Giglioti Rodrigo, Oliveira Henrique Nunes, Ibelli Adriana Mércia Guaratini, Bilhassi Talita Barban, Néo Thalita Athiê, Santana Clarissa Helena, Rabelo Márcio Dias, Machado Rosângela Zacarias, de Souza Chagas Ana Carolina, de Sena Oliveira Márcia Cristina
Universidade Estadual Júlio de Mesquita Filho, Jaboticabal, SP, Brazil.
Universidade Estadual Júlio de Mesquita Filho, Jaboticabal, SP, Brazil.
Ticks Tick Borne Dis. 2017 Mar;8(3):335-340. doi: 10.1016/j.ttbdis.2016.11.008. Epub 2016 Nov 21.
With the aim of finding quantitative phenotypic traits that can be used to discriminate the levels of resistance/susceptibility to Babesia bovis, we estimated the repeatability and correlation between the level of infection, determined by the number of copies of a fragment of the gene that encodes cytochrome B (NC mt-cyB) of B. bovis, and the levels of the anti-B. bovis antibodies, in blood samples collected from 51 Angus cattle on two different occasions. Samples with the anticoagulant EDTA were used for DNA extraction and without anticoagulant for separation of the blood serum. The quantification of the NC mt-cyB of B. bovis was carried out by the quantitative PCR technique (qPCR), while the anti-B. bovis IgG antibody titers (S/P) were quantified by the ELISA method. The NC and S/P data were log10-transformed to improve the approximation to the normal distribution and were analyzed using mixed models. The correlations between NC mt-cyB and S/P were estimated, as well as the repeatability values for each trait. The results obtained showed the high sensitivity of the techniques, with 100% of the animals being positive for B. bovis, detected by both the serological and molecular tests. The correlations estimated between NC and S/P were low, 0.10 and 0.12, in the first and second collection, respectively. The repeatability estimated for NC was 0.06, whereas for the S/P it was 0.42. The low correlations between S/P and NC in the two collections demonstrated that the variation in the NC value is independent of the level of antibodies. This results indicated that animals with a higher levels of antibodies against B. bovis in the first collection continued to have a higher levels in the second one. However, the very low values for the repeatability value of NC, and for the correlations between S/P and NC, demonstrates that neither NC or S/P could be used to discriminate animals for resistance/susceptibility to B. bovis.
为了找到可用于区分牛对牛巴贝斯虫抗性/易感性水平的定量表型特征，我们估计了感染水平（由牛巴贝斯虫编码细胞色素B的基因片段（NC mt - cyB）的拷贝数确定）与抗牛巴贝斯虫抗体水平之间的重复性和相关性，这些数据来自于在两个不同时间从51头安格斯牛采集的血样。含有抗凝剂EDTA的样本用于DNA提取，不含抗凝剂的样本用于分离血清。牛巴贝斯虫的NC mt - cyB定量通过定量PCR技术（qPCR）进行，而抗牛巴贝斯虫IgG抗体滴度（S/P）通过ELISA方法定量。对NC和S/P数据进行log10转换以改善与正态分布的近似度，并使用混合模型进行分析。估计了NC mt - cyB与S/P之间的相关性以及每个性状的重复性值。获得的结果表明这些技术具有高灵敏度，血清学和分子检测均检测到100%的动物对牛巴贝斯虫呈阳性。在第一次和第二次采集时，估计的NC与S/P之间的相关性较低，分别为0.10和0.12。估计的NC重复性为0.06，而S/P的重复性为0.42。两次采集中S/P与NC之间的低相关性表明NC值的变化与抗体水平无关。这一结果表明，在第一次采集中抗牛巴贝斯虫抗体水平较高的动物在第二次采集中仍然具有较高水平。然而，NC的重复性值以及S/P与NC之间的相关性非常低，这表明NC或S/P均不能用于区分动物对牛巴贝斯虫的抗性/易感性。
