Assessment of temperature and time on the survivability of porcine reproductive and respiratory syndrome virus (PRRSV) and porcine epidemic diarrhea virus (PEDV) on experimentally contaminated surfaces

Fomites might be responsible for virus introduction in swine farms, highlighting the importance of implementing practices to minimize the probability of virus introduction. The study’s objective was to assess the efficacy of different combinations of temperatures and holding-times on detecting live PRRSV and PEDV on surfaces commonly found in supply entry rooms in swine farms. Two PRRSV isolates (MN 184 and 1-4-4 L1C variant) and one PEDV isolate (NC 49469/2013) were inoculated on cardboard and aluminum. An experimental study tested combinations of four temperatures (20°C, 30°C, 40°C, and 50°C) and six holding-times (15 minutes, 60 minutes, 6 hours, 12 hours, 24 hours, and 36 hours) for the presence of the viruses on each surface type. After virus titration, virus presence was assessed by assessing the cytopathic effects and immunofluorescence staining. The titers were expressed as log10 TCID50/ml, and regression models; half-lives equations were calculated to assess differences between treatments and time to not detect the live virus. The results suggest that the minimum time that surfaces should be held to not detect the virus at 30°C was 24 hours, 40°C required 12 hours, and 50°C required 6 hours; aluminum surfaces took longer to reach the desired temperature compared to cardboard. The results suggest that PRRSV 1-4-4 L1C variant had higher half-lives at higher temperatures than PRRSV MN 184. In conclusion, time and temperature combinations effectively decrease the concentration of PRRSV and PEDV on different surfaces found in supply entry rooms in swine farms.This article is published as Mil-Homens, Mafalda, Ethan Aljets, Rodrigo C. Paiva, Isadora Machado, Guilherme Cezar, Onyekachukwu Osemeke, Daniel Moraes et al. "Assessment of temperature and time on the survivability of porcine reproductive and respiratory syndrome virus (PRRSV) and porcine epidemic diarrhea virus (PEDV) on experimentally contaminated surfaces." Plos one 19, no. 1 (2024): e0291181. doi: https://doi.org/10.1371/journal.pone.0291181. © 2024 Mil-Homens et al. This is an open access article distributed under the terms of the Creative Commons Attribution License

Caracterização do gênero, da raça e da idade de uma população de 7.780 cães da Região Central do Rio Grande do Sul submetidos à necropsia ao longo de cinco décadas (1964-2013)

RESUMO: Devido à ausência de um banco de dados demográficos da população canina que habita a Região Central do Rio Grande do Sul (RS) e à necessidade em se estabelecer uma “população controle” para a melhor interpretação da prevalência das doenças diagnosticadas pelo Laboratório de Patologia Veterinária (LPV-UFSM) da Universidade Federal de Santa Maria (UFSM), este estudo objetivou realizar uma análise das características relacionadas à raça, ao gênero e à idade dos cães necropsiados neste serviço de diagnóstico ao longo de 50 anos (1964-2013). Para isto, os laudos de necropsias de cães, realizadas entre 1964 e 2013, foram revisados, e deles foram retiradas informações referentes ao gênero, à idade e às raças de todos os cães oriundos dos municípios que compõem a Região Central do RS. Ao todo, 7.780 cães foram necropsiados; desses, 469 (6%) na primeira década (1964-1973), 1.133 (14,6%) na segunda década (1974-1983), 1.334 (17,1%) na terceira década (1984-1993), 1.705 (22%) na quarta década (1994-2003) e 3.139 (40,3%) na quinta década (2004-2013). Do total de cães com gênero informado nos laudos, 52,6% eram machos e 47,4% eram fêmeas. A mediana da idade de morte foi de três anos. Dos cães cuja raça foi informada nos laudos, 59,8% eram de raça definida (RD) e 40,2% não tinham raça definida (SRD). As raças de porte grande ou gigante mais frequentes foram: Pastor Alemão (17,2%), Boxer (6,9%), Rottweiler (5,3%), Fila Brasileiro (4,6%), Pointer Inglês (3,9%), Collie Pelo Longo (3,7%) Dobermann (3,7%) e Labrador Retriever (2,1%). As raças de porte pequeno ou médio mais frequentes foram: Poodle (8,9%), Dachshund (6,3%), Pinscher Miniatura (5,6%), Cocker Spaniel Inglês (4,5%), Pequinês (3,4%), Yorkshire Terrier (3,3%) e Terrier Brasileiro (2,8%). Houve um aumento na proporção de fêmeas e um crescimento na mediana referente à idade de morte ao longo das cinco décadas avaliadas. Apesar de não ter havido um aumento relevante na proporção de cães de RD em comparação com os SRD, observaram-se algumas mudanças na ocorrência de diferentes raças ao longo do tempo, incluindo principalmente uma dramática diminuição na percentagem de Pequinês, Terrier Brasileiro, Pointer Inglês e Pastor Alemão, e um aumento marcado na percentagem de Poodle, Dachshund, Rottweiler e Labrador Retriever. Os resultados aqui apresentados servirão como um subsídio comparativo para futuros estudos retrospectivos sobre prevalência de doenças em cães da Região Central do RS, auxiliando para uma mais correta compreensão e interpretação dos resultados encontrados nesses levantamentos de dados

Ovinocultura do Rio Grande do Sul: descrição do sistema produtivo e dos principais aspectos sanitários e reprodutivos

A ovinocultura sempre foi uma atividade de grande importância econômica e de tradição para o Estado do Rio Grande do Sul (RS), mesmo com as crises da lã ocorridas nas décadas de 80 e 90, o rebanho ovino Gaúcho continua sendo o maior a nível nacional. Com a escassez de dados sobre essa atividade, o presente estudo possui como objetivo caracterizar a ovinocultura do RS. Para isso, foi utilizada uma amostragem planejada, caracterizada pela aleatoriedade e estratificação da amostra pelas sete Mesorregiões do Estado. Foram analisadas 705 propriedades rurais através de um questionário epidemiológico, aplicado por 25 veterinários do Departamento de Defesa Animal, da Secretaria da Agricultura, Pecuária e Agronegócio do Estado do Rio Grande do Sul. Conforme os resultados obtidos, a ovinocultura gaúcha é explorada extensivamente e baseada na produção conjunta de carne e lã, cuja principal finalidade é a subsistência. Assim, demonstrando que essa atividade ainda mantém padrões de sua origem, com pouca tecnificação, tanto em aspectos sanitários quanto reprodutivos, revelando, portanto, que a ovinocultura gaúcha ainda é vista como uma produção secundária pelos produtores rurais gaúchos, o que pode ser explicado pelos baixos investimentos neste setor

Cough associated with the detection of Mycoplasma hyopneumoniae DNA in clinical and environmental specimens under controlled conditions

Background: The association of cough with Mycoplasma hyopneumoniae (MHP) DNA detection in specimens was evaluated under conditions in which the MHP status of inoculated and contact-infected pen mates was closely monitored for 59 days post-inoculation (DPI). Methods: Seven-week-old pigs (n = 39) were allocated to five rooms (with one pen). Rooms contained 9 pigs each, with 1, 3, 6, or 9 MHP-inoculated pigs, respectively, except Room 5 (three sham-inoculated pigs). Cough data (2 × week) and specimens, tracheal swabs (2 × week), oral fluids (daily), drinker wipes (~ 1 × week), and air samples (3 × week) were collected. At 59 DPI, pigs were euthanized, and lung and trachea were evaluated for gross and microscopic lesions. Predictive cough value to MHP DNA detection in drinker and oral fluid samples were estimated using mixed logistic regression. Results: Following inoculation, MHP DNA was first detected in tracheal swabs from inoculated pigs (DPI 3), then oral fluids (DPI 8), air samples (DPI 10), and drinker wipes (21 DPI). MHP DNA was detected in oral fluids in 17 of 59 (Room 1) to 43 of 59 (Room 3) samples, drinker wipes in 4 of 8 (Rooms 2 and 3) to 5 of 8 (Rooms 1 and 4) samples, and air samples in 5 of 26 (Room 2) or 3 of 26 (Room 4) samples. Logistic regression showed that the frequency of coughing pigs in a pen was associated with the probability of MHP DNA detection in oral fluids (P < 0.01) and nearly associated with drinker wipes (P = 0.08). Pathology data revealed an association between the period when infection was first detected and the severity of gross lung lesions. Conclusions: Dry, non-productive coughs suggest the presence of MHP, but laboratory testing and MHP DNA detection is required for confirmation. Based on the data from this study, oral fluids and drinker wipes may provide a convenient alternative for MHP DNA detection at the pen level when cough is present. This information may help practitioners in specimen selection for MHP surveillance.This article is published as Silva, Ana Paula S. Poeta, Gabriel Y. Storino, Franco S. Matias Ferreyra, Min Zhang, Eduardo Fano, Dale Polson, Chong Wang et al. "Cough associated with the detection of Mycoplasma hyopneumoniae DNA in clinical and environmental specimens under controlled conditions." Porcine Health Management 8, no. 1 (2022): 1-13. DOI: 10.1186/s40813-022-00249-y. Copyright 2022 The Author(s). Attribution 4.0 International (CC BY 4.0). Posted with permission

Molecular characterization of Glaesserella parasuis strains circulating in North American swine production systems

Abstract Background Glaesserella parasuis is the causative agent of Glässer’s disease in pigs. Serotyping is the most common method used to type G. parasuis isolates. However, the high number of non-typables (NT) and low discriminatory power make serotyping problematic. In this study, 218 field clinical isolates and 15 G. parasuis reference strains were whole-genome sequenced (WGS). Multilocus sequence types (MLST), serotypes, core-genome phylogeny, antimicrobial resistance (AMR) genes, and putative virulence gene information was extracted. Results In silico WGS serotyping identified 11 of 15 serotypes. The most frequently detected serotypes were 7, 13, 4, and 2. MLST identified 72 sequence types (STs), of which 66 were novel. The most predominant ST was ST454. Core-genome phylogeny depicted 3 primary lineages (LI, LII, and LIII), with LIIIA sublineage isolates lacking all vtaA genes, based on the structure of the phylogenetic tree and the number of virulence genes. At least one group 1 vtaA virulence genes were observed in most isolates (97.2%), except for serotype 8 (ST299 and ST406), 15 (ST408 and ST552) and NT (ST448). A few group 1 vtaA genes were significantly associated with certain serotypes or STs. The putative virulence gene lsgB, was detected in 8.3% of the isolates which were predominantly of serotype 5/12. While most isolates carried the bcr, ksgA, and bacA genes, the following antimicrobial resistant genes were detected in lower frequency;  blaZ (6.9%), tetM (3.7%), spc (3.7%), tetB (2.8%), bla-ROB-1 (1.8%), ermA (1.8%), strA (1.4%), qnrB (0.5%), and aph3''Ia (0.5%).   Conclusion This study showed the use of WGS to type G. parasuis isolates and can be considered an alternative to the more labor-intensive and traditional serotyping and standard MLST. Core-genome phylogeny provided the best strain discrimination. These findings will lead to a better understanding of the molecular epidemiology and virulence in G. parasuis that can be applied to the future development of diagnostic tools, autogenous vaccines, evaluation of antibiotic use, prevention, and disease control

Molecular characterization of Glaesserella parasuis strains circulating in North American swine production systems

Acknowledgements: We acknowledge the Iowa State University Veterinary Diagnostic Laboratory Bacteriology section for their invaluable work carrying out the bacteriological culture of all study isolates. We thank the veterinarians and swine production systems for the sharing of isolates.Background: Glaesserella parasuis is the causative agent of Glässer’s disease in pigs. Serotyping is the most common method used to type G. parasuis isolates. However, the high number of non-typables (NT) and low discriminatory power make serotyping problematic. In this study, 218 field clinical isolates and 15 G. parasuis reference strains were whole-genome sequenced (WGS). Multilocus sequence types (MLST), serotypes, core-genome phylogeny, antimicrobial resistance (AMR) genes, and putative virulence gene information was extracted. Results: In silico WGS serotyping identified 11 of 15 serotypes. The most frequently detected serotypes were 7, 13, 4, and 2. MLST identified 72 sequence types (STs), of which 66 were novel. The most predominant ST was ST454. Core-genome phylogeny depicted 3 primary lineages (LI, LII, and LIII), with LIIIA sublineage isolates lacking all vtaA genes, based on the structure of the phylogenetic tree and the number of virulence genes. At least one group 1 vtaA virulence genes were observed in most isolates (97.2%), except for serotype 8 (ST299 and ST406), 15 (ST408 and ST552) and NT (ST448). A few group 1 vtaA genes were significantly associated with certain serotypes or STs. The putative virulence gene lsgB, was detected in 8.3% of the isolates which were predominantly of serotype 5/12. While most isolates carried the bcr, ksgA, and bacA genes, the following antimicrobial resistant genes were detected in lower frequency; blaZ (6.9%), tetM (3.7%), spc (3.7%), tetB (2.8%), bla-ROB-1 (1.8%), ermA (1.8%), strA (1.4%), qnrB (0.5%), and aph3''Ia (0.5%). Conclusion: This study showed the use of WGS to type G. parasuis isolates and can be considered an alternative to the more labor-intensive and traditional serotyping and standard MLST. Core-genome phylogeny provided the best strain discrimination. These findings will lead to a better understanding of the molecular epidemiology and virulence in G. parasuis that can be applied to the future development of diagnostic tools, autogenous vaccines, evaluation of antibiotic use, prevention, and disease control

Molecular characterization of Glaesserella parasuis strains circulating in North American swine production systems.

Acknowledgements: We acknowledge the Iowa State University Veterinary Diagnostic Laboratory Bacteriology section for their invaluable work carrying out the bacteriological culture of all study isolates. We thank the veterinarians and swine production systems for the sharing of isolates.BACKGROUND: Glaesserella parasuis is the causative agent of Glässer's disease in pigs. Serotyping is the most common method used to type G. parasuis isolates. However, the high number of non-typables (NT) and low discriminatory power make serotyping problematic. In this study, 218 field clinical isolates and 15 G. parasuis reference strains were whole-genome sequenced (WGS). Multilocus sequence types (MLST), serotypes, core-genome phylogeny, antimicrobial resistance (AMR) genes, and putative virulence gene information was extracted. RESULTS: In silico WGS serotyping identified 11 of 15 serotypes. The most frequently detected serotypes were 7, 13, 4, and 2. MLST identified 72 sequence types (STs), of which 66 were novel. The most predominant ST was ST454. Core-genome phylogeny depicted 3 primary lineages (LI, LII, and LIII), with LIIIA sublineage isolates lacking all vtaA genes, based on the structure of the phylogenetic tree and the number of virulence genes. At least one group 1 vtaA virulence genes were observed in most isolates (97.2%), except for serotype 8 (ST299 and ST406), 15 (ST408 and ST552) and NT (ST448). A few group 1 vtaA genes were significantly associated with certain serotypes or STs. The putative virulence gene lsgB, was detected in 8.3% of the isolates which were predominantly of serotype 5/12. While most isolates carried the bcr, ksgA, and bacA genes, the following antimicrobial resistant genes were detected in lower frequency;  blaZ (6.9%), tetM (3.7%), spc (3.7%), tetB (2.8%), bla-ROB-1 (1.8%), ermA (1.8%), strA (1.4%), qnrB (0.5%), and aph3''Ia (0.5%).   CONCLUSION: This study showed the use of WGS to type G. parasuis isolates and can be considered an alternative to the more labor-intensive and traditional serotyping and standard MLST. Core-genome phylogeny provided the best strain discrimination. These findings will lead to a better understanding of the molecular epidemiology and virulence in G. parasuis that can be applied to the future development of diagnostic tools, autogenous vaccines, evaluation of antibiotic use, prevention, and disease control

Porcine reproductive and respiratory syndrome virus RNA detection in tongue tips from dead animals

The control of porcine reproductive and respiratory syndrome virus (PRRSV) hinges on monitoring and surveillance. The objective of this study was to assess PRRSV RNA detection by RT-PCR in tongue tips from dead suckling piglets compared to serum samples, processing fluids, and family oral fluids. Tongue tips and serum samples were collected from three PRRSV-positive breeding herd farms (farms A, B, and C) of three different age groups: newborns (<24h), processing (2 to 7 days of age), and weaning (18 to 22 days of age). Additionally, processing fluids and family oral fluids were collected from 2-7 days of age and weaning age respectively. In farms A and B, PRRSV RNA was detected in tongue tips from all age groups (100% and 95%, respectively). In addition, PRRSV RNA was detected in pooled serum samples (42% and 27%), processing fluids (100% and 50%), and family oral fluids (11% and 22%). Interestingly, the average Ct value from tongue tips was numerically lower than the average Ct value from serum samples in the newborn age. In farm C, PRRSV RNA was only detected in serum samples (60%) and family oral fluids (43%), both from the weaning age. Further, no PRRSV RNA was detected in tongue tips when pooled serum samples from the same age group tested PRRSV RNA-negative. Taken together, these results demonstrate the potential value of tongue tips for PRRSV monitoring and surveillance.This is a pre-print of the article Isadora F. Machado, Edison S. Magalhães, Ana Paula S. Poeta Silva, et al. Porcine reproductive and respiratory syndrome virus RNA detection in tongue tips from dead animals. Authorea. June 24, 2022. DOI: 10.22541/au.165609902.27121343/v1. Copyright 2022 The Authors. Posted with permission