Project description:The impact of postnatal heat stress exposure in neonatal calves is not well-understood, and adequate heat abatement methods during the pre-weaning phase are lacking. This study aimed to investigate the impact of pre-weaning heat stress on liver gene expression profiles.
Project description:The impact of postnatal heat stress exposure in neonatal calves is not well-understood, and adequate heat abatement methods during the pre-weaning phase are lacking. This study aimed to investigate the impact of pre-weaning heat stress on liver DNA methylation profiles.
Project description:The objectives of the study were to use RNA-Seq to examine the effect of (i) breed and (ii) gradual weaning, on the whole blood mRNA transcriptome of artificially reared Holstein-Friesian and Jersey calves. The calves were gradually weaned over 14 days (day (d) -13 to d 0) and mRNA transcription was examined one day before gradual weaning was initiated (d -14), one day after weaning (d 1) and 8 days after weaning (d 8). RNA-seq analysis was carried out on RNA extracted from whole blood. Gradual weaning had no effect on gene expression (P>0.05).There were 550 differentially expressed genes at a false discovery rate of 10% and with a â¥1.5-fold change, between Holstein-Friesian and Jersey calves on d -14, 490 on d 1, and 411 on d 8. GOseq/KEGG pathway analysis showed that the cytokine-cytokine receptor interaction pathway and the neuroactive ligand-receptor interaction pathway were over-represented between breeds on all days (P<0.01; Qâ¤0.1). These results demonstrate that the gradual weaning practiced here does not compromise the welfare of artificially-reared dairy calves, evidenced by the lack of expression changes in any genes in response to gradual weaning. These data also suggest differences in cell signalling and immune responses between breeds. Eight Holstein-Friesian and eight Jersey bull calves were group housed indoors and individually fed milk replacer and concentrate using an automatic feeder. Calves were gradually weaned by reducing milk-replacer from 6 litres to 0 litres over 14 days (d) (d -13 to d 0). Calves were blood sampled on d -14, 1, and 8, relative to weaning (d 0). RNA-seq analysis was carried out on RNA extracted from whole blood.
Project description:The objectives of the study were to use RNA-Seq to examine the effect of (i) breed and (ii) gradual weaning, on the whole blood mRNA transcriptome of artificially reared Holstein-Friesian and Jersey calves. The calves were gradually weaned over 14 days (day (d) -13 to d 0) and mRNA transcription was examined one day before gradual weaning was initiated (d -14), one day after weaning (d 1) and 8 days after weaning (d 8). RNA-seq analysis was carried out on RNA extracted from whole blood. Gradual weaning had no effect on gene expression (P>0.05).There were 550 differentially expressed genes at a false discovery rate of 10% and with a ≥1.5-fold change, between Holstein-Friesian and Jersey calves on d -14, 490 on d 1, and 411 on d 8. GOseq/KEGG pathway analysis showed that the cytokine-cytokine receptor interaction pathway and the neuroactive ligand-receptor interaction pathway were over-represented between breeds on all days (P<0.01; Q≤0.1). These results demonstrate that the gradual weaning practiced here does not compromise the welfare of artificially-reared dairy calves, evidenced by the lack of expression changes in any genes in response to gradual weaning. These data also suggest differences in cell signalling and immune responses between breeds.
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.