Project description:This project aimed to characterise the immune response of cattle to buffalo fly infestation using cattle serum samples. The cattle were phenotyped into two groups, high buffalo fly burden and low buffalo fly burden cattle, following exposure to buffalo flies. The SWATH analysis was sued to measure the relative abundance of proteins in serum samples of the two groups at different time points.
Project description:Genomic structural variation is an important and abundant source of genetic and phenotypic variation. Here we describe the first systematic and genome-wide analysis of copy number variations (CNVs) in modern domesticated cattle using array comparative genomic hybridization (array CGH), quantitative PCR (qPCR) and fluorescent in situ hybridization (FISH). The array CGH panel included 90 animals from 11 Bos taurus, 3 Bos indicus and 3 composite breeds for beef, dairy or dual purpose. We identified over 200 candidate CNV regions (CNVRs) in total and 177 within known chromosomes, which harbor or are adjacent to gains or losses. These 177 high-confidence CNVRs cover 28.1 mega bases or ~1.07% of the genome. Over 50% of the CNVRs (89/177) were found in multiple animals or breeds and analysis revealed breed-specific frequency differences and reflected aspects of the known ancestry of these cattle breeds. Selected CNVs were further validated by independent methods using qPCR and FISH. Approximately 67% of the CNVRs (119/177) completely or partially span cattle genes and 61% of the CNVRs (108/177) directly overlap with segmental duplications. The CNVRs span about 400 annotated cattle genes that are significantly enriched for specific biological functions such as immunity, lactation, reproduction and rumination. Multiple gene families, including ULBP, have gone through ruminant lineage-specific gene amplification. We detected and confirmed marked differences in their CNV frequencies across diverse breeds, indicating that some cattle CNVs are likely to arise independently in breeds and contribute to breed differences. Our results provide a valuable resource beyond microsatellites and single nucleotide polymorphisms to explore the full dimension of genetic variability for future cattle genomic research.
Project description:While cold stress has been shown to seriously impact cattle industry, there are only a few reports investigating the effect of cold stress on cattle. Whether severe cold stress results in alterations in gene expression and affects molecular genetic mechanisms remains unknown. We used microarrays to analyze the alterations in gene expression in peripheral blood samples in response to cold exposure and identified differentially regulated genes. This study was performed on 30 healthy Sanhe heifers with similar genetic backgrounds, weight, and age. In order to induce cold stress, the cattle were transferred outdoor and were exposed to a temperature of -32°C for 3 hours followed by housing in cowshed at 5°C for 15 hours. Blood samples with EDTA were collected from each animal before and after the cold exposure. After total RNA was isolated from blood cells, six RNA samples (three derived before and three after the cold exposure), were collected from three animals randomly selected from the 30 healthy heifers for gene expression profiling in response to severe cold stress.
Project description:Genomic structural variation is an important and abundant source of genetic and phenotypic variation. Here we describe the first systematic and genome-wide analysis of copy number variations (CNVs) in modern domesticated cattle using array comparative genomic hybridization (array CGH), quantitative PCR (qPCR) and fluorescent in situ hybridization (FISH). The array CGH panel included 90 animals from 11 Bos taurus, 3 Bos indicus and 3 composite breeds for beef, dairy or dual purpose. We identified over 200 candidate CNV regions (CNVRs) in total and 177 within known chromosomes, which harbor or are adjacent to gains or losses. These 177 high-confidence CNVRs cover 28.1 mega bases or ~1.07% of the genome. Over 50% of the CNVRs (89/177) were found in multiple animals or breeds and analysis revealed breed-specific frequency differences and reflected aspects of the known ancestry of these cattle breeds. Selected CNVs were further validated by independent methods using qPCR and FISH. Approximately 67% of the CNVRs (119/177) completely or partially span cattle genes and 61% of the CNVRs (108/177) directly overlap with segmental duplications. The CNVRs span about 400 annotated cattle genes that are significantly enriched for specific biological functions such as immunity, lactation, reproduction and rumination. Multiple gene families, including ULBP, have gone through ruminant lineage-specific gene amplification. We detected and confirmed marked differences in their CNV frequencies across diverse breeds, indicating that some cattle CNVs are likely to arise independently in breeds and contribute to breed differences. Our results provide a valuable resource beyond microsatellites and single nucleotide polymorphisms to explore the full dimension of genetic variability for future cattle genomic research. The custom aCGH chips that interrogated the whole genome CNVs were build for 90 cattles from diverse breeds, with Hereford L1 Dominette 01449 as refference sample.
Project description:While cold stress has been shown to seriously impact cattle industry, there are only a few reports investigating the effect of cold stress on cattle. Whether severe cold stress results in alterations in gene expression and affects molecular genetic mechanisms remains unknown. We used microarrays to analyze the alterations in gene expression in peripheral blood samples in response to cold exposure and identified differentially regulated genes.
Project description:This project aimed to discover the protein-based biomarkers for tick resistance in cattle using cattle serum samples. The cattle were phenotyped into two groups, tick-resistant and susceptible after an artificial tick challenge. Mean tick scores were used to categorise cattle. The SWATH analysis was sued to measure the relative abundance of proteins in skin samples of the two groups at different time points.
Project description:This project aimed to discover the protein-based biomarkers for tick resistance in cattle using cattle skin samples. The cattle were phenotyped into two groups, tick-resistant and susceptible after artificial tick challenge. Mean tick scores were used to categorise cattle. The SWATH analysis was sued to measure the relative abundance of proteins in skin samples of the two groups at different time points.