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Almost all the fertility parameters in sows (reproductive and productive) may be affected by different infectious diseases. Changes in reproductive parameters may also occur without the appearance of appreciable pathological findings or with clinical signs often overlapping or similar to different diseases or pathogens. All the clinical aspects and...
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... Several samples of live piglets tested positive for RVFV antibodies and antigen/RNA, whereas a small number of aborted fetuses did. Both viral and non-infectious factors, as well as their pathophysiology, may contribute to these reproductive failures (Pozzi and Alborali 2012). It was established that RVFV was the most likely cause since the pigs were taken from an enclosed breeding herd that adhered to stringent biosecurity and disease control laws and regulations. ...
RVFV, also known as the Rift Valley fever virus (genus Phlebovirus family Phenuiviridae), is an arbovirus infection that causes Rift Valley fever (RVF). Whenever RVFV shows up, it spreads epidemics among the local population and causes epizootics in livestock. Animals and people in Africa and the Arabian Peninsula have been affected by RVF, a disease spread by mosquitoes and caused by the RVFV. In RVF epidemics, animals contract the virus through mosquito bites, leading to substantial viral amplification and spread to nearby regions through livestock movement and mosquito migration. Following animal slaughter or the handling of embryonic materials, direct contact with infected animals or mosquito bites are the subsequent ways in which the virus is transmitted to humans. Real-time polymerase chain reaction (RT-PCR) reverse transcription can be used to identify RVFV. The most common symptom of RVF in pregnant animals is an abrupt, violent abortion. Animals with the virus may have up to 100% abortion rates because it directly targets the developing embryo. In young animals, the mortality rate can reach 100%. When this disease progresses from apparent to acute, it causes fever, weakness, and bloody diarrhea in adults, but it causes fever, loss of appetite, and death in young animals. RVFV infections in humans usually show no symptoms at all and go away on their own. After an incubation period of 4-6 days, symptoms of RVF, including fever, chills, fragility, headache, and joint and muscular pain, become apparent. An almost simultaneous, marked increase in the number of abortions performed on pregnant ruminants is the telltale sign of an RVF epizootic. Known as "abortion storms," these widespread abortion occurrences allow one to distinguish RVF from several other common infectious causes of abortion in ruminants, including toxoplasmosis, salmonellosis, chlamydiosis and Q fever (Coxiella burnettii). The one health approach is essential in combating this rapidly spreading infection. RVF can be effectively managed and prevented by focusing on the interconnectedness of human, animal, and environmental health.
... Early abortions may result in fetal reabsorption that could go unnoticed and be misinterpreted as infertility, and contribute to the underestimation of the actual impact of PPVs in reproductive syndromes. Additionally, this study did not investigate anatomopathological aspects, preventing conclusions on the real pathogenetic contribution of the detected pathogens, nor did it account for non-infective causes of reproductive problems [70]. Environmental factors, toxins, poor management, and other stressors could have been involved in the clinical episodes in farms negative to all tested infective agents, thus inflating the study denominators. ...
Successful reproductive performance is key to farm competitiveness in the global marketplace. Porcine parvovirus 1 (PPV1) has been identified as a major cause of reproductive failure, and since 2001 new species of porcine parvoviruses, namely PPV2–7, have been identified, although their role is not yet fully understood yet. The present study aimed to investigate PPVs’ presence in reproductive failure outbreaks occurring in 124 farms of northern Italy. Fetuses were collected from 338 sows between 2019 and 2021 and tested for PPVs by real-time PCR-based assays and for other viruses responsible for reproductive disease. At least one PPV species was detected in 59.7% (74/124) of the tested farms. In order, PPV1, PPV5, PPV6, PPV7 and PPV4 were the most frequently detected species, whereas fewer detections were registered for PPV2 and PPV3. Overall, the new PPV2–7 species were detected in 26.6% (90/338) of the cases, both alone or in co-infections: PCV-2 (7.1%, 24/338), PCV-3 (8.2%, 28/338), and PRRSV-1 (6.2%, 21/338) were frequently identified in association with PPVs. Single PPVs detections or co-infections with other agents commonly responsible for reproductive failure should encourage future studies investigating their biological, clinical, and epidemiological role, for a better preparedness for potential emerging challenges in intensive pig production.
... Several samples of live piglets tested positive for RVFV antibodies and antigen/RNA, whereas a small number of aborted fetuses did. Both viral and non-infectious factors, as well as their pathophysiology, may contribute to these reproductive failures (Pozzi and Alborali 2012). It was established that RVFV was the most likely cause since the pigs were taken from an enclosed breeding herd that adhered to stringent biosecurity and disease control laws and regulations. ...
... The live piglets tested RVFV antibody and antigen/RNA positive in various samples, while the aborted foetuses also tested positive for viral RNA in a few samples (Table 2; Figures 1, 4 and 5; Tables S1 and S2). Reproductive failures like these may result from non-infectious or infectious causes and their resultant pathogenesis, or both [37]. However, RVFV was the most likely cause because common infectious pathogens associated with stillbirth, mummies, embryonal deaths and infertility (SMEDI) were unlikely, since the pigs were sourced from a closed breeding herd with strict biosecurity and adherence to disease control regulations, conditions which are also protective against management causes. ...
Rift valley fever (RVF), caused by the RVF virus (RVFV), is a vector-borne zoonotic disease that primarily affects domestic ruminants. Abortion storms and neonatal deaths characterise the disease in animals. Humans develop flu-like symptoms, which can progress to severe disease. The susceptibility of domestic pigs (Sus scrofa domesticus) to RVFV remains unresolved due to conflicting experimental infection results. To address this, we infected two groups of pregnant sows, neonates and weaners, each with a different RVFV isolate, and a third group of weaners with a mixture of the two viruses. Serum, blood and oral, nasal and rectal swabs were collected periodically, and two neonates and a weaner from group 1 and 2 euthanised from 2 days post infection (DPI), with necropsy and histopathology specimens collected. Sera and organ pools, blood and oronasorectal swabs were tested for RVFV antibodies and RNA. Results confirmed that pigs can be experimentally infected with RVFV, although subclinically, and that pregnant sows can abort following infection. Presence of viral RNA in oronasorectal swab pools on 28 DPI suggest that pigs may shed RVFV for at least one month. It is concluded that precautions should be applied when handling pig body fluids and carcasses during RVF outbreaks.
... Using a single-dose vaccine that promotes protective immunity against infectious disease would significantly benefit the pig industry. Moreover, formulating vaccines so that they can be administered via the intramuscular (i.m.) route yet trigger uterine and systemic immunity would help protect pig reproductive health (19). Because the majority of commercial pigs are bred by artificial insemination (AI) (20), current husbandry practices allow routine access to the uterus during each reproductive cycle. ...
An effective single-dose vaccine that protects the dam and her suckling offspring against infectious disease would be widely beneficial to livestock animals. We assessed whether a single-dose intramuscular (i.m.) porcine epidemic diarrhea virus (PEDV) vaccine administered to the gilt 30 days post-breeding could generate mucosal and systemic immunity and sufficient colostral and mature milk antibodies to protect suckling piglets against infectious challenge. The vaccine was comprised of polymeric poly-(lactide-co-glycolide) (PGLA)-nanoparticle (NP) encapsulating recombinant PEDV spike protein 1 (PEDVS1) associated with ARC4 and ARC7 adjuvants, a muramyl dipeptide analog and a monophosphoryl lipid A (MPLA) analog, respectively (NP-PEDVS1). To establish whether prior mucosal exposure could augment the i.m. immune response and/or contribute to mucosal tolerance, gilts were immunized with the NP-PEDVS1 vaccine via the intrauterine route at breeding, followed by the i.m. vaccine 30 days later. Archived colostrum from gilts that were challenged with low-dose PEDV plus alum was used as positive reference samples for neutralizing antibodies and passive protection. On day 100 of gestation (70 days post i.m. immunization), both vaccinated groups showed significant PEDVS1-specific IgG and IgA in the serum, as well as in uterine tissue collected on the day of euthanasia. Anti-PEDVS1 colostral IgG antibody titers collected at farrowing were significantly higher relative to the negative control gilts indicating that the NP vaccine was effective in contributing to the colostral antibodies. The PEDVS1-specific colostral IgA and anti-PEDVS1 IgG and IgA antibodies in the mature milk collected 6 days after farrowing were low for both vaccinated groups. No statistical differences between the vaccinated groups were observed, suggesting that the i.u. priming vaccine did not induce mucosal tolerance. Piglets born to either group of vaccinated gilts did not receive sufficient neutralizing antibodies to protect them against infectious PEDV at 3 days of age. In summary, a single i.m. NP vaccine administered 30 days after breeding and a joint i.u./i.m. vaccine administered at breeding and 30 days post-breeding induced significant anti-PEDVS1 immunity in systemic and mucosal sites but did not provide passive protection in suckling offspring.
... These findings are similar to a report in Swedish sows, the common morbidities include mastitis, metritis and agalactia complex (MMA) and farrowing problems (Olson et al, 2019). In a review, Pozzi and Alborali, 2012, pointed out that reproductive diseases in sows were mainly of infectious origin. Such infections negatively affected porcine reproductive and productive parameters. ...
A cross-sectional study was conducted among commercial pig farmers in the Ejisu Municipality to investigate reproductive performance, piglet mortality, and reproductive health problems on their farms. Questionnaires designed to obtain information on reproductive performance and reproductive health problems were administered to a total of 50 randomly selected pig farmers. Three farms were randomly selected to monitor farrowing and pre-weaning piglet mortality. The farrowing records of a minimum of 10 sows on each farm were taken, and the piglets followed up to the point of weaning by six weeks. Records of piglet mortalities and their causes were retrieved from farm records or post mortem reports. The mean litter size, stillbirth per litter, piglet birth weight (Kg), weaning to estrus interval, and gestation period were 9.5± 1.4, 1.6 ± 0.2, 1.0 ± 0.1, .7±1.0 days, and 115.1± 2.6 days, respectively. The pre-weaning mortality (%) at day 42 was 18.7 and ranged from 7.3-28.3. Within the first two days post farrowing, mechanical crushing (8.9%) of piglets by sows and piglet starvation (7.2%), while diarrhea (2.5%) and piglet anemia (1.5%) accounted for mortalities within the first two weeks of life. Reproductive health problems by frequency of occurrence included mastitis (23%), agalactia (18%), stillbirths (18%), repeat breeders (14%) and dystocia (14%). The study concluded that the reproductive performance of sows was satisfactory, while pre-weaning piglet mortality was high. It is recommended to intensify extension education on the management of piglets after farrowing.
... Further, market intervention may be needed to stabilize pork production and reduce pork price fluctuations. To better control sow reproductive diseases such as Porcine Reproductive and Respiratory Syndrome, which can damage the productive performance of sows and cause great economic losses, approaches including antibiotic therapy, prophylaxis, and immunization programs should be taken into account [37] . ...
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•Large-scale industrial pork production enterprises are preferred in China in the future.
•Challenges to green pork production include emissions, feed shortage and residues.
•Potential solutions to green production include precise feeding and manure recycling.
This paper reviews the changes in pork production in China, the largest pork producing and consuming nation in the world. The pork sector in China has changed dramatically since the 1990s, with large-scale intensive pork production systems replacing the former, exclusively family-based pork production systems. Modern breeding, feeding, vaccinating, and management technologies are widely used now. However, smallholders still account for a large proportion of the total production. The intensification and specialization of the pork sector is expected to continue in the future, but there is increasing awareness and pressure to develop more environmentally-sustainable production systems. The relative shortage of domestically produced feed, the low utilization efficiency of feed ingredients, the large emissions of nitrogen and phosphorus to the environment, the high use of antibiotics, and the presence of residual metals in manures are very large challenges for the pork sector nowadays. To solve these problems, techniques including new feed resource utilization, precise feeding, low-protein diets, alternatives to antibiotics and increased manure recycling are all important topics and research directions today. With new techniques and management approaches, it is possible to build more sustainable pork production systems in China.
... Leptospirosis is a notifiable disease in Israel (22); it may seriously affect swine production (2,4,23,24); and it is considered a professional hazard (2,4) and indeed infections between swine workers and pigs have been recorded in the past (8). Despite pig farming in Israel is limited, this work demonstrated prevalence of Leptospira in swine farms; 12 out of 21 examined (57%) were positive with 23.8% of positive samples in general and 41.6% positivity within Research Articles positive farms, with almost exclusive involvement of canicola serovar. ...
Twenty one pig farms, comprising about 14,400 sows and 90,000 fattening pigs, were examined relative to Leptospira serological positivity in fattening pigs. Twelve farms (57.14%) were positive with average of 41.67% positive samples. L. canicola was the predominant serovar (100%), with a few cross-reactions for other serovars. There was as strong correlation between average number of positive samples and number of sows in farm (R 2 = 0.9615). Number of positive samples was significantly higher in farms not vaccinating sows (P = 0.0059); practicing natural insemination (P = 0.0280); keeping fattening pigs on a full floor (P = 0.0019); presence of dogs (P = 0.0002); farms with high proximity to each other and shared infrastructures like perimetral walls, sewage, roads, workers (P = 0.0005). In such a situation, swine breeders should vaccinate their breeders population, their dogs and implement management measures. Leptospirosis is a notifiable disease in Israel.
... In fact, studies in rats and rabbits have shown that the uterus may be a suitable immunization site as vaccines delivered to the uterus triggered a measurable antigen-specific systemic and local humoral immunity (6)(7)(8). Because a number of economically important diseases in pigs such as porcine parvovirus (PPV) and porcine reproductive and respiratory syndrome virus (PRRSV) impact reproduction, it may be very beneficial to have a mode of vaccine delivery that triggers a strong mucosal immune response in the uterus to protect growing fetuses (9). For livestock systems that use natural breeding, the uterus is not readily accessible for immunization. ...
To protect the health of sows and gilts, significant investments are directed toward the development of vaccines against infectious agents that impact reproduction. We developed an intrauterine vaccine that can be delivered with semen during artificial insemination to induce mucosal immunity in the reproductive tract. An in vitro culture of uterine epithelial cells was used to select an adjuvant combination capable of recruiting antigen-presenting cells into the uterus. Adjuvant polyinosinic:polycytidylic acid (poly I:C), alone or in combination, induced expression of interferon gamma, tumor necrosis factor alpha, and select chemokines. A combination adjuvant consisting of poly I:C, host defense peptide and polyphosphazene (Triple Adjuvant; TriAdj), which previously was shown to induce robust mucosal and systemic humoral immunity when administered to the uterus in rabbits, was combined with boar semen to evaluate changes in localized gene expression and cellular recruitment, in vivo. Sows bred with semen plus TriAdj had decreased γδ T cells and monocytes in blood, however, no corresponding increase in the number of monocytes and macrophages was detected in the endometrium. Compared to sows bred with semen alone, sows bred with semen plus TriAdj showed increased CCL2 gene expression in the epithelial layer. These data suggest that the adjuvants may further augment a local immune response and, therefore, may be suitable for use in an intrauterine vaccine. When inactivated porcine parvovirus (PPV) formulated with the TriAdj was administered to the pig uterus during estrus along with semen, we observed induction of PPV antibodies in serum but only when the pigs were already primed with parenteral PPV vaccines. Recombinant protein vaccines and inactivated PPV vaccines administered to the pig uterus during breeding as a primary vaccine alone failed to induce significant humoral immunity. More trials need to be performed to clarify whether repeated intrauterine vaccination can trigger strong humoral immunity or whether the primary vaccine needs to be administered via a systemic route to promote a mucosal and systemic immune response.
... The parameters were selected based on the most common clinical signs on herds affected by PRRSV infection (Pozzi and Alborali, 2012;Zimmerman et al., 2012). More specifically, significant changes were monitored on a week basis for number of abortions, pre-weaning mortality rate (PWM) and prenatal losses (difference between 'total number of pigs born per litter' and 'number of pigs born alive per litter'). ...
... Continuous evaluation of animal health is essential for sustainable production (Weary et al., 2009), allowing early detection of deviations, and subsequently quick implementation of applicable intervention methods. The production indicators used in this study were chosen based on their biological relevance to PRRSV infection in swine breeding herds Pozzi and Alborali, 2012;Zimmerman et al., 2012). Monitoring production data was useful to detect signals associated with PRRSV infection, but in daily production this tool also could assist the identification of non-infectious sources of variation or another infectious disease, since production indicators are not disease-specific. ...
Porcine reproductive and respiratory syndrome virus (PRRSv) causes substantial economic impact due to significant losses in productivity. Thus, measuring changes in farm productivity before and after PRRS infection enables quantifying the production and economic impact of outbreaks. This study assessed the application of exponentially weighted moving average (EWMA), a statistical process control method, on selected production data (number of abortions, pre-weaning mortality rate and prenatal losses) to supplement PRRS surveillance programs by detecting significant deviations on productivity in a production system with 55,000 sows in 14 breed-to-wean herds in Minnesota, U.S.A. Weekly data from diagnostic monitoring program (available through the Morrison's Swine Health Monitoring Project) implemented on the same herds was used as reference for PRRS status. The time-to-detect, percentage of early detection of PRRSv-associated productivity deviations, and relative sensitivity and specificity of the production data monitoring system were determined relative to the MSHMP. The time-to-detect deviations on productivity associated with PRRS outbreaks using the EWMA method was −4 to −1 weeks (interquartile range) for the number of abortions, 0–0 for preweaning mortality and −1 to 3 weeks for prenatal losses compared to the date it was reported in the MSHMP database. Overall, the models had high relative sensitivity (range 85.7–100%) and specificity (range 98.5%–99.6%) when comparing to the changes in PRRS status reported in the MSHMP database. In summary, the use of systematic data monitoring showed a high concordance compared to the MSHMP-reported outbreaks indicating that on-farm staff and veterinary oversight were efficient to detect PRRSv, but can be more efficient if they were monitoring closely the frequency of abortions. The systematic monitoring of production indicators using EWMA offers opportunity to standardize and semi-automate the detection of deviations on productivity associated with PRRS infection, offering opportunity to early detect outbreaks and/or to quantify the production losses attributed to PRRS infection.
