Hu D, Rampoldi A, Bratus-Neuenschwander A, Hofer A, Bertschinger H U, Vögeli P, Neuenschwander S
Institute of Agricultural Sciences, ETH Zurich, Tannenstrasse 1, 8092, Zurich, Switzerland.
SUISAG, Allmend 8, 6204 Sempach, Switzerland.
Anim Genet. 2019 Apr;50(2):136-142. doi: 10.1111/age.12770. Epub 2019 Feb 6.
The F4ac receptor locus (F4acR), which encodes susceptibility or resistance to Escherichia coli diarrhoea, is inherited as an autosomal recessive monogenetic trait. F4acR is localized on pig chromosome 13 (SSC13q41-q44) near the MUC13 gene. Two flanking markers (CHCF1 and ALGA0106330) with a high linkage disequilibrium (LD) with F4acR were found to be effective for the genetic identification of F4ac-resistant pigs in the Swiss Large White breed (one recombinant out of 2034 genotyped pigs). Three recombinant boars, one each from the Duroc, Swiss Landrace and Piétrain breeds, were genotyped with seven different markers and phenotyped by means of a microscopic adhesion test. Only ALGA0072075, CHCF1 and CHCF3 indicated the correct phenotype. To test the effect of the resistance allele on production traits, 530 Large White pigs from the national test station were investigated. A significant difference existed among the F4acR locus genotypes in the intramuscular fat content of the longissimus dorsi muscle, whereas no other production traits were influenced by the resistance allele. The frequency of the CHCF1-C and ALGA0106330-A alleles associated with resistance in the Swiss Large White population was 60%, which is advantageous for implementing this trait in a breeding programme to select for E. coli F4ac-resistant animals. The selection of resistant pigs should start on the male side due to the inability of resistant sows to produce sufficient amounts of protecting antibodies in the colostrum. Selection of genetically F4ac-resistant pigs is a sustainable and suitable alternative to decreasing animal loss and antibiotic use due to diarrhoea.
F4ac受体基因座（F4acR）编码对大肠杆菌腹泻的易感性或抗性，以常染色体隐性单基因性状形式遗传。F4acR定位于猪的13号染色体（SSC13q41 - q44）上，靠近MUC13基因。发现两个与F4acR具有高连锁不平衡（LD）的侧翼标记（CHCF1和ALGA0106330）对瑞士大白猪品种中F4ac抗性猪的基因鉴定有效（在2034头基因分型猪中有一头重组猪）。对三头分别来自杜洛克、瑞士长白和皮特兰品种的重组公猪用七种不同标记进行基因分型，并通过显微镜粘附试验进行表型分析。只有ALGA0072075、CHCF1和CHCF3显示出正确的表型。为了测试抗性等位基因对生产性状的影响，对来自国家试验站的530头大白猪进行了调查。背最长肌的肌内脂肪含量在F4acR基因座基因型之间存在显著差异，而没有其他生产性状受抗性等位基因影响。瑞士大白猪群体中与抗性相关的CHCF1 - C和ALGA0106330 - A等位基因频率为60%，这有利于在育种计划中实施该性状以选择抗大肠杆菌F4ac的动物。由于抗性母猪在初乳中不能产生足够量的保护性抗体，抗性猪的选择应从公猪开始。选择遗传上抗F4ac的猪是减少因腹泻造成的动物损失和抗生素使用的一种可持续且合适的替代方法。
