Structural gonadal lesions observed in Japanese quail (Coturnix coturnix japonica) following exposure during puberty to the neonicotinoid pesticide, imidacloprid.

Exposure to the neonicotinoid insecticide, imidacloprid (IMI), causes reproductive toxicity in mammals and reptiles. However, reports on the effects of IMI on the gonads in birds are grossly lacking. Therefore, this study investigated the effects of pubertal exposure to IMI on the histology, ultrastructure, as well as the cytoskeletal proteins, desmin, smooth muscle actin and vimentin, of the gonads of Japanese quail (Coturnix coturnix japonica). Quails were randomly divided into four groups at 5 weeks of age. The control group was given only distilled water, whereas, the other three experimental groups, IMI was administered by oral gavage at 1.55, 3.1, and 6.2 mg/kg, twice per week for 4 weeks. Exposure to IMI doses of 3.1 and 6.2 mg/kg caused dose-dependent histopathological changes in the ovary and testis. In the ovary, accumulation of lymphocytes, degenerative changes, and necrosis with granulocyte infiltrations were observed, while in the testis, distorted seminiferous tubules, germ cell sloughing, vacuolisations, apoptotic bodies, autophagosomes, and mitochondrial damage were detected. These changes were accompanied by a decreased number of primary follicles (P ≤ 0.05) in the ovary and a decrease (P ≤ 0.05) in the epithelial height, luminal, and tubular diameters of seminiferous tubules at the two higher dosages. In addition, IMI had a negative effect on the immunostaining intensity of desmin, smooth muscle actin, and vimentin in the ovarian and testicular tissue. In conclusion, exposure to IMI during puberty can lead to a range of histopathological alterations in the gonads of Japanese quails, which may ultimately result in infertility.

Mitogenomic Insights into the Evolution, Divergence Time, and Ancestral Ranges of Coturnix Quails.

The Old-World quails, Coturnix coturnix (common quail) and Coturnix japonica (Japanese quail), are morphologically similar yet occupy distinct geographic ranges. This study aimed to elucidate their evolutionary trajectory and ancestral distribution patterns through a thorough analysis of their mitochondrial genomes. Mitogenomic analysis revealed high structural conservation, identical translational mechanisms, and similar evolutionary pressures in both species. Selection analysis revealed significant evidence of positive selection across the Coturnix lineage for the nad4 gene tree owing to environmental changes and acclimatization requirements during its evolutionary history. Divergence time estimations imply that diversification among Coturnix species occurred in the mid-Miocene (13.89 Ma), and their current distributions were primarily shaped by dispersal rather than global vicariance events. Phylogenetic analysis indicates a close relationship between C. coturnix and C. japonica, with divergence estimated at 2.25 Ma during the Pleistocene epoch. Ancestral range reconstructions indicate that the ancestors of the Coturnix clade were distributed over the Oriental region. C. coturnix subsequently dispersed to Eurasia and Africa, and C. japonica to eastern Asia. We hypothesize that the current geographic distributions of C. coturnix and C. japonica result from their unique dispersal strategies, developed to evade interspecific territoriality and influenced by the Tibetan Plateau's geographic constraints. This study advances our understanding of the biogeographic and evolutionary processes leading to the diversification of C. coturnix and C. japonica, laying important groundwork for further research on this genus.

Sex-specific effects of dietary restriction on physiological variables in Japanese quails.

Nutritional limitation is a common phenomenon in nature that leads to trade-offs among processes competing for limited resources. These trade-offs are mediated by changes in physiological traits such as growth factors and circulating lipids. However, studies addressing the sex-specific effect of nutritional deficiency on these physiological variables are limited in birds. We used dietary restriction to mimic the depletion of resources to various degrees and investigated sex-specific effects on circulating levels of insulin-like growth factor 1 (IGF-1) and triglycerides in Japanese quails (Coturnix japonica) subjected to ad libitum, 20%, 30% or 40% restriction of their daily requirement, for 2 weeks. We also explored the association of both physiological variables with body mass and egg production. While dietary restriction showed no effects on circulating IGF-1, this hormone exhibited a marked sexual difference, with females having 64.7% higher IGF-1 levels than males. Dietary restriction significantly reduced plasma triglyceride levels in both sexes. Females showed more than six-fold higher triglyceride levels than males. Triglyceride levels were positively associated with body mass in females while showed not association in males. Overall, our findings revealed sex-specific expression of physiological variables under dietary restriction conditions, which coincide with body size.

Genetic parameters for cloacal gland, sexual maturity, reproductive organs weight, and body weight in meat-type quail.

Selection to increase body weight in poultry can hamper reproduction traits and compromise production efficiency. Thus, attention to reproduction traits is essential to improving the sustainability of breeding programs. Data from a domestic quail breeding program for meat production were used to estimate genetic parameters. We analyzed five traits: 4-week body weight, age at sexual maturity for males and females, cloacal gland area, female, and male reproductive organs weights. A multi-trait mixed model analysis with fixed effects of generation/hatch was performed, assuming environmental covariance equals zero for sex-limited traits. Heritability estimates range from low to moderate for male sexual maturity and cloacal gland area, and high for other traits. Intersexual genetic correlation for age at sexual maturity is positive, which can lead to correlated responses in the other sex. Reproductive organs weights are genetically correlated with body weight, but not significantly between sexes and nor with sexual maturity. Genetic correlations for the cloacal gland area were positive with body weight and negative with age at sexual maturity of males and females, demonstrating a potential use of this trait for selection with favorable outcomes in reproduction. The use of the cloacal gland area can be used in the same way as the scrotal circumference in mammals, improving female reproduction traits by selecting a trait recorded in males.

Effects of Se-enriched yeast on the amelioration of atrazine-induced meat quality degradation.

Atrazine (ATR) is herbicide that causes serious harm to the environment and threatens human food safety. Se-enriched yeast is the best organic selenium source for protecting cells from damage caused by poisonous substances. To explore mechanism of ATR on meat quality degradation and potential protective effects of Se-enriched yeast on ATR-induced muscle injury, quails were treated with ATR and/or Se-enriched yeast for 28 days. The results found ATR disrupted muscle fiber structure and decreased pH, tenderness, water-holding capacity, essential amino acid content and polyunsaturated fatty acid content. ATR aggravated oxidative stress and inflammation by inhibiting Nrf2 pathway and activating NF-κB pathway, ultimately causing apoptosis. However, Se-enriched yeast alleviated ATR-induced alterations in muscle chemical and physical properties by inhibiting oxidative stress and inflammation. Taken together, these results revealed that ATR exposure caused meat quality degradation and Se-enriched yeast had the potential to counteract ATR-induced myotoxicity by inhibiting oxidative stress and inflammation.

Dietary restriction and life-history trade-offs: insights into mTOR pathway regulation and reproductive investment in Japanese quail.

Resources are needed for growth, reproduction and survival, and organisms must trade off limited resources among competing processes. Nutritional availability in organisms is sensed and monitored by nutrient-sensing pathways that can trigger physiological changes or alter gene expression. Previous studies have proposed that one such signalling pathway, the mechanistic target of rapamycin (mTOR), underpins a form of adaptive plasticity when individuals encounter constraints in their energy budget. Despite the fundamental importance of this process in evolutionary biology, how nutritional limitation is regulated through the expression of genes governing this pathway and its consequential effects on fitness remain understudied, particularly in birds. We used dietary restriction to simulate resource depletion and examined its effects on body mass, reproduction and gene expression in Japanese quails (Coturnix japonica). Quails were subjected to feeding at 20%, 30% and 40% restriction levels or ad libitum for 2 weeks. All restricted groups exhibited reduced body mass, whereas reductions in the number and mass of eggs were observed only under more severe restrictions. Additionally, dietary restriction led to decreased expression of mTOR and insulin-like growth factor 1 (IGF1), whereas the ribosomal protein S6 kinase 1 (RPS6K1) and autophagy-related genes (ATG9A and ATG5) were upregulated. The pattern in which mTOR responded to restriction was similar to that for body mass. Regardless of the treatment, proportionally higher reproductive investment was associated with individual variation in mTOR expression. These findings reveal the connection between dietary intake and the expression of mTOR and related genes in this pathway.

Age-related changes in testicular histological structure, testosterone level, libido and semen traits in male Coturnix quail.

To investigate the effect of age in male quail on testicular weight and histology, sexual libido and semen characteristics, a study was performed on 100 quails at 10, 16, 22, 28 and 34 weeks of age. The body and testicular weights were significantly (p < .05) higher at 16 and 22 than at 28 weeks of age. The circumference and diameter of the seminiferous tubules were significantly (p < .05) higher at 28 and 34 than at 10 and 16 weeks of age. Histological evaluation of testicular slices revealed advanced and effective seminiferous tubes as early as 10 weeks, while spermatogenic activity peaked at 16 weeks of age. The highest semen volume, sperm motility and sperm concentration were observed at weeks of age and then decreased gradually with age. At the same time, the testosterone level and libido were significantly (p < .05) higher at 22 than at 10 weeks of age. Furthermore, the age was positive (p < .05), correlated to seminiferous tubule circumference and diameter, and negative (p < .05), correlated to sperm concentration. In conclusion, the age of quail markedly affected the testicular histological structure, libido, testosterone level and semen characteristics.

Dissociating Mechanisms That Underlie Seasonal and Developmental Programs for the Neuroendocrine Control of Physiology in Birds.

Long-term programmed rheostatic changes in physiology are essential for animal fitness. Hypothalamic nuclei and the pituitary gland govern key developmental and seasonal transitions in reproduction. The aim of this study was to identify the molecular substrates that are common and unique to developmental and seasonal timing. Adult and juvenile quail were collected from reproductively mature and immature states, and key molecular targets were examined in the mediobasal hypothalamus (MBH) and pituitary gland. qRT-PCR assays established deiodinase type 2 (DIO2) and type 3 (DIO3) expression in adults changed with photoperiod manipulations. However, DIO2 and DIO3 remain constitutively expressed in juveniles. Pituitary gland transcriptome analyses established that 340 transcripts were differentially expressed across seasonal photoperiod programs and 1,189 transcripts displayed age-dependent variation in expression. Prolactin (PRL) and follicle-stimulating hormone subunit beta (FSHß) are molecular markers of seasonal programs and are significantly upregulated in long photoperiod conditions. Growth hormone expression was significantly upregulated in juvenile quail, regardless of photoperiodic condition. These findings indicate that a level of cell autonomy in the pituitary gland governs seasonal and developmental programs in physiology. Overall, this paper yields novel insights into the molecular mechanisms that govern developmental programs and adult brain plasticity.

The dynamic landscape of chromatin accessibility and active regulatory elements in the mediobasal hypothalamus influences the seasonal activation of the reproductive axis in the male quail under long light exposure.

BACKGROUND: In cold and temperate zones, seasonal reproduction plays a crucial role in the survival and reproductive success of species. The photoperiod influences reproductive processes in seasonal breeders through the hypothalamic-pituitary-gonadal (HPG) axis, in which the mediobasal hypothalamus (MBH) serves as the central region responsible for transmitting light information to the endocrine system. However, the cis-regulatory elements and the transcriptional activation mechanisms related to seasonal activation of the reproductive axis in MBH remain largely unclear. In this study, an artificial photoperiod program was used to induce the HPG axis activation in male quails, and we compared changes in chromatin accessibility changes during the seasonal activation of the HPG axis. RESULTS: Alterations in chromatin accessibility occurred in the mediobasal hypothalamus (MBH) and stabilized at LD7 during the activation of the HPG axis. Most open chromatin regions (OCRs) are enriched mainly in introns and distal intergenic regions. The differentially accessible regions (DARs) showed enrichment of binding motifs of the RFX, NKX, and MEF family of transcription factors that gained-loss accessibility under long-day conditions, while the binding motifs of the nuclear receptor (NR) superfamily and BZIP family gained-open accessibility. Retinoic acid signaling and GTPase-mediated signal transduction are involved in adaptation to long days and maintenance of the HPG axis activation. According to our footprint analysis, three clock-output genes (TEF, DBP, and HLF) and the THRA were the first responders to long days in LD3. THRB, NR3C2, AR, and NR3C1 are the key players associated with the initiation and maintenance of the activation of the HPG axis, which appeared at LD7 and tended to be stable under long-day conditions. By integrating chromatin and the transcriptome, three genes (DIO2, SLC16A2, and PDE6H) involved in thyroid hormone signaling showed differential chromatin accessibility and expression levels during the seasonal activation of the HPG axis. TRPA1, a target of THRB identified by DAP-seq, was sensitive to photoactivation and exhibited differential expression levels between short- and long-day conditions. CONCLUSION: Our data suggest that trans effects were the main factors affecting gene expression during the seasonal activation of the HPG axis. This study could lead to further research on the seasonal reproductive behavior of birds, particularly the role of MBH in controlling seasonal reproductive behavior.

Black soldier fly (Hermetia illucens) larvae meal improves quail growth performance.

The aim of the present study was to determine the nutritional value of black soldier fly (BSF) larvae meal for quail (experiment I) and the dose-response effects of BSF levels on growth performance, relative organ weight, and body composition of growing quails (experiment II). In experiment I, 100 35-day-old quail were distributed in a completely randomized design, with two treatments (reference and test diet) and 10 replicates. The experimental period consisted of 5 days of adaptation, followed by 5 days of total excreta collection. The experimental feed consisted of a reference diet and a test diet formulated with 850 g/kg reference diet and 150 g/kg BSF. In experiment II, 1000 1-day-old quail were distributed in a completely randomized design, with five dietary levels of BSF (0, 25, 50, 75, and 100 g/kg). At 42 days of age, birds were slaughtered, and the relative organ weight and body composition were determined. Apparent metabolizable energy values corrected for nitrogen retention of BSF meal were 13.8 MJ/kg. Across the starter (1-14 days) and overall period (1-42 days), increasing BSF levels had a quadratic effect on body weight and body weight gain. Feed conversion ratio was quadratically affected during the starter phase and linearly reduced over the overall period. Additionally, the BSF levels linearly decreased the small intestine's relative weight at 42 days and had a quadratic effect on the rate of protein deposition. We concluded that the inclusion of 100 g/kg BSF meal improves feed conversion ratio for growing quail.

Differential diagnosis of Eimeria species in farmed Japanese quails (Coturnix japonica).

Similarly to poultry industry, coccidiosis may cause significant economic losses also in the commercial quail industry, an emerging sector undergoing uneven development around the world. Although scant and mostly dated, the available literature reports detailed morphological and morphometric features of both oocysts and sporocysts of the Eimeria species hitherto recognized in Japanese quails, i.e. E. tsunodai, E. uzura, E. bateri, and E. fluminensis. Mixed infections are very common in the field and require an accurate differential diagnosis of diverse species of coccidia, identifying the highly pathogenic ones, in particular E. tsunodai (localized in the caeca), and E. uzura (localized in both caeca and small intestine). This goal is hampered by time-consuming laboratory procedures involving highly qualified staff and facilities, and poorly compatible with routine management practices in farmed quails. A supplemental difficulty is represented by the lack of nucleotide sequences available in GenBank. To overcome these issues, copromicroscopic and molecular analyses (amplifying the 18S rRNA region, and the internal transcribed spacers regions ITS1-5.8rRNA-ITS2) were performed on oocysts populations separately isolated from pools of 12 caecal and 12 cloacal contents collected from 240 naturally infected laying Japanese quails. Data on morphological and morphometric features of 1,000 sporulated oocysts were statistically compared, demonstrating the presence of different Eimeria species colonizing the 2 intestinal tracts. This result was also confirmed by PCR and phylogenetic analysis of the 18S rRNA gene. Overall results allowed to hypothesize the presence of E. uzura in our Japanese quails. Although a certain identification at species level was not obtained, the present study demonstrates that reasonable turnaround times of monitoring procedures performed on Japanese quail farms, shedding light on the in vivo and post-mortem differential diagnosis of coccidiosis can be achieved, and provide obvious benefits in disease understanding and control.

Impact of Dietary Probiotics on the Immune and Reproductive Physiology of Pubertal Male Japanese Quail (Coturnix coturnix japonica) Administered at the Onset of Pre-Puberty.

Fertility in males is dependent on the proper production of sperms involving the synchronization of numerous factors like oxidative stress, inflammatory processes, and hormonal regulation. Inflammation associated with oxidative stress is also known to impair sperm function. Nutritional factors like probiotics and prebiotics have the potential benefits to modulate these factors which may enhance male fertility. In the present study, immature male Japanese quail at the beginning of 3rd week were administered with Lactobacillus rhamnosus (L), Bifidobacterium longum (B), and mannan-oligosaccharides (M) through dietary supplementation in individual groups as well as in combinations like LB and MLB. Markers of oxidative stress including SOD and catalase were examined by native PAGE; inflammatory biomarkers (IL-1ß, IL-10, and NFκB), apoptotic markers (caspase 3 and caspase 7), steroidal hormones, and their receptors estrogen receptor alpha (ERα) and beta (ERß) were assessed in testis. The study reveals that dietary supplementation of 1% L, B, and M in combination significantly and positively increases the overall growth of immature male quail specifically testicular weight and gonadosomatic index (GSI). Furthermore, significant improvement in testicular cell size; increased steroidal hormones like testosterone, FSH, and LH levels; increase in SOD, catalase enzymes; decrease in apoptotic factors Caspase 3, Caspase 7 and immune system strength observed indicated by a decrease in expression of IL-1ß, NFκB; and increase of IL-10 in testis when LBM was used in combination. These variations are attributed to the increase in testicular estrogen receptors alpha and beta, facilitated by the neuroendocrine gonadal axis, ultimately leading to improved male fertility. It can be concluded that the dietary supplementation in combination with L, B, and M enhances male fertility in immature quail by increased expression of estrogen receptors via gut microbiota modulation. It also sheds light on the potential use of these nutritional factors in avian species as therapeutic interventions to overcome low fertility problems in quail thereby benefitting the poultry industry.

Metabolic Rate and Egg Production in Japanese Quails Can Be Predicted by Assessing Growth Parameters of Laying Hens.

The aim of the current study was to assess the female metabolic rate and test the hypothesis that there is a relationship between the egg productivity of Japanese quails from eight breeds and their morphometric, or growth, parameters. Parameters measured were body weight (B), volume (V), and surface area (S), as well as the metabolism level expressed by the ratio S/V. The collected egg performance traits were as follows: the number of eggs produced (N), the average egg weight (W), and the total egg mass (M) (i.e., N multiplied by W). To measure the S and V values, a novel technique was developed that takes into account the similarity of the quail's body to an ellipsoid. An analysis of the relationships between productivity indicators allowed us to introduce a new index called the metabolic index, B·S/V, based on all three main growth parameters in quails. Using the values of this index, we were then able to judge indirectly the level of quails' egg productivity. We went on to assess the N, W, and M values, not only depending on the size of the bird's growth parameters but also according to the degree of their changes during quail growth. These changes were expressed as the slope angles of trend lines describing the growth process data. This approach produced more accurate results for predicting the egg productivity in terms of W and M.

The effect of incorporating dietary green seaweed (Ulva sp.) on growth performance, blood parameters, and carcass and meat quality characteristics of Jumbo quail.

Seaweeds are functional aquatic plants that can be used in Jumbo quail (Coturnix sp.) feeds as sources of phytochemicals and nutrients. However, no studies have investigated the feed value of green seaweed (Ulva sp.) meal (SM) for the Jumbo quail. Thus, the impact of different dietary inclusion levels of SM on productive traits, serum biochemistry, haematology, visceral organ sizes, carcass features, and meat quality attributes in Jumbo quail was investigated. In a completely randomised design, one-week-old quail (n = 385; 67.7 ± 3.44 g body weight) were allotted to five treatments, with seven replicate pens (experimental unit). The treatments were produced by including 0 (SM0), 20 (SM20), 40 (SM40), 60 (SM60) and 80 g/kg (SM80) of green SM in a commercial grower diet. Regression results showed no linear or quadratic effects (P > 0.05) to different levels of SM for average weekly feed intake, overall weight gain, haematological indices, internal organs, carcass features, and meat quality characteristics of the birds. However, incorporating SM up to 80 g/kg in the diet linearly reduced overall gain-to-feed ratio (G:F) [R2 = 0.282; P = 0.0001] and slaughter weights [R2 = 0.159; P = 0.026]. Treatment SM80 promoted (P < 0.05) higher feed intake than diet SM60 in weeks 3, 4 and 5, but were comparable to the control treatment in weeks 4 and 5. Birds fed with diets SM0 and SM20 had higher (P < 0.05) overall weight gain than birds fed with diet SM60. Diet SM80 resulted in lower (P < 0.05) overall G:F (0.250) than diet SM0 (0.277). Higher slaughter weights were observed on SM0 and SM20 groups than the SM60 group. We concluded that the use of dietary green SM up to 80 g/kg in Jumbo quail feeds compromises gain-to-feed ratio and slaughter weights but not physiological and meat quality attributes.

The Histopathological and Oxidative Stress Profiles in Japanese Quails (Coturnix japonica) Induced by Dietary Lead.

In their native habitat, avians are exposed to external toxicity factors, the most prominent of which are chemical lead compounds that threaten human and animal health. The goal of this investigation was to estimate the adverse effects of lead acetate (Pb(CH3COO)2 (H2O)3) on the health status of Japanese quail (Coturnix japonica). 18 adult male Japanese quails (Coturnix coturnix japonica) were employed in this investigation. After two weeks of acclimatization, the birds were randomly divided into three groups: the control group received no Pb+2, the Low Dose Group received 50 mg/kg of Pb+2 as lead acetate Pb(CH3COO)2 (H2O)3 in the diet, and the High Dose Group received 100 mg/kg of Pb+2 as lead acetate Pb(CH3COO)2(H2O)3 in the diet, for 30 days. Results showed that the Pb bioaccumulation was recorded at the highest values in the liver compared with the kidney, and as expected, the ranges of the lead accumulation were significantly higher in the animals who received 100 mg/kg Pb compared with animals who received 50 mg/kg Pb and the control group. In the high dose group, serum content showed significantly increased levels (P≤0.05) of aminotransferase enzymes (ALT and AST ), glucose, creatinine, and uric acid levels compared to other groups, while antioxidant enzymes (CAT, GSH, and GSH-PX) levels in the liver and kidney were significantly reduced (P≤0.05). The results showed that the MDA appeared to be significantly increasing (P≤0.05) in the high dose group compared to the other groups. Compared to the low dose and control groups, the high dosage group produced substantial histological abnormalities in the liver and kidney.

Reconstructing migratory network nodes to improve environmental management and conservation decisions: A case study of the common quail Coturnix coturnix as a biosensor.

Public health risks are related to environmental management practices, and are essential to the understanding of ecosystem dynamics. The expansion of urbanized areas affects migratory bird networks and can impact the population sizes of migratory species and, in parallel, increase the risk of diseases carried by migratory species spreading into urban areas. Taking the European population of the common quail as a case study, we reconstructed its migratory network between Europe and the Maghreb using quail recoveries from the Italian Bird Ringing Scheme. We showed that soils at the central European migratory node have been degraded through urbanization and reforestation, decreasing the number of successful migrations over this area. Conceptual models incorporating the One Health approach, natural and social capital, landscape infrastructure, and ecosystem services could explain the relationships between climate warming and extensively developed, intensively developed, and urbanized ecosystems. Failed migratory flights of quail over central Europe highlight not only the problems of infrastructure design and their impact on ecosystems services, but also on One Health parameters. The damage to migratory network nodes presents a global threat to biodiversity and can increase the spread of diseases. To address this challenge we propose: i) improvements in land quality; ii) transboundary migration monitoring programmes; and iii) management plans for migratory birds - the overall aim being to optimize infrastructures to improve the quality of human life. Lessons drawn from a better understanding of the migratory networks of quail in relation to different ecosystems provide useful tools to improve infrastructure management and political decision making processes.

Potential of Full-Fat Silkworm-Based Diets for Laying Quails: Performance and Egg Physical Quality.

The present research was conducted to determine the optimal inclusion level of full-fat silkworm chrysalis meal (SWM) into laying quails' diets, focusing on performance traits and egg physical quality. A total of 240 31-day-old female Japanese quails were randomly assigned to four dietary groups (12 replicates/treatment; 5 quails/replicate); quails were initially fed a standard commercial diet for pullets until 63 days of age. When oviposition started, the experimental groups received the following diets: a conventional corn and soybean-based diet (control diet-C) and three other diets, including 4%, 8%, or 12% of full-fat SWM (SWM4, SWM8, SWM12, respectively). Experimental diets were provided until quails reached 119 days of age. Birds displayed satisfactory productive performance throughout the trial. SWM12 and SWM8 had higher (p < 0.001) egg production but also a higher feed conversion ratio compared to C. At the end of the trial, the eggs edible portion increased, and shell weight decreased with increasing the SWM dietary inclusion level (p < 0.001). At the same time, SWM12 displayed an increase in albumen pH (p < 0.05), even though in the normal range for quail egg. Overall, full-fat SWM (up to 12%) can be considered a promising feed ingredient for laying quails, although higher inclusion levels (>8%) require special attention because SWM also contains anti-nutritional factors.

The Effect of In Ovo Administration of Rosemary Essential Oil on Hatchability, Relative Hatching Weight, and Embryo Mortality Rate in Japanese Quail (Coturnix coturnix japonica).

This study aimed to determine the effects of air sac injection of rosemary essential oil at different concentrations in ovo in quail eggs on hatching rate, relative chick weight at hatching, and embryonic mortality rate. A total of 1060 Japanese quail eggs were divided into four groups: negative control (non-injected), positive control (30 µL sterile distilled water/egg), and two treated groups with 1 and 3 µL oil/egg, respectively. The concentration of 3 µL/egg showed a toxic effect on embryonic development, as revealed by the significantly (p = 0.015) higher post-injection mortality rate (18.21%) compared to 1 µL/egg with 8.3%. Furthermore, hatchability was significantly increased (p = 0.0001) with 1 µL/egg compared to 3 µL/egg with 69.1% and 44.48%, respectively. No significant difference was observed between the concentration of 1 µL/egg and the control groups (p = 0.822). Both l and 3 µL essential oil/egg significantly enhanced (p = 0.0001) relative chick weight at hatching by 67.14% and 70.32%, respectively, compared to the control groups. In conclusion, injecting eggs with 1 µL oil/egg showed positive effects both on hatching and relative chick weight. The concentration of 3 µL/egg was revealed to be toxic, with dramatic effects on embryonic survival.

Effect of the dietary inclusion of Camelina sativa cake into quail diet on live performance, carcass traits, and meat quality.

The present research studied the effect of the dietary inclusion of 3 different camelina (Camelina sativa (L.) Crantz) cakes on the live performance, slaughter traits, and breast meat quality of broiler quails (Coturnix japonica). With this purpose, a total of 480 fifteen-day-old broiler quails of both sexes were allocated to 48 cages (12 replicates/treatment, 10 quails/replicate) and received 4 dietary treatments: a control diet (Control), and 3 diets containing 15% of 1 commercial cultivar (Calena), and 2 improved lines (Pearl: low linoleic acid; Alan: low glucosinolates). During the experiment, individual live weight (LW) and cage feed intake were recorded to calculate body weight gain (BWG) and feed conversion ratio (FCR). At 35 d of age, quails were slaughtered, and carcasses were weighed and dissected to compute yields. On breast (pectoralis major muscle) the measurements and analyses considered ultimate pH, L*a*b* color values, proximate composition, oxidative status, cooking loss and WBSF toughness. Broiler quails receiving diets with camelina cakes exhibited mortality and health status similar to the control. However, growth performance was impaired in camelina-fed groups, especially for Calena (P < 0.05). Overall LW and BWG were slightly lower, whereas feed intake was slightly higher in camelina-fed groups compared to Control (P > 0.05). Therefore, higher FCR was recorded for camelina-fed groups compared to Control (P = 0.0004). Moreover, breast meat from Calena treatment displayed higher water (P = 0.0170), and lower lipid (P = 0.0051) contents compared to those of the Control group, while protein and ash content remained unaffected. Heme-iron content and oxidative status of breast meat were not influenced by the dietary incorporation of camelina (P > 0.05). The research outcomes indicated that camelina cakes can be used as an alternative feed ingredient for broiler quails' diets, without compromising carcass yields and meat quality. However, as 15% dietary incorporation worsened live performance, the ideal camelina cake inclusion level should be thoroughly investigated as well as a parallel research effort into further reducing glucosinolates content of camelina.

Maximum limit of sensible heat dissipation in Japanese quail.

Surface temperature can be used as a tool for calculating sensible heat transfer. However, it needs to be associated with air temperature to identify the direction of heat flow (gain or loss). This study quantified sensible heat transfer in Japanese quail as a function of operative temperature. The meteorological variables were air temperature, relative humidity, and black globe temperature. Quail surface temperature was measured on 50 adult Coturnix coturnix japonica individuals 270 days old during 8 days by using a thermographic camera. The data were analyzed by the least-squares method to assess the effects of sex (male and female), period of the day (morning and afternoon), and body region (head, body, and feet). Quail surface temperature was strongly correlated with operative temperature. The total sensible heat flow was 64.02 W m-2. The morning period had a mean operative temperature of 22.48 °C, providing a higher gradient between air and quail temperature and thereby producing a higher heat flow (82.19 W m-2). In the afternoon, the heat transfer was lower (45.70 W m-2) because the operative temperature was higher (30.84 °C). Comparison between sexes showed that heat transfer was higher in females (67.37 W m-2) than in males (60.53 W m-2). The head served as an important thermal window, with a heat transfer of 78.24 W m-2, whereas the body and feet had a transfer of 56.80 W m-2. Heat transfer by sensible mechanisms was quantified in Japanese quail. Heat transfer depended greatly on ambient temperature. When the operative temperature was below 28 °C, sensible mechanisms were efficient in dissipating heat to the environment. When the ambient temperature exceeded 29 °C, quail could not effectively dissipate heat to the environment through sensible mechanisms. At 30 °C and above, heat loss shifted to heat gain, causing thermal stress in Japanese quail.