Heat challenge influences serum metabolites concentrations and liver lipid metabolism in Japanese quail (Coturnix japonica)

Alterations in the uterine echotexture, hemodynamics, and histological findings in relation to metabolomic profiles in goats with different ovarian activities (active versus inactive ovaries)

This study investigated, for the first time, the alterations in the uterine echotexture and blood flow in cyclic and acyclic (inactive ovary) goats using ultrasonography. The study aimed also to evaluate the metabolomic changes in the plasma of cyclic and acyclic goats. Furthermore, the histopathological approach was applied to the specimens of the uterus to validate the findings of this study. Based on monitoring the estrous cyclicity, goats were assigned into either a cyclic group or an acyclic one (n = 7, each). Ovarian morphometry and hemodynamics were assessed to confirm group assignment. Full ultrasonographic examinations were performed to assess the uterine echotexture by B-mode ultrasonography and uterine hemodynamics by color Doppler ultrasonography in the cyclic group (at days 10-12) and acyclic group. Additionally, blood samples were withdrawn for measuring hormonal concentrations and for metabolomics analysis. Specimens of the uterus were executed for histopathological evaluation in both groups. Results revealed alterations in the uterine hemodynamics and endometrial echotexture. Goats in the cyclic group attained a significantly higher color pixel area of the endometrium compared to those in the acyclic one (P< 0.001). However, the pixel intensity of the endometrium echotexture was significantly (P< 0.05) lower in the cyclic group than in the smooth inactive ovary one. There were significant (P< 0.05) increases in the concentrations of FSH, LH, and inhibin in the cyclic group compared to their concentrations in the acyclic one. Goats in the acyclic group attained noticeable (P< 0.001) lower concentrations of E2 and P4 than in the cyclic goats. The metabolomic results revealed the existence of several up- and down-regulated metabolites among the studied groups. In this investigation, untargeted metabolomic analysis revealed the existence of 5 up-regulated metabolites (ketoleucine, L-fucose, D-glucurono-6,3-lactone, melatonin, and 5-methoxy tryptamine) and 5 down-regulated ones (p-octopamine, 3-hydroxyisovaleric acid, methylmalonic acid, 4-hydroxyphenylpyruvic acid, and cadaverine) in the cyclic group compared to the acyclic one. The enrichment analysis of the significant metabolites showed top pathways that may be involved in these changes, such as fructose and mannose metabolism, valine. Leucine, and isoleucine biosynthesis, linoleic acid metabolism, arginine biosynthesis, and vitamin B6 metabolism based on the KEGG enriched pathway. Altogether, the histopathological assessment showed noticeable changes in the columnar epithelial lining of the endometrial epithelium, endometrial vascularity, and endometrial glands among the studied groups. In conclusion, this study extrapolated the differences between cyclic goats (during the mid-luteal phase) and acyclic ones in terms of hormonal, hemodynamics, echotexture of the uterus, and circulating metabolomics. These findings are very crucial to fully assess the fertility potential in goats.

Advance in the application of metabolomics technology in poultry

Metabolomics is a science that takes small molecular metabolites in organisms as the research object and determines the dynamic changes of metabolites at the overall level through a variety of modern analytical techniques. At present, metabolomics technology has been widely used in biological significance interpretation, food safety and quality, breeding, disease diagnosis, functional compound identification, and other fields. Its application in poultry science has also become the focus of widespread attention. With the sustainable development of analytical techniques, metabolomics has great potential in the application of poultry science. In this paper, the research progress of metabolomics in poultry growth and development, genetics and breeding, egg quality, meat quality, and disease is reviewed and concluded, which is expected to provide scientific ideas for the research of metabolomics in poultry.

Mechanisms underlying reproductive responses of Japanese quails to heat stress conditions

Exposure to heat stress can cause a significant increase in the death rate and disease susceptibility of poultry birds, ultimately impacting the profitability of the poultry industry. Despite being a more economical choice, Japanese quails (Coturnix japonica) are not immune to the harmful effects of heat stress. Quails may experience negative effects on their reproductive performance due to excessive reactive molecules caused by heat stress. However, they have developed various mechanisms to maintain their reproductive abilities in such conditions. The neuroendocrine system in birds plays a vital role in regulating their reproductive responses to thermal stress, and it is also connected to other environmental factors such as photoperiod that can impact their reproductive performance. Hormones are crucial in the complex interactions necessary for sexual maturation and reproductive responses to heat stress in Japanese quails living in stressful thermal conditions.

Effect of Acute Melatonin Injection on Metabolomic and Testicular Artery Hemodynamic Changes and Circulating Hormones in Shiba Goats under Sub-Tropical Environmental Conditions

The beneficial effects of melatonin were investigated to mitigate various detrimental effects and toxicity on reproductive performance. The present study aimed, for the first time, to explore the effect of intravenous melatonin injection on testicular artery hemodynamics (TH) and metabolomic changes, reproductive hormones in heat-stressed bucks. Ten bucks were randomly split into two groups (five each): (1) the melatonin group, treated with a single intravenous dose of melatonin solution containing 10 mg melatonin each, and (2) the control group, which was treated with 10 mL of the vehicle without melatonin. Changes in the TH at the level of the supra testicular artery (STA) were assessed by triplex ultrasonography just before (0 h) and at 0.5, 2, 7, 24, and 168 h after melatonin or vehicle administration. Doppler velocity parameters of peak systolic velocity (PSV; cm/s), end-diastolic velocity (EDV; cm/s), and time average maximum velocity (TAMAX; cm/s) were measured. Doppler indices (resistive index; RI and pulsatility index; PI), systole/diastole (S/D) ratio and total arterial blood flow volume (TABFV; ml/minute) were measured. Peripheral concentrations of FSH, LH, inhibin, melatonin, testosterone (T), estradiol (E2), and cortisol were measured just before injection (0 h) and at 0.5, 2, 7, and 24 h and daily up to day 7 post administration in both groups. Results revealed reductions in the RI values and increases in the TABFV in the melatonin group compared to the control one, especially 2 h after administration. Significant increases in concentrations of FSH, T, E2, and melatonin and decreases in cortisol and inhibin in the melatonin group compared to the control one. Plasma metabolomic analysis at 2 h indicated the up-regulation of L-glutamine, L-arginine, sorbitol, D-glucose, ascorbic acid, and ornithine and the down-regulation of D-xylose, D-arabitol, ribitol, and oleic acid in the melatonin versus the control group. In conclusion, acute administration of melatonin (10 mg IV) enhanced testicular artery blood flow and plasma reproductive hormones in the Shiba goat under heat-stress circumstances.

Characterization of Serum Metabolome and Proteome Profiles Identifies SNX5 Specific for Pregnancy Failure in Holstein Heifers

Pregnancy loss predominantly occurs during the first 3–4 weeks due to fertilization failure or early embryonic losses in cattle. Insufficient biochemical communication between conceptus (embryo plus extraembryonic membranes) and endometrium has been suspected as the primary cause for early embryonic losses. If molecules regulating this communication were identified, molecular mechanisms associated with early pregnancy losses could be better understood. To identify candidate molecules as detection markers of non-pregnant or females undergoing embryonic loss, peripheral blood from embryo-transferred heifers on day 7 (day 0 = day of estrus) were collected on days 17 (pre-attachment), 20 (during attachment), and 22 (post-attachment), which were subjected to metabolome and global proteome iTRAQ analyses. The metabolome analysis partly divided serum components into pregnant or not. In the iTRAQ analysis, heatmap analysis with top 25 proteins was separated into pregnant or not on day 20 or 22. Furthermore, receiver operating characteristic curve (ROC) analysis identified five candidate proteins detecting non-pregnant heifers, of which SNX5 in day 22 serum had the highest area under the curve (AUC): 0.983. We also detected SNX5 in day 22 serum from non-pregnant heifers using western blotting. These results suggest that high SNX5 in day 22 serum could predict early pregnancy loss in heifers.