Project description:The aim of the overall study was to investigate the development of immune competence in artificially reared dairy calves and in two breeds of naturally suckled beef calves over the first 168h of life. Dairy calves were fed 5% total body weight of colostrum, with beef calves monitored to ensure natural ingestion of colostrum. Blood samples were taken from all calves at 24h 48h 72h and 168h, and analysed for alterations to immunes genes.
Project description:Serotonin is a monoamine that regulates processes such as energy balance and immune function. Manipulating this pathway in growing dairy calves could promote growth and development by modulating functions and signaling pathways within key organs. In this study, we characterized the adipose and muscle transcriptome of pre-weaned calves with increased serotonin bioavailability through the elucidation of differentially expressed genes.
Project description:The aim of this study was to identify changes in transcriptome of parenchyma (PAR), fat pad (MFP) and liver in dairy calves. Our earlier results showed that feeding management regulates the dynamics of organ growth in preweaned heifers. We observed that a daily dose of 5.3 kg of milk replacer inhibits mammary gland development. Therefore, this research aims at evaluation of the influence of the nutritional level in the early life period of calves on the biological processes related to the development of the mammary gland through transcriptomic alterations.
Project description:The consumption of fermented food has been linked to positive health outcomes due to a variety of functional properties. Fermented dairy constitutes a major dietary source and contains lactoseas main carbohydrate and living starter cultures. To investigate whether nutritional and microbial modulation impacted intestinal microbiota composition and activity, we employed fecal microbiota fermentations and a dairy model system consisting of lactose and β-galactosidase positive and negative Streptococcus thermophilus. Based on 16S rRNA gene based microbial community analysis, we observed that lactose addition increased the abundance of Bifidobacteriaceae, and of Veillonellaceae and Enterobacteraceae in selected samples. The supplied lactose was hydrolysed within 24 h of fermentation and led to higher expression of community indigenous β-galactosidases. Targeted protein analysis confirmed that bifidobacteria contributed most β-galactosidases together with other taxa including Escherichia coli and Anaerobutyricum hallii. Lactose addition led to 1.1-1.8 fold higher levels of butyrate compared to controls likely due to (i) lactate-crossfeeding and (ii) direct lactose metabolism by butyrate producing Anaerobutyricum and Faecalibacterium spp. Representatives of both genera used lactose to produce butyrate in single cultures. When supplemented at around 5.5 log cells mL-1, S. thermophilus or its beta-galactosidase negative mutant outnumbered the indigenous Streptococcaceae population at the beginning of fermentation but had no impact on lactose utilisation and final SCFA profiles. This study brings forward new fundamental insight into interactions of major constituents of fermented dairy with the intestinal microbiota. We provide evidence that lactose addition increases fecal microbiota production of butyrate through cross-feeding and direct metabolism without contribution of starter cultures.
Project description:Bovine Herpesvirus 1 (BoHV-1) is a leading cause of Bovine Respiratory Disease (BRD) in young calves, which is responsible for substantial morbidity and mortality. Therefore, the objective of the current study was to elucidate the whole blood mRNA transcriptomic response to an experimental challenge with BoHV-1, in dairy calves. Holstein-Friesian calves were either challenged by intranasal atomisation with BoHV1 virus (6.3 x 10^7/mL x 1.35mL) (n=12) or mock challenged with sterile phosphate buffered saline (n=6). Clinical signs were scored daily until euthanasia at day 6 post-challenge. Total RNA was extracted and sequenced from whole blood (100 bp paired-end). Sequence reads were aligned to the ARS-UCD1.2 bovine reference genome and differential gene expression analysis was performed using EdgeR. An MDS plot displayed an obvious separation between BoHV-1 challenged and control calves based on the gene expression changes in whole blood. There were 488 differentially expressed (DE) genes (p < 0.05, FDR < 0.1, fold change > 2) between the BoHV-1 challenged and control calves.
Project description:Bovine Respiratory Syncytial Virus (BRSV) is a leading cause of Bovine Respiratory Disease (BRD) in young calves, which is responsible for substantial morbidity and mortality. Infection with BRSV induces global gene expression changes in respiratory tissues. If these changes are observed in tissues which are accessible in live animals, such as whole blood, they may be used as biomarkers of the disease. Therefore, the objective of the current study was to elucidate the whole blood transcriptomic response to an experimental challenge with BRSV, in dairy calves. Holstein-Friesian calves were either inoculated with virus (103.5 TCID50/ml x 15 ml) (n=12) or mock challenged with sterile phosphate buffered saline (n=6). Clinical signs were scored daily and whole blood was collected in Tempus RNA tubes immediately prior to euthanasia, at day 7 post-challenge. RNA was extracted from blood and sequenced (150 bp paired-end). Sequence reads were aligned to the UMD3.1 bovine reference genome and differential gene expression analysis was performed using EdgeR. An MDS plot displayed an obvious separation between BRSV challenged and control calves based on whole blood gene expression changes, despite an observed mild clinical manifestation of the disease. There were 281 differentially expressed (DE) genes (p < 0.05, FDR < 0.1, fold change > 2) between the BRSV challenged and control calves. The top enriched KEGG pathways and gene ontology terms were associated with viral infection and included “Influenza A”, “defense response to virus”, “regulation of viral life cycle” and “innate immune response”. Highly DE genes involved in these pathways are may be beneficial for the diagnosis of subclinical BRD from blood samples.