Evaluation of black soldier fly larvae oil (Hermatia illucens L.) calcium salt as an alternative fat source for laying quail diets.

Objective: This study aims to determine the effect of adding saponified black soldier fly larvae oil calcium salt (BSFLO-SCa) to quail feed as an alternative source of fat on laying performance, blood lipid profile, egg quality, and gene expression in lipid metabolism. Methods: A total of 120 female Japanese quails (Coturnix japonica) aged 24 weeks were divided into 3 treatments, each with 8 replications, and each replication consisted of 5 quails in a completely randomized design. The applied treatments were the inclusion of basal feed as a control (T0) and basal feed supplemented with 1% BSFLO-SCa (T1) and 2% BSFLO-SCa (T2). Results: The study indicated that the supplementation starting from 1% of BSFLO-SCa significantly decrease (p<0.05) in feed conversion ratio (FCR), blood lipid profile (total cholesterol, LDL-cholesterol). Gene expression on fat synthesis of fatty acid synthase (FAS) and cholesterol synthesis of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR) downregulated (p<0.05). In addition, the other parameters did not affect by supplementation of 1% BSFLO-SCa. The inclusion at 2% of BSFLO-SCa significantly increased (p<0.05) protein content of yolk and albumen, egg weight, egg shape index, and gene expression on fat oxidation of carnitine palmitoyltransferase-1 (CPT-1). Egg yolk cholesterol, egg albumen ash, haugh unit (HU), and gene expression on fat synthesis of acetyl-CoA carboxylase (ACC) were significantly reduced (p<0.05). Conclusion: Addition of 2% BSFLO-SCa in the feed improves performance, egg quality, and reduces cholesterol in the blood and eggs of quail. This improvement is accompanied by a reduction in the expression of key genes involved in lipid metabolism. BSFLO-SCa oil has the potential to be an alternative oil source in quail feed.

Description of the complete rDNA repeat unit structure of Coturnixjaponica Temminck et Schlegel, 1849 (Aves).

Ribosomal RNA (18S, 5.8S, 28S) gene clusters in genomes form regions that consist of multiple tandem repeats. They are located on a single or several pairs of chromosomes and play an important role in the formation of the nucleolus responsible for the assembly of ribosome subunits. The rRNA gene cluster sequences are widely used for taxonomic studies, however at present, complete information on the avian rDNA repeat unit structure including intergenic spacer sequence is available only for the chicken (Gallusgallusdomesticus Linnaeus, 1758). The GC enrichment and high-order repeats peculiarities within the intergenic spacer described for the chicken rDNA cluster may be responsible for these failures. The karyotype of the Japanese quail (Coturnixjaponica Temminck et Schlegel, 1849) deserves close attention because, unlike most birds, it has three pairs of nucleolar organizer bearing chromosomes, two of which are microchromosomes enriched in repeating elements and heterochromatin that carry translocated terminal nucleolar organizers. Here we assembled and annotated the complete Japanese quail ribosomal gene cluster sequence of 21166 base pairs (GenBank under the registration tag BankIt2509210 CoturnixOK523374). This is the second deciphered avian rDNA cluster after the chicken. Despite the revealed high similarity with the chicken corresponding sequence, it has a number of specific features, which include a slightly lower degree of GC content and the presence of bendable elements in the content of both the transcribed spacer I and the non-transcribed intergenic spacer.

Effects of dietary digestible lysine levels in breeding Japanese quails on productive and reproductive performance, egg quality, blood metabolites and immune responses.

BACKGROUND: The vegetable-based diet alone does not provide the lysine (Lys) needed to maximize poultry productive performance. OBJECTIVES: This experiment aimed to evaluate the effects of dietary digestible Lys (dLys) level on productive and reproductive performance, egg quality, blood metabolites and immune responses in breeding Japanese quails (Coturnix japonica). METHODS: The experiment was conducted in a completely randomized design with 6 treatments, 5 replicates and 15 (12 females and 3 meals) 10-week-old breeding Japanese quails each. A basal diet was formulated to meet nutritional requirements of breeding quails except dLys. The basal diet was supplemented with graded (+0.82 g/kg) levels of l-Lys-HCl, corresponding to dietary dLys levels of 0.690%, 0.755%, 0.820%, 0.885%, 0.950% and 1.015%. The experiment lasted for 12 weeks, which was divided into 3-4-week periods. RESULTS: Significant differences were observed for egg production (EP), egg mass (EM) and feed efficiency (FE) in response to increasing dietary dLys concentration with quadratic trends. The highest traits were observed in the birds fed with a diet containing 0.885% dLys. However, feed intake, egg quality, reproductive performance, blood metabolites and immune responses against sheep red blood cell inoculation were not significantly affected by increasing dietary dLys concentrations. The dLys requirements during 11-14, 15-18, 19-22 and 11-22 (overall) weeks of age for optimal EP, EM and FE, based on the quadratic broken-line regression analysis, were estimated 272, 265, 250 and 266; 293, 285, 264 and 279; and 303, 294, 281 and 293 mg/bird/day, respectively. CONCLUSIONS: The dLys requirements vary depending on the EP phase and the trait being optimized. The estimated dLys requirement for FE was higher than those for EP and EM. During the peak stage of the first laying cycle, the dietary dLys level of 0.932% and a daily intake of 303 mg dLys/bird are sufficient for optimal performance.

Heart-specific expression of the green fluorescent protein gene in avian embryos by administration of recombinant adenovirus type-5 vector into the embryonic blood vessel.

Genetic modification in vivo could provide direct functions of genes that could potentially contribute to diverse areas of research including genetics, developmental biology, and physiology. It has been reported that genes of interest could be introduced via recombinant adenovirus type 5 (Ad5) in poultry. Successful gene delivery to mammal fetuses in utero promises substantial progress in clinical and developmental biology, but it is limited because of difficulties in injecting specific sites and invasiveness. On the other hand, developing avian embryos are easily accessible by making a window on the eggshell. Therefore, the objective of this study is to determine permissive embryonic stages for gene transfer into specific avian tissue/organs by injection of Ad5 containing the green fluorescent protein (GFP) gene into blood vessels. At 2 d of post-injection, a strong GFP signal was predominantly identified in the heart of chicken embryos injected at Hamilton-Hamburger (HH) 14, 15, 16 and17 stages with the percentages (44%, 53%, 25%, and 14%, respectively) of GFP positive embryos. In quail embryos, the injection at the HH 15 resulted in heart-specific expression of GFP. Western blot analysis revealed that GFP was exclusively expressed in the avian hearts. These results suggest that the GFP gene is specifically delivered to the avian embryonic hearts when Ad5 is injected through the blood vessel at HH 14-17. This adenoviral transduction of genes of interest in avian embryonic hearts can provide new models for understanding functions of genetic factors on embryonic heart development and unravel genetic etiology of congenital heart diseases.

Exploring neuronal markers and early social environment influence in divergent quail lines selected for social motivation.

Many species, including humans exhibit a wide range of social behaviors that are crucial for the adaptation and survival of most species. Brain organization and function are shaped by genetic and environmental factors, although their precise contributions have been relatively understudied in the context of artificial selection. We used divergent lines of quail selected on their high versus low level of motivation to approach a group of conspecifics (S + and S-, respectively) to investigate the influence of genetic selection and early social environment on sociability. We observed distinct sex- and brain-region-specific expression patterns of three neuronal markers: mesotocin, and vasotocin, the avian homologues of mammalian oxytocin and vasopressin, as well as aromatase, the enzyme that converts androgens into estrogens. These markers displayed pronounced and neuroanatomically specific differences between S + and S- quail. Additionally, in a second experiment, we assessed the influence of early social environment on social skills in juvenile birds. Mixing S + and S- resulted in more S- males approaching the group without affecting the sociability of S + or other behaviors, suggesting that the early social environment may influence the results of genetic selection. In conclusion, the divergent quail lines offer a valuable model for unraveling the neuronal and behavioral mechanisms underlying social behaviors.

Use of corn germ meal and bile acids in laying quail diets: effect on production, reproduction, health and economics.

In the present study, the effects of corn germ meal (CGM) and bile acids (BA) inclusion in Japanese quail diet on the productive and reproductive performance, egg quality, and serum biochemical parameters were evaluated. Six wk old, 480 Japanese quail birds were randomly divided into 6 groups (60 hens and 20 males / group) with 4 replicates / group. CGM was incorporated at 0, 10 and 20 % of diet for groups (G1, G2, and G3), while G4, G5 and G6 had the same levels of CGM with BA addition (500 g/ton feed). The egg production (EP), egg mass (EM) and feed intake (FI) were significantly reduced (P < 0.05) in response to CGM feeding which was clear with the 20 %. CGM at 10% inclusion enhanced the feed conversion ratio (FCR), while incorporation at 20% deteriorated (P < 0.05) it compared to the control group. Addition of BA to the CGM-containing diets reduced the FI, improved FCR, and ameliorated the negative effects on EP, EM and FCR in the CGM fed birds. Feeding on 10% CGM single or combined with BA increased fertility %, chick's weight after hatching and reduced embryonic death. Serum concentrations of triglyceride and low-density lipoprotein (LDL) were significantly increased (P < 0.05) with CGM inclusion. Dietary CGM inclusion without or with BA was associated with higher levels of serum total cholesterol and low-density lipoprotein when compared to their control groups. BA addition to the CGM containing diets significantly reduced the alanine transaminase (ALT) activity (P ˂ 0.05) compared to their corresponding groups fed BA free diets especially those received the 10% CGM. Birds fed on 10% CGM supplemented with BA showed the highest economic efficiency values. In conclusion, CGM inclusion at 10% with BA supplementation could be used as alternative ingredient in the Japanese quail layer diet without compromising their productive performance.

Genetic features of avian influenza (A/H5N8) clade 2.3.4.4b isolated from quail in Egypt.

Several genotypes of the highly pathogenic avian influenza (HPAI) virus H5N8 subtype within clade 2.3.4.4b continue to circulate in different species of domestic birds across Egypt. It is believed that quail contribute to virus replication and adaptation to other gallinaceous poultry species and humans. This study provides genetic characterization of the full genome of HPAI H5N8 isolated from quail in Egypt. The virus was isolated from a commercial quail farm associated with respiratory signs. To characterize the genetic features of the detected virus, gene sequencing via Sanger technology and phylogenetic analysis were performed. The results revealed high nucleotide identity with the HPAI H5N8 virus from Egypt, which has multiple basic amino acid motifs PLREKRRKR/GLF at the hemagglutinin (HA) cleavage site. Phylogenetic analysis of the eight gene segments revealed that the quail isolate is grouped with HPAI H5N8 viruses of clade 2.3.4.4b and closely related to the most recent circulating H5N8 viruses in Egypt. Whole-genome characterization revealed amino acid preferences for avian receptors with few mutations, indicating their affinity for human-like receptors and increased virulence in mammals, such as S123P, S133A, T156A and A263T in the HA gene. In addition, the sequencing results revealed a lack of markers associated with influenza antiviral resistance in the neuraminidase and matrix-2 coding proteins. The results of the present study support the spread of HPAIV H5N8 to species other than chickens in Egypt. Therefore, continuous surveillance of AIV in different bird species in Egypt followed by full genomic characterization is needed for better virus control and prevention.

Exploration of Some Nutrient Absorption-Related Genes and Intestinal Histology in Japanese Quails (Coturnix japonica) Throughout Their Productive Lifespan.

BACKGROUND: Quail is an efficient poultry species known for many years, and its productivity is highly affected by gastrointestinal function, health, digestion and commensal bacteria. Specific histological parameters and nutrient absorption-related genes could be used to study intestinal functionality and efficiency. OBJECTIVES: This study aimed to evaluate the mRNA abundance of nutrient absorption-related genes and intestinal histology changes in laying Japanese quail during productive lifespan. METHODS: A total of 135 quails from a commercial flock at different egg production periods (early production [EP, 6 weeks of age], pick production [PP, 21 weeks of age] and post pick production [PPP, 40 weeks of age]) were randomly selected (n = 45/group) and kept for 6 weeks. Production performance was evaluated during last 2 weeks of the experimental period, and tissue samples were taken from the duodenum, jejunum and ileum for histological analysis and mRNA abundance purposes at the end of the experiment. The mRNA abundance of the CALB1, SGLT1, SGLT5, EAAT3 and NaPi-IIb genes were compared among groups. RESULTS: Production period did not affect the eggshell thickness, goblet cell number and mRNA abundance of CALB1, EAAT3 and NaPi-IIb (p > 0.05). The PPP quails had the highest egg weight and FCR compared to EP and PP quails (p < 0.001). Egg production and egg mass of the EP and PP quails were higher than those of PPP quails (p < 0.001). Moreover, EP quails had the highest villus height (VH)/crypt depth (CD) ratio in the duodenum and jejunum and the lowest VH:CD in the ileum compared with the PPP quails (p < 0.01). The lowest SGLT1 mRNA abundance was noted in the PP quails, whereas EP quails had the highest SGLT5 mRNA abundance (p < 0.05). CONCLUSIONS: In conclusion, although histology parameter changes were in-line with the lowest performance observed in the PPP quails, the current results failed to show a relationship between mRNA abundance changes and production performance attributes at different productive lifespans.

Responses of Jumbo Quail to a Diet Containing Corticated Marama Bean (Tylosema esculentum) Meal Pre-Treated with Fibrolytic Multi-Enzymes.

The nutritional utility of leguminous products such as corticated marama bean (Tylosema esculentum) meal (CMBM) in quail diets is limited by high fibre levels. This study evaluated the impact of dietary CMBM pre-treated with fibrolytic multi-enzyme (FMENZ) on growth performance, and physiological and meat quality responses in Jumbo Coturnix quail. Two hundred and forty 7-day-old Jumbo quail (29.4 ± 2.72 g initial live weight) were randomly distributed to five experimental diets, with six replicate cages each (eight birds/cage). The diets were a grower diet without CMBM, and the same grower diet plus 100 g/kg CMBM pre-treated with 0, 1, 1.5, and 2% (v/w) FMENZ. Positive quadratic responses (p < 0.05) were recorded for overall feed intake and body weight gain in weeks 2 and 3. The control diet promoted the highest (p < 0.05) gain-to-feed ratio in weeks 2 and 3, and the best weight gains and glucose levels, but reduced lipase levels. Final body weights declined linearly [p = 0.037] with FMENZ levels. Breast pH increased linearly, while haemoglobin and 1 h post-mortem chroma showed positive quadratic effects (p < 0.05) with FMENZ levels. The use of the enzymes did not improve the feed value of CMBM in Jumbo quail diets.

Inbreeding accelerates reproductive senescence, but not survival senescence, in a precocial bird.

Inbreeding depression is predicted to increase with age, because natural selection is less efficient at purging deleterious alleles that are only expressed later in life. However, empirical results are scarce, and equivocal between studies. Here we performed controlled matings between related and unrelated individuals of domesticated Japanese quail (Coturnix japonica), and monitored the performance of their offspring for all fitness components over their complete life course. We found rapid senescence in adult survival and egg laying performance, and inbreeding depression at all life stages (reduced embryo viability, increased age at maturity, as well as reduced adult survival and reproduction). Inbreeding depression did not increase at later ages for survival, but did so for egg laying, thereby accelerating reproductive senescence. Moreover, the effect of inbreeding on egg laying persisted after correcting for lifespan, indicating that both survival and reproduction were independently affected by inbreeding. We suggest that in heterogeneous populations intra-generational purging may at earlier ages already select out the individuals that are homozygous for the specific alleles responsible for depressed survival, preventing the appearance of increased inbreeding depression in survival with age. Given that inbreeding affects reproduction independent of survival this should not apply to reproductive senescence or homogeneous populations, which may explain equivocal results between traits and studies.

Deciphering avian hematopoietic stem cells by surface marker screening and gene expression profiling.

BACKGROUND: Avian species have played a pivotal role in developmental hematopoiesis research, leading to numerous critical discoveries. Avian influenza, particularly the H5N1 strain, poses a significant threat to poultry and has zoonotic potential for humans. Infections often result in abnormal hematologic profiles, highlighting the complex interplay between avian diseases and hematopoiesis. Many avian diseases can suppress immune cells in the bone marrow (BM), impacting immune responses. Studying hematopoietic stem cells (HSCs) in avian BM is crucial for understanding these processes and developing effective vaccines and protection strategies for both avian and human health. METHODS: This study adapted methods from mouse studies to isolate avian HSCs as Lineage-negative (Lin-) cells. These isolated cells were further identified as Lin-Sca1+c-Kit+ (LSK) and were found to be more prevalent than in control groups. RT-PCR analyses were conducted, showing that genes like MEIS1 and TSC1 were upregulated, while SIRT1, FOXO1, and AHR were downregulated in these stem cells. Screening for LSK markers revealed ten unique surface antigens in the Sca1+c-Kit+ cell populations, including highly enriched antigens such as CD178, CD227, and CD184. Additionally, studies on quail HSCs demonstrated that similar labeling techniques were effective in quail BM. RESULTS: The research demonstrated that the identification of avian HSC-specific surface antigens provides valuable insights into the pathogenesis of avian influenza and other diseases, enhancing our understanding of how these diseases suppress HSC function. Notably, the upregulation of MEIS1 and TSC1 genes in LSK cells underscores their critical roles in regulating hematopoietic processes. Conversely, the downregulation of SIRT1, FOXO1, and AHR genes provides important clues about their roles in differentiation and immune response mechanisms. DISCUSSION: The findings of this study deepen our understanding of the effects of avian diseases on the immune system by identifying surface markers specific to avian HSCs. The suppression of HSC function by pathogens such as influenza highlights the importance of understanding these cells in developing targeted vaccines. These results represent a significant step towards improving global health security by mitigating risks associated with avian pathogens.

Early-life group size influences response inhibition, but not the learning of it, in Japanese quails.

In complex social environments, animals benefit from suppressing inappropriate responses (known as Response Inhibition) to avoid conflicts and maintain group cohesion. Recent research suggests that an individual's early-life social environment can shape their response inhibition. However, these findings have mostly been correlational, and results vary across species. Furthermore, the role of learning is often overlooked when measuring response inhibition, despite its potential importance to understanding group differences. We investigated the effect of early-life group size, a key determinant of social complexity, on response inhibition in Japanese quails (Coturnix japonica), whilst taking the role of learning into account. Quails (n = 120) were raised in either small groups of five or large groups of 15 individuals. Response inhibition was assessed using the cylinder task. Up to ten trials were administered to assess whether the birds' responses changed with increasing experience of the task. Among the quails that completed ten trials, we found that those raised in large groups consistently spent less time pecking the cylinder than those raised in small groups. The quails' responses were also influenced by their body condition, food motivation and sex. Importantly, the quails learned to inhibit their responses - successful trials increased, and time spent pecking the cylinder decreased, across ten trials. However, learning rates did not differ between the treatment groups. These findings suggest that early-life social group size promotes the development of response inhibition in quails, but not their learning of it, during the cylinder task.

Antibacterial effect of ethanolic Gnetum gnemon L. leaf extract on food-borne pathogens and its application as a natural preservative on raw quail eggs.

Gnetum gnemon L. is an evergreen tree that belongs to the Gnetaceae family and is commonly used as a vegetable and medicinal plant among indigenous people. The key goal of this study was to assess the antibacterial efficacy of ethanolic G. gnemon leaf extract (EGLE) against six food-borne pathogens. The antimicrobial activity of EGLE was evaluated using multiple methods, including the well diffusion assay (WDA), minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and time-kill assay. Gas Chromatography-Mass Spectrometry (GC-MS) analysis was used to identify active volatile compounds responsible for EGLE's antibacterial activities. Total plate count (TPC) was conducted to measure microbial populations and evaluate the efficacy of EGLE as a natural preservative in raw quail eggs. 100 g of dried and powdered sample yielded an average of 11.58 ± 0.38 % post-extraction. The inhibition zone in WDA ranged from 11.00 ± 0.57-13.50 ± 0.58 mm, MIC ranged from 6.25 to 50.00 mg/mL, and MBC values were between 12.5 and >50 mg/mL. Results from the time-kill study showed that at 4 × MIC Bacillus pumilus and B. megaterium were completely killed in 1 h incubation time and other bacteria were killed within 2-4 h. Findings from TPC demonstrated that at the highest tested concentration of EGLE, there was no significant bacterial growth for a 30-day observation period. Thereby, suggesting that it had the potential to function as a natural preservative for raw quail eggs. EGLE may be a viable alternative to synthetic preservatives in combating food-borne pathogens.

Changes in performance, cecal microflora counts and intestinal histology of Japanese quails fed diets containing different fibre sources.

The purpose of this experiment was to investigate how various fiber sources impact the performance, microbial population, and intestinal histology of Japanese quail that was performed in a completely randomized design for 42 days. The dietary treatments involved a fiber-free corn-soybean meal-based diet (control, CTL), and CTL with added levels of sunflower hulls (SFH) and sugar beet pulp (SBP) (20 and 40 g kg-1). Body weight gain (BWG) and feed intake (FI) were recorded weekly. Carcass characteristics, cecal microbial population, blood variables and intestinal histology were measured on the 42 day of age. Adding 40 g kg-1 of SBP led to a significant decrease in body weight gain and an increase in the feed conversion ratio of birds from 1 to 21 days (P < 0.05). The relative weight of the gastrointestinal tract and gizzard increased significantly in birds that consumed SFH. Blood triglyceride concentration decreased with the inclusion of fiber in the diet. However, there was a notable increase in blood cholesterol concentration in the birds that were fed SBP (20 and 40 g kg-1) in comparison to those fed SFH (P < 0.05). The population of E. Coli in the cecum increased significantly in the birds that were fed 4 g kg-1 of SBP as opposed to those fed 20 and 40 g kg-1 of SFH (P < 0.05). The villus height of the jejunum in birds that were fed 20 g kg-1 and 40 g kg-1 of SFH demonstrated a significant increase in comparison to the other treatments (P < 0.05). In general, the findings of this research indicated that the inclusion of 40 g kg-1 of SBP in the diet had a negative impact on performance and other physiological parameters. However, the use of SFH and 20 g kg-1 of SBP yielded similar results to birds in the CTL, and in some cases, even better outcomes.

Plasma activated water effects on behavior, performance, carcass quality, biochemical changes, and histopathological alterations in quail.

BACKGROUND: Plasma-activated water (PAW) is an innovative promising technology which could be applied to improve poultry health. The current study investigated the effects of drinking water supply with PAW on quail behaviour, performance, biochemical parameters, carcass quality, intestinal microbial populations, and internal organs histopathology. A total of 54 twenty-one-day-old Japanese quail chicks were randomly allotted to three treatments provided with PAW at doses 0, 1 ml (PAW-1), and 2 ml (PAW-2) per one litter drinking water. Each treatment contained 6 replicates (3 birds/ cage; one male and two females). RESULTS: The results clarified that there were no significant (P > 0.05) changes in behaviour, and performance. For the biochemical indicators, the PAW-1 group showed significantly higher serum H2O2, total protein and globulin levels compared with the other groups (P = 0.015, < 0.001, and 0.019; respectively). PAW groups had significantly lower serum creatinine and urea levels than the control (P = 0.003). For the carcass quality, the internal organs relative weight between different treatments was not changed. In contrast, there was a significant increase in the meat colour, taste, and overall acceptance scores in PAW groups compared with the control one (P = 0.013, 0.001, and < 0.001; respectively). For the intestinal microbial population, lactobacilli count was significantly higher in PAW-2 compared with the control group (P = 0.014), while there were no changes in the total bacterial count between different treatment groups. Moreover, mild histological changes were recorded in the intestine, liver, and spleen of PAW groups especially PAW-2 compared with the control one. CONCLUSIONS: PAW offered benefits, such as reducing creatine and urea levels, improving meat characteristics, and increasing lactobacilli count, all of which are crucial for sustainable quail farming. Therefore, further research is needed.

Evaluation of dietary supplementation of garlic powder (Allium sativum) on the growth performance, carcass traits and meat quality of Japanese quails (Coturnix coturnix japonica).

Dietary supplementation with plant-based products may arise as part of an alternative strategy to using antibiotics as growth promoters in the poultry industry. Garlic powder (GP) possesses antimicrobial and antioxidant properties. The aim was to investigate the effect of dietary supplementation of GP on growth performance, carcass traits and meat quality of the Japanese quail. A total of 240, day-old mixed gender Japanese quail were assigned to 4 treatment groups, each group being replicated 4 times and containing 15 birds in each replication. Birds were provided with either a basal diet (control) or basal diet supplemented with 0.5%, 1% and 2% GP for 5 wk. At slaughter age, birds fed 1% GP had higher (P < 0.05) live weight and body weight gain when compared to the control. Supplementation with different levels of GP had no influence (P > 0.05) on feed intake, feed conversion ratio except 3rd wk, carcass traits and abdominal fat. Thiobarbituric acid, peroxide and pH values in breast meat of birds receiving GP (1% or 2%) after storage (0, 1, 3, 5, and 7 d) were lower (P < 0.05) than the birds in control. Furthermore, total psychrophilic bacteria count was lower in breast meat of birds supplemented with GP at any dose compared to the birds of control. Sensory characteristics such as color, aroma, juiciness and tenderness were observed significantly better (P < 0.05) in GP supplemented groups especially when fed 1% GP. In conclusion, supplementing the diet with 1% to 2% GP demonstrated growth-promoting effects and positively impacted meat quality, including sensory characteristics.

Development and Characterization of Primary Brain Cultures from Japanese Quail Embryos.

Cell cultures play a crucial role in neuroscience research, facilitating the elucidation of the complexities of cellular physiology and pathology. The relative simplicity in producing cultures and the accessibility to cells that the cultures provide, in contrast to in vivo settings, allow users to manipulate and monitor cells more easily at higher throughputs and lower costs. These are ideal for screening purposes and electrophysiological characterizations. Despite the prevalence of methodologies for producing brain cultures from various animal models, rodents in particular, approaches for culturing neurons (and glia) from birds are less established or completely absent as in the case of the Japanese quail model. Here, we present a unique culturing protocol for brain cells (e.g., neurons at different maturation levels, such as progenitor cells, excitatory and inhibitory neurons, microglia, and endothelial cells) from entire forebrains of Japanese quail embryos for high-throughput screening of viral vectors in vitro and other various purposes. Following dissection and digestion methods uniquely suited for avian brains, we tailored the growth media and culturing surface to allow the survival of quail brain cultures for more than three weeks in vitro. Key features • We introduce a detailed protocol for producing primary brain cultures from quail embryos' forebrains for up to 30 days. • We show that the cultures support in vitro viral transfections effectively. • We demonstrate the use of the cultures for rapid (days) screening for suitable viruses for quail brain cells, electrophysiological characterizations, and single mRNA sequencing.

Retinoic acid, an essential component of the roof plate organizer, promotes the spatiotemporal segregation of dorsal neural fates.

Dorsal neural tube-derived retinoic acid promotes the end of neural crest production and transition into a definitive roof plate. Here, we analyze how this impacts the segregation of central and peripheral lineages, a process essential for tissue patterning and function. Localized in ovo inhibition in quail embryos of retinoic acid activity followed by single-cell transcriptomics unraveled a comprehensive list of differentially expressed genes relevant to these processes. Importantly, progenitors co-expressed neural crest, roof plate and dI1 interneuron markers, indicating a failure in proper lineage segregation. Furthermore, separation between roof plate and dI1 interneurons is mediated by Notch activity downstream of retinoic acid, highlighting their crucial role in establishing the roof plate-dI1 boundary. Within the peripheral branch, where absence of retinoic acid resulted in neural crest production and emigration extending into the roof plate stage, sensory progenitors failed to separate from melanocytes, leading to formation of a common glia-melanocyte cell with aberrant migratory patterns. In summary, the implementation of single-cell RNA sequencing facilitated the discovery and characterization of a molecular mechanism responsible for the segregation of dorsal neural fates during development.

Transparent mechanism of salted egg (white) hierarchically and synergistically driven by NaCl, NaOH and thermal treatment: Based on empirical data and molecular simulation.

Currently, it is a challenge that the yolk in salted preserved egg tends to preserved egg yolk due to extreme NaOH treatment. Therefore, NaCl, NaOH and thermal were successfully used to prepare a new translucent salted quail egg (T-SQE), which combined advantages of preserved egg white with transparent appearance and salted egg yolk with unique texture and odour. Moreover, transparency of opaque gel (Transmittance: 0.09 %) subjected to NaCl and thermal was demonstrated to be improved under the synergistic effect of NaOH (8.55 %) via empirical data and molecular simulation. The disordered and dense network in opaque T-SQE induced by NaCl and thermal tended to form an ordered, porous and transparent structure in presence of NaOH, with more immobilized water that was poorly bonded to protein, larger radius of gyration and lower hydrophobic interaction. This research provides new insight into understanding the influence of hierarchy and synergism on transparency of egg products.

Elevated temperature affects the expression of signaling molecules in quail testes meiosis I prophase, but spermatogenesis remains normal.

Spermatogenesis in eukaryotes is a process that occurs within a very narrow temperature threshold, typically not exceeding 36 °C. SPO11 was isolated from the temperature-sensitive mutant receptor of Saccharomyces cerevisiae and is thought to be the only protein that functions during meiosis. This suggested that SPO11 may be the key protein that influenced the temperature of spermatogenesis not exceeding 36 °C. Elevated temperatures typically damage the spermatogenic cells. Birds have a core body temperature of 41-42 °C, and their testis are located inside their bodies, providing an alternative perspective to investigate the potential impact of temperature threshold on spermatogenesis. The objective of this study was to ascertain whether elevated ambient temperatures affect spermatogenesis in birds and whether SPO11 is the key gene affecting the temperature threshold for spermatogenesis. STRA8, SCP3, SPO11, γ-H2AX, and RAD51 were all crucial components in the process of meiotic initiation, synapsis, DNA double-strand break (DSB) induction, homologous chromosome crossover recombination, and repair of DSB. In this study, 39-day-old Japanese quail were subjected to heat stress (HS) at 38 °C for 8 h per day for 3 (3d HS) and 13 (13d HS) consecutive days and analyzed the expression of meiotic signaling molecules (STRA8, SCP3, SPO11, γ-H2AX, and RAD51) using molecular biology techniques, including Immunohistochemistry (IHC), Western Blot (WB), and Real-time Quantitative Polymerase Chain Reaction (qRT-PCR). We found that spermatogenesis was normal in both groups exposed to HS. Meiotic signaling molecules were expressed normally in the 3d HS group. All detected signaling molecules were normally expressed in the 13d HS group, except for SPO11, which showed a significant increase in expression, indicating that SPO11 was temperature-sensitive. We examined the localized expression of each meiotic signaling molecule in quail testis, explored the temperature sensitivity of SPO11, and determined that quail testis can undergo normal spermatogenesis at ambient temperatures exceeding 36 °C. This study concluded that SPO11 is not the key protein influencing spermatogenesis in birds. These findings enhance our understanding of avian spermatogenesis.