One natural recombinant avian leukosis virus (ALV) strain GX14DJ3-18 was isolated from a native gamecock by DF-1 cell culture and identified with Polymerase Chain Reaction (PCR), immunofluorescence assay and the viral genome's nucleotide sequencing. This strain was revealed as a novel recombinant virus with nucleotide sequence similarities of 95.4% Long Terminal Repeated (LTR), 95.8% 5', UTR, 97.9% gag, and 92.9% 3'untranslated regions (UTR) in ALV-J. Also we found sequence similarities of 99.3% pol and 99.0% gp37 in ALV-E, and 89.9% gp85 in ALV-A. The simulated congenital infection with GX14DJ3-18 in Three-Yellow chickens exhibited a significant negative effect on the development of immune organs (P < 0.05). Also, lower antibody responses were found to vaccinations with the commercial vaccines of Newcastle disease virus and with subtypes H5 and H9 of avian influenza virus (P < 0.05). The incidence of tumor or tumor-like lesions in the challenged birds was 14.28% (5/35), while none were observed in the un-challenged control group (0/35). These results suggested that GX14DJ3-18 is a novel recombinant ALV that can induce pathogenicity in the commercial Three-Yellow chickens. We speculated that cross-provincial sales of gamecocks in which ALVs have not been eradicated thoroughly might be a potential route for the transmission of ALVs to commercial chickens.

中文翻译：

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一种从斗鸡中分离的新型重组禽白血病病毒对三黄鸡的致病性：禽白血病病毒对商品鸡的潜在感染源。

通过DF-1细胞培养从天然斗鸡中分离得到一株天然重组禽白血病病毒（ALV）GX14DJ3-18，并通过聚合酶链反应（PCR）、免疫荧光测定和病毒基因组核苷酸测序进行鉴定。该毒株是一种新型重组病毒，其与 ALV-J 中的长末端重复区 (LTR)、5'UTR 95.8%、gag 97.9% 和 3'非翻译区 (UTR) 的核苷酸序列相似性为 95.4%。我们还发现 ALV-E 中 pol 和 gp37 的序列相似性为 99.3%，ALV-A 中 gp85 的序列相似性为 89.9%。三黄鸡模拟先天性感染GX14DJ3-18对免疫器官发育有显着的负面影响（P < 0.05）。此外，接种新城疫病毒商品疫苗和禽流感病毒 H5 和 H9 亚型疫苗后，抗体反应较低（P < 0.05）。受攻击的鸟类中肿瘤或肿瘤样病变的发生率为14.28%（5/35），而在未受攻击的对照组中没有观察到肿瘤或肿瘤样病变的发生率（0/35）。这些结果表明GX14DJ3-18是一种新型重组ALV，可以对商品三黄鸡产生致病性。我们推测，未彻底根除ALV的斗鸡的跨省销售可能是ALV向商品鸡传播的潜在途径。