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Interleukin-12 (IL-12) and interleukin-23 (IL-23) are proinflammatory cytokines produced by macrophages and dendritic cells in response to infection with intracellular pathogens. Given the importance of IL-12 and IL-23 for modulating inflammation and the host immune response, the IL-12 and IL-23 receptor genes may be suitable candidate genes for studying disease resistance in dairy cattle. Twenty Chinese Holstein cows were selected randomly for PCR amplification and sequencing, and used for SNP discovery in the bovine IL-12Rβ2 and IL-23R promoter region. One SNP(c.-246G>T) in IL-12Rβ2 gene and 2 SNPs(c.-856A>G and c.-207T>C) in IL-23R gene were identified. Chinese Holstein cows (n=866) were then genotyped using Sequenom MassARRAY (Sequenom Inc., San Diego, CA) based on the 3 identified SNPs, and the associations between SNPs or haplotype of the genes and milk production traits, SCS were analyzed by the least squares method in the GLM procedure of SAS. The IL-23Rc.-856A>G and IL-23Rc.-207T>C showed close linkage disequilibrium (r2=0.89). No association was found with SCS, but associations were found between 3 of these SNP with milk protein content and lactose content. The software MatInspector revealed that these SNPs were located within several potential transcription factor binding sites, and may alter gene expression, but further investigation will be required to elucidate the biological and practical relevance of these SNP.

Associations between the stearoyl-CoA desaturase 1 (SCD1) gene and the Diacylglycerol-O-acyltransferase 1 (DGAT1) polymorphisms with milk production traits were analyzed using data from 1061 Chinese Holstein cows located in the Delta Region of Yangtze River in China. Milk production traits included test day observations for milk yield (TDMY), fat content (FC), protein content (PC), lactose content (LC), total solid (TS), milk urea nitrogen (MUN), somatic cell score (SCS), as well as lactation records, i.e. 305-day FCM yield, 305-day fat yield and 305-day protein yield. A total of 8,162 test day records were analyzed using a linear mixed model including the fixed effects of sire, herd, test year, test season, parity, calving season, milking day, gene locus, and the random effect of the cow. The effects of the SCD1 genotype on TDMY, FCM (fat corrected milk yield), FC, PC, SCS and 305-day FCM yield were analyzed. Cows with genotype AA produced significantly higher TDMY and FCM compared to cows with genotype AV or VV, but had lower values for FC and PC. Furthermore, the effects of the DGAT1 genotype on TDMY, FCM, FC, PC, TS, 305-day FCM, 305-day fat yield and 305-day protein yield were analyzed. Association studies revealed significantly lower TDMY, FCM and 305-day FCM yield for cows with genotype KK compared to genotypes KA or AA. In contrast, the KK genotype was superior with regard to FC, PC and TS. Cows with genotype KA produced higher 305-day fat yield and 305-day protein yield compared to genotypes AA or KK. These findings suggest a possible use of SCD1 and DGAT1 loci in marker-assisted selection programs for the improvement of milk production traits in dairy cattle from the Delta Region of Yangtze River in China.

The purpose of this study was to determine the feasibility of myocardial computed tomography perfusion (CTP) for the assessment of myocardial ischemia and infarction compared with cardiac magnetic resonance imaging (MRI). 82 patients with coronary artery disease who underwent adenosine stress