ABSTRACT: Differential gene expression in the muscle tissue of crossbred beef cows with divergent gain after feed restriction and ad libitum feeding studies.
Project description:Differential gene expression in the adipose tissue of crossbred beef cows with divergent gain after feed restriction and ad libitum feeding studies.
Project description:Our objectives were to compare gene expression profiles in neutrophils (PMN) during a Streptococcus uberis mastitis challenge between lactating cows subjected to feed restriction to induce negative energy balance (NEB; n = 5) and cows fed ad libitum to maintain positive energy balance (PEB; n = 5). The NEB cows were feed-restricted to 60% of calculated net energy for lactation requirements for 7 d, whereas PEB cows were fed the same diet for ad libitum intake. After 5 d of feed restriction, one rear mammary quarter of each cow was inoculated with 5,000 cfu of Streptococcus uberis (strain O140J). Blood PMN were isolated at 24 h post-inoculation from all cows for RNA extraction and microarray analysis. NEB resulted in 94 differentially expressed genes compared with PEB. Of these, 51 genes were down-regulated, including genes involved with antigen presentation (HLADRA and HLAA), respiratory burst (SOD1), and the pro-inflammatory response (TNFA and IRAK-1). The most affected genes up-regulated by NEB (n = 43) included IL1R2 and IL6, toll-like receptors (TLR2 and TLR4), and THY1. Network analysis by Ingenuity Pathway Analysis ® revealed that TNFA was associated with the expression of numerous differentially expressed genes involved with immune response in NEB cows compared with PEB cows. Energy balance alters PMN expression of several genes involved with immune response, which provides new information on transcriptomic mechanisms associated with post-partal NEB and immune response during early lactation. Briefly, 10 multiparous Holstein cows in PEB and past peak lactation were used for this study. The NEB cows were feed-restricted to 60% of calculated NEL requirements for 7 d, whereas PEB cows were fed the same diet for ad libitum intake. After 5 d of feed restriction, one rear mammary quarter of each cow was inoculated with 5,000 cfu of Streptococcus uberis (strain O140J). Blood PMN were isolated at 24 h post-inoculation from all cows. A 13,257-oligonucleotide (70-mers) array was used for transcript profiling. Cy3- and Cy5 labelled cDNA from PMN and a reference standard were used for hybridizations. All samples were hybridized to duplicate slides with reverse labeling (20 microarrays total).
Project description:Beef cow adipose tissue transcriptome Evaluation of the naturally occurring transcriptome variation among beef cows with divergent gain.
Project description:Our objectives were to compare gene expression profiles in neutrophils (PMN) during a Streptococcus uberis mastitis challenge between lactating cows subjected to feed restriction to induce negative energy balance (NEB; n = 5) and cows fed ad libitum to maintain positive energy balance (PEB; n = 5). The NEB cows were feed-restricted to 60% of calculated net energy for lactation requirements for 7 d, whereas PEB cows were fed the same diet for ad libitum intake. After 5 d of feed restriction, one rear mammary quarter of each cow was inoculated with 5,000 cfu of Streptococcus uberis (strain O140J). Blood PMN were isolated at 24 h post-inoculation from all cows for RNA extraction and microarray analysis. NEB resulted in 94 differentially expressed genes compared with PEB. Of these, 51 genes were down-regulated, including genes involved with antigen presentation (HLADRA and HLAA), respiratory burst (SOD1), and the pro-inflammatory response (TNFA and IRAK-1). The most affected genes up-regulated by NEB (n = 43) included IL1R2 and IL6, toll-like receptors (TLR2 and TLR4), and THY1. Network analysis by Ingenuity Pathway Analysis ® revealed that TNFA was associated with the expression of numerous differentially expressed genes involved with immune response in NEB cows compared with PEB cows. Energy balance alters PMN expression of several genes involved with immune response, which provides new information on transcriptomic mechanisms associated with post-partal NEB and immune response during early lactation.
Project description:Growing ruminants maintained under dietary restriction for extended periods will exhibit compensatory growth when reverted to ad libitum feeding. This period of compensatory growth is associated with increased feed efficiency, lower basal energy requirements, and changes in circulating concentrations of metabolic hormones. To identify genetic mechanisms contributing to these physiological changes, 8 month-old steers were fed either ad libitum (control; n = 6) or 60-70% of intake of control animals (feed-restricted; n=6) for a period of 12 weeks. All steers were then fed ad libitum for the remaining 8 weeks of the experiment (realimentation period). Liver was biopsied from each animal at days -14, +1 and +14 relative to realimentation for RNA extraction and gene expression analysis by microarray hybridization.
Project description:In a previous study, 50% calorie restriction in mice from days 1.5-11.5 of pregnancy resulted in reduced placental weights and areas, relatively sparing of labyrinth zone area compared to junctional zone area, and dramatic changes in global gene expression profiles. Here we examined placental gene expression at day 18.5, after the return to normal feeding to see whether differences were reversible Mice were randomized to 2 treatment groups on day 1.5 of pregnancy: (1) ad libitum fed (control) (2) 50% food restriction (restricted). Mice were returned to ad libitum feed on d11.5, sacrificed on d18.5 and placentas were collected.
Project description:The objective of this study was to examine changes in hepatic gene expression of growing bulls during a period of dietary energy restriction followed by a period of subsequent realimentation and compensatory growth. Purebred Holstein Friesian bulls (n=20) were assigned to one of two feeding treatments (i) restricted feed allowance for 125 days (n=10) followed by ad libitum access to feed for a further 55 days or (ii) a control group with ad libitum access to feed through out the 180 days trial (n=10). The first 125 days of the trial were denoted as Peirod 1, during which treatment groups were fed differentially. The subsequent 55 days, denoted as Period 2 during which all bulls were fed ad libitum. All bulls received the same diet of 70% concentrate 30% grass silage through out the experimental trial,with the amount of feed provided different dependnet on each treatment group. At the end of each period, 10 animals from each treatment group (10, restricted fed and 10 ad libitum fed) were slaughtered and hepatic tissue collected within thirty minutes of slaughter. RNA was extracted and hepatic gene expression was examined using RNAseq technology and bioinformatic analysis. During the differential feeding period, over-represented pathways including amino acid and lipid metabolism, protein synthesis and cell cycle/proliferation were identified, which indicate alterations in metabolic and growth rate in the liver during dietary restriction . During the realimentation period, pathways involved in cell cycle and cell growth as well as protein synthesis were over-represented, with the direction of fold changes opposite to that of these pathways in Period 1. This information can be exploited in genomic breeding programmes to assist selection of cattle with a greater ability to compensate following a period dietary restriction.
Project description:Cows were selected from two groups of 12 cows enrolled in a large experiment to assess the effects of ad libitum or restricted intake of moderate-energy diets during the entire dry period on pre-partum metabolism and post-partum metabolism and performance. A corn silage-based diet (26% of diet dry matter) providing 1.59 Mcal/kg during the far-off dry period (first 5 wk of an 8-wk dry period) or providing 1.61 Mcal/kg during the close-up dry period (last 3 wk of the dry period) was fed for ad libitum or restricted intake. Four multiparous Holstein cows were randomly selected from the ad libitum and restricted intake groups. Keywords: time course, ad libitum or restricted feeding prepartum
Project description:Transcriptional profiling in liver of 24 pigs of 115 kg body weight from lines divergently selected for residual feed intake (RFI): low-RFI pigs fed ad libitum (RFIneg), high-RFI pigs fed ad libitum (RFIpl) and high-RFI pigs restricted at RFIneg feeding level (RFIplR) to investigate the impact of feeding independently of selection.