{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,2]],"date-time":"2026-06-02T05:57:21Z","timestamp":1780379841718,"version":"3.54.1"},"reference-count":33,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2025,4,29]],"date-time":"2025-04-29T00:00:00Z","timestamp":1745884800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Key R&amp;D plan project of Ningxia Autonomous Region","award":["2024BBF02021"],"award-info":[{"award-number":["2024BBF02021"]}]},{"name":"Key R&amp;D plan project of Ningxia Autonomous Region","award":["CARS-38-04B"],"award-info":[{"award-number":["CARS-38-04B"]}]},{"name":"Key R&amp;D plan project of Ningxia Autonomous Region","award":["GSAU-JSFW-2023-07"],"award-info":[{"award-number":["GSAU-JSFW-2023-07"]}]},{"name":"Key R&amp;D plan project of Ningxia Autonomous Region","award":["GSAU-JSFW-2023-08"],"award-info":[{"award-number":["GSAU-JSFW-2023-08"]}]},{"name":"the Technical System of Meat Sheep Industry","award":["2024BBF02021"],"award-info":[{"award-number":["2024BBF02021"]}]},{"name":"the Technical System of Meat Sheep Industry","award":["CARS-38-04B"],"award-info":[{"award-number":["CARS-38-04B"]}]},{"name":"the Technical System of Meat Sheep Industry","award":["GSAU-JSFW-2023-07"],"award-info":[{"award-number":["GSAU-JSFW-2023-07"]}]},{"name":"the Technical System of Meat Sheep Industry","award":["GSAU-JSFW-2023-08"],"award-info":[{"award-number":["GSAU-JSFW-2023-08"]}]},{"name":"the Animal Clinical Practice Project of Gansu Agricultural University","award":["2024BBF02021"],"award-info":[{"award-number":["2024BBF02021"]}]},{"name":"the Animal Clinical Practice Project of Gansu Agricultural University","award":["CARS-38-04B"],"award-info":[{"award-number":["CARS-38-04B"]}]},{"name":"the Animal Clinical Practice Project of Gansu Agricultural University","award":["GSAU-JSFW-2023-07"],"award-info":[{"award-number":["GSAU-JSFW-2023-07"]}]},{"name":"the Animal Clinical Practice Project of Gansu Agricultural University","award":["GSAU-JSFW-2023-08"],"award-info":[{"award-number":["GSAU-JSFW-2023-08"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Genes"],"abstract":"<jats:p>Background: In recent years, enzootic nasal tumor virus 2 (ENTV-2) has become prevalent in China, resulting in substantial economic losses for the goat industry. In order to enrich the availability of detection methods for ENTV-2, this study developed an expedited and accurate reverse-transcription quantitative real-time polymerase chain reaction (RT-qPCR) assay to facilitate the detection and quantification of ENTV-2. Methods: Specifically, a pair of primers and a TaqMan probe targeting conserved regions of the pro gene were designed to allow the specific amplification and detection of viral RNA in clinical samples. Moreover, modifying the method for use in a quantitative real-time PCR (qPCR) assay enables the detection of proviral DNA in tumor specimens. Results: Both methods exhibited a detection limit for the ENTV-2 standard plasmid at 100 copies\/\u00b5L. The detection methods we established exhibited high specificity and sensitivity to ENTV-2, without cross-reactivity with other pathogens causing respiratory diseases or endogenous retroviruses (EBRVs). We performed an ENTV-2 analysis of clinical samples in goats via RT-qPCR using nasal swab samples (n = 558) collected from three geographically distinct flocks in Lingyou County, Baoji City, Shaanxi Province, China, and 58 positive samples were detected for a positivity rate of 10.4%. After euthanasia, the autopsy report showed nasal cavity masses. Histopathological analysis demonstrated an epithelial neoplasm, in compliance with the features of enzootic nasal adenocarcinoma (ENA). Three full-length genomes were sequenced to assess genomic sequence conservation and variation. Multiple-sequence alignment demonstrated the existence of sequence variations among strains. Phylogenetic analysis of the nucleotide sequences revealed that the ENTV-2 SX1~3 isolates were phylogenetically related to the Chinese ENTV-2 isolates, especially the JY strain. Furthermore, recombination analysis suggested that both ENTV-2 SX1 and ENTV-2 SX2 might be recombinant variants. Conclusions: In conclusion, both methods are highly specific for the pro gene of ENTV-2, and the development of this assay has been deemed crucial to the early identification and subsequent control of this viral infection. Our results provide valuable information for further research on the genetic variation and evolution of ENTV-2 in China.<\/jats:p>","DOI":"10.3390\/genes16050529","type":"journal-article","created":{"date-parts":[[2025,5,1]],"date-time":"2025-05-01T03:50:43Z","timestamp":1746071443000},"page":"529","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Development and Application of a TaqMan-Based qPCR Assay for Detecting ENTV-2 in Goats"],"prefix":"10.3390","volume":"16","author":[{"given":"Pengfei","family":"Li","sequence":"first","affiliation":[{"name":"State Key Laboratory for Animal Disease Control and Prevention, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, China"},{"name":"College of Veterinary Medicine, Gansu Agricultural University, Lanzhou 730070, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Haike","family":"Yin","sequence":"additional","affiliation":[{"name":"Baoji Animal Husbandry and Veterinary Center, Baoji 721001, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaoan","family":"Cao","sequence":"additional","affiliation":[{"name":"State Key Laboratory for Animal Disease Control and Prevention, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xi","family":"Lan","sequence":"additional","affiliation":[{"name":"State Key Laboratory for Animal Disease Control and Prevention, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jinyan","family":"Wu","sequence":"additional","affiliation":[{"name":"State Key Laboratory for Animal Disease Control and Prevention, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jijun","family":"He","sequence":"additional","affiliation":[{"name":"State Key Laboratory for Animal Disease Control and Prevention, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8386-0262","authenticated-orcid":false,"given":"Ligang","family":"Yuan","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, Gansu Agricultural University, Lanzhou 730070, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8016-0511","authenticated-orcid":false,"given":"Youjun","family":"Shang","sequence":"additional","affiliation":[{"name":"State Key Laboratory for Animal Disease Control and Prevention, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,4,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2245","DOI":"10.1099\/vir.0.19125-0","article-title":"Characterization of enzootic nasal tumour virus of goats: Complete sequence and tissue distribution","volume":"84 Pt 8","author":"Ortin","year":"2003","journal-title":"J. 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