# Wean-to-Finish Pig Production: Facilities, Management, and Economics ## Key Takeaways - Wean-to-finish systems consolidate pig rearing from approximately 5 kg to 135 kg in a single facility, necessitating adaptable pen sizing, adjustable feeders/drinkers, and precise environmental controls (temperature gradients, variable ventilation) to accommodate the wide weight range and mitigate risks of poor air quality (e.g., ammonia < 10 ppm). - All-in/all-out management by barn or room is critical for disease cycle interruption, requiring a minimum 5-7 day downtime for cleaning and disinfection post-marketing, with careful pig movement protocols to minimize stress and disease introduction. - Nutritional management involves phase feeding strategies with diets tailored to specific weight ranges, and the judicious use of reduced crude protein diets supplemented with synthetic amino acids can lower nitrogen excretion and ammonia emissions without compromising growth performance if essential amino acids are balanced. - Health management in single-airspace wean-to-finish barns requires stringent biosecurity measures to prevent rapid spread of diseases like PRRS and swine influenza, with vaccination protocols tailored to regional risks and daily mortality monitoring to identify whole-herd risk factors. - Economically, wean-to-finish systems offer lower initial capital costs per pig place and potentially reduced labor/transport costs compared to multi-site systems, but require careful management of operating costs such as heating and ventilation for diverse pig sizes. - Common failure patterns include high early mortality (often linked to pig quality or temperature management), poor growth performance (due to nutrition, disease, or environment), ventilation failures, and feed wastage, all of which necessitate prompt professional intervention from veterinarians, nutritionists, or engineers. --- Wean-to-Finish Pig Production: Facilities, Management, and Economics Wean-to-finish pig production is a single-site system where pigs are moved directly from the nursery phase to the finishing barn without a second relocation. This approach consolidates the growing period from approximately 21 days of age to market weight in one facility. For producers evaluating this model, the primary considerations involve facility design that accommodates both small and large pigs, pig flow management to maintain all-in/all-out groups, nutritional programs that transition across weight ranges, health protocols that address the risks of a single airspace, and an economic comparison with multi-site systems. This article covers facility design, pig flow, nutrition, health management, and economic comparison with multi-site systems using evidence from peer-reviewed research and official sources. ## At a Glance The table below summarizes key comparisons between wean-to-finish and conventional multi-site production systems. These comparisons are based on published research and practical observations. | Factor | Wean-to-Finish System | Multi-Site System | | --- | --- | --- | | Facility design | Single barn with pens sized for pigs from 5 kg to 135 kg, requires adjustable feeders and drinkers | Separate nursery and finishing barns, each facility is purpose-built for a specific weight range | | Pig flow | One movement from farrowing to market, all-in/all-out by barn or room | Two or more movements, pigs are moved from nursery to finisher, increasing handling stress | | Mortality risk | Mortality patterns are influenced by whole-herd risk factors including facility type and management | Mortality may be affected by transport stress and adaptation to new environments at each move | | Nutritional management | Single feeding program with phase feeding across weight ranges, reduced crude protein diets with synthetic amino acids can be used | Separate nursery and finisher diets, transition between phases requires diet changes at each site | | Economic considerations | Lower capital cost per pig place if one barn is built, potential for reduced labor and transport costs | Higher capital cost for separate facilities, increased labor for moving pigs and cleaning multiple sites | | Environmental emissions | Ammonia and greenhouse gas emissions are influenced by diet composition, particularly the inclusion of dried distillers grains with solubles | Emissions may vary by facility type and management practices | ## Facility Design and Environmental Control ### Barn Layout and Pen Sizing Wean-to-finish barns must accommodate pigs from approximately 5 kg to 135 kg. Pen dimensions should allow for adequate space per pig across the entire growth period. The minimum space allowance for finishing pigs is typically 0.65 to 0.75 square meters per pig, but wean-to-finish pens require a larger initial space per pig to account for the smaller pigs at placement. Adjustable gates or movable panels can be used to create smaller pens for newly weaned pigs and then expanded as pigs grow. Feeders and drinkers must be adjustable in height to remain accessible to pigs of all sizes. Nipple drinkers should be positioned at two heights, or a single adjustable drinker can be used. Flooring must provide adequate traction for small pigs while allowing manure to pass through. Fully slatted floors are common, but partial slats with a solid lying area may be used in colder climates. ### Ventilation and Air Quality Ventilation systems must manage the heat and moisture produced by pigs ranging from 5 kg to 135 kg. The ventilation rate required for a barn full of 135 kg pigs is substantially higher than for a barn full of 5 kg pigs. Variable-speed fans and automated controllers that adjust based on temperature and humidity are essential. Air quality is a critical concern in wean-to-finish barns because pigs are housed in the same airspace for the entire growing period. Ammonia and hydrogen sulfide emissions from wean-to-finish swine barns have been measured, and diet composition influences these emissions. Feeding diets with or without dried distillers grains with solubles (DDGS) affects the levels of ammonia, hydrogen sulfide, and greenhouse gases emitted from the barn. Producers should monitor air quality regularly and adjust ventilation rates to keep ammonia concentrations below 10 ppm. Sound levels in wean-to-finish facilities can also be a welfare concern. Studies have measured sound levels in wean-to-finish facilities, and excessive noise can cause stress and reduce growth performance. Fans, feeders, and pig activity all contribute to noise levels. Using geostatistics to evaluate the environment of wean-to-finish swine housing can help identify areas within the barn that have poor air quality or temperature variation. This spatial analysis allows producers to adjust ventilation inlets or add mixing fans to improve uniformity. ### Temperature Management Newly weaned pigs require a temperature of 28 to 30 degrees Celsius, while finishing pigs are comfortable at 15 to 20 degrees Celsius. Wean-to-finish barns must provide a temperature gradient that allows pigs to choose their preferred microclimate. Zone heating with heat lamps or radiant heaters in the creep area for small pigs is essential. The rest of the barn can be maintained at a lower temperature suitable for larger pigs. Automated controllers should be programmed to gradually reduce the set point temperature over the first four to six weeks after placement. Bedding or insulated pads can be provided in the creep area to help small pigs conserve heat. In hot weather, evaporative cooling pads or sprinklers can be used to reduce heat stress in finishing pigs. ## Pig Flow and All-In/All-Out Management ### Batch Farrowing and Group Sizing Wean-to-finish systems require a consistent supply of weaned pigs to fill each barn or room. Batch farrowing schedules must be aligned with the capacity of the wean-to-finish facility. A typical batch size is the number of pigs weaned from one week of farrowing. The barn or room is filled with pigs from a single source or multiple sources that are health-matched. All-in/all-out management by barn or room is critical to break disease cycles. After a group is marketed, the barn must be completely emptied, cleaned, disinfected, and dried before the next group arrives. The downtime between groups should be at least five to seven days, longer if a disease outbreak occurred. ### Movement and Handling Pigs are moved directly from the farrowing house or nursery to the wean-to-finish barn. This single movement reduces handling stress compared to multi-site systems where pigs are moved twice. However, the initial movement must be done carefully to minimize stress. Pigs should be moved in small groups using sorting boards or paddles. Avoid using electric prods. The transport distance from the farrowing site to the wean-to-finish barn should be as short as possible. If pigs are sourced from multiple farms, they should be mixed only after arrival at the wean-to-finish barn, and mixing should be done in a way that minimizes fighting. Providing enrichment such as hanging toys or straw can reduce aggression during the first few days after mixing. ### Records and Measurements Producers should maintain records for each group of pigs placed in a wean-to-finish barn. Key records include: - Date of placement and source of pigs - Number of pigs placed and average weight - Mortality and culling records by week - Feed delivery and feed disappearance by phase - Medication and vaccination records - Date of marketing and average market weight - Barn cleaning and downtime records These records allow producers to calculate key performance indicators such as average daily gain, [feed conversion ratio](/knowledge/animal-farming/poultry/feed-conversion-ratio-measuring-improving-poultry-efficiency), mortality rate, and days to market. Comparing these indicators across groups and barns helps identify management problems early. ## Nutritional Management ### Phase Feeding Strategies Wean-to-finish pigs require a series of diets that match their changing nutrient requirements. A typical phase feeding program includes a starter diet for the first two to three weeks after weaning, a grower diet for the next four to six weeks, and a finisher diet for the remainder of the growth period. Some producers use additional phases to fine-tune nutrient delivery. The transition between diets should be gradual to avoid feed intake drops. Feeders must be adjustable to accommodate the smaller pigs at the start and the larger pigs at the end. Feeder adjustment is critical to minimize feed wastage and maintain feed intake. ### Reduced Crude Protein Diets Research has examined the effect of reduced crude protein (CP) diets supplemented with synthetic amino acids on growth performance and nutrient excretion in wean-to-finish swine. These diets can reduce nitrogen excretion and ammonia emissions without compromising growth performance if essential amino acids are balanced. Producers considering reduced CP diets should work with a nutritionist to ensure that lysine, methionine, threonine, tryptophan, and valine are supplied at adequate levels. The cost of synthetic amino acids must be weighed against the savings from reduced protein ingredients and potential environmental benefits. ### Feed Form and Processing Pelleted diets are commonly used in wean-to-finish systems because they improve feed conversion and reduce feed wastage compared to meal diets. However, pellets can be more expensive to produce. The pellet quality must be maintained to avoid fines, which reduce intake and increase wastage. Feed particle size should be consistent, typically 600 to 800 microns for finishing pigs. Finer grinding improves digestibility but can increase the risk of gastric ulcers. Feeders should be checked daily to ensure feed is flowing freely and that there is no bridging or clogging. ## Health Management and Biosecurity ### Disease Risks in Single-Airspace Systems Wean-to-finish barns house pigs of the same age group in a single airspace. This design reduces the risk of disease transmission from older pigs to younger pigs, which is a common problem in continuous-flow finishing barns. However, if a disease enters the barn, it can spread rapidly through the entire group because all pigs share the same air. Respiratory diseases such as [porcine reproductive and respiratory syndrome](/knowledge/viruses/general/porcine-reproductive-and-respiratory-syndrome-genomic-surveillance-and-vaccine-strategies-using-bioinformatics) (PRRS) and [swine influenza](/knowledge/veterinary-medicine/clinical-methods/swine-swine-influenza-diagnosis-management) are particular concerns. The impact of the timing of PRRS virus and swine enteric coronaviruses introduction on wean-to-market productivity has been studied. Early introduction of these viruses can significantly reduce growth performance and increase mortality. Producers should implement strict biosecurity protocols to prevent disease introduction. ### Vaccination Protocols Vaccination programs should be tailored to the disease risks on the farm and in the region. A cost-benefit analysis of swine influenza A vaccination in a wean-to-finish production setting in the United States has been conducted. Vaccination can reduce the economic losses associated with influenza outbreaks, but the cost of the vaccine and labor must be considered. Producers should consult with a veterinarian to develop a vaccination schedule that includes core vaccines such as PRRS, mycoplasma, and circovirus, as well as region-specific vaccines. Vaccines should be administered according to the manufacturer's instructions, and records of vaccination dates, batch numbers, and pig identification should be kept. ### Mortality Monitoring and Risk Factors Mortality patterns in commercial wean-to-finish [swine production systems](/knowledge/animal-farming/swine/swine-production-systems-comparing-conventional-organic-and-outdoor-models) have been described in the literature. Mortality is typically highest in the first two weeks after placement and again near market weight. Whole-herd risk factors associated with wean-to-finish mortality under the conditions of a Midwestern USA swine production system have been identified. These risk factors include pig source, weaning age, barn type, and management practices. Producers should monitor mortality daily and investigate any increase above baseline. Post-mortem examinations should be performed on a sample of dead pigs to identify the cause of death. If mortality exceeds 5 percent in a group, a veterinarian should be consulted to investigate and recommend corrective actions. ### Biosecurity Measures Biosecurity is the most important tool for preventing disease in wean-to-finish systems. Key measures include: - Limiting visitor access to the barn - Requiring shower-in/shower-out for all personnel - Providing barn-specific boots and coveralls - Cleaning and disinfecting all equipment before it enters the barn - Controlling rodents, birds, and insects - Using a line of separation between clean and dirty areas - Implementing a downtime policy for personnel who have been to other pig farms Feed trucks and other delivery vehicles should be kept away from the barn entrance. A designated receiving area for feed and supplies should be located at the barn perimeter. Dead pigs should be removed from the barn daily and disposed of properly, either by composting, incineration, or rendering, depending on local regulations. ## Economic Comparison with Multi-Site Systems ### Capital Costs Wean-to-finish systems typically have lower capital costs per pig place than multi-site systems because only one barn is built instead of two. The cost of land, site preparation, and utilities is also lower for a single site. However, the wean-to-finish barn must be larger and more versatile than a dedicated nursery or finisher barn. The cost of adjustable feeders, drinkers, and ventilation systems may be higher than for a standard barn. Producers should obtain quotes from multiple builders and compare the total cost per pig place for a wean-to-finish barn versus separate nursery and finisher barns. ### Operating Costs Operating costs for wean-to-finish systems can be lower than for multi-site systems because there is only one pig movement, which reduces labor and transport costs. Feed costs may be similar if the same feeding program is used. However, wean-to-finish barns may have higher heating costs in the first few weeks after placement because the entire barn must be heated to a temperature suitable for small pigs. In multi-site systems, only the nursery is heated to that temperature. Energy costs for ventilation may also be higher in wean-to-finish barns because the ventilation system must handle a wide range of pig sizes. Producers should track energy costs per pig place and compare them across systems. ### Revenue and Profitability Revenue from wean-to-finish systems is determined by the number of pigs marketed, their average weight, and the market price. Mortality and culling rates directly affect revenue. Productivity analysis of farrow-to-finish swine farms has been conducted, and similar analysis can be applied to wean-to-finish systems. Producers should calculate the cost per pig produced, including feed, labor, utilities, veterinary costs, and depreciation. The break-even market price should be compared to current and projected market prices. If the break-even price is above the market price, the system is not profitable. Producers should also consider the value of manure as a fertilizer, which can offset some costs. ### Risk and Flexibility Wean-to-finish systems are less flexible than multi-site systems because the barn is dedicated to a single group of pigs for the entire growing period. If market prices drop, the producer cannot easily reduce production without leaving the barn empty. Multi-site systems allow producers to adjust the number of pigs in the nursery and finisher independently. However, wean-to-finish systems reduce the risk of disease transmission between age groups, which can improve overall health and reduce mortality. The choice between systems depends on the producer's risk tolerance, capital availability, and management capabilities. ## Common Failure Patterns ### High Early Mortality High mortality in the first two weeks after placement is a common problem in wean-to-finish systems. This is often caused by poor pig quality at weaning, inadequate temperature management, or disease. Producers should ensure that pigs are weaned at an appropriate age and weight, typically at least 21 days of age and 5.5 kg. The barn temperature should be set to 28 to 30 degrees Celsius for the first week, and zone heating should be provided. If mortality exceeds 3 percent in the first week, the cause should be investigated immediately. ### Poor Growth Performance Poor average daily gain and feed conversion can result from inadequate nutrition, poor feed intake, disease, or environmental stress. Feeders should be checked daily to ensure they are functioning properly and that feed is fresh. Water flow rates should be checked to ensure pigs have adequate access to clean water. If growth performance is below target, a nutritionist should review the feeding program. Disease testing may be necessary to rule out subclinical infections. ### Ventilation Failures Ventilation system failures can lead to heat stress, poor air quality, and increased mortality. Backup generators should be installed to maintain ventilation during power outages. Alarms should be set to alert personnel if the temperature in the barn exceeds a set point. Ventilation controllers should be calibrated regularly. If ammonia levels exceed 10 ppm, ventilation rates should be increased, and the manure management system should be checked. ### Feed Wastage Feed wastage is a significant economic loss in wean-to-finish systems. Feeders should be adjusted so that pigs can access feed easily but cannot root it out. The feeder pan should be checked for fines and spoiled feed. Feed wastage can be measured by comparing feed disappearance to expected feed intake based on growth performance. If wastage exceeds 5 percent, feeder adjustment and feed quality should be reviewed. ## Welfare and Safety Context ### Pig Welfare Wean-to-finish systems can provide good welfare if pigs are managed properly. The single movement reduces handling stress, and all-in/all-out management reduces disease pressure. However, the single airspace means that all pigs are exposed to the same environmental conditions, which may not be optimal for all pigs. Providing a temperature gradient and enrichment can improve welfare. Tail biting and other injurious behaviors can occur in wean-to-finish systems, particularly if pigs are overcrowded or under-stimulated. Producers should monitor pigs daily for signs of injury or disease and take corrective action promptly. ### Worker Safety Worker safety in wean-to-finish barns involves risks from manure gases, dust, and moving pigs. Manure pits can produce hydrogen sulfide, which is toxic at high concentrations. Workers should never enter a manure pit without proper respiratory protection and a safety harness. Ventilation should be increased before entering the barn after manure agitation. Dust from feed and bedding can cause respiratory problems. Workers should wear dust masks or respirators when handling feed or cleaning the barn. Moving pigs can cause injuries from kicks, bites, or being knocked over. Workers should use proper handling techniques and wear sturdy boots and gloves. ### [Food Safety](/knowledge/bacteria/livestock-bacteria/cooking-chicken-bacteria-prevention) Food safety in wean-to-finish systems is managed through proper use of medications and vaccines, adherence to withdrawal periods, and good hygiene. All medications should be used according to veterinary prescription and label instructions. Withdrawal periods must be observed to prevent drug residues in meat. Feed should be stored in clean, dry conditions to prevent mold growth and mycotoxin contamination. Pigs should be inspected before slaughter to ensure they are healthy and free from disease. Any pigs that die on farm must be disposed of properly and must not enter the food chain. ## Professional Escalation Criteria Producers should seek professional help from a veterinarian, nutritionist, or agricultural engineer when: - Mortality exceeds 5 percent in a group - Average daily gain is more than 10 percent below target for two consecutive weeks - Feed conversion ratio is more than 10 percent above target - Ammonia levels in the barn exceed 10 ppm despite increased ventilation - A disease outbreak is suspected, and diagnostic testing is needed - A ventilation system failure cannot be resolved with on-farm resources - A structural problem with the barn is identified - A food safety issue is suspected, such as a potential drug residue violation A veterinarian should be consulted for any disease investigation, vaccination program design, or medication protocol. A nutritionist should be consulted for diet formulation, particularly when using reduced crude protein diets or alternative ingredients. An agricultural engineer should be consulted for ventilation system design, manure management, and barn renovation. ## Frequently Asked Questions ### What is the ideal weaning age for a wean-to-finish system? The ideal weaning age is typically 21 to 28 days. Pigs weaned at a younger age require more intensive management and higher temperatures in the wean-to-finish barn. Pigs weaned at an older age are more robust and have a lower risk of early mortality. Producers should wean at an age that aligns with their farrowing schedule and the capacity of their wean-to-finish facility. ### How much space does each pig need in a wean-to-finish barn? Space requirements vary by pig weight. For pigs from 5 to 30 kg, 0.3 to 0.4 square meters per pig is adequate. For pigs from 30 to 70 kg, 0.5 to 0.6 square meters per pig is needed. For pigs from 70 to 135 kg, 0.65 to 0.75 square meters per pig is required. Pens should be sized based on the final weight of the pigs, and adjustable partitions can be used to provide more space for smaller pigs early in the growth period. ### What are the main advantages of a wean-to-finish system over a multi-site system? The main advantages are reduced pig movement, lower capital costs per pig place, and reduced risk of disease transmission between age groups. Pigs are moved only once from the farrowing house to the wean-to-finish barn, which reduces handling stress and labor. The single-site design also simplifies biosecurity because there is only one barn to manage. ### What are the main disadvantages of a wean-to-finish system? The main disadvantages are the challenge of managing a wide range of pig sizes in one barn, the need for adjustable feeders and drinkers, and the higher heating costs in the first few weeks after placement. The single airspace also means that if a disease enters the barn, it can spread rapidly through the entire group. ### How do I manage temperature for both small and large pigs in the same barn? Zone heating is the most effective approach. Provide heat lamps or radiant heaters in a creep area for small pigs. The rest of the barn can be maintained at a lower temperature suitable for larger pigs. Automated controllers should be programmed to gradually reduce the set point temperature over the first four to six weeks after placement. ### What records should I keep for a wean-to-finish group? Key records include date of placement, number of pigs placed, average weight, mortality and culling records by week, feed delivery and feed disappearance by phase, medication and vaccination records, date of marketing, average market weight, and barn cleaning and downtime records. These records allow you to calculate performance indicators and identify problems early. ### How do I reduce ammonia levels in a wean-to-finish barn? Ammonia levels can be reduced by increasing ventilation rates, managing manure pits to prevent buildup, and using reduced crude protein diets supplemented with synthetic amino acids. Diet composition, particularly the inclusion of DDGS, influences ammonia emissions. Regular monitoring of ammonia levels is essential to ensure they stay below 10 ppm. ### When should I call a veterinarian for a wean-to-finish group? Call a veterinarian if mortality exceeds 5 percent in a group, if average daily gain is more than 10 percent below target for two consecutive weeks, if a disease outbreak is suspected, or if you need help designing a vaccination or medication protocol. Early intervention can prevent small problems from becoming large losses. ## Related Farming Guides - [Manure Management For Pig Farms](/knowledge/animal-farming/swine/manure-management-for-pig-farms) - [Genetic Flow](/blog/guides/genetic-drift-definition-biology) - [Lentivirus Production](/blog/guides/plaque-assays-planning-controls-and-reporting-viral-titer) - [Systems Biology](/blog/news/systems-biology) - [Pig Lameness Monitoring And Flooring Management](/knowledge/animal-farming/swine/pig-lameness-monitoring-and-flooring-management) ## 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 and Further Reading - [www.ars.usda.gov](https://www.ars.usda.gov/animal-production-and-protection) - [www.aphis.usda.gov](https://www.aphis.usda.gov/livestock-poultry-disease/swine) - [www.merckvetmanual.com](https://www.merckvetmanual.com/management-and-nutrition) - [Mortality Patterns in a Commercial Wean-To Finish Swine Production System.](https://pubmed.ncbi.nlm.nih.gov/31146411). Veterinary sciences, 2019. - [Whole-herd risk factors associated with wean-to-finish mortality under the conditions of a Midwestern USA swine production system.](https://pubmed.ncbi.nlm.nih.gov/34801793). Preventive [veterinary medicine](/blog/careers/veterinary-medicine-careers-from-clinical-practice-to-public-health), 2022. - [The effect of reduced CP, synthetic amino acid supplemented diets on growth performance and nutrient excretion in wean to Finish swine.](https://pubmed.ncbi.nlm.nih.gov/35275195). Journal of animal science, 2022. - [The impact of the timing of PRRSV and swine enteric coronaviruses introduction on wean-to-market productivity.](https://pubmed.ncbi.nlm.nih.gov/41092509). Preventive veterinary medicine, 2026. - [Productivity analysis of 70 farrow-to-finish swine farms in Japan from 2013 to 2018.](https://pubmed.ncbi.nlm.nih.gov/35473798). The Journal of veterinary medical science, 2022. - [Effect of wean-to-finish management on pig performance.](https://pubmed.ncbi.nlm.nih.gov/11881920). Journal of animal science, 2002. - [Cost-benefit analysis of swine influenza a vaccination in wean-to-finish production setting in the United States](https://doi.org/10.1016/j.prevetmed.2026.106806). Preventive Veterinary Medicine, 2026. - [Ammonia, hydrogen sulfide, and greenhouse gas emissions from wean-to-finish swine barns fed diets with or without DDGS](https://api.elsevier.com/content/abstract/scopus_id/81255195280). American Society of Agricultural and Biological Engineers Annual International Meeting 2011 Asabe 2011, 2011. - [Sound levels in a wean-to-finish facility in Brazil](https://api.elsevier.com/content/abstract/scopus_id/84878275732). Asabe 9th International Livestock Environment Symposium 2012 Iles 2012, 2012. - [Using geostatistics to evaluate the environment of "wean to finish" swine housing](https://doi.org/10.1590/s0100-69162014000500001). Engenharia Agricola, 2014. > This article is educational and is not a substitute for veterinary diagnosis, treatment, public-health guidance, or regulatory reporting.