Troubled Process of Parturition of the Domestic Pig

Over the past three decades, efficient breeding and management have almost doubled the litter size of sows. Simultaneously, duration of farrowing has increased markedly. The expulsion phase of parturition in the hyper prolific sow is now 3 to 5 times longer than it was in the early 1990s. There has also been a constant downward trend in piglet birth weight, along with a similar trend in colostrum intake, which is an important risk factor for piglet mortality. Together with these trends, an increase in farrowing complications, such as postpartum dysgalactia and retention of placenta, has been reported. This paper investigates group housing of sows during gestation, farrowing and lactation, focusing on management strategies of the sow. In short, the sow needs to be given space and enrichment materials for adequate expression of nest-building behavior. Maternal characteristics may be utilized to improve the success rate of reproductive management during farrowing and early lactation. The lower piglet birth weight and compromised immunity of newborn piglets warrant investigation in the search for novel management tools. Robust breeds with somewhat lower litter size, but improved resilience and increased birth weight may be needed in the near future.Peer reviewe

Influence of Sow Gut Microbiota on Colostrum and Piglet Performance

Colostrum being the sole source of immunoglobulin and energy plays an essential role for piglet survival and growth. Studies have shown that colostrum and milk intake also influence the gut development and maturation of piglets. The early life colonization and development of the gut microbiota primes the development of the adult microbiome and has long-term impact on the health of the pigs. Growing number of evidences suggest that certain microbial species can exert beneficial effect on the sow and piglets, and thus improve production performances like colostrum yield, colostrum quality, sow physiology around farrowing, piglet weight gain, and health during lactation and weaning. The gut microbiota of pig which is unique at suckling stage, largely acquired from the mother, shifts over time. Multiple factors like age, environment, production system, diet can influence the gut microbiota of sow and piglets. The improvement of the sow and piglets microbiota toward beneficial bacteria can also be done by probiotic, prebiotic, and different feed additive applications.Peer reviewe

Successful farrowing in sows

Years of genetic selection of breeding sows have considerably increased the number of piglets born in each litter of this multiparous species. This economically driven result has not always preceded the structural development of an environment that accommodates sows’ physiological need for farrowing. Farrowing is a complex event driven by several hormones that interact with each other to induce the onset of parturition. These hormones are responsible not only for the induction of parturition, but also for triggering visible behavioural changes. Activities such as rooting, pawing, turning and walking increase considerably 24h prior to farrowing and characterise what is known as nest-building behaviour. This behaviour very closely correlates with the environment of the sow before farrowing begins, and is stimulated by the presence of nest-building material such as roughage or straw. Modern housing systems have promoted the confinement of the farrowing sow to crates, which greatly limit the sow’s movements and often preclude bedding or any other nest-building substrate. Perinatal mortality between countries and between herds varies considerably, but remains an important reason for the loss of piglets in their very first days of life. Excessively prolonged farrowing increases the number of stillborn or weak piglets. The aim of this study was to determine which factors contribute to successful farrowing, thus reducing perinatal mortality and improving the welfare of sows and piglets at parturition. We aimed to test different movement sensors to measure changes in the farrowing-related activity of sows to facilitate the prediction of parturition in sows. We also sought to determine how the intensive housing of sows in crates affects the duration of farrowing, to identify some of the sow’s hormonal parameters (cortisol, progesterone and oxytocin), to measure piglet mortality and growth, and identify which sow-related or environment-related factors affect the duration of farrowing. We also aimed to determine whether increasing the amount of crude fibre in the diet fed to sows in late pregnancy and early lactation would affect piglet growth and the body condition of the sow as well as reduce constipation. The average general activity of the sows, monitored with movement sensors, was higher in the 24-h interval prior to farrowing than in all the other 24-h intervals monitored (p less than 0.05). The duration of farrowing was on average 89 to 93 min longer in the sows housed in a farrowing crate than in the sows housed in a farrowing pen (p less than 0.05). The average concentration of the post-expulsion oxytocin pulses (measured within 6 min after expulsion of the piglets) for the sows housed in farrowing crates tended to be lower (38.1 ± 24.6 pg/ml; n = 9) than for the sows housed in pens (77.6 ± 47.6 pg/ml; n = 9; p = 0.08). The duration of farrowing strongly associated with the oxytocin values (p less than 0.001). Sows with a duration of farrowing longer than 300 min had 1.3 ± 1.3 (mean ± SD) stillborn piglets in study I, and 1.5 ± 1.8 stillborn piglets in study IV, whereas sows with a duration of farrowing shorter than 300 min had 0.6 ± 1.0 stillborn piglets in study I, and 0.4 ± 0.8 stillborn piglets in study IV (p less than 0.001). Higher back-fat values (p less than 0.001) and lower constipation index scores (p less than 0.01) indicative of constipation, negatively affected the duration of farrowing. The sows fed with a 7% crude fibre diet (FIBRE) had an average constipation score of 2.1 ± 1.3 (mean ± SD), whereas the sows fed with a 3% crude fibre diet (LACT) had an average score of 1.2 ± 1.1 (p less than 0.001). Moreover, 22% of the sows in the LACT group exhibited extremely severe constipation (more than five consecutive days without producing faeces), whereas only 5% of the sows in the FIBRE group showed this condition (p less than 0.05). In conclusion, sows housed in crates exhibited a longer duration of farrowing, a lower concentration of oxytocin during parturition and a higher number of stillborn than did sows housed in pens. Allowing the sow to move freely immediately before and during farrowing, thereby reducing constipation and avoiding excessive fattening of the sow during late gestation, all seemed to be key factors in shortening farrowing time, and thus reducing perinatal mortality. Photocells and force sensors reliably measured the activity of crated sows, thus enabling the development of an automated system for predicting the onset of parturition. Increasing the amount of crude fibre in the diet during late pregnancy and early lactation promoted intestinal function and water intake, thereby drastically reducing the risk for prolonged and severe constipation while having no substantial negative effect on the energy balance-related parameters of the sow.Vuosia jatkunut jalostusemakoiden valinta on tuntuvasti kasvattanut pahnuekokoa. Pahnuekoon kasvun taustalla on ollut pyrkimys tuotannon taloudelliseen tehokkuuteen. Pahnuekoon kasvusta johtuvia muutoksia emakoiden fysiologisissa tarpeissa ennen synnytystä, synnytyksen aikana ja sen jälkeen ei välttämättä ole pystytty ottamaan huomioon tuotantoympäristön suunnittelussa. Porsiminen on monisyinen tapahtuma, jota ohjailee monien toinen toisiinsa vaikuttavat hormonit, jotka aikaansaavat synnytyksen käynnistymisen. Nämä hormonit eivät ainoastaan käynnistä synnytystä, vaan vaikuttavat myös merkittäviin muutoksiin emakon käyttäytymisessä synnytyksen lähestyessä ja sen aikana. Emakon synnytykseen liittyvä aktiivisuus, kuten tonkiminen, kuopiminen, kääntyminen ja kävely lisääntyvät merkittävästi noin 24 tuntia ennen synnytyksen alkua ja ovat tärkeä osa pesäntekokäyttäytymistä. Tämä synnytykseen liittyvä käyttäytyminen on riippuvainen ympäristöstä ja sen ilmeneminen edellyttää, että tonkimismateriaalia kuten karkeaa rehua ja olkea on saatavilla. Nykyaikainen sikatalous on edistänyt emakoiden pitoa porsituskarsinoissa, joissa yleensä on kääntymisen estävät porsitushäkit, jotka suuresti rajoittavat emakon liikkumista ja estävät korsirehun ja pesäntekomateriaalin käytön. Porsaiden kuolleisuus vaihtelee eri maissa merkittävästi, mutta se on yleensä tärkeä syy porsaiden menetyksille ensimmäisten elinpäivien aikana. Pitkittyneen synnytyksen tiedetään lisäävän kuolleena tai heikkoina syntyvien porsaiden osuutta pahnueessa. Tämän tutkimuksen tavoitteena oli määritellä onnistuneeseen porsimiseen vaikuttavia tekijöitä, jotka vähentävät porsaskuolleisuutta ja parantavat emakoiden ja porsaiden hyvinvointia synnytyksen yhteydessä. Tarkoituksenamme oli testata liikettä mittaavien tunnistimien käyttöä porsimiskäyttäytymisen ja emakon aktiivisuuden mittareina. Tavoitteenamme oli myös tutkia porsituskarsinamallin vaikutusta synnytyksen kestoon ja synnytyksen kestoa sääteleviin hormonaalisiin tekijöihin (kortisoni, progesteroni ja oksitosiini), porsaiden kasvuun ja kuolleisuuteen ja selvittää mitkä porsimisympäristöön ja emakkoon liittyvät tekijät vaikuttaisivat synnytyksen kestoon. Edelleen tavoitteenamme oli tutkia lopputiineyden ja imetyksen aikaisen rehun kuitupitoisuuden vaikutusta porsaiden kasvuun, emakon kuntoluokkaan ja ummetuksen esiintymiseen. Emakon yleinen aktiivisuus liikettä mittaavien tunnistimien avulla mitattuna oli selvästi kasvanut viimeisen 24 tunnin aikana ennen porsimista verrattuna muihin 24 tunnin jaksoihin ennen ja jälkeen porsimisen (p < 0.05). Porsimisen kesto oli keskimäärin 89-93 minuuttia pidempi emakoille, jotka porsivat kääntymisen estävässä porsimishäkissä verrattuna emakoihin jotka porsivat vapaasti porsimiskarsinassa (p < 0.05). Keskimääräinen porsaiden syntymän jälkeinen oksitosiinipulssien konsentraatio näytti olevan matalampi emakoille jotka porsivat kääntymisen estävässä porsimishäkissä (38.1 ± 24.6 pg/ml; n = 9) verrattuna emakoihin jotka porsivat vapaasti karsinassa (77.6 ± 47.6 pg/ml; n = 9; p = 0.08). Porsimisen kesto korreloi vahvasti emakoilla mitattuihin seerumin oksitosiini – pitoisuuksiin (p < 0.001). Emakot joilla oli pidempi kuin 300 minuuttia kestävä synnytys oli 1.3 ± 1.3 (ka ± KH) kuollutta porsasta osatutkimuksessa I, ja 1.5 ± 1.8 kuollutta porsasta osatutkimuksessa IV, kun taas emakoilla joilla oli lyhempi kuin 300 minuuttia kestänyt synnytys oli 0.6 ± 1.0 kuollutta porsasta osatutkimuksessa I, ja 0.4 ± 0.8 kuollutta porsasta osatutkimuksessa IV (p < 0.001). Korkeammat selkäsilavan arvot (p < 0.001) ja alhaisemmat ummetusindeksit (p < 0.01) viitaten ummetukseen vaikuttivat negatiivisesti synnytyksen kestoon. Emakoilla joilla oli 7% kuitua rehussa (FIBRE) oli keskimäärin 2.1 ± 1.3 (ka ± KH) ummetusindeksi, kun sitävastoin emakoilla joilla oli 3% rehun kuitupitoisuus (LACT) oli keskimäärin 1.2 ± 1.1 ummetusindeksi (p < 0.001). Lisäksi yli 22% emakoista LACT ryhmässä kärsi erittäin voimakkaasta ummetuksesta, joka kesti yli 5 vrk. Ainoastaan 5% FIBRE ryhmän emakoista kärsi voimakkaasta ummetuksesta (p < 0.05). Yhteenvetona emakot, jotka porsivat kääntymisen estävässä porsitushäkissä, synnyttivät pidempään ja niillä mitattiin alhaisempia oksitosiinitasoja ja enemmän porsaiden syntymäkuolleisuutta kuin emakoilla jotka porsivat vapaasti porsituskarsinassa. Emakon pitäminen vapaassa porsituskarsinassa ennen synnytystä ja synnytyksen aikana, alentaen synnytyksen yhteydessä esiintyvää ummetusta ja ylilihavuuden välttäminen tiineyden loppuvaiheessa kaikki näyttävät olevan avainasemassa lyhentäen synnytyksen kestoa, vähentäen porsaskuolleisuutta ja parantaen synnytyksen onnistumista. Fotosolut ja liiketunnistimet mittaavat luotettavasti emakon aktiivisuutta porsituskarsinassa, ja tätä teknologiaa voidaan jatkossa hyödyntää synnytyksen ennustamiseen. Rehun kuitupitoisuuden lisääminen ennen porsimista ja varhaisen laktaation aikana paransi suolen toimintaa ja veden kulutusta vähentäen merkittävästi ylipitkän synnytyksen riskiä ilman negatiivisia vaikutuksia emakon energiatasetta kuvaaviin laktaation aikaisiin aineenvaihdunnallisiin muuttujiin

Herd-level risk factors for chronic pleurisy in finishing pigs : a case-control study

Background Chronic pleurisy is a common finding in slaughtered pigs in post-mortem meat inspection. The prevalence of pleurisy has been increasing during the last decade also in Finland. The aim of this prospective case-control study was to search for environmental, infectious and management-related herd-level risk factors for pleurisy in the slaughterhouse. Altogether 46 Finnish pig herds, including 25 control (low pleurisy prevalence in meat inspection) and 21 case (high pleurisy) herds, were enrolled in the study and visited during the tenth week of the rearing period of finishing pigs. Herd personnel were asked about basic herd information, management and environmental factors. Selected pigs were examined clinically, environmental parameters were measured and 15 blood samples per herd were taken during herd visits. Antibodies againstActinobacillus pleuropneumoniaserotype 2 (APP2) and ApxIV toxin and swine influenza virus were measured. After the slaughter of study pigs, meat inspection results of the batch were gathered from slaughterhouses. Multivariate logistic regression model was built to identify possible risk factors for a herd to be a case herd (i.e. having high pleurisy values). Results Finishing herd type and herd size were observed to act as risk factors. None of clinical signs of pigs, management-related factors or environmental measurements were associated with herd status. Conclusions As previously known, in endemic and subclinical infections such as APP, herd factors are important, but detailed risk factors seem to be difficult to identify.Peer reviewe

Developments of reproductive management and biotechnology in the pig

This review aims to describe changes in production environment, management tools and technology to alleviate problems seen with the present hyperprolific sow model. Successful parturition in the pig includes the possibility to express adequate maternal behaviour, rapid expulsion of piglets, complete expulsion of placenta, elimination of uterine contamination and debris, neonatal activity and colostrum intake. We focus on management of large litters, including maternal behaviour, ease of parturition, colostrum production, piglet quality parameters and intermittent suckling. There are also some interesting developments in technology to assess colostrum and immune state of the piglet. These developments may be utilized to improve the success rate of reproductive management around farrowing, lactation and after weaning. We also discuss new insights in how to examine the health of the mammary gland, uterus and ovaries of hyperprolific sows. Finally, we assess the latest developments on breeding and technology of hyperprolific sows, including artificial insemination (AI), real-time ultrasound of the genital tract and embryo transfer (ET). We conclude that 1) for the sow to produce sufficient colostrum, both the behavioural and physiological needs of the sow need to be met before and after parturition. Furthermore, 2) new ultrasound and biopsy technology can be effectively applied for accurate diagnosis of inflammatory processes of the udder and uterus and timing of AI regarding ovulation to improve insemination efficiency. Finally, 3) developments in cryopreservation of germ cells and embryos appear promising but lack of valid oocyte collection techniques and nonsurgical ET techniques are a bottleneck to commercial ET. These latest developments in management of parturition and reproductive technology are necessary to cope with the increasing challenges associated with very large litter sizes.Peer reviewe

Management of reproduction: piglet survival and fertility of the sow

As a result of intensive breeding, litter size has considerably increased in pig production over the last three decades. This has resulted in an increase in farrowing complications. Prolonged farrowing will shorten the window for suckling colostrum and reduce the chances for high-quality colostrum intake. Studies also agree that increasing litter sizes concomitantly resulted in decreased piglet birth weight and increased within-litter birth weight variations. Birth weight, however, is one of the critical factors affecting the prognosis of colostrum intake, and piglet growth, welfare, and survival. Litters of uneven birth weight distribution will suffer and lead to increased piglet mortality before weaning. The proper management is key to handle the situation. Feeding strategies before farrowing, management routines during parturition (e.g. drying and moving piglets to the udder and cross-fostering) and feeding an energy source to piglets after birth may be beneficial management tools with large litters. Insulin-like growth factor 1 (IGF-1) -driven recovery from energy losses during lactation appears critical for supporting follicle development, the viability of oocytes and embryos, and, eventually, litter uniformity. This paper explores certain management routines for neonatal piglets that can lead to the optimization of their colostrum intake and thereby their survival in large litters. In addition, this paper reviews the evidence concerning nutritional factors, particularly lactation feeding that may reduce the loss of sow body reserves, affecting the growth of the next oocyte generation. In conclusion, decreasing birth weight and compromised immunity are subjects warranting investigation in the search for novel management tools. Furthermore, to increase litter uniformity, more focus should be placed on nutritional factors that affect IGF-1-driven follicle development before ovulation.Peer reviewe

IGF-1 concentration patterns and their relationship with follicle development after weaning in young sows fed different pre-mating diets

Piglet birth weight and within-litter birth weight variation are important for piglet survival and growth. Pre-mating diets may improve IGF-1 and follicle development during the weaning-to-oestrus interval (WEI) and subsequent piglet birth weight. The objective of this study was to modulate IGF-1 concentration during late lactation and the WEI of young sows by using specific pre-mating diets supplemented with microfibrillated cellulose (MF),l-carnitine (LC) orl-arginine (AR). A further objective was to investigate the relationship between IGF-1 and subsequent follicle development and oestrus and ovulation characteristics. In total, 56 first-parity and 20 second-parity sows in three consecutive batches were used for this experiment. Sows received daily either wheat (CON) or wheat plus MF, LC or AR at one of two supplementation levels (low and high) during last week of lactation and WEI. From weaning onwards, follicle and corpus luteum (CL) diameters were repeatedly measured with ultrasound. Blood samples were collected during the WEI for IGF-1 and on day 21 of pregnancy for progesterone analyses, respectively. Insulin-like growth factor-1 concentration, follicle diameter, oestrus and ovulation characteristics and CL diameter were not affected by pre-mating diets. Low IGF-1 class (= 8%,N= 28) had lower IGF-1 concentrations at weaning (167v. 214 ng/ml,P<0.05) compared to low LM loss sows (Peer reviewe