Swine production

22/02/2023

Camelpox is an extremely infectious skin disorder and the most common infectious viral illness of camels, occurring in most regions where camel farming is common. The camelpox virus (CMLV; genus Orthopoxvirus, family Poxviridae), the cause of this infectious disease, is closely related to the variola virus. The genes associated with viral replication activities and most of those important in additional host-related processes are identical in the two viruses
Symptoms of camelpox are fever, skin lesions, and lymph node inflammation. Pox lesions of different stages may form, most notably on the face, throat, and near the tail. The disease may be diagnosed based on clinical symptoms, although camel contagious ecthyma and camel papillomatosis induce similar symptoms . Multiple diagnostic methods are available, including transmission electron microscopy (TEM), the most rapid diagnostic tool for detecting the characteristic, brick-shaped orthopoxvirus in tissue samples or skin lesions . Immunohistochemistry can also be informative. PCR may be used to confirm the presence of viral nucleic acid, and DNA restriction enzyme testing can be used to identify specific strains of the CMLV
Prevention and control The infection, like smallpox in humans, may be controlled by separating diseased camels and injecting the remainder with the standard vaccinia virus vaccine or the recently developed CMLV vaccine, available live attenuated and inactivated. A booster vaccine dose is recommended for young camelids inoculated before 6–9 months. The inactivated vaccine can be injected yearly , and the live attenuated vaccine provides long-term protection.
A live attenuated candidate vaccine was produced in Sudan using a local strain of CMLV and assessed in a small-scale field study for safety and efficacy in experimental camels . Most tests revealed that the proposed vaccine is effective, safe, and can control the infection. Most vaccines are produced from the CMLV strains Ducapox 298/89, Jouf-78, VD47/25, and CMLV-T8. The attenuated Jouf-78 strain has been found to provide complete protection against CMLV (17). A new vaccine developed from serial multiplication of the KM-40 virus strain on the chorioallantoic membranes of 11-day-old embryonated chicken eggs has the potential to protect against camelpox in Old World camelids (Camelus dromedaries and Camelus bactrianus)
Treatment General non-specific treatment for infected camels is the administration of 10 mg/kg oxytetracycline and 0.2 mg/kg meloxicam for 5 days . A spray containing gamma benzene hexachloride, proflavine hemisulphate, cetrimide, eucalyptus oil, turpentine oil, and neem oil can also be used for wound therapy and fly control . Other ethnopharmacological applications are also widely used to treat camelpox . In humans, cidofovir would likely be beneficial in the treatment and short-term prevention of smallpox and kindred poxvirus infections, as well as the treatment of vaccinia sequelae in immunocompromised individuals Cidovir and its acyclic nucleoside phosphonate derivatives have shown promising therapeutic potency against camelpox

22/02/2023

Three Enterprises and Characteristics
Three types of swine production enterprises are farrow- to-finish, farrow-to-feeder, and feeder-to-finish. No single blueprint exists for these systems. Designing a production system that will complement your resources and lifestyle is the most important component to determining the best production system for you.

To determine which enterprise will work best in your situation, you must first consider the following:

Amount of capital, labor, and land available
Level of management and marketing skill needed
Social and environmental implications associated with manure management
Farrow-to-Finish
A farrow-to-finish enterprise involves breeding and farrowing sows, and feeding the offspring until they reach a market weight of about 280 pounds. The entire production period takes approximately 10 months, with 4 months for breeding and gestation and 6 months to raise the litter to market weight. Of the three systems, farrow-to-finish has the greatest long-run market potential and flexibility. This system also demands the most capital and labor, and requires a long-term commitment to the swine business. A small number of sows can fit into a crop operation nicely when farrowings are scheduled to avoid peak harvest times. With the current focus on animal welfare, most new farrow- to-finish operations are designed to hold gestating sows in pens rather than crates, which may increase the capital required for sow housing.

Farrow-to-Feeder
A farrow-to-feeder enterprise involves breeding and farrowing sows and then selling the piglets to finishing operations when they weigh 30 to 60 pounds. Compared to a farrow-to-finish operation, this option decreases the need for facilities, operating capital, and the amount of feed and manure handled. It also provides a good foundation for increasing the number of sows or expanding into a farrow-to-finish operation. The biggest drawback of this system is that producers, especially those with small herds, are at the mercy of a volatile feeder pig market. This may require farrowing sows in groups to increase the number of pigs available during periods of high demand.

Feeder-to-Finish
Most feeder-to-finish enterprises buy feeder pigs weighing 30 to 60 pounds and feed them to market weight. In many cases, existing facilities are adequate for this system. This system allows for minimum overhead, low labor requirements, and no long-term commitment. The feeder-to-finish operation offers an opportunity for a grain farmer to use homegrown feeds to finish pigs without having to manage breeding stock. The operation also may capitalize on the fertilizer value of the manure. Important points of concern are the source, health, and quality of purchased feeder pigs. Ideally, all feeder pigs should originate from a single farm to reduce potential herd health problems.

Feeding
Feed is the major expense of any swine production system. In general, a farrow-to-finish operation will spend 75 percent of its total expenses on feed, compared to 50 percent for farrow-to-feeder operations, and 65 percent for feeder- to-finish operations.

Example swine diets are presented in Table 1, but they will vary depending on your management program, feed quality, and the condition of the animals.
Growing your own grain, making bulk purchases of additional ingredients, and using your own grinder and mixer (or hiring the work done in some situations) are effective ways to lower feed costs. However, adequate storage for large quantities of feed ingredients is necessary.

One major consideration in planning a swine enterprise is how to get feed to the pigs. Ideally, animals in farrowing, gestation, and nursery units should be hand-fed and those in the growing-finishing units could get their feed from automatic augers.

10/08/2022

The SDSU swine herd consists of 150-sows managed in five groups with 30 sows/group. The production system is designed for batch farrowing every 4 weeks and weaning at 21 days of age.
Sow Teaching and Intensive Research Complex
The Sow Teaching and Intensive Research Complex serves as the hub of the teaching, research and Extension outreach activities for the SDSU swine program. A 50-seat modern classroom with education technology solutions also features portable pens at the front of the room, allowing pigs to be brought into the classroom to support teaching and discussion.
Viewing Windows and Raised Hallway
Observation windows and an elevated walkway enhance public outreach by allowing visitors to the facilities to view aspects of the modern production process—from boar collection and breeding to gestation and farrowing, without having to “shower in.” The viewing windows help fulfill SDSU’s mission of providing teaching, research and Extension opportunities to the general public, and to “demystify” pork production.

02/03/2022

24/11/2021

Sale of feeder pigs to finishing pig producers
Livestock auctions
Graded feeder pig sales
Slaughter hog sales to packer buying stations
Direct sales to major packing plants
Small packers/processors
Specialty sales direct to consumers
Feeder Pig Marketing
All of these marketing options are available to feeder pig producers. One of the most popular options is marketing directly to producers who finish pigs. This option has advantages for both parties. First, the buyer and seller know the price and delivery conditions in advance. Second, the direct-sale option reduces animal stress and disease risk. Third, the direct-to-finisher transaction voids commissions associated with a livestock auction.

Marketing feeder pigs through a livestock auction, graded sale, or buying station is another common option. Before using these markets, you should know the desirable weights and lot sizes that garner the highest price.

Slaughter Hog Marketing
Buying stations and direct sales to a major packer are popular options for marketing slaughter hogs. In both cases, producers are quoted a price before the sale is finalized.

Small packers and processors are an additional market available to slaughter hog producers. They often pay a good price, but their plant capacity and number of customers restrict the number of hogs they buy.

An auction barn is another option for selling slaughter hogs. Producers often use this market because of its location and convenience. The disadvantage of marketing through an auction barn is that producers are at the mercy of the supply and demand for hogs at the local market on that day. Prices may be well below or well above the national price on any given day and the producer must take the highest bid price. Auction barns also charge a commission regardless of the final bid price.

Specialty markets represent another alternative for slaughter hog producers. A popular form of direct sale enables the consumer to buy directly from a producer. The consumer then contracts with a small packer for customized meat cutting and packaging.

In summary, choosing a market involves doing your homework. When comparing market alternatives, you must account for differences in price received, transportation expenses, shrink losses, selling costs, and convenience. A market 50 miles farther from the farm that offers a higher price may in fact produce less net revenue than selling locally at a lower price when all marketing costs are included. You must know your alternatives and stay current with price trends and market preferences.

Three Enterprises and Characteristics
Three types of swine production enterprises are farrow- to-finish, farrow-to-feeder, and feeder-to-finish. No single blueprint exists for these systems. Designing a production system that will complement your resources and lifestyle is the most important component to determining the best production system for you.

To determine which enterprise will work best in your situation, you must first consider the following:

Amount of capital, labor, and land available
Level of management and marketing skill needed
Social and environmental implications associated with manure management
Farrow-to-Finish
A farrow-to-finish enterprise involves breeding and farrowing sows, and feeding the offspring until they reach a market weight of about 280 pounds. The entire production period takes approximately 10 months, with 4 months for breeding and gestation and 6 months to raise the litter to market weight. Of the three systems, farrow-to-finish has the greatest long-run market potential and flexibility. This system also demands the most capital and labor, and requires a long-term commitment to the swine business. A small number of sows can fit into a crop operation nicely when farrowings are scheduled to avoid peak harvest times. With the current focus on animal welfare, most new farrow- to-finish operations are designed to hold gestating sows in pens rather than crates, which may increase the capital required for sow housing.

Farrow-to-Feeder
A farrow-to-feeder enterprise involves breeding and farrowing sows and then selling the piglets to finishing operations when they weigh 30 to 60 pounds. Compared to a farrow-to-finish operation, this option decreases the need for facilities, operating capital, and the amount of feed and manure handled. It also provides a good foundation for increasing the number of sows or expanding into a farrow-to-finish operation. The biggest drawback of this system is that producers, especially those with small herds, are at the mercy of a volatile feeder pig market. This may require farrowing sows in groups to increase the number of pigs available during periods of high demand.

Feeder-to-Finish
Most feeder-to-finish enterprises buy feeder pigs weighing 30 to 60 pounds and feed them to market weight. In many cases, existing facilities are adequate for this system. This system allows for minimum overhead, low labor requirements, and no long-term commitment. The feeder-to-finish operation offers an opportunity for a grain farmer to use homegrown feeds to finish pigs without having to manage breeding stock. The operation also may capitalize on the fertilizer value of the manure. Important points of concern are the source, health, and quality of purchased feeder pigs. Ideally, all feeder pigs should originate from a single farm to reduce potential herd health problems.

Feeding
Feed is the major expense of any swine production system. In general, a farrow-to-finish operation will spend 75 percent of its total expenses on feed, compared to 50 percent for farrow-to-feeder operations, and 65 percent for feeder- to-finish operations.

Example swine diets are presented in Table 1, but they will vary depending on your management program, feed quality, and the condition of the animals. A summary of production inputs and manure output for different types of swine enterprise is listed in
Growing your own grain, making bulk purchases of additional ingredients, and using your own grinder and mixer (or hiring the work done in some situations) are effective ways to lower feed costs. However, adequate storage for large quantities of feed ingredients is necessary.
One major consideration in planning a swine enterprise is how to get feed to the pigs. Ideally, animals in farrowing, gestation, and nursery units should be hand-fed and those in the growing-finishing units could get their feed from automatic augers.

24/11/2021

24/11/2021

Dermatitis/Exudative Epidermitis /Eczema/Hyperkeratosis in Göttingen Minipigs
In the Göttingen minipig, a condition resembling exudative epidermitis of production swine is well known. In the Göttingen minipig the condition is sometimes called eczema or hyperkeratosis of the Göttingen minipig to differentiate it from the exudative epidermitis caused by Staphylococcus hyicus. It is recommended that the name hyperkeratosis should not be used unless a histological diagnosis of hyperkeratosis has been confirmed.

The condition is most often seen in younger minipigs (3–4 months or younger); however, is sometimes encountered in older minipigs as well. Black scabs usually develop on the head first, and may or may not progress to become more generalized.

Exudative epidermitis in the production pigs is caused by toxin-producing Staphylococcus hyicus, but it has not been possible to associate the condition seen in Göttingen minipigs with any primary infectious agent to date. Furthermore, the general health of the minipigs is rarely affected, whereas piglets with exudative epidermitis caused by S. hyicus often show signs of clinical disease. Candida albicans may sometimes be isolated from the lesions, but it is a part of the normal cutaneous flora of the Göttingen minipig and is not always isolated in these cases. Therefore, Candida is not considered to be the cause of the condition. However, in some cases the involvement of Candida may cause the clinical condition to become more severe.

In the minipig, the condition is normally self-limiting and the lesions often heal more or less completely within a couple of months. The skin in the affected areas may be slightly redder after recovery relative to the normal skin color. Minipigs with a history of dermatitis and a difference in skin color due to the condition typically should be excluded from dermal toxicity and wound-healing studies.

24/11/2021

Advantages of deep bedded cold barn systems
The primary economic advantages of tarp-covered cold barns for swine production result from low capital investment and fixed costs and from some reduction in certain operational costs. Of all the fixed costs of swine production, those for construction and maintenance of the buildings stand out as the most significant.

Hoop barns are relatively cheaper and simpler to erect and can be easily constructed by the farmer (Onan et al., 2016; Hutu, 2005). For example, gestation units (without the specific gestation equipment) cost around 15,000 euro. Addition of feeding stalls raises the price to about 25,000 euro, but use of feeding stalls cuts total feed usage by 4.5% and allows for more effective control of sow body condition by allowing tailored feeding of each animal (Brewer et al., 1999).

Grow/finish units cost from 10,000 to 17,000 euro or about 50–85 euro per animal space, which is ¼ to ½ the cost of a conventional unit (Brumm et al., 1997; Kruger, 2006).

Some of the variable costs of operating a hoop housing system are also lower than conventional. These include reduced expenditure for electricity for lighting and ventilation, reduced fuel expense for heating, and lower property taxes and insurance fees. There is also the advantage of using home-grown grains and bedding materials for the system.

24/11/2021

Probiotics also protect piglets by generating antimicrobial compounds or by upregulating immunity against pathogenic infection (Broeckx, Vandenheuvel, Claes, Lebeer, & Kiekens, 2016; Chen, Woodward, Zijlstra, & Gänzle, 2014; De Angelis et al., 2007; du Toit et al., 1998; Lin et al., 2007; Martín et al., 2009; Ritter et al., 2018). The production of organic acids, exopolysaccharides and other antimicrobial compounds is independent from the lifestyle of probiotics and was shown to contribute to pathogen inhibition in weanling pigs (Chen, Levy, & Gänzle, 2016; Martino et al., 2016; Yang, Galle, et al., 2015). Compared to host-adapted probiotics, nomadic or environmental probiotics are more likely to clear pathogens by stimulating immune defenses (Scharek-Tedin et al., 2013; Sonia et al., 2014; Upadhaya et al., 2017; Wang, Haifeng, et al., 2009). Accordingly, in vitro identification of immunomodulatory traits of a strain has been widely used to predict its potential use as probiotic, which also has raised a concern about the validity of these in vitro studies. Most of positive results detected in IPEC-J2 cell based evaluation were not validated in animal studies, or the results from animal studies were not as significant as predicted by cell line test using the same strain (Holzapfel et al., 2018; Macha et al., 2004; Marciňáková, Klingberg, Lauková, & Budde, 2010; Suo et al., 2012; Wang, Ji, et al., 2018; Wang, Zheng, et al., 2018; Wu et al., 2016; Zhao & Kim, 2015). In terms of inhibiting pathogen infections without colonization, both host-adapted and non-host-adapted probiotics can provide effective protections either through sow milk or directly feeding suckling and weanling pigs (Bohmer et al., 2006; Li et al., 2012; Scharek et al., 2005; Scharek-Tedin et al., 2013; Sonia et al., 2014; Tan et al., 2018; Upadhaya et al., 2017; Wang, Haifeng, et al., 2009; Zhou et al., 2015). But the precondition is selecting probiotics with high competitiveness in swine gut or efficient immunomodulation validated by in vivo studies and maintaining relevant cell counts in the intestine by continuous feeding (Kreuzer, Janczyk, et al., 2012; Szabó et al., 2009).

Grower/finisher pigs receive more protection from a mature immune system, which shifts the aim of applying probiotics toward improving growth performance (Chen et al., 2006b; Dowarah et al., 2017; Suo et al., 2012). Grower/finisher pigs also require higher doses of probiotic strains, thus, cost associated with preparation and stability of probiotic become more important. Preserving probiotics in a dry form is required for quick mixing with feed and to maintain a long shelf life (Broeckx et al., 2016). Spore forming probiotics can be added prior to pelleting of feed, which occurs at temperatures that are lethal to vegetative bacterial cells. Potent enzymatic activity is also a favorable trait of probiotics to aid feed digestion and enhancing growth performance of grower pigs (Ritter et al., 2018). Spore-forming Bacillus spp. have been referred to as suitable commercial probiotics for growing pigs due to the excellent viability during drying or pelleting, extended shelf life and potent phytase and cellulolytic activity (Larsen et al., 2014; Ritter et al., 2018). Feed fermentation with lactic acid bacteria (Jørgensen, Sholly, Pedersen, Canibe, & Knudsen, 2010; Lee, Gilliland, & Carter, 2001) is an alternative strategy to include probiotics while avoiding concerns related to drying and dry survival. Host-adapted lactobacilli are highly competitive in cereal fermentations; existing technology thus allows feed fermentations at a large scale (Gänzle & Zheng, 2018). Feed fermentation with probiotic lactobacilli improves the growth performance of pigs by combining the probiotic effects of lactic acid bacteria with the nutritional benefits of feed fermentation (Marko et al., 2014; Missotten, Michiels, Ovyn, de Smet, & Dierick, 2010; Nkhata, Ayua, Kamau, & Shingiro, 2018). Note also that a longer period of probiotics supplying for grower/finisher pigs were suggested to achieve more improvemets in growth peformance (Chen et al., 2006b; Dowarah et al., 2017; Suo et al., 2012; Wang, Cho, et al., 2009).

In conclusion, effective probiotics are a promising solution to address the increasing concern of antibiotic resistance as a result of using antimicrobial growth promotors. The results of probiotic intervention trials in swine, however, are often inconsistent, which clearly demonstrates that “one size does not fit all” and specific probiotic strains should be selected for specific applications. The critical review of selection criteria and particularly the consideration of the ecological origin of probiotics may guide future applications to use probiotics as an effective tool in swine production.

24/11/2021

Selection criteria for probiotic application
To achieve the diverse purposes of applying probiotics in swine production, different beneficial profiles are required for probiotic strains. An overview on the relevance of different selection criteria at different stages of life is provided in Fig. 2. Only pig-adapted strains that are administrated in early life or shortly after antibiotic treatment are likely to colonize the intestine of piglets (Duar, Frese, et al., 2017; Duar, Lin, et al., 2017; Martínez et al., 2018; Morelli, 2000; Walter et al., 2018; Zheng, Zhao, Lin, & Gänzle, 2016). Host adapted lactobacilli are tolerant to acid and bile salt (De Angelis et al., 2007), and possess the metabolic characteristics (Ritter et al., 2018) to compete for adhesion sites and nutrients in swine gut (Duar, Lin, et al., 2017; Zheng et al., 2016). Altering the type of early intestinal colonizers in mice showed a lasting influence on the development of microbiome (Martínez et al., 2018), indicating the possibility to shape the development of gut microbiota of neonates by introducing host-adapted probiotics early in life. In addition, higher competitiveness of these strains to outcompete pathogens is of importance for piglets who cannot receive full protection from their immature immune system. Thus, to educate the development of gut microbiota or to competitively exclude pathogens, it is necessary to select pig-adapted probiotics. Both phylogenetic inferences and associated functional studies should be combined to elucidate host-adaption of certain strains or species, rather than simply depending on the source of isolation (Duar, Lin, et al., 2017; Zheng et al., 2016). To date, studies on host-adaption have been limited to Lactobacillus; a systematic investigation of host adaptation in other species used as probiotic remains subject to future investigation.

24/11/2021

Gestation
The sow's role in swine production is either being pregnant or nursing a litter. Wean to estrus interval is therefore expected to be shorter. Increasing feed by 50%–100% (flushing) or feeding high energy sources such as dextrose for 10–14 d before first service, increases ovulation rate and litter size.8 Feed fed is usually decreased after mating to an appropriate gestation diet because sows that are overfed throughout gestation have high embryonic mortality, produce small litters, farrowing complications, crush piglets, reduce feed intake during subsequent lactation and are less prolific at the next parity.103 Increased level of dietary energy intake to gilts and sows after mating is reported to reduce systemic progesterone concentrations leading to increased embryo mortality in early pregnancy. However, this observation is not unanimously agreed on in the scientific literature.104 It was reported that sows with back fat depths of 23 mm or more at farrowing have depressed appetite during lactation.103

Pregnant sows are restrictively fed to control body weight and prevent excess weight gain. Hence, energy is the limiting factor for gestating sows and feed allowance necessary to provide energy requirements must be considered first when formulating diets for pregnant sow. Nutrient requirements of sows change significantly with advancement of pregnancy. This factor calls for segregated phase feeding. A 3-phase feeding program is practiced by farmers to meet nutritional needs of sow and to prevent over feeding of nutrients which increase cost and eventually negatively affect the environment through nutrient excretion.105,106 These phases are: 1) early gestation (d 0–30), embryo survival and implantation are impacted, 2) mid-gestation (d 30–75), body growth in young sows and recovery of body reserves lost during lactation in older sows are impacted and 3) late gestation (approximately the last 45 d), during which fetal and mammary growth are impacted.8 Fetal weight, fetal protein content and mammary protein content increase 5, 18, and 27 times, respectively, in the last 45 d of gestation.8 Conceptus protein content has greater priority for nutrient supply than maternal weight gain and increases rapidly after d 68 of gestation. Therefore, amino acid and energy requirements are greater in late gestation than in early gestation even though amino acid requirements increase to a higher degree than energy requirements in late gestation. Generally, sow's feed intake during gestation should be based on objective measure of body weight and back fat depth.107 Feed intake during the last 14–21 days should be regulated to avoid a negative energy balance prior to farrowing, with the goal of higher feed intake in early lactation, easier farrowing and adequate birth weights of newborn pigs.103 However, beneficial effect of feed restriction prior to parturition is reduction of postpartum dysgalactia syndrome (PDS). The PDS in sows is characterized by inadequate and insufficient colostrum and milk production during the first days post-natal which was previously termed mastitis, metritis and agalactiae, or MMA, syndrome.108 Also keeping the feed low in energy and high in fiber through parturition and into the first few days of lactation may improve intestinal function and initiation of lactation.109

24/11/2021

When considering how swine production will be affected by climate, perhaps the best place to start is to consider the present day vulnerabilities of the industry. The swine industry, like most of the meat production industry, is based on intensive production with trends suggesting future increases in intensification. This industry model depends on cheap grain, cheap energy, and manageable disease control. Some expect that future temperature, and precipitation frequency and intensity may have direct impacts on nonintensive swine production but are not likely to directly affect intensive production because the barn environment is controlled. However, there could be an increase in the frequency, intensity, and severity of both severe storms (e.g., hurricanes, tornadoes, etc.), which might increase the upset of large open-air lagoon treatment systems and flooding of barns. This could lead to increased pressure on intensive operations to modify current manure treatment systems. Climate effects could, thus, have negative impacts on feed grain production, which will affect its availability and price. Climate influences would also have indirect impacts on energy costs as demands for renewable energy increase, which could also put upward pressure on feed grain prices as bioenergy production competes for feed grains. The climate impacts on growth, reproductive success, and distribution of diseases may impact the ability to manage disease. This concern may be heightened in intensive production relative to nonintensive systems owing to the density of animals. Future greenhouse gas mitigation efforts may produce costs or revenue opportunities for the swine industry. Last, the role of reactive nitrogen (Nr) in climate and other intertwined issues could be very important. Swine producers will need to adapt to all these changes to maintain production levels.

24/11/2021

Maternal Behavior in Swine
In modern swine production systems, sows are often kept in crates which limit maternal behaviors due to space confinements. However, when straw and branches are provided to provide a semi-natural environment, sows readily engage in nest building behavior prior to parturition (1–7 h) and this can increase time spent in lateral recumbency during the process (Damm et al., 2000). Both farrowing and nest building behaviors appear to be associated with stress reaction patterns, especially in gilts. Gilts that reacted calmly to stress exhibited better nest building and farrowing behaviors than did more behaviorally active individuals (Thodberg et al., 2002).

Further, personality traits, as reflected by fear and anxiety expressed in the presence of humans, have been linked with maternal ability. Higher levels of fear and anxiety were associated with a longer duration of farrowing and more stillborns (Janczak et al., 2003) whereas sows that were more responsive to piglet demands and not afraid of people had better piglet survival (Grandinson et al., 2003). Losses could possibly be reduced by genetically selecting for the maternal component of farrowing survival which would reduce stillbirths while not negatively affecting total piglets born (Leenhouwers et al., 2003). Further, genetic selection targeting piglet survival by reducing crushing of piglets could be considered in breeding programs (Baxter et al., 2011). The pre-lying behavior of sows tends to be crucial for piglet survival. Sows that perform “sniffing”, “looking around”, and “nosing” before lying down tend to be less likely to crush piglets than sows that don’t perform these behaviors (Wischner et al., 2010). Additionally, sows that did not crush piglets were more restless pre-partum and engaged more frequently in nest building than more relaxed sows. There may be differences between the best genetic selection program for intensively housed sows and extensively raised pastured sows.

Poor maternal behaviors, such as savaging and eating piglets, have been linked to certain (QTL) quantitative trait loci (Chen et al., 2009). Vangen et al. (2005) reported that possible behaviors that could be influenced by genetic selection are a sow’s reaction to people, including fear and aggression, especially when her piglets are handled. Selection of sows for calm behavior during farrowing may help make intensively raised sows more productive (Snieder et al., 2011). In addition, behavior of gilts assessed at five months of age associated with subsequent economically important traits such as piglets born alive and wean to estrus interval (Snieder et al., 2011).

Olfactorial, thermal, and tactile cues are used by piglets to locate the teats (Rohde Parfet et al., 1990). Newborn pigs engage in teat seeking very rapidly after birth, with an established and relatively consistent teat order being evident after about 4 days (de Passillé et al., 1988). Although larger, faster-growing piglets tend to suckle the more anterior teats, exceptions regularly occur (Winfield et al., 1974), with less stable teat orders being more evident in larger litters than in smaller ones. However, survival of piglets appears to be s*x biased. Even though maternal investment in male piglets is higher, male-mortalities exceed female ones (Baxter et al., 2012). It is speculated that piglet survival represents a combination of the maternal genetic component (genotype of the sow) and the direct genetic component (genotype of the piglet) (Leenhouwers et al., 2001). In contrast to other species, sows are tolerant of foreign young, particularly in the first few days postpartum, and fostering can be achieved relatively easily at this time (Signoret et al., 1975).