The use of Kosher phenotyping for mapping QTL affecting susceptibility to bovine respiratory disease

• Published in: Journal of animal science Vol. 94; p. 149
• Main Authors: Lipkin, E, Strillacci, M G, Eitam, H, Yishay, M, Schiavini, F, Soller, M, Bagnato, A, Shabtay, A
• Format: Journal Article
• Language: English
• Published: Champaign Oxford University Press 01.09.2016
• Subjects: Abattoirs; Animals; Calves; Deoxyribonucleic acid; DNA; Evaluation; Gene expression; Gene mapping; Genome-wide association studies; Genotype & phenotype; Immunology; Infections; Lungs; Mapping; Morbidity; Phenotypes; Phenotyping; Quantitative trait loci; Respiratory diseases; Wound healing
• ISSN: 0021-8812

Bovine respiratory disease (BRD). caused by multiple pathogens that become more virulent in response to stress, is the leading cause of morbidity and mortality in feedlot cattle. As various preventive strategies failed, marker or gene assisted selection for resistance becomes attractive. In the present study, selective DNA pooling was applied in a genome-wide association study to map BRD QTLs in Israeli Holstein male calves. Kosher scoring at the abattoir was used to allocate 122 and 62 animals to High and Low BRD resistant groups, respectively. Kosher scoring involves examination of the lungs for adhesions, a consequence of secondary bacterial infection in BRD. and hence a marker for individual history of BRD infections. Animals are graded Glatt (adhesions absent; assigned to High group). Kosher (moderate adhesions) and Treif (severe adhesions; assigned to Low group). All pools were genotyped by Illumina BovineHD BeadChip. Moving average of-logP was used to map QTLs and 1 Log drop was used to define QTL boundaries (QTLRs). The combined procedure was efficient for high resolution mapping. Nineteen QTLRs distributed over 13 autosomes were found, some overlapping previous studies. The QTLRs contain polymorphic functional and expression candidate genes, with putative immunological and wound healing activities that might affect kosher grade. Kosher grading was shown to be a low cost, easily collected phenotype for mapping QTLs affecting BRD morbidity.