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Simple Summary: Heat stress is a challenging environmental factor that affects poultry production. Adaptation to heat stress is regulated by heat shock proteins (HSPs). In chickens, HSP70 expression is controlled by heat shock factor 3 (HSF3). The genetic diversity of heat shock genes is thought to be closely associated with the productive and reproductive performance of farm animals. The present study aimed to explore the relationships between single-nucleotide polymorphisms (SNPs) in the genes of Bangladeshi hilly chickens and their egg production traits. Sequencing and allele-specific PCR identified two novel SNPs (G-399A and A-68G) in the 5′-flanking regions of HSP70. In addition, three previously identified SNPs in HSP70 (A258G, C276G and C1431A) and two SNPs in HSF3 (A-1388G and A-1703G) were also genotyped. A population of 150 breeding hilly chickens was used to analyze the associations between SNPs in these genes and the chickens' egg production traits. Among the analyzed SNPs, the two novel SNPs (G-399A and A-68G) were significantly associated with egg number and egg weight, respectively. In addition, all other SNPs except A-1703G were also found to be associated with egg production traits. These results suggest that the identified SNPs in these genes might be useful in a selective breeding program to enhance productivity in warm environments. In warm environments, thermoregulation in poultry is controlled by heat shock protein 70 (HSP70), whose expression is controlled by heat shock factor 3 (HSF3). Although the association between genetic polymorphisms in these genes and thermotolerance as well as reproductive traits has been extensively studied in mammals, the association has not yet been studied in poultry. This study aimed to explore the relationship between single-nucleotide polymorphisms (SNPs) in these genes and the egg production traits of Bangladeshi hilly chickens. Sequencing and allele-specific PCR (AS-PCR) were used to detect new SNPs and perform genotyping. We identified two novel SNPs (G-399A and A-68G) in the 5′-flanking regions of HSP70 that were significantly associated with egg numbers (ENs) at 161–190 days and increased egg weight (EW) at 40 weeks of age. Furthermore, three SNPs in HSP70 (A258G, C276G and C1431A) and one SNP in HSF3 (A-1388G) were associated with EN at different ages. The haplotype and combined genotypic effects of these two genes were found to be associated with age at sexual maturity (ASM), EN, EW, and body weight at ASM. The identified SNPs and their corresponding haplotypes may be useful in selective breeding to enhance the productivity of chickens in warm environments. [ABSTRACT FROM AUTHOR] more...

Stress and anxiety are significant psychological challenges in modern society, which have led to a rapidly growing market for functional foods, including those reported to relieve stress, as alternatives to psychoactive drugs. Among these, diacyl glyceryl ethers (DAGE) derived from deep-sea shark liver oil have gained attention for their strong antioxidant properties and potential mental health benefits. Building on preliminary evidence suggesting DAGE's efficacy in enhancing stress resilience and modulating biochemical pathways associated with reduced oxidative stress, the present study aimed to examine their effects on stress responses in two specific mouse strains. Each mouse was fed either a DAGE-infused diet or a control diet for three weeks. Their stress responses were evaluated using three behavioral tests: the elevated plus maze, open-field, and forced swimming tests. The DAGE-fed mice displayed lower stress responses than the control mice in the initial trial of each test. Specifically, DAGE-fed mice demonstrated increased time spent in the open arms in the elevated plus maze and more time spent in the center of the open field, suggesting reduced anxiety. Additionally, in the forced swimming test, DAGE-treated mice displayed reduced immobility times, indicating potential antidepressant effects on the mice. These findings suggest the potential of DAGE to bolster stress resilience in mice, emphasizing their promise for further studies in human stress management. [ABSTRACT FROM AUTHOR] more...

The spontaneously hypertensive rat (SHR) is a model of cardiomyopathy that displays a genetic defect in cardiac fatty acid (FA) translocase/CD36, a plasma membrane long-chain FA transporter. Therapy with medium-chain FAs, which do not require CD36-facilitated transport, has been shown to improve cardiac function and hypertrophy in SHRs despite persistent hypertension. However, little is known about the underlying molecular mechanisms. The aim of this study was to document the impact of medium-chain triglyceride (MCT) therapy in SHRs on the expression level and activity of metabolic enzymes and signaling pathways. Four-week-old male SHRs were administered MCT (SHR-MCT) or long-chain triglyceride (SHR-LCT) for 16 wk. We used Wistar-Kyoto (WKY) rats as controls (WKY-MCT and WKY-LCT). The SHR-MCT group displayed improved cardiac dysfunction [as assessed by left ventricular (LV) end-diastolic pressure and the positive and negative first derivatives of LV pressure/P value], a shift in the [beta]-myosin heavy chain (MHC)-to-[alpha]-MHC ratio, and cardiac hypertrophy compared with the SHR-LCT group without an effect on blood pressure. Administration of MCT of SHRs reversed the LCT-induced reduction in the cardiac FA metabolic enzymatic activities of longchain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) and mediumchain acyl-CoA dehydrogenase (MCAD). In the SHR-MCT group, the protein expression and transcriptional regulation of myocardial peroxisome proliferator-activated receptor-[alpha], which regulates the transcription of LCHAD and MCAD genes, corresponded to the changes seen in those enzymatic activities. Furthermore, MCT intake caused an inhibition of JNK activation in SHR hearts. Collectively, the observed changes in the myocardial activity of metabolic enzymes and signaling pathways may contribute to the improved cardiac dysfunction and hypertrophy in SHRs following MCT therapy. peroxisome proliferator-activated receptor-s; CD36; c-Jun N[H.sub.2]-terminal kinase; myosin heavy chain; spontaneously hypertensive rats more...