Norwegian Pigs Research Articles

Mutations with known links to pork quality defects in Norwegian and German pig populations

ABSTRACT With heritable PSE (hal+) being largely eradicated in many countries, pork quality defects and their linkage to known mutations have received less attention in the last decade. We address this by mapping the frequency of four known mutations (200Q, 199 V, hal+, PHKG1) in heterogenous Norwegian and German pig populations (n = 136/61). Genotyping for mutations was done by PCR-RFLP analyses and Illumina chip genotyping. We found a high prevalence of pigs with at least one of the four tested mutations for Norwegian and German samples (60%, 77%). For Norwegian samples, we confirm known links of 200Q and PHKG1 with Hampshire and Duroc genetics, respectively. For Germany, we show that Piétrain pigs can still be heterozygous carriers of hal + . In all, our data points to a relatively high abundance of mutations that affect pork quality in both countries. The high prevalence of individual mutations may contribute to recent ham quality defects.

Highly conserved composite transposon harbouring aerobactin iuc3 in Klebsiella pneumoniae from pigs.

Klebsiella pneumoniae is an important opportunistic pathogen associated with severe invasive disease in humans. Hypervirulent K. pneumoniae, which are K. pneumoniae with several acquired virulence determinants such as the siderophore aerobactin and others, are more prominent in countries in South and South-East Asia compared to European countries. This Klebsiella pathotype is capable of causing liver abscesses in immunocompetent persons in the community. K. pneumoniae has not been extensively studied in non-human niches. In the present study, K. pneumoniae isolated from caecal samples (n=299) from healthy fattening pigs in Norway were characterized with regard to population structure and virulence determinants. These data were compared to data from a previous study on K. pneumoniae from healthy pigs in Thailand. Lastly, an in-depth plasmid study on K. pneumoniae with aerobactin was performed. Culturing and whole-genome sequencing was applied to detect, confirm and characterize K. pneumoniae isolates. Phylogenetic analysis described the evolutionary relationship and diversity of the isolates, while virulence determinants and sequence types were detected with Kleborate. Long-read sequencing was applied to obtain the complete sequence of virulence plasmids harbouring aerobactin. A total of 48.8 % of the investigated Norwegian pig caecal samples (n=299) were positive for K. pneumoniae. Acquired virulence determinants were detected in 72.6 % of the isolates, the most prominent being aerobactin (69.2 %), all of which were iuc3. In contrast, only 4.6 % of the isolates from Thailand harboured aerobactin. The aerobactin operon was located on potentially conjugative IncFIBK/FIIK plasmids of varying sizes in isolates from both countries. A putative, highly conserved composite transposon with a mean length of 16.2 kb flanked by truncated IS3-family IS407-group insertion sequences was detected on these plasmids, harbouring the aerobactin operon as well as several genes that may confer increased fitness in mammalian hosts. This putative composite transposon was also detected in plasmids harboured by K. pneumoniae from several countries and sources, such as human clinical samples. The high occurrence of K. pneumoniae harbouring aerobactin in Norwegian pigs, taken together with international data, suggest that pigs are a reservoir for K. pneumoniae with iuc3. Truncation of the flanking ISKpn78-element suggest that the putative composite transposon has been permanently integrated into the plasmid, and that it is no longer mobilizable.

Comparative Genome Sequence Analysis of Actinobacillus pleuropneumoniae Serovar 8 Isolates From Norway, Denmark, and the United Kingdom Indicates Distinct Phylogenetic Lineages and Differences in Distribution of Antimicrobial Resistance Genes.

Actinobacillus pleuropneumoniae is the etiological agent of porcine pleuropneumonia, a disease of major impact on pig health, welfare, and productivity globally. Serovar 8 (APP) is the predominant clinical serovar in Norway and the United Kingdom (UK), and has been isolated from clinical cases in Denmark. The primary objective of this study was to characterize the genetic variability of isolates of A. pleuropneumoniae APP8 in the Norwegian population. The secondary objectives were to determine the within-host variability of APP8; to compare the APP8 bacterial populations in Norway, Denmark, and the UK, including antimicrobial resistance (AMR) gene profiles and to assess the effect of national differences in antimicrobial drug use and restricted animal movement on the occurrence of resistance. Isolates of APP8 from the UK (n=67), Denmark (n=22), and Norway (n=123) collected between 1983 and 2020 were compared using whole genome sequencing. To investigate genetic variability within individual hosts, an additional 104 APP8 isolates from the lungs of six Norwegian pigs were compared. Very low within-host variation was observed (≤ 2 single nucleotide polymorphisms). The phylogeny of 123 Norwegian APP8 isolates from 76 herds revealed some within-herd genetic variation, but substantial geographical clustering. When inferring the relatedness of the three international APP8 collections, the topology highlighted the existence of two distinct monophyletic branches characterized by the Norwegian and UK isolates, respectively. Three Danish isolates were scattered across the UK branch, whereas the remaining 19 Danish isolates clustered in two monophyletic groups nested in the Norwegian branch. Coalescence analysis, performed to estimate the divergences from a common ancestor, indicated a last common ancestor several centuries ago. The phylogenetic analyses also revealed striking differences in occurrence of AMR genes, as these were 23-times more prevalent among the UK isolates than among the Norwegian isolates. An increased understanding of the effects of population strategies is helpful in surveillance and control of infectious diseases.

Longitudinal Projection of Herd Prevalence of Influenza A(H1N1)pdm09 Virus Infection in the Norwegian Pig Population by Discrete-Time Markov Chain Modelling

In order to quantify projections of disease burden and to prioritise disease control strategies in the animal population, good mathematical modelling of infectious disease dynamics is required. This article investigates the suitability of discrete-time Markov chain (DTMC) as one such model for forecasting disease burden in the Norwegian pig population after the incursion of influenza A(H1N1)pdm09 virus (H1N1pdm09) in Norwegian pigs in 2009. By the year-end, Norway’s active surveillance further detected 20 positive herds from 54 random pig herds, giving an estimated initial population prevalence of 37% (95% CI 25–52). Since then, Norway’s yearly surveillance of pig herd prevalence has given this study 11 years of data from 2009 to 2020 to work with. Longitudinally, the pig herd prevalence for H1N1pdm09 rose sharply to >40% in three years and then fluctuated narrowly between 48% and 49% for 6 years before declining. This initial longitudinal pattern in herd prevalence from 2009 to 2016 inspired this study to of test the steady-state discrete-time Markov chain model in forecasting disease prevalence. With the pig herd as the unit of analysis, the parameters for DTMC came from the initial two years of surveillance data after the outbreak, namely vector prevalence, first herd incidence and recovery rates. The latter two probabilities formed the fixed probability transition matrix for use in a discrete-time Markov chain (DTMC) that is quite similar to another compartmental model, the susceptible–infected–susceptible (SIS) model. These DTMC of predicted prevalence (DTMCP) showed good congruence (Pearson correlation = 0.88) with the subsequently observed herd prevalence for seven years from 2010 to 2016. While the DTMCP converged to the stationary (endemic) state of 48% in 2012, after three time steps, the observed prevalence declined instead from 48% after 2016 to 25% in 2018 before rising to 29% in 2020. A sudden plunge in H1N1pdm09 prevalence amongst Norwegians during the 2016/2017 human flu season may have had a knock-on effect in reducing the force of infection in pig herds in Norway. This paper endeavours to present the discrete-time Markov chain (DTMC) as a feasible but limited tool in forecasting the sequence of a predicted infectious disease’s prevalence after it’s incursion as an exotic disease.

Findings and measures to eradicate methicillin resistant Staphylococcus aureus clonal complex 7 spa-type t091 in two Norwegian pig farms: a case report

BackgroundThe Norwegian LA-MRSA surveillance and control strategy in pig farms has been largely successful in preventing the establishment of MRSA in the pig population by identifying positive pig herds and eradicating MRSA from these. It can, however, be challenging to determine whether a particular type of MRSA is livestock-associated, particularly in cases where there is little evidence available to aid in classification.Case presentationIn two Norwegian pig farms linked by trade of live pigs, MRSA CC7 t091 was found in samples from pigs and their environment. Longitudinal sampling, with a time interval of 25 days, in one farm demonstrated an increase in samples positive for MRSA CC7 t091, supporting a classification of the finding as livestock associated. Measures to eradicate MRSA from both farms were imposed by the National Food Safety Authority. Different measures of MRSA sanitation were applied in the two farms, and MRSA was successfully eradicated from both farms.ConclusionsA high-cost, labor intensive and a lower-cost, less labor intensive MRSA eradication protocol, both including total depopulation and repopulation were successful in eradicating MRSA CC7 t091 from two case farms.

Successful eradication of Mycoplasma hyopneumoniae from the Norwegian pig population \u2013 10\u2009years later

BackgroundMycoplasma hyopneumoniae (Mhyo) is the causative agent of enzootic pneumonia in pigs which adversely affects animal health and welfare, in addition to causing considerable economical losses. This paper presents the implementation of the national Mhyo eradication program in Norway, the subsequent population wide surveillance and documentation on the current freedom from Mhyo in the Norwegian pig population.In 1994, the Board of The Norwegian Pig Health Service decided on conducting a national surveillance and eradication program for Mhyo. The program aimed for population wide freedom from Mhyo, based on serological surveillance. A partial depopulation program was initiated in all Mhyo positive farrow-to-feed and farrow-to-finish herds. Total depopulation was performed in all positive finisher herds.ResultsFrom 1994 to 2009, a total of 138,635 pigs in 3211 herds were serologically tested for the presence of antibodies against Mhyo. Of these, 5538 (4%) individual samples and 398 (12.4%) of the herds were defined as positive. In 2009, the Norwegian pig population was declared free from Mhyo, and has been so since then. From 2009 through 2019, a total of 44,228 individual serum samples have been analyzed for the presence of antibodies against Mhyo and found negative in the National surveillance program.ConclusionEradication of Mhyo infections has resulted in improved health and welfare of the Norwegian pig population. The success of the strategy is based on numerous factors, such as moderate to low prevalence of the agent, well documented and effective eradication protocols, accurate diagnostic tests, relatively small herds, low herd density in most parts of the country and negligible import of live pigs. In addition, economic benefit due to a premium on pigs marketed from herds free from Mhyo, a well-structured commercial pig population, and finally, the loyalty and significant effort of farmers, abattoir employees and veterinarians were crucial factors. To maintain the infection-free status at national level, a continuous alertness is required in the future to discover possible Mhyo infections and ensure rapid sampling and diagnostics. Any findings of Mhyo positive pig herds in Norway will result in immediate eradication.

Verification of lean meat percentage estimation formulae for pig carcass classification in Croatia

Submitted 2020-07-23 | Accepted 2020-08-16 | Available 2020-12-01 https://doi.org/10.15414/afz.2020.23.mi-fpap.265-268 The study was performed on 136 pig carcasses representing the Croatian pig population with regards to the breed structure. The carcasses were dissected according to the EU reference method and lean meat percentage was estimated using the Hennessy Grading Probe (HGP7) device and the “Two points” (ZP) method. Comparison of lean meat percentage obtained by dissection and two prediction methods showed significant differences in estimating the lean meat percentage of pig carcasses (P <0.05). The distribution of carcasses according to SEUROP system showed a difference in the classification depending on the applied method, indicating a need for adjustment of current formulae for lean meat percentage estimation in Croatia. Keywords: pig, carcass, lean meat percentage, dissection, EU reference method References Causeur, D., Daumas, G., Dhorne, T., Engel, B., Fonti-Furnols, M., Hojsgaard, S. (2003). Statistical handbook for assessing pig classification methods: recommendations from the ‘EUPIGCLASS’ project group. EC working document. EEC Commission. (1994). Commission Regulation (EC) No 3127/94 of 20 December 1994 amending Regulation (EC) No 2967/85 laying Dowd detailed rules for the application of the Community scale for grading pig carcases. Official Journal of the European Communities, 43-44. EEC Commission. (2006). Commission Regulation (EC) No 1197/2006 of 7 August 2006 amending regulation (EEC) No 2967/85 laying down detailed rules for the application of the Community scale for grading pig carcasses. Official Journal of the European Union, 49, L 217, 8/8/2006, 6-7. EEC Commission. (2008). Commission Regulation (EC) No. 1249/2008 (2008, 12.16). of 10 December 2008 laying down detailed rules on the implementation of the community scales for the classification of beef, pig and sheep carcases and the reporting of prices thereof. Official Journal of the European Union, L337. EEC Commission. (2013). Regulation (EU) No. 1308/2013 (2013, 12.20). of the European Parliament and of the Council of 17 December 2013 establishing a common organisation of the markets in agricultural products and repealing Council Regulations (EEC) No 922/72, (EEC) No 234/79, (EC) No 1037/2001 and (EC) No 1234/2007. Official Journal of the European Union, L347. EEC Commission. (2017). Commission Implementng Regulaton (EU) 2017/1184 of 20 April 2017 laying down rules for the applicaton of Regulaton (EU) No 1308/2013 of the European Parliament and of the Council as regards the Union scales for the classifcaton of beef, pig and sheep carcasses and as regards the reportng of market prices of certain categories of carcasses and live animals. Official Journal of the European Union. htps://eur-lex.europa.eu/legal-content/EN/TXT/?uri= CELEX%3A32017R1184. Font-i-Furnols, M., Candek-Potokar, M., Daumas, G., Gispert, M., Judas, M. & Seynaeve, M. (2016). Comparison of national ZP equations for lean meat percentage assessment in SEUROP pig classification. Meat science, 113, 1-8. Gangsei, L. E., Kongsro, J., Olsen, E. V., Roe, M., Alvseike, O. & Saebo, S. (2016). Prediction precision for lean meat percentage in Norwegian pig carcasses using ‘Hennessy grading probe 7’: Evaluation of methods emphasized at exploiting additional information from computed tomography. Acta Agriculturae Scandinavica, Section A — Animal Science, 66(1), 17-24. Kusec, G., Kralik, G., Djurkin, I., Margeta, V., Maltar, Z. & Petricevic, A. (2006). Comparison of different methods for lean percentage evaluation in pig carcasses. Acta Agraria Kaposvariensis, 10(2), 57-62. Kusec, G., Đurkin, I., Petricevic, A., Kralik, G., Maltar, Z., Margeta, V. & Hanžek, D. (2007). Equations for lean share estimation in swine carcasses in Croatia. Poljoprivreda, 13 (1), 70-73. Kusec, G., Đurkin, I., Petricevic, A., Kralik, G., Maltar, Z. & Margeta, V. (2009). Carcass leanness of pigs in Croatia estimated by EU referent method. Italian Journal of Animal Science, 8(3), 249-251. Kusec, G., Đurkin, I., Lukic, B., Radisic, Ž., Petricevic, A. & Maltar, Z. (2011). The Equation for Prediction of Lean Meat Percentage by Hennessy Grading Probe in Croatia. Agriculturae Conspectus Scientificus, 76 (4), 329-331. NN 71/2018 Pravilnik o razvrstavanju i oznacivanju goveđih, svinjskih i ovcjih trupova te oznacivanju mesa koje potjece od goveda starih manje od 12 mjeseci. Sack, E. (1983). Using instruments to grade pork sides. Fleischwirtschaft, 63(3), 372–379. Vester-Christensen, M., Erbou, S.G.H., Hansen, M.F., Olsen, E.V., Christensen, L.B., Hviid, M., Ersboll, B.K. & Larsen, R. (2009). Virtual dissection of pig carcasses. Meat Science, 81, 699–704 Walstra, P. & Merkus, G. S. M. (1996). Procedure for assessment of the lean meat percentage as a consequence of the new EU reference dissection method in pig carcass classification: based on discussion in the EU Management Committee on Pig Meat and based on discussions with dissection experts during a meeting on May 18-19, 1994 at Zeist, NL (No. 96.014). ID-DLO.

A descriptive study of acute outbreaks of respiratory disease in Norwegian fattening pig herds

BackgroundRespiratory diseases are major health concerns in the pig production sector worldwide, contributing adversely to morbidity and mortality. Over the past years there was a rise in reported incidents of respiratory disease in pigs in Norway, despite population wide freedom from Aujeszky´s disease, porcine reproductive and respiratory syndrome, porcine respiratory corona virus and enzootic pneumonia. The main objective of this study was to investigate acute outbreaks of respiratory disease in conventional Norwegian fattening pig herds. The study included 14 herds. In seven herds with reported outbreaks of acute respiratory disease, data on clinical signs was recorded and samples for laboratory examination were collected. Diagnostic protocols were compared by parallel analysis of clinically healthy pigs from seven non-outbreak herds.ResultsThe most commonly reported clinical signs were sudden deaths and dyspnea. An average compartment morbidity of 60%, mortality of 4% and case fatality of 9% was recorded in the outbreak herds. Post-mortem examinations revealed acute lesions resembling porcine pleuropneumonia in all 28 pigs investigated from the outbreak herds and in 2 of the 24 (8%) pigs from the non-outbreak herds. Chronic lesions were recorded in another 2 pigs (8%) from the non-outbreak herds. Actinobacillus pleuropneumoniae serovar 8 was isolated from lungs and/or pleura from all tested pigs (n = 28) in the outbreak herds, and from 2 out of 24 pigs (8%) in the non-outbreak herds, one pig with an acute and another pig with a chronic infection. No other significant bacterial findings were made. Seroconversion to A. pleuropneumoniae antibodies was detectable in all outbreak herds analyzed and in six out of seven non-outbreak herds, but the risk ratio for seroconversion of individual pigs was higher (risk ratio 2.3 [1.50- 3.43 95% CI; P < 0.001]) in the outbreak herds. All herds tested positive for porcine circovirus type 2 and negative for influenza A viruses on oral fluid RT-qPCR.ConclusionThe main etiological pathogen found during acute outbreaks of respiratory disease was A. pleuropneumoniae serovar 8. All pigs from outbreak herds had typical lesions of acute porcine pleuropneumonia, and only A. pleuropneumoniae serovar 8 was identified. Co-infections were not found to impact disease development.

Dissemination of Quinolone-Resistant Escherichia coli in the Norwegian Broiler and Pig Production Chains and Possible Persistence in the Broiler Production Environment.

In Norway, the use of quinolones in livestock populations is very low, and prophylactic use is prohibited. Despite this, quinolone-resistant Escherichia coli (QREC) isolates are present at low levels in several animal species. The source of these QREC isolates is unknown. The aim of this study was to characterize and compare QREC isolates from different animal species to identify putative factors that may promote the occurrence of QREC. A total of 280 QREC isolates, from broilers, pigs, red foxes, and wild birds, were whole-genome sequenced and analyzed. Well-known chromosomal and plasmid-mediated resistance mechanisms were identified. In addition, mutations in marR, marA, and rpoB causing novel amino acid substitutions in their respective proteins were detected. Phylogenetic analyses were used to determine the relationships between the isolates. Quinolone resistance mechanism patterns appeared to follow sequence type groups. Similar QREC isolates with similar resistance mechanism patterns were detected from the samples, and further phylogenetic analysis indicated close evolutionary relationships between specific isolates from different sources. This suggests the dissemination of highly similar QREC isolates between animal species and also the persistence of QREC strains within the broiler production chain. This highlights the importance of both control measures at the top of the production chain as well as biosecurity measures to avoid the further dissemination and persistence of QREC in these environments.IMPORTANCE Since antimicrobial usage is low in Norwegian animal husbandry, Norway is an ideal country to study antimicrobial resistance in the absence of selective pressure from antimicrobial usage. In particular, the usage of quinolones is very low, which makes it possible to investigate the spread and development of quinolone resistance in natural environments. Comparison of quinolone-resistant E. coli (QREC) isolates from livestock and wild animals in light of this low quinolone usage provides new insights into the development and dissemination of QREC in both natural and production environments. With this information, preventive measures may be taken to prevent further dissemination within Norwegian livestock and between other animals, thus maintaining the favorable situation in Norway.

Antibodies of influenza A(H1N1)pdm09 virus in pigs' sera cross-react with other influenza A virus subtypes. A retrospective epidemiological interpretation of Norway's serosurveillance data from 2009-2017.

Since the incursion of influenza A(H1N1)pdm09 virus in 2009, serosurveillance every year of the Norwegian pig population revealed the herd prevalence for influenza A(H1N1)pdm09 (HIN1pdm09) has stabilised between 40% and 50%. Between 30 September 2009 and 14 September 2017, the Norwegian Veterinary Institute and Norwegian Food Safety Authority screened 35,551 pigs for antibodies to influenza A viruses (IAVs) from 8,636 herds and found 26% or 8,819 pigs' sera ELISA positive (titre ≥40). Subtyping these IAV antibodies from 8,214 pigs in 3,629 herds, by a routine haemagglutination inhibition test (HAIT) against four standard antigens produced 13,771 positive results (HAIT titre ≥40) of binding antibodies. The four antigen subtypes eliciting positive HAIT titre in descending frequencies were immunogen H1N1pdm09 (n = 8,200 or 99.8%), swine influenza A virus (SIVs) subtypes swH1N1 (n = 5,164 or 62%), swH1N2 (n = 395 or 5%) and swH3N2 (n = 12 or 0.1%). Of these 8,214 pig pigs sera, 3,039 produced homologous HAIT subtyping, almost exclusively immunogen H1N1pdm09 (n = 3,026 or 99.6%). Using HAIT titre of pig and herd geometric mean titre (GMT) as two continuous outcome variables, and with the data already structured hierarchically, we used mixed effects linear regression analysis to investigate the impact of predictors of interests had on the outcomes. For the full data, the predictors in the regression model include categorical predictors antigen subtype (H1N1pdm09, swH1N1, swH1N2 & swH3N2), and production type (sow herd or fattening herd), ordinal predictors year (longitudinally from 2009 to 2017) and number of antigens in heterologous reactions (1, 2, 3, 4) in the same pig serum. The last predictor, the proportion of HAIT positive (antigen specific) in tested pigs within the herd, was a continuous predictor, which served as a proxy for days post-infection (dpi) or humoral response time in the pig or herd. Regression analysis on individual pig HAIT titres showed that antigen as a predictor, the coefficient for immunogen H1N1pdm09 was at least fourfold higher (P < 0.001) than the three SIVs antigen subtypes, whose much lower coefficients were statistically no different between the three SIVs antigen subtypes. Correspondingly, for herd GMT, immunogen H1N1pdm09 was 28-40-fold higher than the three SIVs antigen subtypes. Excluding the HAIT data of the three SIVs antigen subtypes, regression analysis focusing only on immunogen H1N1pdm09 increased greatly the coefficients of the predictors in the models. Homologous reactions (99.6% H1N1pdm09) have lower HAIT titres while the likelihood of the number of antigens involved in HAIT heterologous reactions in a single pig serum increased with higher HAIT titres of immunogen H1N1pdm09. For predictor 'production', sows and sow herds had higher HAIT titres and GMT compared to fattening pigs and fattening herds respectively. Herds with 'higher proportion of pigs tested positive' also had higher HAIT titre in the pig and herd GMT.

A descriptive report of the selenium distribution in tissues from pigs with mulberry heart disease (MHD)

BackgroundMulberry Heart Disease (MHD) is a condition affecting mainly young pigs in excellent body condition. Feed efficient pigs showing high average daily gains are more likely to be affected. MHD has been described as a challenge in Norwegian pig production over the last decade despite abundant supplies of vitamin E, and selenium (Se) close to the upper limits set by the EU. From 2015 to 2017, samples from documented MHD field cases were collected and compared with controls regarding post mortem findings and Se concentrations in numerous internal and external organs were determined in order to characterize the Se distribution, and to identify any differences between MHD cases and controls.Case presentationEight MHD cases from commercial farms and a pet pig producer located in the South West and East of Norway, and three control animals originating from these farms were included in this study. MHD cases and controls were weaned pigs with an average bodyweight (BW) of 17 kg (range 9 to 46 kg BW), with the exception of one pet piglet (Mangalica, 6 kg BW) that had only received sow milk. Selenium was determined in samples from the cardiovascular, digestive, immune, endocrine, integumentary, muscular, respiratory and urinary systems using inductively coupled plasma mass spectrometry (QQQ ICP-MS). All pigs with MHD suffered sudden deaths. Control animals were euthanized without being bled prior to necropsy and sampling. Significantly different mean Se concentrations between MHD cases and controls were found in cardiac samples as well as almost all skeletal muscles (P < 0.05). Based on the samples from ten different muscles (except the cardiac samples), mean Se concentrations in MHD cases were 0.34 (0.01) mg/ kg DM compared with 0.65 (0.02) mg/ kg DM in control pigs (P < 0.0001). In cardiac samples, mean Se concentrations from MHD cases were 0.87 (0.02) mg/ kg DM vs. 1.12 (0.04) mg/ kg DM (P < 0.0001). Additionally, significantly lower Se concentrations compared with controls were found in the liver as well as the caecum, duodenum, gastric ventricle, jejunum, kidney, skin and thymus samples.ConclusionsBased on the present work, the current common practice regarding tissue analyses in MHD cases could be refined to include other organs than liver and heart. The evident differences in mean Se concentrations in 9 out of 10 samples from the muscular system, could make such samples relevant for complementary measurements of Se concentrations to help confirm the MHD diagnosis. We find it interesting that although our limited number of sampled pigs are different in terms of genetics, size and feeding regimes, the variation of Se concentrations in a given organ was low between MHD cases. Since this report includes a limited number of MHD cases and controls, our results should be corroborated by a controlled, larger study.

Livestock-Associated MRSA CC1 in Norway; Introduction to Pig Farms, Zoonotic Transmission, and Eradication.

Farm animals have been identified as an emerging reservoir for transmission of livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) to humans. The low incidence of MRSA in humans and farm animals in Norway has led to the implementation of a national strategy of surveillance and control of LA-MRSA aiming to prevent livestock becoming a domestic source of MRSA to humans. In 2015, MRSA clonal complex 1 spa-type t177 was identified in nine Norwegian pig herds in two neighboring counties. An outbreak investigation was undertaken, and measures of control through eradication were imposed. We performed a register-based cohort study including pig herds and MRSA-positive persons in Norway between 2008 and 2016 to investigate the livestock-association of MRSA CC1, the transmission of the outbreak strain to humans before and after control measures, and the effect of control measures imposed. Data from the Norwegian Surveillance System of Communicable Diseases were merged with data collected through outbreak investigations for LA-MRSA, the National Registry and the Norwegian Register for Health Personnel. Whole-genome sequencing was performed on isolates from livestock and humans identified through contact tracing, in addition to t177 and t127 isolates diagnosed in persons in the same counties. It is likely that a farm worker introduced MRSA CC1 to a sow farm, and further transmission to eight fattening pig farms through trade of live pigs confirmed the potential for livestock association of this MRSA type. The outbreak strain formed a distinct phylogenetic cluster which in addition to the pig farms included one sheep herd and five exposed persons. None of the investigated isolates from possible cases without direct contact to the MRSA positive farms were phylogenetically related to the outbreak strain. Moreover, isolates of t177 or t127 from healthcare and community-acquired cases were not closely related to the outbreak cluster. Eradication measures imposed were effective in eliminating MRSA t177 from the positive pig holdings, and the outbreak strain was not detected in the national pig population or in persons from these counties after control measures.

Gut microbiota profiling in Norwegian weaner pigs reveals potentially beneficial effects of a high-fiber rapeseed diet.

Rapeseed meal (RSM) is an alternative feed ingredient to soybean meal (SBM) in pig diets. However, knowledge on the effect of RSM on gut health, especially in relation to changes in gut microbiota is still limited. In our study, Norwegian Landrace weaner pigs were fed with either a control diet (CON) based on wheat, barley and SBM, or a high-fiber experimental diet where SBM was replaced by RSM (RSF). We found no large differences in the gut microbiota of pigs fed the two diets, suggesting that RSF does not disturb the gut microbiota and the normal gut function. The relative abundance of SCFA-producing phylotypes and colon-health related phylotypes increased in the large intestine of RSF-fed pigs. Among them, Lachnospira and Coprococcus were negatively associated with the presence of neutrophils in the colon wall. The higher abundance of these bacteria in colon of RSF pigs may suggest an anti-inflammatory stimulus effect of the RSF diet. The gut microbiota of RSF-fed pigs was relatively unaltered following episodes of diarrhea suggesting that the RSF diet may promote robustness in weaner pigs and reduce the risk of dysbiosis.

Abstract 326: The Prediction Value of Minute Volum of Carbon Dioxide (mvco2) for Return of Spontaneous Circulation in a Porcine Model of Cardiac Arrest

The prediction value of Minute Volum of Carbon dioxide (MVCO2) for return of spontaneous circulation in a porcine model of cardiac arrest Background: Parameters that can predict ROSC ramins incompletely understood. EtCO2 in prediction ROSC may be influenced by minute ventilation during CPR. Minute volume of CO2 (MVCO2) theoratically can be less affected by ventilation. The value of MVCO2 in prediction ROSC remains unknown. Objective: To investigate whether MVCO2 can predict the ROSC in porcine model and define the best cutoff value to predict failure of ROSC. Method: 15 healthy Norwegian domestic pigs received mechanical CPR 2 mins after electriclly induced VF. ETCO2, MVCO2, ALP, MAP, were recorded continuously. Arterial and central venous blood gas were tested at 5-minute after the start of resuscitation. Defbrillation was given at 6-mins after resuscitaion. Parameters were compared between animals with ROSC after difibrillation and those without. Results: 9 pigs were successfully resuscitated after defibrillation while 6 failed. There was no difference of MVCO2, ETCO2, ALP, and MAP between the two groups before induced VF. There was a correlation between MVCO2, ETCO2, ALP, and MAP values (Fig 1). Furthermore, MVCO2 was significantly lower among those animals that failed ROSC, the receiver operating characteristic (ROC) curve of MVCO2 predicte difibrillation results showed that the area under the ROC curve was 0.981. The optimal cut-off value was 123.5ml/min, with sensitivity of 97.2% and specificity of 91.7% (Fig 2). Multivariate logistic regression models suggested that MVCO2 index was an important factor affecting the prognosis of resuscitation. Summary and conclusion: This study indicates MVCO2 are highly related with ETCO2, ALP, and MAP with a better preidiction value for resuscitation prognosis than ETCO2, ALP, and MAP.

Haemodynamic outcomes during piston-based mechanical CPR with or without active decompression in a porcine model of cardiac arrest

BackgroundExperimental active compression-decompression (ACD) CPR is associated with increased haemodynamic outcomes compared to standard mechanical chest compressions. Since no clinically available mechanical chest compression device is capable of ACD-CPR, we modified the LUCAS 2 (Physio-Control, Lund, Sweden) to deliver ACD-CPR, hypothesising it would improve haemodynamic outcomes compared with standard LUCAS CPR on pigs with cardiac arrest.MethodsThe modified LUCAS delivering 5 cm compressions with or without 2 cm active decompression above anatomical chest level was studied in a randomized crossover design on 19 Norwegian domestic pigs. VF was electrically induced and untreated for 2 min. Each pig received ACD-CPR and standard mechanical CPR in three 180-s. phases. We measured aortic, right atrial, coronary perfusion, intracranial and oesophageal pressure, cerebral and carotid blood flow and cardiac output. Two-sided paired samples t-test was used for continuous parametric data and Wilcoxon test for non-parametric data. P < 0.05 was considered significant.ResultsDue to injuries/device failure, the experimental protocol was completed in nine of 19 pigs. Cardiac output (l/min, median, (25, 75-percentiles): 1.5 (1.1, 1.7) vs. 1.1 (0.8, 1.5), p < 0.01), cerebral blood flow (AU, 297 vs. 253, mean difference: 44, 95% CI; 14–74, p = 0.01), and carotid blood flow (l/min, median, (25, 75-percentiles): 97 (70, 106) vs. 83 (57, 94), p < 0.01) were higher during ACD-CPR compared to standard mechanical CPR. Coronary perfusion pressure (CPP) trended towards higher in end decompression phase.ConclusionCardiac output and brain blood flow improved with mechanical ACD-CPR and CPP trended towards higher during end-diastole compared to standard LUCAS CPR.

Fine mapping of a QTL affecting levels of skatole on pig chromosome 7

BackgroundPrevious studies in the Norwegian pig breeds Landrace and Duroc have revealed a QTL for levels of skatole located in the region 74.7–80.5 Mb on SSC7. Skatole is one of the main components causing boar taint, which gives an undesirable smell and taste to the pig meat when heated. Surgical castration of boars is a common practice to reduce the risk of boar taint, however, a selection for boars genetically predisposed for low levels of taint would help eliminating the need for castration and be advantageous for both economic and welfare reasons. In order to identify the causal mutation(s) for the QTL and/or identify genetic markers for selection purposes we performed a fine mapping of the SSC7 skatole QTL region.ResultsA dense set of markers on SSC7 was obtained by whole genome re-sequencing of 24 Norwegian Landrace and 23 Duroc boars. Subsets of 126 and 157 SNPs were used for association analyses in Landrace and Duroc, respectively. Significant single markers associated with skatole spanned a large 4.4 Mb region from 75.9–80.3 Mb in Landrace, with the highest test scores found in a region between the genes NOVA1 and TGM1 (p < 0.001). The same QTL was obtained in Duroc and, although less significant, with associated SNPs spanning a 1.2 Mb region from 78.9–80.1 Mb (p < 0.01). The highest test scores in Duroc were found in genes of the granzyme family (GZMB and GZMH-like) and STXBP6. Haplotypes associated with levels of skatole were identified in Landrace but not in Duroc, and a haplotype block was found to explain 2.3% of the phenotypic variation for skatole. The SNPs in this region were not associated with levels of sex steroids.ConclusionsFine mapping of a QTL for skatole on SSC7 confirmed associations of this region with skatole levels in pigs. The QTL region was narrowed down to 4.4 Mb in Landrace and haplotypes explaining 2.3% of the phenotypic variance for skatole levels were identified. Results confirmed that sex steroids are not affected by this QTL region, making these markers attractive for selection against boar taint.

Occurrence and spread of influenza A(H1N1)pdm09 virus infection in Norwegian pig herds based on active serosurveillance from 2010 to 2014.

The incursion of influenza A(H1N1)pdm09 virus was detected by Norway's active serosurveillance of its pig population in 2009. Since then, surveillance data from 2010 to 2014 revealed that 54% of 5643 herd tests involving 1567 pig herds and 28% of 23 036 blood samples screened positive for antibodies against influenza A virus. Positive herds were confirmed to have influenza A(H1N1)pdm09 virus infection by haemagglutination inhibition test. In 50% of positive herd tests, ⩾60% of the sampled pigs in each herd had antibodies against influenza A(H1N1)pdm09 virus. This within-herd animal seroprevalence did not vary for type of production, herd size or year of test. The overall running mean of national herd seroprevalence, and annual herd incidence risks fluctuated narrowly around the means of 45% and 32%, respectively, with the highest levels recorded in the three densest pig-producing counties. The probability of a herd being seropositive varied in the five production classes, which were sow pools, multiplier herds, conventional sow herds, nucleus herds, and fattening herds in descending order of likelihood. Large herds were more likely to be seropositive. Seropositive herds were highly likely to be seropositive the following year. The study shows that influenza A(H1N1)pdm09 virus is established in the Norwegian pig population with recurrent and new herd infections every year with the national herd seroprevalence in 2014 hovering at around 43% (95% confidence interval 40-46%).

Production impact of influenza A(H1N1)pdm09 virus infection on fattening pigs in Norway.

Newly emerged influenza A(H1N1)pdm09 virus infection in Norwegian pigs, although often observed in a subclinical form, can lower the pig's growth performance by reducing feed efficiency in terms of a poorer feed conversion ratio. Infected pigs would consume more feed and require protracted production time to reach market weight. In our observational longitudinal study, growth performance data from 728 control pigs and 193 infected pigs with known viral shedding time points were analyzed using mixed linear regression models to give estimates of the marginal effects of infection. Gaussian curves describing the variability of the estimates at the individual pig level formed the fundamental inputs to our stochastic models. The models were constructed to simulate the summed negative effects of the infection at the batch level of 150 fattening pigs growing from 33 to 100 kg. Other inputs of variability and uncertainty were 1) batch transmission points, 2) pig infection points to reflect the disease transmission dynamics of the virus, and 3) final prevalence of infected pigs in the batch. Monte Carlo random sampling gave 5,000 estimates on the outputs of the marginal effects for each pig. These results were summed up to provide estimates for a batch size of 150 pigs. This figure was adjusted by our final prevalence distribution function, which was also derived from the longitudinal study with 12 cohorts of infected pigs. For a 150-fattening-pig herd randomly selected from the population, the marginal effects of the infection were 1) 835 kg (fifth percentile) to 1,350 kg (95th percentile) increased feed intake and 2) 194 (fifth percentile) to 334 (95th percentile) pig days in excess of expected figures for an uninfected batch. A batch infected during growth phase 3 (81 to 100 kg BW) gave the worst results since the longitudinal study showed that a pig infected during growth phase 3 required more feed and a greater protracted production time compared to younger infected pigs. Sensitivity analysis showed that final prevalence had the greatest impact on the conditional mean and variation of the marginal effects of infections. Batch transmission point was the next most influential factor. Lowering the final prevalence and preventing older fattening pigs from being infected will have the greatest benefit in saving feed cost and reducing delay in getting the pigs to the market.

Prediction precision for lean meat percentage in Norwegian pig carcasses using ‘Hennessy grading probe 7’: Evaluation of methods emphasized at exploiting additional information from computed tomography

ABSTRACTThe present study aims at improving the prediction of lean meat percentage (LMP) for pig carcasses based on on-line measurements from the slaughterhouses using the ‘Hennessy Grading Probe 7’ (HGP7) and auxiliary information such as gender and breed. The prediction performance is evaluated using an empirical Bayes method capable of utilizing information from a surrogate variable, that is, LMP from computed tomography. HGP7 measures thicknesses of fat and meat layers. The HGP7 measurements of subcutaneous fat, sirloin height and interior fat layer should be included as predictor variables together with gender. For efficiency at the slaughter-line gender might be omitted. The empirical Bayes method improved prediction precision only marginally compared with the standard ordinary least-squares method when applied to the full set of data. However, simulations show that the empirical Bayes method enables a considerable reduction of the data sample size without appreciable loss of prediction precision.

On the use of the transmission disequilibrium test to detect pseudo-autosomal variants affecting traits with sex-limited expression

We herein describe the realization of a genome-wide association study for scrotal hernia and cryptorchidism in Norwegian and Belgian commercial pig populations. We have used the transmission disequilibrium test to avoid spurious associations due to population stratification. By doing so, we obtained genome-wide significant signals for both diseases with SNPs located in the pseudo-autosomal region in the vicinity of the pseudo-autosomal boundary. By further analyzing these signals, we demonstrate that the observed transmission disequilibria are artifactual. We determine that transmission bias at pseudo-autosomal markers will occur (i) when analyzing traits with sex-limited expression and (ii) when the allelic frequencies at the marker locus differ between X and Y chromosomes. We show that the bias is due to the fact that (i) sires will preferentially transmit the allele enriched on the Y (respectively X) chromosome to affected sons (respectively daughters) and (ii) dams will appear to preferentially transmit the allele enriched on the Y (respectively X) to affected sons (respectively daughters), as offspring inheriting the other allele are more likely to be non-informative. We define the conditions to mitigate these issues, namely by (i) extracting information from maternal meiosis only and (ii) ignoring trios for which sire and dam have the same heterozygous genotype. We show that by applying these rules to scrotal hernia and cryptorchidism, the pseudo-autosomal signals disappear, confirming their spurious nature.