Histological and histochemical studies on the oviduct microcirculation of the laying Japanese quail (Coturnix japonica)

The health of oviduct circulation is very important for normal egg production. The present work describes the histology and histochemistry of vessels of different types on the oviduct of quail. Arteria, venae and lymphatics of the oviduct were described clearly. In addition, special vascular elements were observed presenting circular, longitudinal and oblique smooth muscle fibres on the blood vessel wall. Glomus cells were observed at typical glomus vessels, atypical glomus vessels and on the wall of some of arteria and arteriolae. Also, spirally oriented blood vessels were observed. Dark brown pigment was detected in the wall of arteria, venae, lymphatics and the special types of blood vessels.     

Haematology of the Japanese quail (Coturnix coturnix japonica)

Blood samples from 30 2‐week‐old unsexed chicks, 25 adult males, 30 non‐laying hens and 19 laying hens were examined to characterise haematological norms in Japanese quail (Coturnix coturnix japonica) under various physiological conditions such as age, sex and laying. Young quail had significantly lower erythrocyte counts, packed cell volumes, haemoglobin content, mean corpuscular haemoglobin concentrations, numbers of thrombocyte::, percentages of lymphocytes and plasma protein levels than did the adult males and the non‐laying hens. The total leucocyte count of the young birds was not significantly different from that of the males and just different from that of the non‐laying hens. The young birds also showed a higher mean corpuscular volume, mean corpuscular haemoglobin and percentages of heterophils and monocytes in comparison with the adult males and the non‐laying hens. A comparison between males and females showed that males had a higher erythrocyte count, packed cell volume and haemoglobin content and a lower concentration of plasma proteins than the adult females. Excepting for an elevated relative count of eosinophils, no influence attributable to laying was observed.     

Experimental studies on Marek's disease in Japanese quail (Coturnix coturnix japonica)

Day-old quails experimentally infected with Marek's disease (MD) virus of quail origin developed lymphoid tumors. The severity of the disease increased considerably with serial passage. Tumor transplants could be made with cells derived from gross tumors in skeletal muscles, spleen cells, and blood from MD-affected quails. After five to six serial transplants, the tumor could not be transplanted further. Marek's disease tumor-associated surface antigen (MATSA) was demonstrated in lymphoid cells of spleen and peripheral blood lymphocytes of MD-affected quails. The MATSA of quail differed from the MATSA of chicken. Chickens were susceptible to MD virus isolated and propagated in quails.     

Ultrastructural study of ochratoxicosis in quail (Coturnix coturnix japonica)

Ultrathin sections of liver and kidney from 11-week-old quail fed, from day-old, ochratoxin A (OA) (mixed in the diet at levels of 4 and 8 ppm) were examined in the electron microscope. Pathological changes in the kidneys were limited to the proximal convoluted tubules (PCT) and glomeruli. In the PCTs, abnormal mitochondria and excessive numbers of lipid droplets were the principal findings with glomeruli showing thickened basement membranes. Swollen mitochondria and variable glycogen deposition were the chief features present in the livers. It is suggested that OA is more hepatotoxic in quail than in broilers, as well as being nephrotoxic.     

An immunohistochemical study of ovarian follicle histogenesis in the early post-hatch Japanese quail (Coturnix coturnix japonica)

The early post-hatch development of immunoreactivity to vimentin, desmin, smooth muscle actin (SMA) and laminin, in relation to follicle histogenesis, was described in this study. Ovigerous cords in day old quails contained pre-granulosa cells and oocytes. Pre-granulosa cells at the cortico-medullary junction were vimentin immunopositive. A laminin immunopositive basement membrane and desmin immunopositive mesenchymal cells lined the ovigerous cords. Ovigerous cords in 3-day-old quails contained developing primordial follicles, the vimentin immunopositive pre-granulosa cells of which were partially encircled by a basement membrane and desmin immunopositive mesenchymal cells. In 5- to 7-day-old quails, ovigerous cords formed an outer cortical region, while primordial follicles formed the inner cortical region. Early pre-vitellogenic follicles were present in 9- to 13-day-old quails. Underlying the granulosa cells of these follicles was a laminin immunopositive basement membrane and a layer of desmin immunopositive thecal cells. Early and late pre-vitellogenic follicles dominated the ovary in 15- to 17-day-old quails. The thecal layer in these follicles was desmin immunopositive, but SMA immunonegative. The results of the study have shown that the process of primordial follicle development in the Japanese quail is similar to that reported in mammals. The study suggests that in the quail pre-granulosa cells originate predominantly from the medulla. The study has shown that, in the Japanese quail, thecal cells are derived from desmin immunopositive mesenchymal cells lining the ovigerous cords.     

Characterization of the cathelicidin cluster in the Japanese quail (Coturnix japonica)

The Japanese quail has several advantages as a low‐fat meat bird with high immunity against diseases. Cathelicidins (CATHs) are antimicrobial peptides that play an important role in innate immunity. The aim of this study was to characterize the CATH cluster in the Japanese quail (Coturnix japonica). The Japanese quail CATH (CjCATH) cluster, contains four CATH genes, as in the chicken. The coding sequences of CjCATHs exhibited >85.3% identity to chicken CATHs. The predicted amino acid sequences of the four CjCATH genes contained the cathelin‐like domain characteristic of CATH proteins. Polymorphisms were detected in the open reading frames (ORFs) of all CjCATH sequences. Two amino acid substitutions were observed in the antimicrobial region of the mature peptide of CjCATH2, and predicted to influence peptide function. CjCATH1 is expressed in lung, heart, bone marrow and bursa of Fabricius (BF). CjCATH2 is expressed in bone marrow. CjCATH3 is expressed in lung, heart, bone marrow, BF, tongue and duodenum. CjCATHB1 is expressed in bone marrow and BF. This study is the first to characterize CATH genes in the Japanese quail, and identifies novel antimicrobial peptide sequences belonging to the cathelicidin family, which may play a role in immunity in this species.     

The timing of oviposition and ovulation in the quail (Coturnix coturnix japonica)

An extensive series of experiments was performed to assess the common Coturnix quail as a laboratory bird for research on ovulation. The results indicate that the timing of the sequential events of ovulation, egg formation and lay in Coturnix is sufficiently constant to permit access to the physiological processes which determine ovulation and to provide convenient means for assessment of results. Special problems of method and limitations in the use of the quail are discussed. Differences in the timing of sequential ovulations in chickens and Coturnix are described. It is concluded that Coturnix will be a valuable subject for comparative studies on ovulation in birds.     

Hypocholesterolemic effect of karaya saponin in Japanese laying quails (Coturnix coturnix japonica)

The effect of karaya saponin supplementation on the serum and egg yolk cholesterol and fatty acid composition in egg yolk were investigated in Japanese quails. A total of 80 Japanese quails aged 5 weeks were equally divided into four groups of 20. Four levels (0, 25, 50 and 75 mg/kg feed) of karaya saponin were included in the basal diet and experiment was lasted for 6 weeks. The cholesterol fractions in the egg yolk and serum were measured by enzymatic assay, and the fatty acid composition in egg yolk was determined by gas chromatography. The results revealed that the supplementation of 75 mg/kg karaya saponin significantly reduced (p < 0.05) cholesterol and triglycerides concentration in serum and egg yolk. High-density lipoprotein-cholesterol was increased, low-density lipoprotein-cholesterol and the atherogenic index were decreased (p < 0.05) by the dietary supplementations. Hepatic cholesterol was reduced (p < 0.05) by the 25 mg/kg karaya saponin. A higher degree of yolk colour was improved (p < 0.05) when 75 mg/kg saponin was supplemented in the diet. The concentration of polyunsaturated fatty acids (PUFA) in egg yolk was increased (p < 0.05) in a dose-dependent manner in quails fed the supplemented diet than the control diet. The ratio of PUFA to saturated fatty acids in egg yolk was improved (p < 0.05) by 75 mg/kg feed karaya saponin-supplemented diet. Therefore, the dietary supplementation of 75 mg/kg karaya saponin may be a feasible means of producing quail eggs with lower cholesterol and higher PUFA content for health conscious consumers.     

Duration and recovery of fertility in Japanese quail (Coturnix coturnix japonica)

Duration and recovery of fertility were investigated in the course of a long‐term project concerning inbreeding depression of fitness and other traits in Japanese quail. In two trials pair matings were made in the four possible combinations between mature random bred (R) and inbred (I) males and females.

Analysis of both trials was limited to (i) birds that were fertile in at least one previous hatch and (ii) matings that produced at least one fertile egg on or after the second day following removal of males. With these restrictions differences between mating types were not statistically significant. R×R matings had a longer duration and a faster recovery of fertility than the other mating types. Slower recovery of fertility in matings involving inbred birds may in part be due to reduced mating frequency, especially of inbred males.

Mean duration of fertility in all data analysed was 6.3 days after removal of males from pair cages. Upon remating the first fertile egg was laid after an average of 3.5 days. Ageing effects of sperm significantly decreased hatchability of fertile eggs.

Comparison with other species of birds shows the mean duration of fertility in Japanese quail to be about as short as that of ducks and geese, and about one‐half and one‐fourth as long as that of chickens and turkeys, respectively.     

The effect of different high‐fat diets on erythrocyte osmotic fragility,growth performance and serum lipid concentrations in male,Japanese quail (Coturnix coturnix japonica)

Poultry diets are formulated with additional animal fat or vegetable oils to improve growth rate and feed conversion efficiency. High‐fat diet feeding in rats and fish has been shown to result in alterations in the phospholipid composition and cholesterol content of the erythrocyte membrane, in turn affecting erythrocyte osmotic fragility. In contrast, the few studies performed using high‐fat diet feeding in avian species show no changes in erythrocyte osmotic fragility. This study made use of the Japanese quail as no data exists on investigation of this species with respect to high‐fat diet feeding and erythrocyte osmotic fragility. Fifty‐seven male quail were randomly divided into six groups and fed either a standard diet (commercial poultry feed) or one of five high‐fat diets (commercial poultry feed with 22% of either coconut oil, lard, palm oil, soya bean oil or sunflower oil on a weight/weight basis) for 12 weeks. All birds on the high‐fat diets were significantly heavier (p < 0.05) after the 12‐week feeding period, than when commencing the dietary intervention. Serum triglyceride concentrations of birds in all high‐fat diet groups were significantly lower (p < 0.05) than birds in the standard diet group, whereas only birds in the palm oil group had significantly lower (p < 0.05) serum cholesterol concentrations compared to the standard diet group. Fragiligrams of erythrocytes from birds in the various dietary groups were similar. High‐fat diet feeding with different types of additional fat did not affect the osmotic fragility of the quail erythrocytes. Feeding quail high‐energy diets of varying degrees of fatty acid saturation was well tolerated and did not seem to affect the overall health status of the birds. Resistance of avian erythrocytes to modification by excess dietary fat may be a general characteristic of avian erythrocytes.     

Carcase characteristics of quail (Coturnix coturnix japonica) slaughtered at different ages

1. The present study was conducted to evaluate the relationship between slaughter ages and carcase characteristics of Japanese quail.

2. Chicks were slaughtered at 5, 6, 7, 8 and 9 weeks of age. Carcase yield, carcase parts weight, weight of liver, heart, gizzard and alimentary tract were obtained. Protein, fat, dry matter and ash contents of meat were analysed for each sex.

3. Body weight and eviscerated weight were affected by age. Age had no significant effect on the weight of liver, alimentary tract, gizzard and heart. Age had first and second order polynomial effects on breast weight and relative leg weight. Meat compositions of leg and breast were significantly affected by age.     

Immunohistochemical and ultrastructural characterization of the ovarian surface epithelium of Japanese quail (Coturnix japonica)

Contrary to humans, most ovarian tumors in other species do not arise from the ovarian surface epithelium but are of follicular‐, stromal‐ or germ‐cell origin. One of the few species where ovarian cancer arises from the ovarian surface epithelium (OSE) is chicken (Gallus domesticus). Little is known about the morphology of the OSE in other avian species. In our study we analyzed the OSE morphology of Japanese quail (Coturnix japonica) using ultrastructural and histochemical techniques. Carbohydrate residues have been studied by using a panel of fluorescein isothiocyanate labeled lectins. Japanese quails are commonly used animal models in biomedical research as their housing is comparatively inexpensive and they show a short generation interval. Our ultrastructural and histochemical results demonstrate that the quail ovarian surface epithelium shows characteristic features which resemble the epithelia of both chicken and human. Additionally, the ovarian surface epithelium of the Japanese quail contains cytokeratin as well as vimentin intermediate filaments in their cytoplasm. Therewith and among other parts the quail OSE shows many characteristic features also seen in those of humans, which may qualify quail's ovary as a potential animal model for human ovarian carcinomas.     

Histological and histochemical studies on the lingual, preglottal and laryngeal salivary glands of the Japanese quail (Coturnix coturnix japonica) at the post-hatching period

The postnatal development and histochemistry of mucins of the lingual, preglottal and laryngeal glands in the quails were investigated by means of light microscopy using specific staining for complex carbohydrates. In this study, the tongues were taken from female and male quails from day 1 to day 60 after hatching. The salivary glands in quail's tongue comprised the lingual gland, with lateral and medial (paraentoglossal gland) portions that differ in morphology and histochemical staining, and the preglottal gland, with two lateral portions and one medial portion. The medial portion of the preglottal gland, which extended to the row of the laryngeal papillae on each side of the glottis, was described as the laryngeal gland. The salivary glands were present at hatching and their cells were functionally mature and secreted mucins. In quail of all ages, the histochemical reactions revealed that the cytoplasms of the secretory cells of the preglottal, laryngeal and paraentoglossal gland (medial portion of lingual gland) contained sialomucins and weakly sulphated epithelial mucins. Neutral mucins were absent in the paraentoglossal gland, while a small amount of neutral mucins was present in other glands. The mucins with vicinal diol groups, sialomucins and weakly sulphated epithelial mucins were mixed within the secretory cells of all the glands. All the histochemical reactions were restricted to the supranuclear regions of the secretory cells within the lateral portion of the lingual gland. In conclusion, the contents of mucins in the lingual, preglottal and laryngeal glands varied between different age groups, however, no differences in the glands' histochemistry between male and female quails were observed.     

CXCL14-like immunoreactivity in somatostatin-producing cells of the Japanese quail (Coturnix japonica) pancreas

This study examines chemokine CXCL14-like peptide distribution in the Japanese quail (Coturnix japonica) pancreas using a specific anti-human CXCL14 antibody. CXCL14-immunoreactive cells were observed in the pancreatic islet peripheral region. The staining was abolished after pre-absorbing the antibody with recombinant human CXCL14. CXCL14-immunoreactive cells were immuno-positive for somatostatin, but not glucagon and insulin. CXCL14 secreted from somatostatin-producing cells might participate in insulin secretion modulation together with somatostatin. In addition, CXCL14 might participate in glucose homeostasis in co-operation with somatostatin and growth hormone.     

Influence of animal age on body concentrations of minerals in Japanese quail (Coturnix japonica)

Mathematical modelling of the relationships between mineral inputs and outputs would enable the prediction of mineral requirements of poultry under a wide range of conditions. To establish the feasibility of possible modelling of mineral requirements, the current study aimed to describe the individual mineral concentrations of whole bodies of quail over the life cycle from hatching to 70 days of age. Quail were reared indoors without any restrictions that could limit growth. Sampling of birds (n = 6–18) was carried out at 0, 3, 7, 14, 21, 35, 49 and 70 days after hatching. Freeze‐dried samples of whole bodies (digestive contents removed) were analysed for ash, and macrominerals (calcium, magnesium, phosphorus, potassium, sodium) and microminerals (copper, iron, manganese, nickel, selenium, zinc). Ash concentration followed a curvilinear trend, with a maximum of 101.7 g/kg dry matter at 32.77 days. Individual mineral concentrations, expressed as a proportion of ash, were fluctuating over time, with the most prominent changes at 3 days and again at either 14 or 21 days. Dissimilar patterns in individual mineral concentrations resulted that ratios between minerals followed inconsistent patterns over time. Although mineral contents in absolute quantities can be described through modelling over the entire life cycle of the bird, it can be concluded that variable concentrations of individual minerals could complicate further model development.     

Genetic parameters of slaughter and carcase traits in Japanese quail (Coturnix coturnix japonica)

1. Genetic parameters of slaughter and carcase traits were estimated for 5-week-old Japanese quail reared under the one-to-one sire and dam pedigree recorded system. Data were analysed using restricted maximum likelihood (REML) with relationship matrix. Records of 1244 animals from 119 sires and 156 dams were analysed. 2. An individual animal model was used which had the animals' genetic effect as the only random factor. Heritability and standard errors of slaughter, cold carcase, breast, leg, wing, others, liver weights and dressing percentage were 0·40 ± 0·07, 0·55 ± 0·07, 0·58 ± 0·07, 0·54 ± 0·07, 0·49 ± 0·07, 0·42 ± 0·06, 0·13 ± 0·04 and 0·21 ± 0·05 respectively. Moderate to high heritability for most of the studied traits suggested that selection to increase or decrease these traits will be successful. 3. The strongest genetic correlation was found between slaughter, carcase and breast weights (0·97-0·87). These high genetic correlations provide an opportunity to select for breast weight on the basis of 5-week weight. 4. It can be concluded that carcase weight and 5-week weight of quail can be included in a selection index to increase the weights of valuable carcass parts.