Fatty Acid Composition and Regulatory Gene Expression in Late-Term Embryos of ACRB and COBB Broilers

Abstract

Cobb broilers (COBB) have been heavily selected for their production performance in the past several decades, while the Athens Canadian Random Bred (ACRB) chickens, a meat-type breed, have been kept as a non-selected control strain. The purpose of this study was to compare these two lines of chickens at late embryonic development and identify the molecular markers and fatty acid profiles underlining their differences in growth performance due to selection. Fertilized eggs of the ACRB (n = 6) and COBB (n = 6) were used at 14 and 18 embryonic days. Genes involved in lipogenesis and myogenesis were measured using quantitative real-time reverse transcroptionpolymerase chain reaction (RT-PCR), and fatty acid (FA) compositions of egg yolk, muscle, and liver were measured using gas chromatography. COBB had higher egg weight, embryo weight, and breast and fat ratio. The gene expression in the liver showed an interaction between age and breed on FASN expression, with the highest level in COBB at E18. ACRB had higher ApoB and MTTP expression, but lower SREBP-1 expression compared to COBB. No difference was found in myogenesis gene expression in the muscle between two breeds. For the FA composition, muscle was largely affected by both breed and age. Yolk and liver were affected mainly by breed and age, respectively. Constant interaction effects in docosahexaenoic acid (DHA), indicating the highest level in all the tested tissues of ACRB at E14 and the constant main effects with higher myristic, palmitic, and gondoic, but lower linolenic acid in the liver and yolk of COBB compared to the levels in those of ACRB. Finally, fat accumulation in the liver had no obvious difference between the breeds but was higher when embryo was older. In conclusion, broiler breed affects egg, embryo, and tissue weight, as well as FA composition in initial egg yolk and throughout the embryonic development. The highest docosahexaenoic percentage was observed in ACRB, indicating that genetic selection may result in fatty acid profile changes such as lower DHA content in chicken tissues and eggs.

Developmental changes in lipid and fatty acid metabolism and the inhibition by in ovo feeding oleic acid in Muscovy duck embryogenesis

“…Parallel changes in FA composition were found between the liver and serum in the current study. As the incubation proceeded, hepatic and serum UFA increased and SFA decreased, which was consistent with the FA changes reported in chicken and turkey embryos ( Ding and Lilburn, 1996 ; Su et al., 2020 ). In contrast to the FA composition of the liver or serum, that of the yolk sac stayed constant throughout embryogenesis, especially distinguished by a steady level of PUFA.…”

“…Furthermore, the egg yolk is the sole source of n-6 and n-3 polyunsaturated FA (PUFA) in the chick embryo due to the absence of desaturases that insert double bonds beyond the δ-9 carbon ( Cherian, 2015 ). Oleic acid (OA) is the most abundant FA in the yolk of developing chick embryos, which is key for energy supply during incubation ( Şahan et al., 2014 ; Su et al., 2020 ). We hypothesized that IOF-OA could achieve a beneficial effect on embryonic development by altering FA profile and lipid metabolism and modifying the regulation of transcription of different genes.…”

Study on the effect of different types of sugar on lipid deposition in goose fatty liver

“…According to the methods described as previous experiment ( Su et al., 2020 ). After grinding, 0.5 g liver sample was used to mix with 0.5 mL 0.5 g/l internal standard undecylenic acid methyl ester (Sigma), 2 mL 95% ethanol, 2 mL pure water and 0.1 g pyrogallic acid in a 50-mL screw-thread erlenmeyer flask, and then 10 mL HCL (8.3 mol/l) were added using water bath heating hydrolyzed the liver sample (80°C, 40 min).…”

Supplementing cholamine to diet lowers laying rate by promoting liver fat deposition and altering intestinal microflora in laying hens

“…It has been reported that during adipocyte formation (in utero and early infancy), exposure of animals to excessive n−6 fatty acids may promote fat deposition early in life ( Gibson et al, 2011 ). The n−6 to n−3 PUFA ratio is also associated with obesity in animals ( Su et al, 2020 ). In addition, many studies have shown that obesity and obesity-related diseases such as nonalcoholic fatty liver disease ( NAFLD ) are closely associated with a decrease in the biodiversity of intestinal microflora ( Arslan, 2014 ; Panasevich et al, 2016 ), and this association is also present in this study, that is, a reduction in the ɑ-biodiversity of intestinal microflora due to supplemented cholamine was associated with an increase in liver fat.…”