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Pork Production: Operations
Table of Contents
Background and Overview
Best Management Practices
Environmental Impacts
Building an EMS
Alternative Technologies
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The main goal of any pork producer is to have an operation that preserves the natural environment while encouraging a healthy animal herd to thrive at a minimal cost. Pork production combines many complex processes to produce lean and marketable livestock. This section provides an overview of those operations that work together to produce a safe and marketable product.

Animal Feeding Operations
Pork Production Phases
Nutritional Inputs
Animal Housing Systems
Common Manure-Handling Systems

Animal Feeding Operations

EPA rules affecting animal feeding operations (AFOs) originated with the 1972 Federal Clean Water Act (CWA). Section 502 of the CWA defined "feedlots" as point sources of water pollution. The federal permit program, National Pollutant Discharge Elimination System (NPDES) permit, was created for point sources that discharge directly into "waters of the United States." EPA regulations resulting from the 1972 CWA were focused around the issue of surface water protection, and the rules developed surrounding the "feedlots" point source category were no exception. This rule addressed the design/operating criteria and in 1976 concentrated animal feeding operations (CAFOs) became subject to the NPDES permit program. Since the mid-1970s, CAFOs have been regulated by federal rule through the NPDES or equivalent state permits.

In 1976, EPA constituted what an AFO and CAFO (a smaller subgroup within AFOs) were as well as which CAFOs (point source) required an NPDES permit. An AFO includes animals fed or maintained for 45 or more days/year within a place of confinement that was marked by an absence of vegetation during a normal growing season. Defining an AFO as a CAFO involves having a sufficient number of animals to warrant regulation under NPDES. The size requirement for swine operations to be subject to the CAFO rules is 2,500 head (55 pounds or more). Although some animal confinement operations are required to obtain a NPDES permit, it should be noted that animal waste is land applied at agronomic rates on approved crops. There are no specific discharge methods for waste to leave the lagoon except for land application therefore animal options represent a unique situation in the NPDES permitting arena. Refer to EPA's Compliance Assistance Sector Notebook for the Agriculture Industry at http://www.epa.gov/compliance/resources/publications/assistance/sectors/notebooks/ls1.pdf for specific AFO/CAFO size determinations.

In 2003, EPA published revisions to its Clean Water Act regulations for CAFOs. EPA also produced a compliance guidance document to help owners and operators of CAFOs understand and comply with the revised regulations. This assistance tool is available at http://cfpub.epa.gov/npdes/afo/compliance.cfm.

2nd Circuit Court ruling on CAFOs and NPDES permitting:

EPA proposed to extend certain compliance dates in the NPDES permitting requirements (40 CFR part 122) and Effluent Limitations Guidelines and Standards (ELGs) (40 CFR part 412) for CAFOs in conjunction with EPA's efforts to respond to the order issued by the Second Circuit Court of Appeals in Waterkeeper Alliance et al. v. EPA, 399 F.3d 486 (2nd Cir. 2005). The purpose of the proposed rule is to address timing issues associated with the Agency's response to the Waterkeeper decision. The proposal would revise dates established in the 2003 CAFO rule, issued on February 12, 2003, by which facilities newly defined as CAFOs were required to seek permit coverage and by which all CAFOs were required to have nutrient management plans (NMPs) developed and implemented. EPA proposed to extend the date by which operations defined as CAFOs as of April 14, 2003, who were not defined as CAFOs prior to that date, must seek NPDES permit coverage, from February 13, 2006, to March 30, 2007. EPA is also proposing to amend the date by which operations that become defined as CAFOs after April 14, 2003, due to operational changes that not have made them a CAFO prior to April 14, 2003, and that are not new sources, must seek would NPDES permit coverage, from April 13, 2006, to March 30, 2007. Finally, EPA proposed to extend the deadline by which CAFOs are required to develop and implement NMPs, from December 31, 2006, to March 30, 2007. This proposal would revise all references to the date by which NMPs must be developed and implemented currently in the 2003 CAFO rule. EPA will also be issuing a proposed rule to revise the 2003 CAFO regulations more broadly in order to address the Second Circuit Court of Appeals decision in a subsequent Federal Register Notice, which the Agency plans to propose for public comment in early 2006. For more information refer to http://www.epa.gov/fedrgstr/EPA-WATER/2005/December/Day-21/w24303.htm.

Pork Production Phases

The following describes the four major phases in pork production:


The production of pork begins with breeding of the sow, the female hog. This can be accomplished by placing a boar, the male hog, in the pen with the sow(s) as typically done in a pasture system. This approach, called pen mating, requires little labor but does not provide exact information about when or if the sow actually bred. Hand mating is the preferred method in controlled-environment facilities. This method involves placing the boar with one sow in an enclosed pen and observing whether mating takes place. This takes more time and labor than pen mating, but it provides exact information to base future management decisions on.

Artificial insemination (AI), is the breeding method of choice on most farms today. AI is preferred for its ability to improve genetic material to be introduced faster while reduces the risk of disease transmission. AI is of particular importance in controlled-environment systems where breeding efficiency has a direct correlation to profitability. AI does not require a breeding boar to be on site, but it does entail the highest level of management expertise and labor out of all the alternative mating options. Once the sow is bred, she gestates for 113 to 116 days before the piglets are farrowed, or born.

Sows can be housed in groups in pastures as well as controlled-environment buildings, or in individual pens in controlled-environment buildings during their breeding and 114-day gestation. Boars are kept in similar ways to that of sows. In order to prevent reduced litter size and piglet death, every effort is made to keep the boars and sows as comfortable as possible to avoid any unnecessary stress.

Farrowing: farrowing

Just before giving birth or farrowing, sows are typically transferred to a farrowing area. Farrowing facilities range from pasture systems with small, individual sow huts to enclosed farrowing houses. The houses may be part of either partial or total controlled-environment operations. Farrowing houses are equipped with individual farrowing pens, stalls, or crates designed to provide a fairly comfortable area for the sow to farrow, as well as to protect the newborn pigs and workers. By limiting her movement, these areas minimize the sow crushing piglets as well as protect the sow and worker when her protective instincts cause her to act aggressively. The baby pigs spend most of their time in a creep area on either side of their mother, where they have feeding access but are protected from being crushed when she lies down. A small percentage of farrowing operations use larger pens with deep straw bedding on solid floors. This method is more labor intensive and often results in more crushing losses. Farrowing buildings are thoroughly cleaned and disinfected before sows enter, and farrowing pastures are rotated to control disease. For more information on best management practices and examples of daily checklists to ensure healthy animals, go to the animal environmental section of Best Management Practices.

Sows typically farrow 9-10 pigs per litter, with a range of 6-13. In 2001, the average number of pigs weaned was 8.8 per litter. Piglets weigh about three pounds at birth and are weaned from the sow at anytime from five days to four weeks. The average sow typically raises between three and five litters of pigs in her lifetime. Sows can be culled and sent to market for various reasons including age, health problems, failure to conceive, or failure to raise a significant number of pigs per litter.

It is imperative to keep a close eye on the baby pigs to ensure that mortality is kept at a minimum while assuring rapid early growth and development. The highest death rate for the entire pork production process occurs within three or four days of birth. These losses are quite costly. It may cost a producer between $380 and $400 a year to keep a sow alive and vital. If she raises 16 pigs during that year, the cost per pig is between $23 and $25. However, if she raises 20 pigs per year, the cost per pig is only $19-$20.

A producer will go to great lengths to ensure his pigs stay healthy to minimize the death rate, which eliminates cuts into his profit. Newborn piglets require large amounts of attention because they are born with little stored energy, cannot regulate their body temperature very efficiently, and can be injured easily by the sow. It is quite common after birth for certain procedures to be preformed on the piglets to foster a high survival rate as well as prevent future problems. Procedures can include disinfecting navels to prevent infections, giving supplemental iron to improve the blood's oxygen-carrying capacity, and castrating boars to prevent less-desirable tasting meat. In addition, pigs are born with razor-sharp teeth and curly tails. To prevent injury to one another and to the sow's udder, the tips of the teeth are clipped at birth. Also, the tail is docked to prevent tail biting.

Nursery: nursery

It is typically to wean the pigs at 3-4 weeks when they weigh anywhere between 10-15 pounds. At this time, they may be moved to a nursery or a grower. A nursery provides a temperature-controlled environment with slotted floors typically constructed of plastic or plastic-coated steel as opposed to concrete to provide a more comfortable setting for the pigs. Also, because of new technology, it is now accepted in the pork production industry to move them to a finishing building retrofitted to accommodate the needs of growing pigs.

Each pig has about three square feet of living space and a readily available source of water and feed. The majority of housing for newly weaned pigs contains completely slotted floors (made of comfortable, and easily cleaned and maintained materials) to allow for all the waste to fall into a holding pit or gutter. This makes it easier to uphold the pig's comfort level and productivity by keeping the floors drier and cleaner. The floors are normally elevated 8-12 inches to minimize the possibility of cold floor drafts chilling the young pigs. Because chilling can be so detrimental to the young pigs, the temperature may be as high as 85 F once the pigs are weaned. The temperature is then gradually dropped to around 70 F as the pigs grow. The nursery rooms are almost always heated with furnaces and ventilated with mechanical fans. In addition, they are controlled by thermostat to ensure the pigs are kept warm and dry throughout the year. For more information on best management practices for hog house design, go to the animal environmental section of Best Management Practices.

At 8-10 weeks of age or as early as six weeks and 40-60 pounds, the pigs are moved to the grow-finishing building.

Grow-Finishing: finishing

It was once thought that growing and finishing were distinct phases in the pork production process. The terminology difference dates back to the time when fat was more valuable and "finishing" pigs meant they were fed to a specific degree of fatness. Oddly enough, growing pigs (up to 120 pounds) and finishing pigs (120 pounds to market weight) were kept in separate pens or even housed in separate buildings.

For the grow-finish phase of pork production, either pasture or controlled-environment facilities can be used. There are five general types of buildings commonly used.


  • Totally enclosed, controlled environment: typically the most costly but provides the greatest control over temperature and humidity. Electric fans provide ventilation.
  • Open floor with outside apron: construction cost is less than other types but because of one side always being open (normally the south side), pigs are always exposed to temperature variation that may reduce comfort and overall performance.
  • Modified open front: so-named because one side, generally the south, is typically opened for summer ventilation and completely closed during the winter. This building type depends on convective currents of air for natural ventilation.
  • Double-curtain buildings: automatically controlled curtains on both sidewalls are routinely placed perpendicular to prevailing winds. To maintain proper temperatures and provide fresh air, a combination of mechanical and natural ventilation is used. These buildings have been a major technological development in pork production. To be cost-competitive, these buildings must usually hold at least 800 pigs per "all-in, all-out" group.
  • Hoop buildings: wooden or concrete sidewalls that are three to four feet high and hold mounted hoops which support covers made of specially treated fabric or plastic. Straw or cornstalks are used for bedding over dirt floors. Research supports that these buildings can provide cost-competitive "all-in, all-out finishing facilities" for as few as 200 pigs per group.

During this final phase of the pigs' production, the pig is fed as much feed as it wants until it reach's a market weight of 250 to 275 pounds. During this phase, each pig is provided with around eight square feet of space. The pigs are typically sent to market at around five to six months of age. Genetics and disease encounters are the main factor in determining market age.

Animals in the finishing houses are much larger and therefore generate a great deal of heat. In general it is more important to provide ventilation to keep the animals cool in the summer as opposed to providing heat in the winter. Animals of this size normally grow best at a temperature of 60-70 degrees. To protect from potentially dangerous cold winter winds, they are kept in a moderately well insulated building. Also, to remove moisture and provide fresh air for the animals, ventilation is a necessity. During the summer, large sidewall vents are opened or large ventilation fans are in operation to maintain a required comfort level for the pigs. Two types of barn ventilation methods are as follows: naturally ventilated with air change due to wind and mechanically ventilated by air drawn into buildings through vents due to negative pressure created with wall fans that exhaust inside air.

Nutritional Inputs

Animal Feeding: Feed is the major production input to the pork production process accounting for more than 65 percent of all production expenses. The average whole-herd feed conversion ratio (pounds of feed required per pound of live weight produced) for the U.S. pork industry is about 3.6-3.8 and is improving steadily (i.e., getting lower, for both boars and sows). For a note of comparison, beef cattle take 7-10 pounds of feed to produce a pound of live weight and a broiler chicken requires about two pounds of feed per pound of live weight produced. The best swineherds in the United States have a whole-herd feed conversion ratio under three pounds.

To raise a hog to market weight, it takes nearly 1,000 pounds of feed. Additionally, about one-and-a-half to two gallons of water per day are consumed over the six-month life of the hog to maintain a healthy, satisfied animal. For more information on best management practices for feed management, refer to the feed management section of Best Management Practices.

Swine's digestive systems are similar to that of humans and differ from other farm animals such as cattle and sheep that eat forage and grass. A pig's diet consists mostly of ground corn to supply heat and energy, and soybean meal to provide the necessary protein as well as vitamins and minerals. A variety of feed ingredients are used in accurate proportions to produce a properly balanced diet for pigs at each stage of life. Young pigs usually are fed a diet with 20-22 percent crude protein. Once the pig reaches a pre-determined weight, diets are changed in order to balance the appropriate amounts of nutrients the pigs consume with what they actually need. This balance reduces the amount of nutrients excreted, while improving growth and performance. As the pig grows, the ration is typically changed to provide more energy and less protein. The overall goal for the producer is to optimize feed utilization for the various stages of growth. Once pigs reach the finishing stage, they are consuming a 13-15 percent crude protein diet. Concentrations of other necessary nutrients are changed in a similar fashion. For a pig-production mass-balance graphic demonstrating how much energy is required to raise a pig, refer to the Environmental Impacts section.

With nutritional needs being different for male and female grow-finisher pigs, many larger operations may modify the rations even further according to the gender of the animal. Recent studies indicate that ration modifications can actually reduce the amount of nitrogen and phosphorous excreted in the manure, while maintaining optimal pig growth and health.

Animal Watering: Watering involves the operation and maintenance of animal drinking systems or access to naturally occurring surface waters or man-made watering structures (e.g., ponds, reservoirs). It is essential that a constant or on-demand supply of water be provided for livestock.

For those housed in other types of confined areas, there are many different types of man-made watering devices, each of which can be modified depending on the animal using the system. Some of the most commonly used systems include the following:

  • Animal-operated pumps or drinkers. Large livestock kept in enclosed and partially enclosed housing can use animal-operated pumps or valves (nose pumps/valves). Livestock-operated, on-demand watering devices allow the animal to use its nose to actuate a valve or push a pendulum unit that dispenses water. Small livestock kept in enclosed housing generally have on-demand drinkers actuated by the mouth or beak of the livestock.
  • Trough systems. Large livestock kept in enclosed and partially enclosed housing can also use trough systems. In trough systems, animals drink directly from troughs or tanks. The discharge of water to the trough/tank may be float-controlled or continuous.

Animal Housing Systems

Before the 1960s, most pork in the United States was raised in outside lots or on pasture systems. With the development of slotted floors and liquid manure-handling systems, it became possible for producers to more easily care for a large number of animals while providing protection from the weather. While protecting animals from the elements, it also minimized potential pollution from lot runoff and predator encounters. In addition, it was more practical to farrow sows twice a year rather than just once. This was the beginning of intensive production schedules on relatively small plots of land currently found worldwide today.

System approaches dominate pork production regardless of whether pigs are raised in pasture or in totally enclosed barns. Regardless of the facility type, repeatable methods and specialization characterize the modern pork producer. Deciding on the type of facility depends largely on a balance of capital investment, labor requirement, and management expertise, while taking into consideration the worker and animal welfare. Effective swine care is more a result of the producer's ability to manage housing than the actual type of housing chosen.

Controlled-environment buildings make handling hogs easier, provide for more direct animal observation, allow for greater production process control, protect animals and workers from the elements and usually result in faster growth-to-market weight and better feed efficiency. However, these buildings require much higher investment but lower labor per unit of output. Most controlled-environment facilities are operated in an "all-in, all-out" fashion.

"All-in, All-out" systems:

Most swine are raised in "all-in, all-out" (AIAO) systems today as mentioned above. This is a system where each room or building is completely emptied and sanitized between pig groups. All new pig groups enter into a freshly cleaned and disinfected environment and stay there for this phase of their life. The building has separate rooms or buildings for each group of pigs weaned, with extra space if needed to allow workers necessary time to clean rooms before the next group of pigs enter. Pigs in AIAO houses are placed in rooms where they are of uniform age and size. They are also isolated to every extent possible to decrease disease-spreading possibilities from older animal groups to younger ones.


  •          disease spread can be better contained
  •          animals are less stressed because they remain with the same age and social group throughout their development
  •          complete cleaning and disinfection between groups is possible


  •          space is less efficiently allocated
  •          more space is needed to allow rooms to be emptied for cleaning between groups

Continuous-flow barn:

In a continuous-flow barn, animals of different developmental stages may be housed in close proximity to one another while the facilities are never empty.


  •          space efficiently used because pigs can be moved to larger pens as they grow, while new arrivals replace them in smaller pens
  •          simple to plan; if producer wants to wean two litters each week, two sows must be bred each week


  •          different ages of animals (with different degrees of disease resistance) are housed together increasing odds of spreading disease
  •          stress levels can be heightened with changing social groups
  •          adequate cleaning and disinfecting are not feasible
  •          higher level of antibiotics and other medications are normally required to control disease

Although less common than the controlled-environment operations, pasture or outdoor production systems are sometimes used. These systems involve more acres of land as well as more labor per unit of output. Outdoor production systems typically require a lower capital investment, especially when less desirable land is used. However, the productivity is usually lower in terms of output per unit of land or labor or feed. These systems have become more popular in recent years as "systems" ideas have been imported from Europe. Also, niche markets promoting free range or organic meat have encouraged a need for more pasture-raised pigs. As a result, a well-managed pasture system can be cost competitive with the controlled-environment operations.

Up until the 1990s, swine production systems were usually housed on a single lot in order to save labor costs and provide convenience. Currently, most swine operations house various production phases at different sites to further minimize contact between pigs of different ages due to health concerns. This can entail either a two-site or three-site system. The two-site system has the breeding and gestation at one location with the farrowing/nursery and grow-finish pigs at a separate site. A three-site system is the same as the two-site with the exception of placing the nursery at an additional site.

Over the past few years, some producers have combined the nursery and grow-finish phases of production where the pigs go to barns immediately after weaning and stay until it is time to go to market. These houses are called "wean-to-finish" barns. These barns provide a substantial amount of additional space per pig than is initially needed, but make it possible to only move the pigs once during their lifetime. This advantage reduces animal stress and saves labor since buildings are not cleaned until the hogs go to market. In the end, the facility type does not change the overall goal of the producer: to provide the proper environment to maximize the welfare and productivity of both animal and worker. For more information on best management practices for facility grounds maintenance and information for determining location of houses, refer to the facility grounds section of Best Management Practices.

Common Manure-Handling Systems

Manure is by far the largest co-product of pig production. It can be handled as either a solid or liquid form depending on the building type used at the facility. When handled properly and applied at agronomic rates, manure can be a vital asset to swine operations because of its ability to provide needed nutrients to crops as opposed to purchasing commercial fertilizer. For more information on best management practices for land application, refer to the land application section of Best Management Practices.

Solid Manure:

Historically, swine manure was handled as a solid. It would either be directly deposited by the grazing animal or collected in some type of appropriate bedding placed on solid-shelter floors to absorb the urine. Typically, manure deposited on solid floors is stored where it lands, while more bedding is added to ensure a dry floor is maintained. When animals are located on an outside lot, liquid must be collected from the dropped manure leaving the solid behind. Subsequently, the manure then composts in place to a certain degree and is removed every few months. The removed manure has added value as fertilizer by spreading it on cropland to close the nutrient cycle. The solid manure is normally surfaced-applied, but in some cases may be incorporated into the soil with a farm tillage system immediately following spreading. In addition, composting is another option for solid-manure management. For more information on manure composting, refer to the composting section of Alternative Technologies.

Lot Runoff:

When outside lots are used, the manure will typically be scraped from the lots every week or two where it is then stacked until it can be hauled to cropland. It is imperative to maintain the outside lot relatively free of manure to control odor and keep runoff water clean for cropland irrigation. It may be possible to divert runoff from small operations directly to pastureland or to a vegetative filter strip where it can infiltrate into the ground. However, it is necessary to prevent any runoff from outside lots from entering into waterways. Clean water from other sources such as roof runoff must be diverted away from the open lot to minimize the amount of wastewater that is treated with animal waste.

Liquid Manure:

The majority of swine manure within the United States is handled as liquid. The animal waste will fall through slotted floors into gutters or concrete storage pits. Slot size depends on the size and age of the hog. Storage pits provide between three and 12 months of storage for the manure. The pits are normally located directly beneath the slotted floors, four to 10 feet deep. In other operations, animal waste falls into shallow pits or gutters that are periodically pumped, flushed or drained to a large outside storage unit. The outside storage may either be built into the earth or in a commercial steel or concrete storage unit. Storage size is dictated by regulatory facilities in most states according to operation size. Units are usually sized large enough to handle six month's accumulation in the Midwestern states to avoid the need to apply manure during the crop growing season and when weather conditions are not conducive to apply waste. This would typically include frozen ground or soil that is too wet and heavy application vehicles that could compact and damage the soil for crop production.

Liquid manure from the appropriate storage unit is normally agitated thoroughly to ensure the manure nutrient content is uniform between loads. It is then hauled to fields for application in large tanker wagons or trucks. Liquid manure is either applied to the soil surface or is incorporated during or shortly after application to control odor and loss of volatile ammonia. Incorporation is a very effective method for controlling nutrient-rich manure runoff and reducing odor from land application if done during or immediately following application. One method of incorporation is a soil injector where liquid manure is physically injected directly into the soil to a depth of six to nine inches as the tanker carrying the manure passes through the field. The immediate contact of manure and soil results in a highly effective method for controlling odor.

In certain remote areas, liquid manure may be pumped to the land application site where it can be irrigated directly onto cropland. In regards to speed and labor efforts, spray-irrigating liquid manure is a very effective land-application method. However, odor issues can be significant especially in populated areas. For more information on best management practices for odor management, refer to the odor-control section of Best Management Practices.


Lagoons are operated to encourage anaerobic digestion of organic material while it is being stored as opposed to storage only. The treated manure has reduced odor when applied. A properly designed and operated treatment lagoon is much larger and more expensive to maintain than a liquid-manure storage system with the same storage time. In addition, organic solids are much less concentrated in the liquid of a lagoon.

In the Midwest, an equal part of relatively clean dilution water must be added for each part of manure sent to the system. To avoid an upset to the biological treatment system that can result in a release of odors, manure must be added slowly and uniformly to the lagoon. This is typically completed by using shallow pits or gutters under slotted floors inside the house to drain or flush manure to the lagoon on a frequent basis, usually every three days to three weeks. To get the manure from the pits to the lagoon, a plug is pulled in the bottom of the pit, called a gravity drain, and a scraper system running under the floor is then used through a process called a "hairpen" gutter. Another common method to flush manure into the lagoon is recirculating a volume of relatively clean effluent water back into the building. This recirculation process involves either a flushing action that takes place several times a day or a "pit-recharge" system that works similar to a toilet being flushed every few days.

A "minimum-design volume" or a predetermined amount must be left in the lagoon after effluent is pumped to the land to ensure a large number of microbial organisms remain to treat the new manure entering the system. For a couple of weeks in the fall of the year, there is an "overturning" of the lagoon contents despite proper operation and maintenance. This is a result of an ambient temperature drop that causes the top layer of lagoon liquid to cool. Subsequently, as the density increases, the cooled top layer "overturns" or drops to the bottom of the lagoon, forcing the bottom layer containing partially digested manure solids, called sludge, to the top. This phenomenon results in a higher odor level around the lagoon for about two weeks. A series of multiple lagoons normally emit fewer odors than single-cell lagoons. For more information on waste management systems BMPs, refer to the waste management practices section of Best Management Practices.

To move the effluent from the lagoon to cropland, spray irrigation systems are the typical delivery method. If the lagoon system is properly maintained and operated, minimum odor should be released during spray irrigation because most of the organic solids have been biologically degraded. In a well-operated lagoon, normal effluent contains less nutrients than the raw sewage because treatment and sedimentation of solids to the bottom of the lagoon. The reduced amounts are as follows: 20 percent less nitrogen and 30-40 percent less phosphorous and potassium. Although there is a reduced amount of P and K in the irrigated effluent, it is not actually "lost." It accumulates in the sludge and must be properly utilized when removed. It is often recommended to remove these solids, or sludge, every few years. If it is necessary to remove the sludge, the operation should plan to handle it as part of its nutrient management plan. For more information on nutrient management plans, please refer to the nutrient management section of Best Management Practices.

With the sludge being more concentrated, it is often more practical to haul it off site to other cropland to better utilize the nutrients contained in the solids. If possible, the sludge should be incorporated as liquid manure because of the nuisance potential of this partially stabilized material.


Biosecurity consists of the procedures used to prevent the spread of animal diseases from one facility to another. Animal diseases can enter a facility through new animals, equipment, and people. Animals, equipment, and people that have recently been at another facility may pose the greatest biosecurity risk. Biosecurity procedures include general categories such as the use of protective clothing, waiting periods for new animals and visitors, and cleaning houses.

Biosecurity is important to livestock owners because some diseases can weaken or kill large numbers of animals at an infected facility. In some cases, the only remedy available to an operation is to sacrifice an entire group of animals in order to prevent the spread of the disease to other parts of the facility or to other facilities. A failure to conduct biosecurity procedures can cause serious financial and productivity losses for a livestock operation.

The types of biosecurity procedures necessary will depend on the type of animals at a facility, the way the diseases of concern spread to and infect animals, and vulnerability of the animals to each specific disease. For example, if a group of swine has little immunity to a serious virus, and that virus can enter the facility on the skin or clothing of visitors, a facility

should require visitors to observe a waiting period, take a shower and change into clean clothing provided by the facility before entering. A different group of swine may have better immunity to the virus and such biosecurity measures would be unnecessary.

Some of the general types of biosecurity procedures include the following:

  • controls on the introduction of new animals to a group or facility (such as quarantine periods).
  • controls on equipment entering the farm (such as washing and disinfecting crates).
  • controls on personnel entering the farm (such as requiring service personnel to stay out of animal buildings or providing protective clothing and footwear).
  • controls on wild or domestic animal access (such as closing holes in buildings to keep undesirable animals out).
  • sanitation in animal housing areas (such as cleaning pens).
  • identification and segregation of sick animals (including adequate removal and disposal of dead animals).

The key to developing adequate biosecurity procedures is to find accurate information about animal diseases and how to prevent them. Potential sources for specific biosecurity information and recommendations include extension services and other agricultural education organizations; veterinarians and veterinary organizations; producer and industry groups; and published information in books, magazines, and World Wide Web sources.


The Topic Hub™ is a product of the Pollution Prevention Resource Exchange (P2Rx)

The Pork Production Topic Hub™ was developed by:

Pollution Prevention Resource Exchange
Pollution Prevention Resource Exchange
Contact email: abray@newmoa.org

Hub Last Updated: 3/18/2009