In this section of the Blueprint, we will concentrate on important management technologies that should be a part of the farrowing staff’s training program.
In recent years, the goal of many sow units has been to achieve the elusive 30 pigs/sow/year (P/S/Y) production goal. Several units have already achieved this goal, and an elite few North American producers have surpassed the 30-pig mark.
The majority of sow units today fall into the range of 24 to 28 P/S/Y, so when we set a goal of 30, our focus is to push production to a range of 28 to 30 P/S/Y. Those who are mastering this level of production realize the importance of providing a clear understanding of the goal and the training necessary to meet or exceed 30 P/S/Y.
In this section of the Blueprint, we will concentrate on important management technologies that should be a part of the farrowing staff’s training program.
Understanding the Risk Factors
Sow herd health stability is one of the major risk factors that are obvious to most, but subtle differences can affect the quality of pigs at weaning (see “Creating Stable Herd Health,” National Hog Farmer, April 15, 2011, p. 5).
It is important to work with your veterinarian to develop a breeding herd vaccination protocol specifically for your farm. The first goal is to
establish a sow herd that does not have active infection by a major pathogen.
Subclinical infection by a pathogen in the sow herd might be expressed later in the life of the offspring, so controlling pathogen activity has two aspects:
- Controlling infections in the sow herd to support better reproductive performance.
- Providing quality pigs to the nursery or wean-to-finish facility to help ensure the population remains healthy and achieves growth parameters through the grow-finish stages.
Following are 10 herd-health-related risk factors that can affect reproductive efficiency:
- Replacement gilt health status prior to placement — Serological testing or oral fluid testing can help determine the porcine reproductive and respiratory syndrome (PRRS) status of replacement gilts. Some farms also test for Mycoplasma hyopneumoniae (MH) and swine influenza virus (SIV). Replacement gilts can be tested twice, several weeks apart (paired samples on each animal), to more accurately characterize their disease status. This type of profiling will reveal if the titer to a specific pathogen is rising, an indication of recent exposure, or if a titer is declining, which indicates the exposure occurred in the past.
An enzyme-linked immunosorbent assay (ELISA) test detects antibody level (i.e. titer), an indication that the animal was exposed. A polymerase chain reaction (PCR) test detects the genetic material of a pathogen, an indication that the pathogen is present in the sample. PCR and ELISA tests need to be performed prior to placement into the breeding barn.
- Stabilize the sow herd to major pathogens — Veterinarians have been using the term “stabilize” to mean that the sow herd is positive to a pathogen, such as the PRRS virus, but not shedding the virus to the offspring. If the replacement gilts become infected and are shedding the pathogen prior to placement in the sow herd, then the sow herd will develop active infection with resulting clinical signs developing.
Based on the status of your breeding herd, you may need to vaccinate gilts for PRRS, MH, porcine circovirus Type 2 (PCV2), SIV and ileitis, as well as any prebreeding vaccinations, such as parvovirus, leptospirosis and erysipelas (PLE).
Any time you add new animals to your breeding herd, you run the risk of making the sow herd unstable, which can reduce the ability of the management team to achieve the farm’s goals. An active infection in the sow herd can also create an unstable finishing population, so it is important to stabilize the breeding herd.
Manure or specific pathogen feedback is sometimes used to acclimate gilts and boost their immunity. However, it is important to consider what other pathogens might be in the feedback material.
- Stabilize replacement gilt
health — Development of replacement gilts starts with stabilizing them to the health challenges they will likely face, as well as developing their sexual
Most producers still use 300 lb. and 30 weeks of age as targets for when replacement gilts should be cycling and bred. The first step is to allow a minimum of six weeks for the gilts to acclimate through the use of proper vaccinations and exposure via cull animals or feedback material. Time is your ally, so longer periods are always better than shorter periods.
During the acclimation period, boar exposure is important for development of sexual maturity. Start boar exposure around 160 days of age. Rotating boars into the gilt pens on a daily basis is a common technique for gilt stimulation.
Equally important is to ensure one’s ability to determine when and if gilts have had an estrous cycle and to document the date the first standing behavior was observed. It is vital that gilts cycle at least once before being bred. Some farms target two estrous cycles on 25 to 35% of the replacement gilt population prior to placement into the breeding area.
- Sow body condition and parity structure — Proper sow body condition is a major risk factor to achieving outstanding performance. Maintaining good body condition throughout the year is equally as important as getting the sows back into proper condition after weaning. It is important for the breeding staff to understand seasonal and feed quality effects on body condition and to treat each animal as an individual.
Another aspect of the sow herd that impacts its ability to achieve outstanding reproductive performance is to maintain a parity structure that approaches 50-55% Parity 3 sows and older.
- Parturition is a risky time for sow and litter — The sheer size of a sow compared to the piglets is certainly a factor in preweaning mortalities, although it’s not the only one. While most preweaning mortalities occur within 2-3 days after birth, the risk remains throughout the nursing period.
Keep in mind that the sow is faced with extraordinary metabolic challenges as she produces large volumes of milk for her growing litter. The challenge is to maximize feed consumption during lactation.
- Prefarrowing plans — It’s a good idea to wash sows before moving them into farrowing crates. Some managers even rinse sows with a disinfectant after placement in a farrowing crate to minimize the pigs’ exposure to bacteria.
Make sure everything in the farrowing room is set up properly to provide the most ideal conditions for the sows and litters. Check waterers for proper flow, heat lamps/heat mats, feeders, air inlets/fans/cool cells, and farrowing crates to be sure that everything is in proper working order.
Piglets need to be taken care of as soon as they are born. Drying agents are commonly used on heat mats and in hot boxes. Some units towel-dry the piglets immediately after birth. This stimulates the piglets, but it also requires farrowing staff to be present throughout the farrowing process, including the evening hours.
Intense monitoring of the farrowing room is the key to achieving low stillborn rates (3.5-4.5%) and promotes excellent colostrum consumption by newborns. Farrowing attendants should make notes on sow cards to establish number born and time checks to establish each sow’s farrowing progress. This information is vital to determining when intervention is needed.
For example, if 20 minutes have elapsed since the last piglet was born, or if all of the piglets are dried off and nursing, then the sow might need to be manually checked or (“sleeved”).
Sleeving is not harmful as long as you use the proper technique. Wear an obstetrical sleeve and use plenty of lubricant. For added insurance and to promote good hygiene, lubricants containing a disinfectant can be used. Be very careful to not grab a bar on the farrowing crate or other contaminated areas with the sleeving hand that would contaminate the sleeve.
- Oxytocin has its place — Oxytocin can be a great tool to use during farrowing, when it is used correctly and not overdosed.
Recent research has shown that administering oxytocin early in the birthing process can create stillborn pigs. Oxytocin is useful when a significant amount of time has passed between piglets or the sow has not farrowed all of her piglets.
Observe the sow’s contractions to help determine if intervention is needed. Before oxytocin is administered, it is important to sleeve the sow to make sure a piglet is not stuck in the birth canal. You can help release a sow’s natural oxytocin by “tickling” the birth canal with a finger during the sleeving process. This might reduce the need to inject oxytocin. Newborn piglets that are towel-dried are allowed to nurse, which stimulates the sow naturally, before being placed in a hot box.
If the farrowing attendant determines oxytocin would be beneficial, inject 10 mg (0.5 cc) of oxytocin in the crease of the vulva (lateral to the vulvar opening) to help stimulate uterine contractions. Too much oxytocin can have a negative effect on uterine contractions, and can actually cause the uterine muscle to become fatigued and less efficient, therefore producing more stillborns.
A routine recommendation is to limit the use of oxytocin to two doses per sow for normal deliveries. Sows that are having obstetrical problems need to be treated individually.
- Colostrum management is vital — At birth, pigs have no circulating antibodies to protect them against major pathogens in their environment. Therefore, the sow must provide antibodies to her offspring through her colostrum. Besides avoiding chilling, the most critical aspect of early pig care is to ensure maximum colostrum consumption shortly after birth.
The protection provided in colostrum is called passive immunity. This immunity will wane, and each pathogen has a different decay time. Pig viability has a positive correlation with the degree of passive immunity that they acquire. Passive immunity helps protect pigs until their active immune system matures and can produce their own antibodies to major pathogens.
The time period that colostrum can be absorbed into the piglet’s blood system diminishes rapidly after birth, so the first suckle is important. Most colostrum is absorbed within six hours of the first suckle, although the piglets can absorb antibodies and white blood cells until gut closure, which occurs within 24 hours of the first suckle.
In the time span between six hours of life and eventual gut closure, it is estimated that a piglet’s ability to absorb molecules and cells is reduced by about 50%. It is vital that the farrowing house staff focus on all activities that help ensure adequate colostrum immediately after birth. Failure to provide adequate passive immunity results in relatively poor protection, leaving piglets more susceptible to early colonization by pathogens. Early colonization of bacteria means piglets will carry the organisms into the nursery where they will be shed, creating health challenges.
Complete maturity of the immune system most likely does not occur until 6 to 8 weeks of age, although for most concerns the piglet is capable of handling vaccines and exposure to pathogens prior to this age. Besides antibodies, colostrum contains lymphocytes (white blood cells), cytokines, nucleotides and various growth factors, which may affect the postnatal development of the piglets’ immune system.
- Cases for/against crossfostering — Some managers prefer to dry off each piglet and help it nurse. Others feel spending a short time in a hot box containing a drying agent is better for the piglets. The hot box is usually placed under a heat lamp beside the sow in the farrowing crate. It normally takes about 10 minutes for pigs to become dry and warm; they can then be placed near the sow’s udder for nursing. A common mistake is to leave the piglets in the hot box too long.
Another use of the hot box is as a modified split-suckling technique, intended to maximize colostrum consumption by all piglets. Piglets born first and that have nursed can be put in the hot boxes to allow late-farrowed piglets an opportunity to nurse.
Although the goal for the farrowing house staff should be to minimize crossfostering as much as possible, it is sometimes necessary to move piglets to another sow.
The importance of piglets consuming colostrum from their birth dam has been shown with MH, a major pathogen. The lymphocytes from the birth dam’s colostrum are more activated against MH and therefore are better at protecting the offspring. The take-home point is that the white blood cells are better utilized by piglets for passive protection when they nurse their birth dam.
A few farm trials conducted over the past five years have shown that in some circumstances, crossfostering can delay how quickly a pig will nurse. Early crossfostering has shown pigs nurse quicker, while older, crossfostered pigs can take up to 5-6 hours before they nurse the sow they were fostered onto.
Even with 24/7 farrowing attendants, the goal is to complete crossfostering within the first few hours of birth, but after adequate time for consumption of colostrum. The goal with crossfostering is to “even-up” litters or have the early crossfostering completed by the time the farrowing staff goes home on the day pigs are born.
Small piglets are accumulated shortly after birth and placed on a young parity female to reduce competition within the litter and produce better quality pigs at weaning. In some cases, more piglets are placed than a sow is expected to wean, so supplemental milk is provided to help the litter.
Crossfostering allows for the number of nursing pigs per sow to be maximized. Recent field trials have shown that challenging gilts to nurse as many viable piglets as they can handle in their first parity improves feed consumption during that first lactation and sets them up to perform even better in subsequent parities.
The common practice is to put 13-15 piglets on most gilts. Some gilts will not be able to nurse 15 pigs, so an attentive farrowing staff must watch for starve-out pigs, especially for 3-5 days after farrowing/crossfostering. Pigs that do not have a full abdomen or are constantly nudging the sow’s udder are not receiving adequate milk.
Not all sows will accept pigs from another litter. Generally, it is best to utilize young parity females for crossfostering or as nurse sows because they have smaller nipples and good-quality mammary glands.
There are many methods being used in North American production systems to provide adequate nutrition for every piglet. The best method is to allow piglets to nurse a sow, although an intense sow-to-farrowing crate ratio puts pressure on the system.
Historically, farrowing facilities were built to accommodate about seven breeding females per crate to maximize the use of more costly facilities. However, in recent years, intense farrowing practices are being relaxed through the use of supplemental milk decks or rescue decks (Figure 1). Some passionate and lively debates have defended both sides of this issue, but the important point is to provide every piglet with adequate nutrition.
An example of this intensity in farrowing is a program called “bump-weaning/bump-fostering,” where some sows are weaned earlier than normal to create a nurse sow for crossfostering purposes. When managed properly, sows are allowed to lactate a normal period of time, but the age of the piglets is younger than normal. The outcome is more uniform pigs at weaning but, eventually, the average weaning weights of the group are reduced. This reduction in weaning weights is caused by the delay in all piglets nursing the foster sow after placement and younger piglets at weaning.
When bump-weaning/bump-fostering was overused and weaning weight averages slipped, producers minimized the use of the practice and turned to raised decks with a supplemental milk replacer.
In U.S. production systems, there has been a gradual trend to reduce the number of breeding females per farrowing crate, which has created an opportunity to utilize more nurse sows vs. feeding artificial milk replacer.
- Managing crossfostered pigs — Use a permanent marker to identify piglets that have been crossfostered, whether they are good pigs or compromised pigs. It is not uncommon for a good pig to become a compromised pig. This happens when the transferred pig selects a mammary gland that has a limited ability to produce enough milk to meet its needs. This is particularly a problem for middle- and older-parity sows.
Late-term crossfostering may still be needed for pigs that otherwise would not be good-quality pigs at weaning. These older piglets are sometimes held on a nurse sow for an additional week to give them more time to reach proper weaning weights. The success of this activity depends on the health of the herd.
It is important to continue monitoring sows after the farrowing process is over. We recommend taking the sow’s temperature the day after farrowing. If the temperature is above 103° F., the use of an analgesic product such as Banamine-S can help control fever. Antibiotic therapies are usually farm specific and should be included if a fever is present post-farrowing.
Routine antibiotic therapies are not common in modern farrowing units, but if a sow was sleeved several times, an antibiotic injection may help control the possibility of a uterine infection.
The goal is to get the sow eating as soon as possible after farrowing. Adding water to their feed can help increase feed intake as well as water consumption, which is especially important in the hot summer months. Sows that are not eating and drinking will not be able to nurse piglets.
Feed is usually available at all times during postfarrowing, with an aggressive method of increasing the amount fed each day.
When an animal has been off feed for a couple of days, consider a B-complex injection. B vitamins are an important aspect of health and are produced by bacterial action in the lower bowel when normal consumption occurs.
Most farms process piglets at 1 to 3 days of age. Although some farms get along fine with a one-step processing procedure the day after birth, other farms have found that splitting up the processing activity provides labor efficacy and maximizes weaning weights.
Supplemental iron is needed to maximize growth in the piglet’s early life.
Some farms continue to clip pigs’ needle teeth, while other farms have abandoned the practice. Improper clipping can create infections in the gums of piglets, which sometimes creates an abscess. When teeth are not clipped, it is important to monitor facial lacerations of littermates closely. Facial lacerations generally will heal and may not cause major problems later in life, although increased outbreaks of Greasy Pig Disease caused by Staphylococcus hyicus is a management-related disease.
Docking of the piglets’ tails has become quite common in modern hog production systems. The use of long-acting antibiotics has optimized control of early colonizing bacteria and helped prevent umbilical abscesses and bacterial infections in piglets’ joints.
Piglet processing is usually completed by castrating the male piglets at 3-7 days of age. The testicle descends from the abdomen into the scrotum in all mammals. In male piglets, this activity occurs just prior to birth. Proper castration technique is important in reducing the incidence of scrotal hernias, which may be higher than normal if this process is influenced environmentally or genetically.
Much attention has been given to reducing the incidence of scrotal hernias. The age at castration will determine the best technique to use. One technique is to break the spermatic chord by pulling. Another is to extend the testicle far enough to allow the spermatic cord to be cut. Both techniques are effective, although cutting the spermatic cord is the preferred method to reduce post-castration problems in older pigs.
When a scrotal hernia occurs, the use of contracting tape can improve survivability. If you are having problems with castration, review your procedure with your veterinarian. He/she can help identify any managerial, environmental and health-related issues to ensure the farrowing staff understands the implications of their procedures.
Tackling Neonatal Diarrhea
One of the most aggravating aspects in swine production today is the presence of neonatal diarrhea. Farms that have an intense sanitation program and strive to maximize early pig care sometimes still struggle with neonatal diarrhea.
Diagnostic efforts to identify the pathogens involved often find enterotoxigenic (ETEC) E. coli; rotavirus group A, B or C; Clostridium perfringens type A; and Clostridium difficile at less than 7 days of age. An infection of coccidia is often associated with a diarrhea in pigs over 7 days of age.
The first step in correcting a neonatal diarrhea is to examine the sanitation program. Culturing samples obtained from cleaned and disinfected room surfaces can be eye-opening — even to the veterinarian. Even when a room has been properly sanitized, there is still a low level of bacteria residing in areas that the piglet will come in contact with. Often the bacteria and fungi are not pathogenic, but the culture helps illustrate that we are not sterilizing the environment that the piglet will experience in the first few hours of life.
Sanitation activities have been changed over the years to include detergent pre-wash products that fall into three general categories: neutral pH, acidic pH and alkaline pH. Detergents are soaps and therefore help reduce cleaning time and improve cleaning procedures.
Acidic pH detergents are more commonly used, although the biofilm that occurs on equipment is more easily attacked with some of the alkaline detergent products. Acidic detergents help brighten equipment by removing the mineral accumulation.
Hot water washing is less common in modern swine units due to the extra cost of heating the water. If hot water is available, it is still a good method of improving washing procedures.
Proper application of disinfectants needs to be monitored because the equipment ages and improper (reduced) amounts may be applied. Good sanitation must include the equipment that is used in piglet processing since it moves from room-to-room. Be sure to routinely clean and disinfect all hot boxes, weigh carts and processing equipment.
Stepping into the farrowing crate where pigs are scouring is another easy way to transfer pathogens from one litter to another. Don’t do it.
In some cases, improving the antibody levels in the sow through vaccination provides passive immunity to protect the piglet. E. coli vaccines are a great example.
Rotavirus vaccine has been added to several farms’ prefarrowing programs. Recently, rotavirus group C has created a greater challenge since the strain is not included in the commercial vaccine.
Clostridium perfringens type A is a ubiquitous bacterium that several years ago was found to be associated with neonatal diarrheas if beta toxin gene was present. It continues to be found in most early neonatal diarrhea, although the addition of Clostridium difficile complicates the situation and often creates a more severe diarrhea. Clostridium organisms alone are not necessarily bad. But the toxin they release creates conditions within the piglets’ intestines that cause the diarrhea.
In addition to proper sanitation and sow herd vaccination programs, it becomes necessary to develop a feedback program for sows to cover some farm-specific organisms. Feeding some type of material to sows in gestation, such as feces or piglet tissues, needs to be monitored closely to ensure it is properly administered far enough ahead of farrowing so that sows are not placed in crates while still shedding large amounts of pathogens.
Antibiotic therapies are the gold standard for treating a neonatal diarrhea. More recently, the use of , herbs and egg-derived antibodies are becoming more common.
In some cases, the neonatal diarrhea is not associated with increasing preweaning mortality, but more often affects weaning weights. This makes it more difficult to apply economic values to the problem, and it complicates the decision about which control method to use. Neonatal diarrheas are very complicated, but they should not be tolerated.
Weaning is one of the most stressful times for piglets and is especially stressful on their guts. Piglets are removed from their comfortable environment with an adequate supply of mother’s milk and placed into a new environment with new penmates, a new feed source, and a new delivery mechanism. Anything that can be done to minimize the amount of change and stress on piglets and their intestinal tract at weaning can help get them off to a better start.
One way to minimize this change is to make creep feed available in the farrowing crate. Not only can this help improve weaning weights, it will help get piglets used to the new source of feed they will encounter in the nursery. While creep feeding does add more cost per pig, most studies show that it is economically beneficial. Some are considering that piglets will “learn” to eat by associating with their dam’s eating activities, which may help pigs get started in the nursery.
P/S/Y is Multi-Faceted
Thirty pigs per sow per year is a very achievable goal, but many steps go into reaching this outstanding production level. Begin by making sure the farrowing staff is properly trained. Gilt development and acclimation, breeding herd stabilization, prefarrowing management, intense early pig care and postfarrowing management for sows are all crucial. And, don’t forget to consider how many of the pigs will be high-quality pigs at weaning, in order to maximize the number of full- value pigs moving through nursery and finishing facilities.