural moisture. Dry matter basis removes the moisture before calculating percentages. Dry matter numbers are always higher than as-fed numbers for the same feed. Always compare results on the same basis as your formulation specifications. **How much feed do I need to submit for testing?** Most laboratories need about 1 pound of feed for a standard nutrient analysis and about 2 pounds if you request multiple tests. Submit 2 pounds to be safe. For liquid feed, check with the laboratory for their specific requirements. **Can I test feed for mycotoxins myself?** Simple test strips are available for some mycotoxins, but they are not as accurate as laboratory testing. Use on-farm test strips for screening, and confirm any positive results with a laboratory test. Laboratory testing is the only reliable way to get accurate mycotoxin levels. **What should I do if my feed test shows a nutrient deficiency?** First, confirm the result with a second sample. Sampling errors can produce misleading results. If the deficiency is confirmed, contact your feed supplier and your nutritionist. They can help you determine whether the problem is in the formulation or in the ingredient quality, and they can recommend corrective action. **How long can I store a feed sample before testing?** Feed samples begin to degrade immediately. Moisture content changes, vitamins degrade, and molds can grow. For most tests, submit your sample within a few days of collection. If you must store a sample, keep it in a cool, dry place and submit it as soon as possible. **What are the most important tests for swine feed?** The most important tests are moisture, crude protein, calcium, phosphorus, and the key amino acids lysine, methionine, threonine, and tryptophan. These nutrients have the greatest impact on pig performance and are the most likely to be deficient or imbalanced. **Should I test feed for Salmonella?** Routine Salmonella testing is not necessary for most farms. Test when you suspect a feed-borne disease outbreak, when a feed ingredient supplier has had a recall, or when regulatory requirements demand it. If you do test, use sterile sampling procedures and submit separate samples from each location. ## Related Farming Guides This section will be populated with links to related farming guides on swine nutrition, feed formulation, herd health management, and other relevant topics. ## Related Clinical & Scientific Guides * [Pig Enrichment Programs and Behavior Monitoring](/knowledge/animal-farming/swine/pig-enrichment-programs-and-behavior-monitoring) * [Swine Handling Facility Design for Safe Pig Movement](/knowledge/animal-farming/swine/swine-handling-facility-design-safe-pig-movement) * [Swine Feeding Management for Grow-Finish Pigs](/knowledge/animal-farming/swine/swine-feeding-management-for-grow-finish-pigs) ## References - National Pork Board: https://www.pork.org/ - USDA APHIS Swine Health: https://www.aphis.usda.gov/livestock-poultry-disease/swine - FAO Pig Production: https://www.fao.org/pig-production-and-products/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.