PMID- 37635762 OWN - NLM STAT- PubMed-not-MEDLINE LR - 20230829 IS - 2297-1769 (Print) IS - 2297-1769 (Electronic) IS - 2297-1769 (Linking) VI - 10 DP - 2023 TI - A cross-sectional assessment of PRRSV nucleic acid detection by RT-qPCR in serum, ear-vein blood swabs, nasal swabs, and oral swabs from weaning-age pigs under field conditions. PG - 1200376 LID - 10.3389/fvets.2023.1200376 [doi] LID - 1200376 AB - INTRODUCTION: The porcine reproductive and respiratory syndrome virus (PRRSV) continues to challenge swine production in the US and most parts of the world. Effective PRRSV surveillance in swine herds can be challenging, especially because the virus can persist and sustain a very low prevalence. Although weaning-age pigs are a strategic subpopulation in the surveillance of PRRSV in breeding herds, very few sample types have been validated and characterized for surveillance of this subpopulation. The objectives of this study, therefore, were to compare PRRSV RNA detection rates in serum, oral swabs (OS), nasal swabs (NS), ear-vein blood swabs (ES), and family oral fluids (FOF) obtained from weaning-age pigs and to assess the effect of litter-level pooling on the reverse transcription-quantitative polymerase chain reaction (RT-qPCR) detection of PRRSV RNA. METHODS: Three eligible PRRSV-positive herds in the Midwestern USA were selected for this study. 666 pigs across 55 litters were sampled for serum, NS, ES, OS, and FOF. RT-qPCR tests were done on these samples individually and on the litter-level pools of the swabs. Litter-level pools of each swab sample type were made by combining equal volumes of each swab taken from the pigs within a litter. RESULTS: Ninety-six piglets distributed across 22 litters were positive by PRRSV RT-qPCR on serum, 80 piglets distributed across 15 litters were positive on ES, 80 piglets distributed across 17 litters were positive on OS, and 72 piglets distributed across 14 litters were positive on NS. Cohen's kappa analyses showed near-perfect agreement between all paired ES, OS, NS, and serum comparisons (). The serum RT-qPCR cycle threshold values (Ct) strongly predicted PRRSV detection in swab samples. There was a >/= 95% probability of PRRSV detection in ES-, OS-, and NS pools when the proportion of positive swab samples was >/= 23%, >/= 27%, and >/= 26%, respectively. DISCUSSION: ES, NS, and OS can be used as surveillance samples for detecting PRRSV RNA by RT-qPCR in weaning-age pigs. The minimum number of piglets to be sampled by serum, ES, OS, and NS to be 95% confident of detecting >/= 1 infected piglet when PRRSV prevalence is >/= 10% is 30, 36, 36, and 40, respectively. CI - Copyright (c) 2023 Osemeke, Cezar, Paiva, Moraes, Machado, Magalhaes, Poeta Silva, Mil-Homens, Peng, Jayaraman, Trevisan, Silva, Gauger and Linhares. FAU - Osemeke, Onyekachukwu H AU - Osemeke OH AD - Fieldepi, Iowa State University College of Veterinary Medicine, Ames, IA, United States. FAU - Cezar, Guilherme A AU - Cezar GA AD - Fieldepi, Iowa State University College of Veterinary Medicine, Ames, IA, United States. FAU - Paiva, Rodrigo C AU - Paiva RC AD - Fieldepi, Iowa State University College of Veterinary Medicine, Ames, IA, United States. FAU - Moraes, Daniel C A AU - Moraes DCA AD - Fieldepi, Iowa State University College of Veterinary Medicine, Ames, IA, United States. FAU - Machado, Isadora F AU - Machado IF AD - Fieldepi, Iowa State University College of Veterinary Medicine, Ames, IA, United States. FAU - Magalhaes, Edison S AU - Magalhaes ES AD - Fieldepi, Iowa State University College of Veterinary Medicine, Ames, IA, United States. FAU - Poeta Silva, Ana Paula S AU - Poeta Silva APS AD - Fieldepi, Iowa State University College of Veterinary Medicine, Ames, IA, United States. FAU - Mil-Homens, Mafalda AU - Mil-Homens M AD - Fieldepi, Iowa State University College of Veterinary Medicine, Ames, IA, United States. FAU - Peng, Li AU - Peng L AD - Fieldepi, Iowa State University College of Veterinary Medicine, Ames, IA, United States. FAU - Jayaraman, Swaminathan AU - Jayaraman S AD - Fieldepi, Iowa State University College of Veterinary Medicine, Ames, IA, United States. FAU - Trevisan, Giovani AU - Trevisan G AD - Fieldepi, Iowa State University College of Veterinary Medicine, Ames, IA, United States. FAU - Silva, Gustavo S AU - Silva GS AD - Fieldepi, Iowa State University College of Veterinary Medicine, Ames, IA, United States. FAU - Gauger, Phillip C AU - Gauger PC AD - Veterinary Diagnostic and Production Animal Medicine Department of the College of Veterinary Medicine, Iowa State University, Ames, IA, United States. FAU - Linhares, Daniel C L AU - Linhares DCL AD - Fieldepi, Iowa State University College of Veterinary Medicine, Ames, IA, United States. LA - eng PT - Journal Article DEP - 20230810 PL - Switzerland TA - Front Vet Sci JT - Frontiers in veterinary science JID - 101666658 PMC - PMC10449646 OTO - NOTNLM OT - PRRSV OT - RT-qPCR OT - pool OT - serum OT - surveillance OT - swab OT - swine OT - weaning COIS- The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. EDAT- 2023/08/28 06:42 MHDA- 2023/08/28 06:43 PMCR- 2023/01/01 CRDT- 2023/08/28 04:25 PHST- 2023/04/04 00:00 [received] PHST- 2023/07/10 00:00 [accepted] PHST- 2023/08/28 06:43 [medline] PHST- 2023/08/28 06:42 [pubmed] PHST- 2023/08/28 04:25 [entrez] PHST- 2023/01/01 00:00 [pmc-release] AID - 10.3389/fvets.2023.1200376 [doi] PST - epublish SO - Front Vet Sci. 2023 Aug 10;10:1200376. doi: 10.3389/fvets.2023.1200376. eCollection 2023.