Fonteque Graziela Vieira, da Silva Casa Mariana, Ribeiro Gianlucca Simão Nadal, da Silva Zigomar, Vogel Carla Ivane Ganz, Fonteque Joandes Henrique, da Costa Ubirajara Maciel, Giovambattista Guillermo, Takeshima Shin-Nosuke, Miletti Luiz Claudio
Graduate Program in Animal Science (PPGCA), State University of Santa Catarina (UDESC), Lages, Brazil.
Centro Universitario UNIFACVEST, Lages, SC, Brazil.
J Appl Genet. 2025 Aug 27. doi: 10.1007/s13353-025-01003-0.
Enzootic bovine leukosis (EBL) caused by the bovine leukosis virus (BLV) disturbs the immune response in bovines, leading to severe economic losses, with a possible impact on public health. EBL has no treatment or vaccine available, making the identification of genetic polymorphisms related to BLV resistance in locally adapted breeds like Crioula Lageana cattle valuable perspectives. This study aims to determine the presence of the BoLA-DRB3 alleles associated with susceptibility or resistance to BLV in Crioula Lageana cattle. For that, 208 Crioula Lageana bovines, spanning various ages, categories, and sexes, were subjected to blood sampling for DNA extraction for genetic characterization. The PCR targeted the 440-bp fragment of the env gene of the BLV and 284-bp for the alleles of the BoLA-DRB3 gene. The alleles were identified using Sanger sequencing, and the allele amount and frequency were determined by direct counting. For the determination of resistance or susceptibility, firstly the association between each allele and infection by BLV was determined using the chi-square test (p < 0.05), and then it was followed by an odds ratio analysis. The occurrence of BLV was 38.46% (80/208). The DRB3*12:01 allele was associated with resistance to BLV infection (p = 0.035, O.R. = 0.000. The presence of alleles linked to resistance to disease incidence highlights the potential to enhance genetic approaches in formulating management and control strategies for EBL in diverse cattle populations, with potential implications for livestock production, food safety, and public health.
由牛白血病病毒（BLV）引起的地方流行性牛白血病（EBL）扰乱牛的免疫反应，导致严重经济损失，并可能对公共卫生产生影响。EBL没有可用的治疗方法或疫苗，因此在像克里欧拉拉热纳牛这样的本地适应品种中鉴定与BLV抗性相关的基因多态性具有重要意义。本研究旨在确定克里欧拉拉热纳牛中与BLV易感性或抗性相关的BoLA-DRB3等位基因的存在情况。为此，对208头不同年龄、类别和性别的克里欧拉拉热纳牛进行采血以提取DNA用于基因特征分析。PCR靶向BLV env基因的440 bp片段以及BoLA-DRB3基因的等位基因的284 bp片段。使用桑格测序法鉴定等位基因，并通过直接计数确定等位基因数量和频率。为了确定抗性或易感性，首先使用卡方检验（p < 0.05）确定每个等位基因与BLV感染之间的关联，然后进行比值比分析。BLV的发生率为38.46%（80/208）。DRB3*12:01等位基因与对BLV感染的抗性相关（p = 0.035，O.R. = 0.000）。与疾病发病率抗性相关的等位基因的存在凸显了在为不同牛群制定EBL管理和控制策略时加强遗传方法的潜力，这对畜牧生产、食品安全和公共卫生可能具有重要意义。
