Nursery Pig Feed Ingredients and Additives Selection

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

Key Takeaways

• Nursery pig diets must prioritize digestibility and palatability over cost per ton due to the immature digestive system post-weaning, necessitating highly digestible protein sources like plasma, fish meal, or highly processed soybean meal, alongside milk products.
• Pharmacological levels of zinc oxide (2,000-3,000 ppm) are effective in reducing post-weaning diarrhea within the first two weeks by exerting antimicrobial and gut barrier enhancement effects, but require adherence to withdrawal periods and local regulations.
• Copper, commonly added at 100-250 ppm, supports growth through antimicrobial actions and enzyme stimulation, with copper proteinate offering higher bioavailability and reduced environmental impact compared to copper sulfate.
• Phase feeding, involving three to four diet changes from weaning to approximately 60 pounds, is crucial for cost-effectively matching nutrient requirements with pigs' developing digestive capacity and growth stages.
• Monitoring average daily gain, feed intake, mortality, and fecal consistency weekly, particularly in the first two weeks post-weaning, is critical for early detection of health issues and performance deviations, prompting veterinary consultation for persistent diarrhea, high mortality, or feed refusal.
• The selection of additives such as acidifiers, probiotics, prebiotics, and enzymes is contingent on herd health status, facility hygiene, and diet complexity, with their efficacy varying and requiring careful evaluation for optimal gut health and nutrient utilization.

Raising healthy piglets through the nursery phase requires careful attention to diet formulation. The feed you provide between weaning and roughly 60 pounds of body weight sets the foundation for lifetime performance, immune development, and growth efficiency. This guide covers the full range of nursery pig feed ingredients and additives, explaining what each component does, how to select the right ones for your operation, and how to monitor results. It is written for independent swine producers, farm managers, and anyone responsible for formulating or purchasing nursery diets. You will learn which ingredients matter most, which additives deserve your budget, and how to avoid costly formulation mistakes.

At a Glance

• Weaning creates a sudden shift from sows milk to solid feed, so nursery diets must prioritize digestibility and palatability above cost per ton.
• The first nursery diet after weaning should include highly digestible protein sources like plasma, fish meal, or high-quality soybean meal, plus milk products to support intake.
• Zinc oxide at pharmacological levels (2,000 to 3,000 ppm) can reduce post-weaning diarrhea in the first two weeks, but you must follow withdrawal periods and local regulations.
• Copper and zinc are the most common trace mineral additives in nursery feed, with copper often added at 100 to 250 ppm to support growth.
• Acidifiers, probiotics, prebiotics, and enzymes can improve gut health and nutrient use, but their benefits depend on diet complexity and farm hygiene.
• Phase feeding with three to four diet changes over the nursery period reduces feed cost while maintaining growth performance.
• Monitor average daily gain, feed intake, mortality, and fecal consistency weekly during the first two weeks after weaning.
• Call your veterinarian if diarrhea persists beyond three days, mortality exceeds 2 percent in the first week, or pigs refuse feed for more than 24 hours.

Understanding the Nursery Pig Digestive System

The nursery phase spans from weaning at roughly 3 to 4 weeks of age until pigs reach about 55 to 70 pounds. During this period the digestive system undergoes dramatic changes. A newborn piglet has an immature digestive tract designed for frequent small meals of highly digestible sows milk. At weaning the pig loses that steady supply of antibodies and easily digested nutrients and must adapt to dry feed.

The stomach of a young pig produces limited hydrochloric acid. This means gastric pH stays higher than in older pigs, which reduces the activity of pepsin and other protein-digesting enzymes. Pancreatic enzymes like amylase, lipase, and trypsin are present but at lower levels than in mature pigs. The small intestine has a large surface area but the brush border enzymes needed to digest complex carbohydrates and proteins develop gradually over the first two to three weeks after weaning.

This immature digestive system explains why ingredient selection matters so much. Feeds that work well for grow-finish pigs can cause digestive upset, poor growth, and diarrhea in nursery pigs. The goal of nursery feed formulation is to match ingredient complexity with the pigs developing enzyme capacity. As the pig matures, you can gradually introduce less expensive, more complex ingredients.

Nursery Pig Feed Ingredients: The Building Blocks

Cereal Grains and Energy Sources

Corn is the primary energy source in most US nursery diets. It provides starch that pigs digest well when properly processed. Hammer-milled or roller-milled corn with a particle size of 600 to 700 microns works best for nursery pigs. Finer grinding improves digestibility but increases the risk of stomach ulcers and feed bridging in bins. Coarser grinding reduces digestibility and can increase feed wastage.

Wheat is another excellent energy source for nursery diets. It has slightly higher protein content than corn and is highly palatable. Wheat can replace up to 30 to 50 percent of corn in nursery diets without reducing performance. If you feed wheat, adjust the diet for its higher protein and phosphorus content. Wheat also requires slightly coarser grinding than corn, around 700 to 800 microns, to avoid pasty feces.

Barley and oats are less common in US nursery diets but work well in some regions. Barley has lower energy than corn but provides good fiber and can help reduce diarrhea in some herds. Oats, particularly hulled oats, are highly digestible and palatable but more expensive. They work well in the first nursery diet for very young weaned pigs.

Bakery meal and other processed grain byproducts can reduce feed cost but vary in quality. If you use these ingredients, test each load for moisture, fat content, and mycotoxins. Bakery meal can contain high fat levels that become rancid in warm weather.

Protein Sources

Protein is the most critical and expensive component of nursery diets. The young pig needs high levels of digestible amino acids for rapid muscle growth, but its immature digestive system cannot handle complex proteins efficiently. This creates a tension between cost and digestibility that drives most nursery formulation decisions.

Plasma Protein

Spray-dried animal plasma is the gold standard protein source for the first nursery diet. It is highly digestible, extremely palatable, and contains immunoglobulins that provide passive immunity to the newly weaned pig. Research consistently shows that plasma improves feed intake, growth rate, and reduces post-weaning diarrhea. Use plasma at 4 to 8 percent of the first nursery diet and 2 to 4 percent of the second diet.

The main drawback of plasma is cost. It is one of the most expensive ingredients in swine nutrition. Some producers reduce or eliminate plasma to cut feed costs, but this often leads to poorer performance in the first week after weaning. If you use plasma, source it from reputable suppliers that follow strict biosecurity and processing standards.

Fish Meal

Fish meal is another highly digestible protein source that works well in nursery diets. It provides excellent amino acid balance, particularly methionine and lysine, and contains omega-3 fatty acids that support immune function. Use fish meal at 3 to 8 percent of the first and second nursery diets.

Quality varies significantly among fish meal sources. Look for meals with low ash content and consistent protein levels. Menhaden fish meal is the most common in US swine diets. Avoid fish meal with high levels of biogenic amines, which reduce palatability and can cause stomach ulcers.

Soybean Meal

Soybean meal is the workhorse protein source in swine diets, but its use in nursery diets requires care. Conventional soybean meal contains antinutritional factors including trypsin inhibitors, lectins, and oligosaccharides that can cause digestive upset in young pigs. These compounds are largely destroyed by proper heat processing, but residual activity remains.

For the first nursery diet, use only highly processed soybean products. Enzyme-treated soybean meal or fermented soybean meal has lower antinutritional factors and higher digestibility. These products cost more than conventional soybean meal but support better performance in the critical first week after weaning.

Conventional soybean meal can enter the diet at 15 to 25 percent in the second and third nursery phases. By the fourth phase, pigs can handle conventional soybean meal at levels comparable to grow-finish diets. The key is to match soybean meal inclusion with the pigs developing digestive capacity.

Dairy Products

Dried whey and dried skim milk are traditional ingredients in the first nursery diet. They provide lactose, which is highly digestible and palatable to young pigs, plus high-quality protein. Dried whey also contains minerals and vitamins that support gut health.

The use of dairy products has declined in recent years due to cost and the development of alternative ingredients. However, they remain valuable in the first diet, particularly for pigs weaned before 21 days of age. Use dried whey at 10 to 20 percent of the first nursery diet and 5 to 10 percent of the second diet.

Lactose is the key component of whey for nursery pigs. It provides a readily available energy source that supports the growth of beneficial bacteria in the gut. If whey is too expensive, consider lactose-only products or other highly digestible carbohydrate sources.

Other Protein Sources

Potato protein concentrate, rice protein concentrate, and pea protein are alternative protein sources that work in nursery diets. These products are highly digestible but often more expensive than soybean meal. They can be useful in diets for pigs with soybean allergies or in organic production systems.

Blood meal, meat and bone meal, and poultry meal are less digestible and less palatable than the protein sources listed above. They are better suited to grow-finish diets. If you use them in nursery diets, keep inclusion low and monitor pig performance closely.

Fats and Oils

Adding fat to nursery diets increases energy density and improves palatability. However, young pigs have limited ability to digest fat, particularly saturated fats. The pancreatic lipase system develops gradually over the first few weeks after weaning.

Choose highly digestible fat sources for nursery diets. Vegetable oils like soybean oil, corn oil, and canola oil are well digested by young pigs. Animal fats like tallow and lard are less digestible and better suited to later phases. Coconut oil is highly digestible and has antimicrobial properties but is expensive.

Typical fat inclusion in nursery diets ranges from 2 to 6 percent. Higher levels can cause loose stools and reduce feed intake. If you add fat, balance the diet carefully to maintain the correct calorie-to-lysine ratio.

Fiber Sources

Fiber is not an energy source for pigs, but it plays important roles in gut health and behavior. Moderate fiber levels in nursery diets reduce the incidence of diarrhea and support the development of the gastrointestinal tract. Fiber also helps pigs feel full and reduces stereotypic behaviors like belly nosing.

Soybean hulls, wheat bran, and beet pulp are common fiber sources for nursery diets. Use them at 2 to 5 percent of the diet. Too much fiber reduces energy density and can decrease growth performance. The goal is to provide enough fiber for gut health without diluting the diet excessively.

Nursery Pig Feed Additives: Functional Ingredients

Feed additives are ingredients added in small amounts to achieve specific effects beyond basic nutrition. They include growth promoters, gut health modifiers, palatability enhancers, and feed quality preservatives. Selecting the right additives depends on your herds health status, facility hygiene, and budget.

Zinc Oxide

Zinc oxide is one of the most studied and widely used additives in nursery pig feed. At pharmacological levels of 2,000 to 3,000 ppm, zinc oxide reduces post-weaning diarrhea and improves growth performance. It works through multiple mechanisms including antimicrobial activity, gut barrier enhancement, and immune modulation.

The benefits of zinc oxide are greatest in the first two weeks after weaning. Most producers include it in the first and second nursery diets, then remove it from the third diet. Some producers use lower levels of 1,500 to 2,000 ppm to reduce cost while maintaining some benefit.

Zinc oxide has come under regulatory scrutiny in some regions due to environmental concerns. High levels of zinc in manure can accumulate in soil and potentially contaminate water sources. The European Union has restricted the use of pharmacological zinc oxide, and other regions may follow. Check your local regulations before using high levels of zinc oxide.

When you use zinc oxide, follow the withdrawal period specified on the product label. Most products require a withdrawal period before slaughter, which is rarely an issue for nursery pigs but matters if you market pigs directly from the nursery phase.

Copper

Copper is another trace mineral with growth-promoting effects at pharmacological levels. Adding copper at 100 to 250 ppm in nursery diets improves growth rate and feed efficiency. Copper works through antimicrobial effects in the gut and by stimulating enzyme systems involved in growth.

Copper sulfate is the most common source, but copper chloride and copper proteinate are also available. Copper proteinate has higher bioavailability, which means you can use lower inclusion levels to achieve the same effect. This reduces the environmental impact of copper in manure.

High copper levels can be toxic if fed for extended periods. The maximum safe level for pigs is about 250 ppm. Above this level, copper accumulates in the liver and can cause toxicity. Follow the product label and your nutritionists recommendations.

Acidifiers

Organic acids like formic acid, citric acid, and fumaric acid are added to nursery diets to lower gastric pH and support digestive enzyme activity. The immature pig stomach produces limited acid, so supplemental acids can improve protein digestion and reduce the growth of pathogenic bacteria.

Acidifiers are most effective in the first nursery diet and in herds with poor hygiene or disease challenges. They are less beneficial in clean facilities with good management. The response to acidifiers varies widely among farms, so test them on your operation before committing to their use.

Typical inclusion rates range from 0.5 to 2 percent of the diet. You can use individual acids or blends. Blends often provide better results than single acids because different acids work in different parts of the digestive tract.

Probiotics

Probiotics are live microorganisms that provide health benefits when consumed in adequate amounts. Common probiotics for pigs include Lactobacillus, Bifidobacterium, Bacillus, and Saccharomyces species. They work by competing with pathogenic bacteria, producing antimicrobial compounds, and modulating the immune system.

The response to probiotics in nursery diets is variable. Some studies show significant improvements in growth and reduced diarrhea, while others show no effect. The variability likely reflects differences in product quality, dosage, and farm conditions. Probiotics are most beneficial in herds with a history of post-weaning diarrhea or in facilities with poor hygiene.

When selecting a probiotic, choose a product with documented efficacy from controlled trials. Look for products that specify the number of colony-forming units per gram and the stability of the organism in feed. Some probiotics are sensitive to heat and pressure during feed manufacturing.

Prebiotics

Prebiotics are non-digestible carbohydrates that promote the growth of beneficial bacteria in the gut. Common prebiotics for pigs include mannan-oligosaccharides, fructo-oligosaccharides, and beta-glucans. They work by providing a food source for beneficial bacteria and by binding to pathogenic bacteria to prevent their attachment to the gut wall.

Prebiotics are more stable than probiotics and easier to incorporate into feed. They are often used in combination with probiotics to provide both a food source and the beneficial organisms. The response to prebiotics is generally more consistent than to probiotics, but still varies among farms.

Mannan-oligosaccharides are the most common prebiotic in nursery diets. They are derived from yeast cell walls and have been shown to reduce Salmonella and E. coli colonization in pigs. Use them at 0.1 to 0.2 percent of the diet.

Enzymes

Exogenous enzymes are added to nursery diets to improve nutrient digestibility. The most common enzymes for swine diets are phytase, which releases phosphorus from phytate, and proteases, which improve protein digestion. Carbohydrases like xylanase and beta-glucanase are less common but can be useful in diets containing wheat or barley.

Phytase is the most cost-effective enzyme for swine diets. It reduces the need for supplemental phosphorus and decreases phosphorus excretion in manure. Most commercial phytase products allow you to reduce dietary phosphorus by 0.1 to 0.15 percent while maintaining performance. This can save significant feed cost over the nursery period.

Proteases are less common than phytase but can improve protein digestibility in diets containing less digestible protein sources. They are most beneficial in diets with high levels of soybean meal or other plant proteins. The response to proteases varies with diet composition and pig age.

Antimicrobial Feed Additives

Antibiotic growth promoters have been used in swine diets for decades to improve growth and prevent disease. However, concerns about antimicrobial resistance have led to restrictions on their use in many regions. In the United States, antibiotic growth promoters are no longer available for use in feed without a veterinary prescription.

If you use antibiotics in nursery feed, you must work with your veterinarian to obtain a prescription and follow all withdrawal periods. Common antibiotics for nursery diets include tiamulin, chlortetracycline, and carbadox. These products are effective against specific pathogens and should be used only when needed.

The future of antimicrobial feed additives is uncertain. Many producers are moving toward antibiotic-free production and relying on the alternatives described above. If you are considering antibiotic-free production, work with your nutritionist to develop a comprehensive gut health program that includes dietary changes, probiotics, and improved hygiene.

Palatability Enhancers

Palatability enhancers are additives that improve feed intake by making the diet more attractive to pigs. They include sweeteners, flavorings, and aroma compounds. These products are most useful in the first nursery diet when pigs are adapting to solid feed.

Milk flavors, vanilla, and fruit flavors are common in nursery diets. Some products combine multiple flavors to create a complex profile. The response to palatability enhancers is variable, but they can be helpful in herds with poor feed intake after weaning.

Sweeteners like saccharin and sucralose are sometimes added to nursery diets. Pigs have a natural preference for sweet tastes, and sweeteners can encourage intake of the first nursery diet. However, the effect diminishes as pigs mature and adapt to feed.

Mycotoxin Binders

Mycotoxins are toxic compounds produced by molds that contaminate feed ingredients. Common mycotoxins in swine feed include aflatoxin, deoxynivalenol, zearalenone, and fumonisin. Mycotoxins reduce feed intake, impair immune function, and can cause reproductive problems.

Mycotoxin binders are clay-based products that bind to mycotoxins in the digestive tract and prevent their absorption. Common binders include bentonite, zeolite, and yeast cell wall products. The effectiveness of binders varies with the type of mycotoxin and the specific product.

The best approach to mycotoxin management is prevention. Test incoming ingredients for mycotoxins and reject contaminated loads. Store feed and ingredients in clean, dry conditions to prevent mold growth. If you find mycotoxins in feed, work with your veterinarian to determine the appropriate response.

Phase Feeding Programs for Nursery Pigs

Nursery pigs have changing nutrient requirements as they grow and their digestive systems mature. Phase feeding involves changing the diet formulation at specific body weights or ages to match these changing requirements. This approach reduces feed cost while maintaining performance.

Phase 1: The First Diet

The first nursery diet, also called the pre-starter or phase 1 diet, is fed from weaning until about 10 to 12 pounds of body weight. This diet is the most complex and expensive because it must support the transition from milk to solid feed.

The phase 1 diet should include highly digestible ingredients like plasma, fish meal, dried whey, and highly processed soybean products. It should contain 20 to 24 percent crude protein and 1.5 to 1.7 percent lysine. The diet should be formulated to be highly palatable to encourage feed intake in the critical first days after weaning.

Feed phase 1 diets for 7 to 10 days after weaning. Some producers feed phase 1 for only 5 to 7 days to reduce cost. The optimal duration depends on pig age at weaning, health status, and the quality of the diet.

Phase 2: The Second Diet

The second nursery diet, or starter diet, is fed from about 12 to 20 pounds of body weight. This diet is less complex than phase 1 but still contains highly digestible ingredients. Plasma and fish meal levels are reduced, and conventional soybean meal can be increased.

The phase 2 diet should contain 20 to 22 percent crude protein and 1.35 to 1.5 percent lysine. Feed phase 2 for 10 to 14 days, depending on pig growth. The goal is to transition pigs gradually to less expensive ingredients while maintaining growth performance.

Phase 3: The Third Diet

The third nursery diet, or grower-starter diet, is fed from about 20 to 35 pounds of body weight. This diet contains conventional soybean meal as the primary protein source and can include a wider range of ingredients.

The phase 3 diet should contain 19 to 21 percent crude protein and 1.25 to 1.35 percent lysine. Feed phase 3 for 14 to 21 days. This diet is significantly less expensive than the earlier phases, which helps reduce overall nursery feed cost.

Phase 4: The Fourth Diet

The fourth nursery diet is optional and is fed from about 35 to 55 to 70 pounds of body weight. This diet is similar to a grow-finish diet and contains conventional soybean meal, corn, and minimal specialty ingredients.

The phase 4 diet should contain 18 to 20 percent crude protein and 1.1 to 1.25 percent lysine. Feed phase 4 until pigs reach the target weight for transfer to grow-finish facilities. Some producers skip phase 4 and move pigs directly to a grow-finish diet at 35 to 40 pounds.

Adjusting Phase Length

The phase lengths described above are starting points. Adjust them based on pig performance, feed cost, and facility constraints. If pigs are growing well and feed intake is good, you can move to the next phase earlier. If pigs are struggling or feed intake is poor, extend the current phase.

Monitor average daily gain and feed intake weekly during the nursery period. Compare your results to breed averages and your own historical data. If pigs are not meeting growth targets, evaluate the diet, environment, and health status to identify the cause.

Formulating Nursery Pig Diets

Nursery diet formulation requires balancing nutrient levels, ingredient costs, and pig requirements. Most producers work with a swine nutritionist to develop diets that meet the specific needs of their operation. However, understanding the formulation process helps you make better decisions and communicate effectively with your nutritionist.

Nutrient Requirements

The National Research Council publishes nutrient requirements for swine, which serve as the foundation for most diet formulations. However, these requirements are minimums for average pigs. Most commercial diets contain nutrient levels above NRC requirements to account for variability in ingredients, feed intake, and environmental conditions.

Key nutrients to monitor in nursery diets include:

• Lysine: The first limiting amino acid in swine diets. Requirements range from 1.5 to 1.7 percent in phase 1 to 1.1 to 1.25 percent in phase 4.
• Other amino acids: Methionine, threonine, and tryptophan are also important. Formulate to meet the ideal amino acid ratio relative to lysine.
• Energy: Metabolizable energy should be 1,450 to 1,550 kcal per pound in phase 1, decreasing slightly in later phases.
• Calcium and phosphorus: These minerals are critical for bone development. Maintain a calcium-to-phosphorus ratio of about 1.2 to 1.4 to 1.
• Vitamins and trace minerals: Include a complete vitamin and mineral premix at the recommended level.

Ingredient Quality Control

The quality of feed ingredients varies among suppliers and over time. Poor-quality ingredients can reduce pig performance and cause health problems. Implement a quality control program that includes:

• Visual inspection of each load of ingredients
• Testing for moisture, protein, and key nutrients
• Testing for mycotoxins, especially in corn and soybean meal
• Checking for foreign material, insects, and mold
• Verifying particle size of processed grains

Work with your feed supplier to establish quality specifications and hold them accountable to those specifications. If you mix feed on-farm, test your finished feed periodically to verify that the formulation was followed correctly.

Feed Processing

The way you process feed affects nutrient digestibility and pig performance. Key processing considerations for nursery diets include:

• Particle size: Grind grains to 600 to 700 microns for optimal digestibility. Finer grinding improves digestibility but can cause stomach ulcers and feed bridging.
• Pelleting: Pelleting nursery diets improves feed efficiency and reduces feed wastage. However, the heat and pressure of pelleting can damage some additives like probiotics and enzymes.
• Mixing: Ensure that feed is mixed thoroughly to distribute additives evenly. Inadequate mixing can lead to nutrient deficiencies or toxicities.

Common Mistakes in Nursery Feed Management

Feeding Grow-Finish Diets to Nursery Pigs

One of the most common and costly mistakes is feeding grow-finish diets to nursery pigs to save money. This approach almost always reduces growth performance and increases the risk of diarrhea and mortality. The digestive system of a nursery pig cannot handle the complex ingredients in grow-finish diets.

Skimping on Phase 1 Diet Quality

The phase 1 diet is the most expensive nursery diet, but it is also the most important. Cutting corners on phase 1 ingredients to save money often leads to poorer overall performance and higher mortality. The cost of a poor phase 1 diet is usually greater than the savings.

Ignoring Feed Intake

Feed intake in the first week after weaning is the strongest predictor of nursery performance. Pigs that eat well in the first week grow better, have fewer health problems, and reach market weight sooner. Monitor feed intake daily and take action if intake is below expectations.

Failing to Adjust Feed Levels

Pigs have different nutrient requirements depending on their age and weight. Feeding the same diet to all nursery pigs regardless of size leads to overfeeding some pigs and underfeeding others. Sort pigs by size and adjust feed levels accordingly.

Not Monitoring Fecal Consistency

Fecal consistency is an early indicator of gut health and diet problems. Loose stools can indicate diarrhea, excessive protein, or poor ingredient digestibility. Monitor fecal consistency daily and investigate any changes.

Overusing Additives

More is not always better when it comes to feed additives. Excessive levels of zinc, copper, or other additives can be toxic or reduce performance. Follow the recommended inclusion levels and work with your nutritionist to determine the right additives for your operation.

Monitoring Nursery Pig Performance

Regular monitoring helps you identify problems early and make informed decisions about diet formulation and management. Key performance indicators for nursery pigs include:

Average Daily Gain

Average daily gain measures how quickly pigs are growing. Calculate it by dividing total weight gain by the number of days in the period. Expected average daily gain for nursery pigs ranges from 0.6 to 1.2 pounds per day, depending on age and genetics.

Weigh a sample of pigs at the start and end of each nursery phase to track growth. Weigh at least 20 to 30 pigs per group to get a reliable estimate. Compare your results to breed averages and your own historical data.

Feed Intake

Feed intake measures how much pigs are eating. Calculate it by dividing total feed consumed by the number of pig-days in the period. Expected feed intake for nursery pigs ranges from 0.5 to 2.5 pounds per day, depending on age.

Monitor feed intake daily using feed scales or feed bin sensors. Sudden drops in feed intake can indicate disease, diet palatability problems, or environmental stress.

Feed Conversion Ratio

Feed conversion ratio measures how efficiently pigs convert feed to gain. Calculate it by dividing total feed consumed by total weight gain. Expected feed conversion for nursery pigs ranges from 1.2 to 1.8 pounds of feed per pound of gain.

Feed conversion is influenced by diet quality, health status, and environmental conditions. Poor feed conversion indicates that pigs are not using feed efficiently, which may indicate digestive problems or disease.

Mortality and Morbidity

Mortality is the percentage of pigs that die during the nursery period. Acceptable mortality for the nursery phase is less than 2 percent. Morbidity is the percentage of pigs that become sick but survive. Monitor both indicators closely and investigate any increase.

Fecal Consistency Score

Fecal consistency scoring is a simple way to monitor gut health. Score feces on a scale of 1 to 5, where 1 is watery diarrhea and 5 is firm, well-formed feces. A score of 4 is ideal. Scores below 3 indicate diarrhea and warrant investigation.

When to Call a Veterinarian or Extension Agent

Most nursery feed problems can be resolved through diet adjustments and management changes. However, some situations require professional assistance. Call your veterinarian if:

• Diarrhea persists for more than three days despite dietary changes
• Mortality exceeds 2 percent in the first week after weaning
• Pigs refuse feed for more than 24 hours
• Multiple pigs show signs of neurological problems, respiratory distress, or other unusual symptoms
• You suspect a feed toxicity or contamination problem
• You are considering the use of antibiotics or other regulated additives

Your veterinarian can help diagnose disease problems, recommend treatment, and advise on feed management. They can also help you develop a herd health program that includes vaccination, biosecurity, and nutrition components.

Extension agents and swine specialists at land-grant universities can provide information on feed ingredient quality, diet formulation, and management practices. They can also help you interpret performance data and make informed decisions about your nursery feeding program.

Frequently Asked Questions

How long should I feed the phase 1 nursery diet?

The phase 1 diet should be fed for 7 to 10 days after weaning. Feed it for the full 10 days if pigs are small, stressed, or in a high-disease environment. You can shorten to 7 days if pigs are large, healthy, and eating well. The key is to ensure pigs are consuming adequate feed before switching to the less expensive phase 2 diet.

Can I reduce zinc oxide levels in nursery feed?

You can reduce zinc oxide levels if your herd has good health and your facility has excellent hygiene. Some producers successfully use 1,500 ppm instead of 2,500 to 3,000 ppm. Start with a trial on a subset of pigs to evaluate the impact on diarrhea and growth before making a herd-wide change. Work with your nutritionist to determine the minimum effective level for your operation.

What is the best protein source for the first nursery diet?

Spray-dried animal plasma is generally considered the best protein source for the first nursery diet because it is highly digestible, palatable, and provides immunoglobulins that support gut health. Fish meal is also excellent. If cost is a concern, use a combination of plasma and fish meal at lower levels, supplemented with highly processed soybean products.

How do I know if my feed ingredients are contaminated with mycotoxins?

The only reliable way to detect mycotoxins is through laboratory testing. Send samples of suspect ingredients to a certified laboratory for analysis. Common tests include ELISA and chromatography methods. Visual inspection is not sufficient because mycotoxins are invisible and can be present even when the grain looks clean.

Should I add probiotics to nursery feed?

Probiotics can be beneficial, especially in herds with a history of post-weaning diarrhea or in facilities with poor hygiene. However, the response varies widely among products and farms. Choose a product with documented efficacy from controlled trials and test it on a subset of pigs before using it herd-wide. Probiotics are not a substitute for good hygiene and management.

How much copper should I add to nursery feed?

Copper is commonly added at 100 to 250 ppm in nursery diets. Levels at the higher end of this range provide growth-promoting effects but increase the environmental impact of manure. Copper proteinate has higher bioavailability than copper sulfate, so you can achieve the same effect with lower inclusion levels. Do not exceed 250 ppm to avoid toxicity.

What particle size should I grind corn to for nursery pigs?

Grind corn to 600 to 700 microns for nursery pigs. This particle size optimizes digestibility while minimizing the risk of stomach ulcers and feed bridging. Finer grinding increases digestibility but can cause gastric problems. Coarser grinding reduces digestibility and increases feed wastage.

When should I switch nursery pigs to a grow-finish diet?

Most producers switch nursery pigs to a grow-finish diet at 55 to 70 pounds of body weight. The exact weight depends on your facility, genetics, and feed program. Some producers use a phase 4 nursery diet from 35 to 55 pounds to ease the transition. The key is to ensure pigs are eating well and growing consistently before making the switch.

Related Farming Guides

This section will be populated with links to related farming guides on swine nutrition, pig health management, and nursery facility design. Check back for updates or explore other resources on this site for more information on raising healthy, productive pigs.

Related Clinical & Scientific Guides

• Pig Enrichment Programs and Behavior Monitoring
• Swine Handling Facility Design for Safe Pig Movement
• 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.