Project description:Newly-hatched domestic chick serves as an important model for studies of neural and behavioral plasticity, particularly with respect to learning and memory such as filial imprinting. Imprinting is assumed to be a unique case of recognition learning with some characteristic features, such as sensitive period and irreversibility. However, the molecules involved in the memory process are yet to be fully identified. To address this issue, we attempted to identify the genes differentially expressed at an earlier phase of filial imprinting than described in our previous report (Brain Res. Bull.76, 275-281 (2008)). One-day-old chicks were trained for imprinting for 1 h and whole brains were collected and used for cDNA microarray analysis and quantitative RT-PCR. We identified 18 genes upregulated accompanying filial imprinting. These results suggested that the increase of these 18 genes associated with filial imprinting might play an important role in the acquisition of memory in the filial imprinting.
Project description:Optimization of broiler chicken breast muscle protein accretion is key for the efficient production of poultry meat, whose demand is steadily increasing. In a context where antimicrobial growth promoters use is being restricted, it is important to find alternatives as well as to characterize the effect of immunological stress on broiler chicken growth. Despite of its importance, research on broiler chicken muscle protein dynamics has been mostly limited to the study of mixed protein turnover. The present study aims to characterize the effect of a bacterial challenge and the feed supplementation of a citrus and a cucumber extract on broiler chicken individual breast muscle proteins fractional synthesis rates (FSR) using a recently developed dynamic proteomics pipeline. 21 day-old broiler chickens were administered a single 2H2O dose before being culled at different timepoints. A total of 60 breast muscle protein extracts from five experimental groups (Unchallenged, Challenged, Control Diet, Diet 1 and Diet 2) were analyzed using a DDA proteomics approach. Proteomics data was filtered in order to reliably calculate multiple proteins FSR making use of a newly developed bioinformatics pipeline. Broiler breast muscle proteins FSR uniformly decreased following a bacterial challenge, this change was judged significant for 15 individual proteins, the two major functional clusters identified as well as for mixed breast muscle protein. Citrus or cucumber extract feed supplementation did not show any effect on the breast muscle protein FSR of immunologically challenged broilers. The present study has identified potential predictive markers of breast muscle growth and provided new information on broiler chicken breast muscle protein turnover which could be essential for improving the efficiency of broiler chicken meat production.
Project description:As an essential micronutrient for animals, vitamin E plays crucial physiological roles in reproduction, antioxidant and immune functions, and lipid metabolism. The objective of this study was to reveal molecular mechanism of vitamin E on intramuscular fat (IMF) deposition through transcriptome sequencing of pectoral muscle in broiler chickens. A total of 240 one-day-old health female chicks were randomly allocated into five dietary treatments with each treatment six replicates. The birds were fed basal diet supplemented with 0 and 100 IU/kg vitamin E in the form of DL-α-tocopheryl acetate, respectively. The body weight, carcass performance and IMF content were measured. Transcriptome profile of pectoral muscle in 35-day-old chickens were sequencing from the control and 100 IU/kg vitamin E treatment. Functional enrichment analyzes of differentially expressed genes (DEGs) based on Gene ontology (GO), KEGG pathway and bio function, and network were performed. Results shown that IMF content of broiler chickens were significantly increased at 12.89% (P < 0.05) between 100 IU/kg vitamin E treatment and control. Transcriptome sequencing results for pectoralis major muscle of 100 IU vitamin E-supplemented and the control groups identified 57 up-regulated and 102 down-regulated DEGs. These DEGs were significantly enriched (FDR corrected P-value < 0.05) in 13 of 236 GO terms involved in muscle development- and lipid metabolism. Pathway functional enrichment analysis revealed that the DEGs were significantly enriched in three signalling pathways (FDR corrected P-value < 0.05). Two of them, MAPK signaling pathway and FoxO signaling pathway, play key roles in muscular and lipid metabolism. It is worth mentioning that 46 DEGs were significantly enriched in 28 skeletal and muscular system development and function categories and 31 DEGs were significantly enriched in 17 lipid metabolism function categories. Moreover, three lipid metabolism and muscular development-related networks of DEGs were also identified. These DEGEs, pathways, function categories and networks identified in this study provide us new insights for the vitamin E regulation of the IMF deposition in broiler chickens.
Project description:Domestic broiler chickens rapidly accumulate adipose tissue due to intensive genetic selection for rapid growth and are naturally hyperglycemic and insulin resistant, making them an attractive addition to the suite of rodent models used for studies of obesity and type 2 diabetes in humans. Furthermore, chicken adipose tissue is considered as poorly sensitive to insulin and lipolysis is under glucagon control. Excessive fat accumulation is also an economic and environmental concern for the broiler industry due to the loss of feed efficiency and excessive nitrogen wasting, as well as a negative trait for consumers who are increasingly conscious of dietary fat intake. Understanding the control of avian adipose tissue metabolism would both enhance the utility of chicken as a model organism for human obesity and insulin resistance and highlight new approaches to reduce fat deposition in commercial chickens. In the present study we simultaneously characterized the effects of a short term (5 hours) fast or neutralization of insulin action (5 hours) on adipose tissue of young (16-17 day-old), fed commercial broiler chickens.
Project description:Relative expression levels of mRNAs in chicken cecal epithelia experimentally infected with Eimeria tenella were measured at 4.5 days post-infection. Two weeks old chickens were uninfected (negative control) or were orally inoculated with sporulated oocysts of Eimeria tenella. Cecal epithelia samples were collected from >12 birds in infected or uninfected group at 4.5 d following infections, in which samples from 4 birds were pooled together to form a total 3 biological replicates in each group. Parasite merozoites were also collected from four infected chickens at 5 d after infections. Uninfected control samples, merozoites and infection group samples were selected for RNA extraction and hybridization on Affymetrix microarrays. We used Affymetrix GeneChip chicken genome arrays to detail the chicken cecal epithelia gene expression in the control and E. tenella-infected birds.
Project description:Newly-hatched domestic chick serves as an important model for studies of neural and behavioral plasticity, particularly with respect to learning and memory such as filial imprinting. Imprinting is assumed to be a unique case of recognition learning with some characteristic features, such as sensitive period and irreversibility. However, the molecules involved in the memory process are yet to be fully identified. To address this issue, we attempted to identify the genes differentially expressed at an earlier phase of filial imprinting than described in our previous report (Brain Res. Bull.76, 275-281 (2008)). One-day-old chicks were trained for imprinting for 1 h and whole brains were collected and used for cDNA microarray analysis and quantitative RT-PCR. We identified 18 genes upregulated accompanying filial imprinting. These results suggested that the increase of these 18 genes associated with filial imprinting might play an important role in the acquisition of memory in the filial imprinting. Total RNA was extracted from whole brains of trained chicks (n=16) and control dark-reared chicks (n=16). Using these total RNAs, we performed RT-PCR to distinguish male chicks from females. Then total RNAs were separated and mixed in four groups (1, male trained (n=8); 2, female trained (n=8); 3, male dark-reared (n=8); and 4, female dark-reared chicks (n=8)), and we performed cDNA microarray expression analysis to identify the upregulated genes following imprinting (1 versus 3 and 2 versus 4).