Borjigin Liushiqi, Lo Chieh-Wen, Bai Lanlan, Hamada Rania, Sato Hirotaka, Yoneyama Shuji, Yasui Anna, Yasuda Sohei, Yamanaka Risa, Mimura Munehito, Inokuma Michihito, Shinozaki Yasuo, Tanaka Naoko, Takeshima Shin-Nosuke, Aida Yoko
Viral Infectious Diseases Unit, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
Baton Zone Program, Nakamura Laboratory, RIKEN Cluster for Science, Technology and Innovation Hub, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
Pathogens. 2021 Apr 22;10(5):502. doi: 10.3390/pathogens10050502.
Perinatal transmission plays a critical role in the spread of bovine leukemia virus (BLV) infection in cattle herds. In the Holstein breed, we previously identified BLV resistant and susceptible bovine leukocyte antigen ()- alleles, including - and with a low BLV proviral load (PVL), and and with a high PVL. Here, we evaluated the perinatal BLV transmission risk in dams with different alleles. alleles of 120 dam-calf pairs from five dairy farms in Japan were identified; their PVL was quantified using the BLV-Coordination of Common Motifs (CoCoMo)-qPCR-2 assay. Ninety-six dams were BLV-positive, and 29 gave birth to BLV-infected calves. Perinatal transmission frequency was 19% in dams with resistant alleles suppressed to a low PVL level, and 38% and 25% in dams with susceptible and neutral alleles that maintained high PVL levels, respectively. Notably, all calves with resistant alleles were BLV free, whereas 30% of calves with susceptible genes were infected. Thus, vertical transmission risk was extremely lower for dams and calves with resistant alleles compared to those with susceptible alleles. Our results can inform the development of effective BLV eradication programs under field conditions by providing necessary data to allow for optimal selection of dams for breeding.
围产期传播在牛白血病病毒（BLV）感染在牛群中的传播中起着关键作用。在荷斯坦品种中，我们之前鉴定出了对BLV有抗性和易感性的牛白细胞抗原（）等位基因，包括病毒前病毒载量（PVL）较低的 - 和 ，以及PVL较高的 和 。在此，我们评估了具有不同 等位基因的母畜的围产期BLV传播风险。鉴定了来自日本五个奶牛场的120对母畜 - 犊牛对的 等位基因；使用BLV-共有基序协调（CoCoMo）-qPCR-2检测法对它们的PVL进行了定量。96头母畜为BLV阳性，其中29头产下了感染BLV的犊牛。抗性等位基因被抑制到低PVL水平的母畜的围产期传播频率为19%，而维持高PVL水平的易感和中性等位基因的母畜的围产期传播频率分别为38%和25%。值得注意的是，所有具有抗性等位基因的犊牛均未感染BLV，而具有易感基因的犊牛中有30%被感染。因此，与具有易感等位基因的母畜和犊牛相比，具有抗性等位基因的母畜和犊牛的垂直传播风险极低。我们研究结果可为制定有效的野外条件下BLV根除计划提供信息，通过提供必要数据以便为育种选择最佳母畜。
