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Rudy K, Jeon D, Smith AA, Harding JCS, Pasternak JA. PRRSV-2 viral load in critical non-lymphoid tissues is associated with late gestation fetal compromise. Front Microbiol 2024; 15:1352315. [PMID: 38389522 PMCID: PMC10883647 DOI: 10.3389/fmicb.2024.1352315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Accepted: 01/26/2024] [Indexed: 02/24/2024] Open
Abstract
The impact of late gestation PRRSV-2 infection is highly variable within a litter, with a subset of fetuses displaying varying degrees of compromise following infection while others remain viable despite significant systemic viral load. To understand the underlying cause of this variation, we examined the susceptibility, distribution and impact of viral infection within non-lymphoid tissues. Samples of brain, heart, kidney, liver, lung, and skeletal muscle were obtained from fetuses of pregnant gilts at gestation day 86, and the presence and distribution of CD163+ cells within each tissue evaluated via immunohistofluorescence. Equivalent samples were collected from phenotypic extremes representing resistant, resilient and susceptible fetuses at 21 days following infection of pregnant gilts with PRRSV-2 at day 86 of gestation. Viral load and its impact in each tissue was evaluated by a combination of qPCR, in vitro viral recovery, and local expression of IFNG and CD163. Resting populations of CD163+ cells were observed in all six non-lymphoid tissues from healthy day 86 fetuses, though the apparent density and the morphology of positive cells varied between tissue. Viral RNA was detected in all six tissues derived from fetuses previously classified as highly infected, and infectious viral particles successfully recovered. Significantly more viral RNA was detected in heart, brain, lung and skeletal muscle of susceptible fetuses, relative to their viable counterparts. Infection was associated with an increase in the expression of CD163 in brain, kidney and lung. In addition, the presence of virus in each tissue coincided with a significant upregulation in the expression of IFNG, but the scale of this response was not associated with fetal susceptibility. Thus, PRRSV-2 is widely distributed across these susceptible non-lymphoid fetal tissues, and fetal outcome is associated with local viral load in critical fetal organs.
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Affiliation(s)
- K Rudy
- Department of Animal Sciences, Purdue University, West Lafayette, IN, United States
| | - D Jeon
- Department of Animal Sciences, Purdue University, West Lafayette, IN, United States
| | - A A Smith
- Department of Animal Sciences, Purdue University, West Lafayette, IN, United States
| | - J C S Harding
- Department of Large Animal Clinical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK, Canada
| | - J A Pasternak
- Department of Animal Sciences, Purdue University, West Lafayette, IN, United States
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Dervishi E, Bai X, Dyck MK, Harding JCS, Fortin F, Dekkers JCM, Plastow G. GWAS and genetic and phenotypic correlations of plasma metabolites with complete blood count traits in healthy young pigs reveal implications for pig immune response. Front Mol Biosci 2023; 10:1140375. [PMID: 36968283 PMCID: PMC10034349 DOI: 10.3389/fmolb.2023.1140375] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Accepted: 02/27/2023] [Indexed: 03/11/2023] Open
Abstract
Introduction: In this study estimated genetic and phenotypic correlations between fifteen complete blood count (CBC) traits and thirty-three heritable plasma metabolites in young healthy nursery pigs. In addition, it provided an opportunity to identify candidate genes associated with variation in metabolite concentration and their potential association with immune response, disease resilience, and production traits.Methods: The blood samples were collected from healthy young pigs and Nuclear Magnetic Resonance (NMR) was used to quantify plasma metabolites. CBC was determined using the ADVIA® 2120i Hematology System. Genetic correlations of metabolite with CBC traits and single step genome-wide association study (ssGWAS) were estimated using the BLUPF90 programs.Results: Results showed low phenotypic correlation estimates between plasma metabolites and CBC traits. The highest phenotypic correlation was observed between lactic acid and plasma basophil concentration (0.36 ± 0.04; p < 0.05). Several significant genetic correlations were found between metabolites and CBC traits. The plasma concentration of proline was genetically positively correlated with hemoglobin concentration (0.94 ± 0.03; p < 0.05) and L-tyrosine was negatively correlated with mean corpuscular hemoglobin (MCH; −0.92 ± 0.74; p < 0.05). The genomic regions identified in this study only explained a small percentage of the genetic variance of metabolites levels that were genetically correlated with CBC, resilience, and production traits.Discussion: The results of this systems approach suggest that several plasma metabolite phenotypes are phenotypically and genetically correlated with CBC traits, suggesting that they may be potential genetic indicators of immune response following disease challenge. Genomic analysis revealed genes and pathways that might interact to modulate CBC, resilience, and production traits.
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Affiliation(s)
- E. Dervishi
- Livestock Gentec, Department of Agriculture, Food and Nutritional Science, Faculty of Agricultural, Life and Environmental Sciences, University of Alberta, Edmonton, AB, Canada
| | - X. Bai
- Livestock Gentec, Department of Agriculture, Food and Nutritional Science, Faculty of Agricultural, Life and Environmental Sciences, University of Alberta, Edmonton, AB, Canada
| | - M. K. Dyck
- Livestock Gentec, Department of Agriculture, Food and Nutritional Science, Faculty of Agricultural, Life and Environmental Sciences, University of Alberta, Edmonton, AB, Canada
| | - J. C. S. Harding
- Department of Large Animal Clinical Sciences, University of Saskatchewan, Saskatoon, SK, Canada
| | - F. Fortin
- Centre de Developpement du porc du Quebec inc (CDPQ), Quebec City, QC, Canada
| | - J. C. M. Dekkers
- Department of Animal Science, Iowa State University, Ames, IA, United States
| | - G. Plastow
- Livestock Gentec, Department of Agriculture, Food and Nutritional Science, Faculty of Agricultural, Life and Environmental Sciences, University of Alberta, Edmonton, AB, Canada
- *Correspondence: G. Plastow,
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Suleman M, Malgarin CM, Detmer SE, Harding JCS, MacPhee DJ. The porcine trophoblast cell line PTr2 is susceptible to porcine reproductive and respiratory syndrome virus-2 infection. Placenta 2019; 88:44-51. [PMID: 31670096 DOI: 10.1016/j.placenta.2019.10.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 09/05/2019] [Accepted: 10/04/2019] [Indexed: 01/10/2023]
Abstract
INTRODUCTION Porcine reproductive and respiratory syndrome virus-2 (PRRSV-2) breaches the maternal-fetal interface (MFI) to infect porcine fetuses, yet the exact mechanism(s) of transmission is not understood. The objective of this study was to determine the susceptibility of porcine trophoblast cell line (PTr2) to PRRSV-2 infection to understand the potential role of the trophoblast in viral transmission to fetuses in vivo. METHODS PTr2 cells were exposed in vitro to PRRSV-2 and then subjected to immunofluorescence analysis (IF), flow cytometry (FCM), real-time quantitative PCR (RT-qPCR), transmission electron microscopy (TEM) and immunogold electron microscopy (IEM) to assess viral infection. The effects of PRRSV-2 on PTr2 cell cycle progression and apoptosis, as well as the ability of PTr2 cells to produce infectious viral particles were also examined. RESULTS PRRSV-2 was readily detected in PTr2 cells by IF, FCM, RT-qPCR, TEM and IEM techniques. RT-qPCR and FCM results of a time course of infection of PTr2 cells indicated PRRSV-2 load decreased over time after initial infection up to 72 h. PRRSV-2 infection altered PTr2 cell cycle with a selective increase of cells within the G2/M phase and also induced apoptosis. TEM and IEM demonstrated PRRSV-2 within and on the surface of PTr2 cells and PRRSV-2 virions released from PTr2 cells infected naïve MARC-145 cells inducing cytopathic effects. DISCUSSION Trophoblast cells are susceptible to PRRSV-2 infection and release live virions capable of inducing cytopathic effects in naïve cells. This suggests a possible mechanism by which PRRSV-2 can breach the MFI resulting in fetal infection and death.
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Affiliation(s)
- M Suleman
- Department of Large Animal Clinical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK, Canada; Department of Microbiology, Faculty of Veterinary Sciences, University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - C M Malgarin
- Department of Large Animal Clinical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK, Canada
| | - S E Detmer
- Department of Veterinary Pathology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK, Canada
| | - J C S Harding
- Department of Large Animal Clinical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK, Canada
| | - D J MacPhee
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK, Canada.
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Suleman M, Novakovic P, Malgarin CM, Detmer SE, Harding JCS, MacPhee DJ. Spatiotemporal immunofluorescent evaluation of porcine reproductive and respiratory syndrome virus transmission across the maternal-fetal interface. Pathog Dis 2019; 76:5050373. [PMID: 29986005 DOI: 10.1093/femspd/fty060] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 07/06/2018] [Indexed: 12/12/2022] Open
Abstract
Porcine reproductive and respiratory syndrome virus (PRRSV) infection causes severe reproductive failure characterized by high fetal morbidity and mortality leading to substantial economic losses to the swine industry. Evaluation of spatiotemporal transmission of PRRSV at the maternal-fetal interface (MFI) is critical for understanding fetal infection. Localization of PRRSV-2 strain NVSL 97-7895 at different regions of the MFI in 20 pregnant gilts at 2, 5, 8, 12 and 14 days post-inoculation (dpi) were analyzed by immunofluorescence (IF). Samples of MFI were collected from 15 inoculated and 5 control gilts and transplacental PRRSV transmission assessed in randomly selected fetuses from each litter. Localization of NVSL 97-7895 antigen immunoreactivity in the MFI was focused in three major areas: endometrial connective tissues (ENDO), the feto-maternal junction (FMJ) and fetal placenta (PLC). NVSL 97-7895 was detected at the FMJ by 2 dpi. At 2, 5 and 8 dpi, NVSL 97-7895 was localized within the ENDO and FMJ, whereas at 12 and 14 dpi, it was mainly localized in the PLC. Using a novel IF strategy for counting and size sorting NVSL 97-7895 viral antigen in situ, results of this study indicate that non-cell-associated mechanisms are involved in PRRSV transmission across the MFI.
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Affiliation(s)
- M Suleman
- Department of Large Animal Clinical Sciences
| | - P Novakovic
- Department of Large Animal Clinical Sciences
| | | | | | | | - D J MacPhee
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, 52 Campus Dr, University of Saskatchewan, Saskatoon, SK, S7N 5B4, Canada
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Putz AM, Harding JCS, Dyck MK, Canada P, Fortin F, Plastow GS, Dekkers JCM. 33 Quantifying Resilience from Individual Feed Intake Data in a Natural Disease Challenge Model for Growing Pigs. J Anim Sci 2018. [DOI: 10.1093/jas/sky073.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
| | | | - M K Dyck
- University of Alberta, Edmonton, AB, Canada
| | - P Canada
- PigGen Canada, Quelph, ON, Canada
| | - F Fortin
- Centre de developpement du porc du Quebec, Quebec City, QC, Canada
| | - G S Plastow
- Livestock Gentec Centre, University of Alberta, Edmonton, AB, Canada
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Putz AM, Harding JCS, Fortin F, Plastow G, Dekkers JCM. 036 A natural challenge model for disease resilience in wean-to-finish pigs. J Anim Sci 2017. [DOI: 10.2527/asasmw.2017.036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Bertolini F, Harding JCS, Mote B, Ladinig A, Plastow GS, Rothschild MF. Genomic investigation of piglet resilience following porcine epidemic diarrhea outbreaks. Anim Genet 2016; 48:228-232. [PMID: 27943331 PMCID: PMC7159462 DOI: 10.1111/age.12522] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/29/2016] [Indexed: 12/01/2022]
Abstract
Porcine epidemic diarrhea virus (PEDV) belongs to the Coronaviridae family and causes malabsorptive watery diarrhea, vomiting, dehydration and imbalanced blood electrolytes in pigs. Since the 1970s, PED outbreaks have become a source of problems in pig producing countries all over the world, causing large economic losses for pig producers. Although the infection in adults is not fatal, in naïve suckling piglets mortality is close to 100%. In this study, we investigated genome-wide differences between dead and recovered suckling piglets from commercial farms after PED outbreaks. Samples from 262 animals (156 dead and 106 recovered) belonging to several commercial lines were collected from five different farms in three different countries (USA, Canada and Germany) and genotyped with the porcine 80K SNP chip. Mean Fst value was calculated in 1-Mb non-overlapping windows between dead and recovered individuals, and the results were normalized to find differences within the comparison. Seven windows with high divergence between dead and recovered were detected-five on chromosome 2, one on chromosome 4 and one on chromosome 15-in total encompassing 152 genes. Several of these genes are either under- or overexpressed in many virus infections, including Coronaviridae (such as SARS-CoV). A total of 32 genes are included in one or more Gene Ontology terms that can be related to PED development, such as Golgi apparatus, as well as mechanisms generally linked to resilience or diarrhea development (cell proliferation, ion transport, ATPase activity). Taken together this information provides a first genomic picture of PEDV resilience in suckling piglets.
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Affiliation(s)
- F Bertolini
- Department of Animal Science, Iowa State University, Ames, IA, 50011-3150, USA
| | - J C S Harding
- Department of Large Animal Clinical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK, S7N 5B4, Canada
| | - B Mote
- Department of Animal Science, University of Nebraska, Lincoln, NE, 68583-0908, USA
| | - A Ladinig
- University Clinic for Swine, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine Vienna, Wien, 1210, Austria
| | - G S Plastow
- Livestock Gentec, Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, T6G 2R3, Canada
| | - M F Rothschild
- Department of Animal Science, Iowa State University, Ames, IA, 50011-3150, USA
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Hong L, Lunney JK, Wilkinson JW, Bao H, Ladinig A, Stothard P, Plastow G, Harding JCS. P6031 Confirmation of genome wide analysis of transcriptional responses to Porcine reproductive and respiratory syndrome virus infection in a pregnant gilt model. J Anim Sci 2016. [DOI: 10.2527/jas2016.94supplement4164x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Affiliation(s)
- Y. Huang
- Prairie Diagnostic Services; Saskatchewan Saskatoon Canada
| | - J. C. S. Harding
- Department of Large Animal Clinical Sciences; Western College of Veterinary Medicine; University of Saskatchewan; Saskatoon Saskatchewan Canada
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Abstract
Porcine periweaning failure-to-thrive syndrome (PFTS) is a clinical syndrome characterized by anorexia and progressive debilitation of newly weaned pigs. The objectives of the current case-control study were to describe the histopathologic features of PFTS in North America and test for selected pathogens in case and control pigs on 8 farms allegedly fulfilling the clinical definition of PFTS. Based on observations during farm visits, 5 farms fully met the case definition (PFTS farms), whereas 3 farms only partially fulfilled the definition (NON-PFTS farms). Necropsy and histopathologic examination were performed on case (n = 8 or 9) and control (n = 4) pigs from each farm. Superficial gastritis, which was mainly localized in the fundus and characterized by attenuation of superficial foveolar cells, was significantly more frequent in case pigs from PFTS farms compared with all the other pigs (odds ratio [OR], 16.7). The same was found for thymic atrophy (OR, 30.1) and small intestinal (SI) villous atrophy in the duodenum (OR, 28.7), jejunum (OR, 67.4), and ileum (OR, 56.3). All pigs with PFTS had at least 2 of these 3 lesions: gastritis, thymic atrophy, and SI villous atrophy. PFTS was not associated with any relevant porcine pathogen tested. We propose the diagnosis of PFTS be based on the fulfillment of the clinical case definition, the presence of the above lesions, and exclusion of other common swine diseases and pathogens. However, PFTS can be ruled out if debilitated pigs do not have at least 2 of the above 3 lesions.
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Affiliation(s)
- Y. Huang
- Department of Large Animal Clinical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
- Prairie Diagnostic Services, Inc, Saskatoon, Saskatchewan, Canada
| | - J. C. S. Harding
- Department of Large Animal Clinical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
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Serão NVL, Matika O, Kemp RA, Harding JCS, Bishop SC, Plastow GS, Dekkers JCM. Genetic analysis of reproductive traits and antibody response in a PRRS outbreak herd. J Anim Sci 2014; 92:2905-21. [PMID: 24879764 DOI: 10.2527/jas.2014-7821] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Porcine reproductive and respiratory syndrome (PRRS) is the most economically significant disease impacting pig production in North America, Europe, and Asia, causing reproductive losses such as increased rates of stillbirth and mummified piglets. The objective of this study was to explore the genetic basis of host response to the PRRS virus (PRRSV) in a commercial multiplier sow herd before and after a PRRS outbreak, using antibody response and reproductive traits. Reproductive data comprising number born alive (NBA), number alive at 24 h (NA24), number stillborn (NSB), number born mummified (NBM), proportion born dead (PBD), number born dead (NBD), number weaned (NW), and number of mortalities through weaning (MW) of 5,227 litters from 1,967 purebred Landrace sows were used along with a pedigree comprising 2,995 pigs. The PRRS outbreak date was estimated from rolling averages of farrowing traits and was used to split the data into a pre-PRRS phase and a PRRS phase. All 641 sows in the herd during the outbreak were blood sampled 46 d after the estimated outbreak date and were tested for anti-PRRSV IgG using ELISA (sample-to-positive [S/P] ratio). Genetic parameters of traits were estimated separately for the pre-PRRS and PRRS phase data sets. Sows were genotyped using the PorcineSNP60 BeadChip, and genome-wide association studies (GWAS) were performed using method Bayes B. Heritability estimates for reproductive traits ranged from 0.01 (NBM) to 0.12 (NSB) and from 0.01 (MW) to 0.12 (NBD) for the pre-PRRS and PRRS phases, respectively. S/P ratio had heritability (0.45) and strong genetic correlations with most traits, ranging from -0.72 (NBM) to 0.73 (NBA). In the pre-PRRS phase, regions associated with NSB and PBD explained 1.6% and 3% of the genetic variance, respectively. In the PRRS phase, regions associated with NBD, NSB, and S/P ratio explained 0.8%, 11%, and 50.6% of the genetic variance, respectively. For S/P ratio, 2 regions on SSC 7 (SSC7) separated by 100 Mb explained 40% of the genetic variation, including a region encompassing the major histocompatibility complex, which explained 25% of the genetic variance. These results indicate a significant genomic component associated with PRRSV antibody response and NSB in this data set. Also, the high heritability and genetic correlation estimates for S/P ratio during the PRRS phase suggest that S/P ratio could be used as an indicator of the impact of PRRS on reproductive traits.
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Affiliation(s)
- N V L Serão
- Department of Animal Science, Iowa State University, Ames 50011
| | - O Matika
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK
| | - R A Kemp
- Genesus, Oakville, MB R0H 0Y0, Canada
| | - J C S Harding
- Department of Large Animal Clinical Sciences, University of Saskatchewan, Saskatoon, SK S7N 5A1, Canada
| | - S C Bishop
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK
| | - G S Plastow
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB T6G 2R3, Canada
| | - J C M Dekkers
- Department of Animal Science, Iowa State University, Ames 50011
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Foxcroft GR, Dixon WT, Dyck MK, Novak S, Harding JCS, Almeida FCRL. Prenatal programming of postnatal development in the pig. Soc Reprod Fertil Suppl 2009; 66:213-231. [PMID: 19848290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Studies of low birth weight offspring have a long history in pig science. These pigs have reduced growth potential and poor carcass quality compared to their higher birth weight littermates. In contemporary commercial sows with between 10 and 15 total pigs born/litter, between-litter differences in average birth weight appear to make the largest contribution to variation in postnatal growth performance, independent of numbers born. Low birth weight is a characteristic of a subpopulation of these sows, likely as a consequence of an imbalance between ovulation rate and uterine capacity due to ongoing selection for litter size. Based on experimental studies, we hypothesize that increased crowding at day 30 of gestation primarily affects placental development and persistent negative impacts on placental growth then affect fetal development. However, embryonic myogenic gene expression is already affected at day 30. Latent effects of metabolic state on oocyte quality and early embryonic development have also been reported. In contrast to effects of uterine crowding, the embryo is primarily affected by previous catabolism. The large body of literature on gene imprinting, and the interactions between metabolism, nutrition, and methylation state, suggest that classic imprinting mechanisms may be involved. However, the potential use of genomics, epigenomics, nutrigenomics, and proteomics to investigate these mechanisms brings new demands on experimental design and data management that present a considerable challenge to the effectiveness of future research on prenatal programming in the pig.
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Affiliation(s)
- G R Foxcroft
- Swine Reproduction-Development Program, Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, T6G 2P5, Canada.
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