Long-term fasting induced basal thermogenesis flexibility in female Japanese quails.

Male Japanese quails (Coturnix japonica) have been found to exhibit a three-phase metabolic change when subjected to prolonged fasting, during which basal thermogenesis is significantly reduced. A study had shown that there is a significant difference in the body temperature between male and female Japanese quails. However, whether female Japanese quails also show the same characteristic three-phase metabolic change during prolonged fasting and the underlying thermogenesis mechanisms associated with such changes are still unclear. In this study, female Japanese quails were subjected to prolonged starvation, and the body mass, basal metabolic rate (BMR), body temperature, mass of tissues and organs, body fat content, the state-4 respiration (S4R) and cytochrome c oxidase (CCO) activity in the muscle and liver of these birds were measured to determine the status of metabolic changes triggered by the starvation. In addition, the levels of glucose, triglyceride (TG) and uric acid, and thyroid hormones (T3 and T4) in the serum and the mRNA levels of myostatin (MSTN) and avian uncoupling protein (av-UCP) in the muscle were also measured. The results revealed the existence of a three-phase stage similar to that found in male Japanese quails undergoing prolonged starvation. Fasting resulted in significantly lower body mass, BMR, body temperature, tissues masses and most organs masses, as well as S4R and CCO activity in the muscle and liver. The mRNA level of av-UCP decreased during fasting, while that of MSTN increased but only during Phase I and II and decreased significantly during Phase III. Fasting also significantly lowered the T3 level and the ratio of T3/T4 in the serum. These results indicated that female Japanese quails showed an adaptive response in basal thermogenesis at multiple hierarchical levels, from organismal to biochemical, enzyme and cellular level, gene and endocrine levels and this integrated adjustment could be a part of the adaptation used by female quails to survive long-term fasting.

Dendrobium officinale polysaccharide alleviates thiacloprid-induced kidney injury in quails via activating the Nrf2/HO-1 pathway.

Thiacloprid (THI) is a neonicotinoid insecticide, and its wide-ranging use has contributed to severe environmental and health problems. Dendrobium officinale polysaccharide (DOP) possesses multiple biological activities such as antioxidant and antiapoptosis effect. Although present research has shown that THI causes kidney injury, the exact molecular mechanism and treatment of THI-induced kidney injury remain unclear. The study aimed to investigate if DOP could alleviate THI-induced kidney injury and identify the potential molecular mechanism in quails. In this study, Japanese quails received DOP (200 mg/kg) daily with or without THI (4 mg/kg) exposure for 42 days. Our results showed that DOP improved hematological changes, biochemical indexes, and nephric histopathological changes induced by THI. Meanwhile, THI exposure caused oxidative stress, apoptosis, and autophagy. Furthermore, THI and DOP cotreatment significantly activated the nuclear factor erythroid 2-related factor 2/heme oxygenase-1 (Nrf2/HO-1) pathway, restored antioxidant enzyme activity, and reduced apoptosis and autophagy in quail kidneys. In summary, our study demonstrated that DOP mitigated THI-mediated kidney injury was associated with oxidative stress, apoptosis, and autophagy via activation of the Nrf2/HO-1 signaling pathway in quails.

The role of chamomile oil against ochratoxin A in quail breeders: productive and reproductive performances, egg quality, and blood metabolites.

This study aimed to evaluate the beneficial role of chamomile essential oil in improving productive and reproductive performances, egg quality, and blood metabolites and reducing the toxic effect of Ochratoxin A (OTA) in quail breeder's diets. A total of 144 mature quails, 8 wk old, were divided into 6 groups. The treatments were: G1 (the control), G2 (supplemented with OTA 1 mg/kg diet), G3 (supplemented with chamomile oil 0.5 g/kg diet), G4 (supplemented with chamomile oil 1 G/kg diet), G5 (supplemented with OTA 1 mg/kg diet + chamomile oil 0.5 g/kg diet), and G6 (supplemented with OTA 1 mg/kg diet + chamomile oil 1 g/kg diet). The OTA administration alone significantly decreased egg production and mass in quail breeders (P < 0.0001). Moreover, poor feed conversion ratio (FCR), fertility percentage (P < 0.0001), and hatchability percentage (P < 0.0009) were recorded. A significant decline (P < 0.05) in the levels of serum protein (total protein and globulin) was also recorded in OTA-contaminated groups, along with elevated serum levels of liver enzymes such as alanine transaminase (ALT) and Aspartate transaminase (AST) and kidney function test as urea and creatinine levels (P < 0.05). Ochratoxin A-contaminated feed resulted in a significant elevation (P < 0.05) in total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL), and very low-density lipoprotein (VLDL), along with a significant reduction (P < 0.05) in antioxidant status and immunological response. The supplementation of chamomile essential oil, either 0.5 g/kg or 1g/kg, to the basal diet or OTA-supplemented feed, revealed a significant increase in hatchability %, fertility, egg mass, and egg production and better FCR, egg quality, and immunological status when compared to OTA only. Moreover, chamomile essential oil supplementation improves liver and kidney function markers, decreases LDL, VLDL), TG, and TC. Along with a significant increase (P < 0.05) in terms of antioxidant status as glutathione peroxidase enzyme (GPX), total antioxidant capacity (TAC), and superoxide dismutase (SOD) and significantly (P < 0.05) improves immunological response as IgM, IgG, lysozyme and complement 3. In summary, chamomile oil supplementation, either separate or combined with OTA, reduced the adverse effects of OTA and led to improved productive and reproductive performance, egg quality, and blood metabolites in Japanese quail breeders.

Yucca schidigera Extract Mitigates the Oxidative Damages, Inflammation, and Neurochemical Impairments in the Brains of Quails Exposed to Lead.

The present study explored the neurotoxic impacts of lead (Pb) and the potential alleviating effect of Yucca schidigera extract (YSE) in Japanese quails. About 360 adult Japanese quails (8 weeks old) were used. Quails were randomly distributed to six groups with 4 replicates each: the control group (fed basal diet, BD), the BD + YSE1 and BD + YSE2 groups (BD + 100 and 200 mg/kg diet of YSE, respectively), the Pb group (BD + 100 mg/kg Pb), and the Pb + YSE1 and Pb + YSE2 groups (BD + Pb + 100 and 200 mg/kg YSE, respectively). This feeding trial lasted for 8 weeks. The exposure to Pb in the diet induced oxidative damage stress in the brain of exposed quails reflected by the significant increase in the oxidative markers including malonaldehyde (MDA) and protein carbonyl (PC) and the significant reduction in the activities of antioxidants including catalase (CAT), superoxide dismutase (SOD), and the reduced glutathione (GSH). Brain neurochemistry and enzyme activities were also altered following Pb exposure. Pb significantly reduced serotonin, dopamine, norepinephrine, GABA, Ach, and Na + /K + -ATPase activities. Pb dietary intoxication markedly increased brain inflammatory biomarkers, including tumor necrosis factor (TNF-α), myeloperoxidase, and nitric oxide. Peripherally, Pb toxicity decreased the amino acid neurotransmitters (glutamic acid, glycine, and aspartic acid) in the serum of birds. At the transcriptomic level, Pb exposure upregulated the transcription patterns of CASP3, TNF-α, HSP70, and IL-1ß. The single effect of YSE maintained that all the assessed parameters were not changed compared to the control. Interestingly, the YSE co-supplementation with Pb alleviated the Pb-induced neuro-oxidative damages by lowering the lipid, protein, and DNA damage, and the inflammatory biomarkers.

The ROS/SIRT1/STAR axis as a target for melatonin ameliorating atrazine-induced mitochondrial dysfunction and steroid disorders in granulosa cells.

The granulosa cells (GCs) of birds are essential for the reproduction and maintenance of populations in nature. Atrazine (ATR) is a potent endocrine disruptor that can interfere with reproductive function in females and Diaminochlorotriazine (DACT) is the primary metabolite of ATR in the organism. Melatonin (MT) is an endogenous hormone with antioxidant properties that plays a crucial role in development of animal germ cells. However, how ATR causes mitochondrial dysfunction, abnormal secretion of steroid hormones, and whether MT prevents ATR-induced female reproductive toxicity remains unclear. Thus, the purpose of this study is to investigate the protective effect of MT against ATR-induced female reproduction. In the present study, the GCs of quail were divided into 6 groups, as follows: C (Serum-free medium), MT (10 µM MT), A250 (250 µM ATR), MA250 (10 µM MT+250 µM ATR), D200 (200 µM DACT) and MD200 (10 µM MT+200 µM DACT), and were cultured for 24 h. The results revealed that ATR prevented GCs proliferation and decreased cell differentiation. ATR caused oxidative damage and mitochondrial dysfunction, leading to disruption of steroid synthesis, which posed a severe risk to GC's function. However, MT supplements reversed these changes. Mechanistically, our study exhibited that the ROS/SIRT1/STAR axis as a target for MT to ameliorate ATR-induced mitochondrial dysfunction and steroid disorders in GCs, which provides new insights into the role of MT in ATR-induced reproductive capacity and species conservation in birds.

Consequences of dietary cinnamon and ginger oils supplementation on blood biochemical parameters, oxidative status, and tissue histomorphology of growing Japanese quails.

The present study aimed to investigate the impact of various concentrations of ginger and cinnamon oils as antibiotic substitutes on some blood biochemical parameters, antioxidant capacity, and histopathological profile of the liver and gut of growing Japanese. A total of 900 Japanese quails were randomly allotted into 6 treatment groups. Each group had 5 replicates (30 chicks each). The first group received a basal diet and served as the control, while the second received a basal diet plus 0.5 g of colistin antibiotic/kg diet. The third and fourth groups were supplemented with 0.5 mL and 1.0 mL of ginger oil (GO)/kg diet, respectively. While the fifth and sixth groups received basal diet with 0.5 and 1.0 mL of cinnamon oil (CO)/kg diet, respectively. Results showed that adding herbal oils significantly (P < 0.05) decreased the aspartate aminotransferase (AST) and urea levels compared to control and colistin groups. Various levels of GO and CO significantly (P < 0.05) reduced cholesterol levels compared to control birds. Compared to the control and antibiotic groups, Japanese quails supplemented with various levels of herbal oils (GO and CO) had more extraordinarily significant (P < 0.05) values for total antioxidant capacity (TAC), superoxide dismutase (SOD), glutathione peroxidase (GPX), and glutathione reductase (GSR). Regarding histopathologic examination, the jejunum displayed a nearly empty lumen, a few fusions, and mild goblet cell metaplasia. On the other hand, the duodenum looked tall and had a few fusions of villi and remnants of removal in its lumina. It could be concluded that cinnamon and GO improved birds' blood biochemical parameters, electorate oxidative stress, and enhanced intestinal and hepatic histology of the treated quails. Also, the levels of 0.5 mL CO and 0.5 mL GO may be an acceptable substitute for antibiotics (colistin) in the diets of growing Japanese quail.

Pheasant hatchability and physicochemical features of egg and extra-embryonic structures depending on eggshell color.

The study aimed to analyze the biological value of eggs and extra-embryonic structures affecting pheasant hatchability depending on the eggshell's color. Eggs (1,415) from 62-wk-old pheasants were used. The quality of fresh blue (BL), brown (BR), and green (G) eggs were analyzed. Incubation lasted for 25 d. Thick albumen (d 0, 1, 7, 14), amniotic fluid (d 14, 18), and the yolk (d 0-14) were collected. The pH, viscosity, lysozyme activity, crude protein (CP) content in albumen and amnion, pH, vitelline membrane strength, and fatty acids (FA) content in the yolk were performed. The lowest hatchability was in the BL group, and the highest was in the G group. BL group showed lower eggshell thickness and strength and higher egg weight. In thick albumen and amniotic fluid, the pH decreased with the incubation. In the yolk, there was an increasing trend (P = 0.015), with a decrease on d 18 (P < 0.001). The vitelline membrane strength decreased after 1 d of incubation, excluding BR eggs (P < 0.001). Thick albumen viscosity was higher on d 14 in the G group than in other dates and groups, the lowest in amniotic fluid, and slightly higher in BL and BR eggs. On d 18, amniotic fluid viscosity increased (P < 0.001). The lowest viscosity was indicated in BL eggs (P < 0.001). The lysozyme activity in thick albumen on d 14 was the highest (uniquely in BR and G groups), and the lowest values were found in amniotic fluid on d 14; after four d, the activity increased (P < 0.001). The CP content was higher in the BL group on d 14. In amnion, on d 14, the CP content was the lowest (<1%) and increased on d 18 (P < 0.001). There was a higher FA content (especially UFA) in the G group and a decrease in FA content after d 14 (P < 0.001). It was found that eggs with green eggshells have the highest biological value, and blue eggs are the least useful for incubation.

Effect of atrazine on testicular toxicity involves accommodative disorder of xenobiotic metabolizing enzymes system and testosterone synthesis in European quail (Coturnix coturnix).

Due to the wide use of atrazine (ATR), the concern has increased regarding the negative impact of ATR on reproduction. Nevertheless, the reproductive effects caused by different exposure concentrations and the severity of toxic damage are poorly understood. In organisms, ATR is metabolized and degraded through phase II enzyme systems, and changes in cytochrome P450 (CYP) enzymes may have a regulatory role in the harm of ATR. However, less information is available on the induction of CYPs by ATR in avian organisms, and even less on its effects on the testis. Birds are exposed to ATR mainly through food residues and contaminated water, the purpose of this study was to examine reproductive toxicity by different exposure concentrations and elaborate metabolic disorders caused by ATR in European quail (Coturnix coturnix). In this study, the quail were given ATR at 50 mg/kg, 250 mg/kg and 500 mg/kg by oral gavage for 45 days, and the testicular weight coefficients, histopathology and ultrastructure of testes, primary biochemical functions, sex steroid hormones, critical protein levels in the testosterone synthesis pathway, the expression of genes involved CYPs, gonad axis and nuclear receptors expression were investigated. Altogether, testicular coefficient decreased significantly in the high-dose group (1.22%) compared with the control group (3.03%) after 45 days of ATR exposure, and ATR is a potent CYP disruptor that acts through the NXRs and steroid receptor subfamily (APND, CAR, ERND and ERα) without a dose-dependent manner. Notably, ATR interfered with the homeostasis of hormones by triggering the expression of hormones on the gonad axis (LH and E2). These results suggest that exposure to ATR can cause testicular toxicity involving accommodative disorder of phase II enzyme and testosterone synthesis in European quail.

Does dietary linseed or canola oil affect lipid metabolism, immunity, and n-3 polyunsaturated fatty acids content in quail eggs?

One of the most intriguing areas of research and innovation in the animal production and food sector recently has been designed-enriched products. These items are regarded as functional foods because they feature components that have advantageous physiological impacts on human health. In the production of poultry, designed eggs constitute a significant category of functional foods. The present study hypothesized that adding different kinds of oils to quail diets will help produce designer eggs rich in omega-3 and 6 fatty acids in addition to enhancing productive performance. So, this study examined how linseed (flaxseed) and canola oils with various levels can affect lipid metabolism, immune function, and the amount of n-3 polyunsaturated fatty acids (n-3 PUFA) in Japanese quail eggs. This work was conducted using 3 different vegetable oils (sunflower, linseed, and canola oils) and 3 different antioxidant supplements (0, 250 mg vitamin E/kg feed, and 1,000 mg ginger/kg feed) in a 3 × 3 factorial experiment. When linseed or canola oil was added to the diet, the number of fatty acids in the egg yolks of Japanese quail layers fell by (12.7 and 18.9%) and (41.4 and 24.6%), respectively. The amounts of saturated and monounsaturated fatty acids in total eggs fell by 21.9 and 14.6% and 24.5 and 15.8%, respectively, at 20 wk of age. However, when linseed and canola oil were added to the diet, the sum n-3 PUFA content in the egg yolk of Japanese quail-laying hens was noticeably raised at 15 and 20 wk of age. At 15 and 20 wk of age, the same groups' total n-6 PUFA content considerably increased compared to the group that did not receive flaxseed. In conclusion, during the laying period of Japanese quail, linseed oil, canola oil, vitamin E, or ginger positively affected productivity, blood hematology, constituents, resistance, lipid digestion system, and antioxidative properties in serum and egg yolk.

Glucose oxidation drives trunk neural crest cell development and fate.

Bioenergetic metabolism is a key regulator of cellular function and signaling, but how it can instruct the behavior of cells and their fate during embryonic development remains largely unknown. Here, we investigated the role of glucose metabolism in the development of avian trunk neural crest cells (NCCs), a migratory stem cell population of the vertebrate embryo. We uncovered that trunk NCCs display glucose oxidation as a prominent metabolic phenotype, in contrast to what is seen for cranial NCCs, which instead rely on aerobic glycolysis. In addition, only one pathway downstream of glucose uptake is not sufficient for trunk NCC development. Indeed, glycolysis, mitochondrial respiration and the pentose phosphate pathway are all mobilized and integrated for the coordinated execution of diverse cellular programs, epithelial-to-mesenchymal transition, adhesion, locomotion, proliferation and differentiation, through regulation of specific gene expression. In the absence of glucose, the OXPHOS pathway fueled by pyruvate failed to promote trunk NCC adaptation to environmental stiffness, stemness maintenance and fate-decision making. These findings highlight the need for trunk NCCs to make the most of the glucose pathway potential to meet the high metabolic demands appropriate for their development.

Indicators of thermal comfort and nitrogen digestibility as a function of digestible arginine: lysine ratios in the diet of laying Japanese quails raised in hot weather.

The objective with this study was to determine the influence of the digestible arginine: lysine ratio in the diet of laying Japanese quails raised in hot weather on the physiological variables of thermoregulation, time in tonic immobility, behavior and nitrogen utilization. A total of 240 laying quails (Coturnix coturnix japonica) with 40 weeks of age were used in a completely randomized design with five treatments and six replications containing eight quails per experimental unit. The studied digestible arginine: lysine ratios were 110%; 120%, 130%, 140% and 150%, for 63 days divided into three periods of 21 days each. There was a quadratic effect (p < 0.05) for the variables average surface temperature, average body temperature, core to surface thermal gradient, ambient to surface temperature gradient observed in the morning. In the afternoon, a quadratic effect (p < 0.05) of the arginine: lysine ratio was observed for variables average surface temperature, average body temperature, core to surface thermal gradient, ambient to surface thermal gradient, back temperature, head temperature and respiratory frequency. There was no significant effect (p > 0.05) of arginine: lysine ratios on the frequency of behaviors, except drinking and panting (p < 0.05), for which 130% ratio provided the lowest frequencies of these behaviors. There was a quadratic effect (p < 0.05) for the parameters of nitrogen retention, nitrogen excreted and nitrogen retention efficiency. Nitrogen intake and excreta moisture were not influenced by the different relationships studied (p > 0.05). The 130% arginine: lysine ratio corresponding to 0.131 g/kg/feed of arginine improves physiological responses related to thermoregulation and decreases the expression of behaviors correlated to heat stress, also meeting the best estimated ratio for nitrogen retention in the diet of quails laying Japanese raised in hot weather.

Hormonal regulation of visfatin and adiponectin system in quail muscle cells.

Visfatin and adiponectin are two adipokines known to regulate energy homeostasis and stress response within different peripheral tissues. Their role and regulation in highly metabolically active tissue such as the muscle is of particular interest. As modern poultry exhibit insulin resistance, obesity, and hyperglycemia along with a lack of insight into the regulation of these avian adipokines, we undertook the present work to determine the regulation of visfatin and adiponectin system by cytokines and obesity-related hormones in a relevant in vitro model of avian muscle, quail muscle (QM7) cells. Cells were treated with pro-inflammatory cytokine IL-6 (5 and 10 ng/mL) and TNFα (5 and 10 ng/mL), as well as leptin (10 and 100 ng/mL) and both orexin-A and orexin-B (ORX-A/B) (5 and 10 ng/mL). Results showed significant increases in visfatin mRNA abundance under both cytokines (IL-6 and TNFα), and down regulation with ORX-B treatment. Adiponectin expression was also upregulated by pro-inflammatory cytokines (IL-6 and TNFα), but down regulated by leptin, ORX-A, and ORXB. High doses of IL-6 and TNFα up regulated the expression of adiponectin receptors AdipoR1 and AdipoR2, respectively. Leptin and orexin treatments also down regulated both AdipoR1 and AdipoR2 expression. Taken together, this is the first report showing a direct response of visfatin and the adiponectin system to pro-inflammatory and obesity-related hormones in avian muscle cells.

Endocrine and molecular regulation mechanisms of follicular development and egg-laying in quails under different photoperiods.

Photoperiod is a key environmental factor in regulating bird reproduction and induces neuroendocrine changes through the hypothalamic-pituitary-gonadal (HPG) axis. OPN5, as a deep-brain photoreceptor, transmits light signals to regulate follicular development through TSH-DIO2/DIO3. However, the mechanism among OPN5, TSH-DIO2/DIO3, and VIP/PRL in the HPG axis underlying the photoperiodic regulation of bird reproduction is unclear. In this study, 72 laying quails with 8-week-old were randomly divided into the long-day (LD) group [16 light (L): 8 dark (D)] and the short-day (SD) group (8 L:16 D), and then samples were collected on d 1, d 11, d 22, and d 36 of the experiment. The results showed that compared with the LD group, the SD group significantly inhibited follicular development (P < 0.05), decreased the P4, E2, LH, and PRL in serum (P < 0.05), downregulated the expression of GnRHR, VIP, PRL, OPN5, DIO2, and LHß (P < 0.05), reduced the expression of GnRH and TSHß (P > 0.05), and promoted DIO3, GnIH gene expression (P < 0.01). The short photoperiod downregulates OPN5, TSHß, and DIO2 and upregulates DIO3 expression to regulate the GnRH/GnIH system. The downregulation of GnRHR and upregulation of GnIH resulted in a decrease in LH secretion, which withdrew the gonadotropic effects on ovarian follicles development. Slow down of follicular development and egg laying may also arise from lack of PRL potentiation to small follicle development under short days.

Effect of dietary supplementation of Spirulina platensis powder on performance, some serum biochemistry, digestive enzymes, microbial content, antioxidant parameters and immune responses of growing Japanese quail.

This study was performed to examine the influences of Spirulina platensis powder (SPP) on growth performance, physiological status, blood biochemistry, and intestinal microbial population in quail. 240-10-days old Japanese quail chicks were distributed into five groups. Each group had four replicate pens with 12 birds each. The first group received a basal diet (control group). Groups from two to five received the basal diet with SPP at levels of 1.5, 3.0, 4.5, and 6.0% as dietary ingredients, respectively. Results clarified significantly higher live body weight and body weight gain (p < 0.001) with significant enhancements (p < 0.001) in feed conversion values for groups that received SPP levels, especially 4.5% compared with the control and other groups. Birds fed on a diet containing SPP had significantly higher amylase, trypsin and lipase levels (p < 0.001) than the control. Intestinal Lactobacillus sp. was significantly increased, and Escherichia coli and Salamonella populations were significantly decreased by dietary SPP levels (p < 0.001). Liver function, total lipid profile, antioxidant parameters and immune response were significantly affected by SPP levels compared with the control (p < 0.001). In conclusion, the inclusion of SPP until 4.5% in quail diets could improve the growth performance, intestinal microbial population and serum biochemical constituents of growing quail.

Productive performance, lipid profile, immunity, and antioxidant parameters of quail breeders fed low protein diets supplemented with different zinc sources.

The current study was conducted to study the impact of low-CP protein diets with different sources of zinc (zinc oxide-ZnO and zinc methionine-Zn-Met) on performance, lipid profile, immune and antioxidant parameters of quail breeders. A total number of 216 Japanese quail at 8 weeks of age were randomly distributed into nine (3 × 3) groups, with four replicates, each of six quails (four females and two males). Quails were fed three levels of CP (16, 18, and 20%) and three sources of Zn (0, 0.1 g ZnO, and 0.1 g Zn-Met/kg diets). No significant differences in daily feed intake (FI), feed conversion ratio (FCR), and egg mass are due to the main effect of protein levels or zinc sources at all ages. Dietary CP (16 and 20%) in growing quail diets increased SOD and GSH, while IgG levels were improved by 18%. Finally, it can be recommended that 16% CP and zinc source (Zn-Met or ZnO) can maintain egg mass, as well as lipid profile, immunological and antioxidant parameters in Japanese quails breeders. This level (16% CP) is enough during the production stage and a valuable way for mitigating ammonia pollution and reducing feeding costs.

Apparent and standardized ileal amino acid digestibilities of corn, wheat, soybean meal, and corn gluten meal in quail chicks.

Two experiments were conducted to measure the apparent and standardized ileal digestibilities (AID and SID) of amino acid (AA) of corn, wheat, soybean meal (SBM), and corn gluten meal (CGM) in growing Japanese quail from 14 to 18 (Exp. 1) and 28 to 32 (Exp. 2) d of age. The basal endogenous losses of amino acids were measured by the use of N-free diet. The birds were fed on standard diet before the use of experimental diets. The experimental diets (four ingredients) and N-free diet were randomly assigned to 5 replicate pens (30 birds per pen) and fed for 5 consecutive days. The ileal digesta were collected on d 18 and 32 for the Exp. 1 and Exp. 2, respectively. AID of lysine (Lys) in corn (P = 0.047), SBM (P < 0.001), and CGM (P < 0.001); AID of threonine (Thr) in corn (P < 0.001), SBM (P < 0.001), and CGM (P = 0.075); and AID of isoleucine (Ile) in wheat (P < 0.001), SBM (P = 0.002), and CGM (P < 0.001) were increased as the birds aged. However, AID of methionine (Met) in corn (P < 0.001) and CGM (P < 0.001), AID of arginine (Arg; P < 0.001) and valine (Val; P < 0.001) in CGM were lower in younger quails. Among indispensable amino acids, the basal endogenous losses of Thr, Val, and Arg decreased by age (P < 0.001). The average of SID of Lys, Ile, Met, Val, Thr, Arg, leucine (Leu), and histidine (His) for corn, wheat, SBM, and CGM were estimated as 83, ND, 89.4, 89.4, 92.1, 90.2, 91.9, and 90.8%; 92.7, ND, 89.1, 93.9, 87.4, 90.2, 89.8, and 88.1%; 90.3, 91.8, 94.3, 90.4, 86.5, 94.0, 84.3, and 95.0%; 82.6, ND, 74.1, 79.6, 84.4, 90.6, 85.2, and 82.4%, respectively. Based on the present study, the AID and SID coefficients of indispensable AA should be adjusted for age classes in Japanese quail during the growing period.

Effects of melittin on laying performance and intestinal barrier function of quails.

To study the effects of melittin on egg-laying performance and intestinal barrier of quails, 240 quails (aged 70 d) were randomly divided into 4 groups with 6 replicates (10 quails per replicate). They were fed with basal diet (group B), basal diet + 0.08 g/kg melittin (group BA1), basal diet + 0.12 g/kg melittin (group BA2) and basal diet + 0.16 g/kg melittin (group BA3). The experiment lasted for 21 days. The eggs were collected every day. At the end of the experiment, duodenal, jejunal, and ileal tissues were collected, and the cecal contents were sampled. Intestinal antioxidant index, barrier function, and intestinal flora were analyzed. The results showed that the addition of melittin significantly increased the laying rate and average egg weight. Addition of melittin significantly increased the antioxidant function, mechanical barrier, immune barrier, and the villus height to crypt depth ratio of small intestine. Addition of melittin had no significant effect on the α and ß diversity of cecal flora, but significantly increased the abundance of Bacteroidales at family level and genus level. Bioinformatics analysis of cecal content showed significant increase in COG functional category of cytoskeleton, and significant decrease in RNA processing and modification in group BA2. KEGG functional analysis showed significant decrease in steroid biosynthesis, caffeine metabolism, and cytochrome P450 pathways in group BA2. In conclusion, addition of 0.12 g/kg melittin to feed improved the laying performance and the intestinal antioxidant capacity and barrier function of quails but had no significant effect on the composition and structure of cecal microbial community. This study provides experimental data and theoretical basis for the application of melittin as a new quail feed additive.

Overnutrition-induced gout: An immune response to NLRP3 inflammasome dysregulation by XOD activity increased in quail.

Background: Gout is a progressive metabolic disease closely related to hyperuricemia and urate deposition, with an increasing prevalence and incidence across the globe. Recent studies have shown that the pathological process of gout includes two stages: asymptomatic hyperuricemia and MSU crystal deposition. However, the immune response during the development of hyperuricemia to gouty arthritis is not fully elucidated. Methods: Thus, an overnutrition-induced whole-course gout model was established to clarify the immune response and pathological changes in the development from hyperuricemia to gouty arthritis. The quails without urate oxidase were used as experimental animals. And we confirmed that uric acid metabolic targets were changed when quails were in the asymptomatic hyperuricemia stage. Results: When the quail showed gout symptoms, the NLRP3 inflammasome was activated, and the expressions of IL-1ß, TNF-α, IL-6, IL-8, and IL-18 were significantly increased. The relationship between the uric acid metabolism target and the NLRP3 inflammasome may be the critical immune response between hyperuricemia and gouty arthritis. Our data showed that, in the process of gout disease, the expression of xanthine oxidase (XOD) has been increasing, which increases the level of uric acid, disrupts the balance of oxidative stress, generates a large amount of ROS, activates the NLRP3 inflammasome, and release IL-1ß. Treatment with the XOD inhibitor can reduce uric acid, restore the body's degree of peroxidative damage and antioxidant capacity, and inhibit NLRP3 inflammasome and IL-1ß. In vitro, we extracted and identified primary fibroblast-like synoviocytes (FLS) from quail for the first time. Stimulating FLS with uric acid also caused ROS release and NLRP3 inflammasome activation. However, treatment with an XOD inhibitor prevented all these responses in FLS. Conclusion: Our results indicate that the immune response between the uric acid metabolism target XOD and NLRP3 inflammasomes plays a crucial role in developing hyperuricemia to gouty arthritis, and inhibition of both XOD and NLRP3 inflammasomes may be an effective treatment for avoiding the development of asymptomatic hyperuricemia to MSU crystal deposition. Meanwhile, this study also provides an advantageous animal model for pathological mechanisms and research and development drugs for gout.

The Preferential Therapeutic Potential of Chlorella vulgaris against Aflatoxin-Induced Hepatic Injury in Quail.

Aflatoxins (AFs) are the most detrimental mycotoxin, potentially hazardous to animals and humans. AFs in food threaten the health of consumers and cause liver cancer. Therefore, a safe, efficient, and friendly approach is attributed to the control of aflatoxicosis. Therefore, this study aimed to evaluate the impacts of Chlorella vulgaris (CLV) on hepatic aflatoxicosis, aflatoxin residues, and meat quality in quails. Quails were allocated into a control group; the CLV group received CLV (1 g/kg diet); the AF group received an AF-contaminated diet (50 ppb); and the AF+CLV group received both treatments. The results revealed that AF decreased the growth performance and caused a hepatic injury, exhibited as an increase in liver enzymes and disrupted lipid metabolism. In addition, AF induced oxidative stress, exhibited by a dramatic increase in the malondialdehyde (MDA) level and decreases in glutathione (GSH) level, superoxide dismutase (SOD), and glutathione peroxidase (GPx) activities. Significant up-regulation in the inflammatory cytokine (TNF-α, IL-1ß, and IL-6) mRNA expression was also documented. Moreover, aflatoxin residues were detected in the liver and meat with an elevation of fat% alongside a decrease in meat protein%. On the other hand, CLV supplementation ameliorated AF-induced oxidative stress and inflammatory condition in addition to improving the nutritional value of meat and significantly reducing AF residues. CLV mitigated AF-induced hepatic damage, decreased growth performance, and lowered meat quality via its antioxidant and nutritional constituents.

DEHP triggers a damage severity grade increase in the jejunum in quail (Coturnix japonica) by disturbing nuclear xenobiotic receptors and the Nrf2-mediated defense response.

As a plasticizer, di-2-ethylhexyl phthalate (DEHP) has been listed as a potential endocrine disruptor by The World Health Organization. The toxicity of DEHP has been widely studied, but its toxicity on the digestive tract of birds has not been clarified. Female quail were treated by gavage with DEHP (250, 500, 750 mg/kg), with the blank and vehicle control groups reserved. The result showed that DEHP raised the damage severity grade, and decreased the ratio of villus length to crypt depth. The content and activity of cytochrome P450 system (CYP450s) were increased by DEHP. DEHP interfered with the transcription of nuclear xenobiotic receptors (NXRs), CYP isoforms, and the nuclear factor-E2-related factor 2 (Nrf2) signaling pathway. This study revealed DEHP could cause the imbalance in CYP450s mediated by NXRs, and then promote Nrf2 mediated antioxidant defense. This study provided new evidence about the mechanisms of DEHP-induced toxic effects on digestive tract.