Most birds have visual sensitivity to ultraviolet (UV) wavelengths, and this sensitivity appears to play a role in their colour vision. Artificial lighting is normally deficient in UV wavelengths. Hence, there may be welfare implications for captive birds kept under such lighting. We investigated whether the absence of UV wavelengths during rearing adversely affects Japanese quail (Coturnix coturnix japonica). We also investigated the short-term effect of switching from UV-containing to UV-deficient lighting, and vice versa. Stress was assessed by monitoring behaviour and plasma corticosterone levels. We did not detect any significant difference in these variables between birds reared either with or without UV. We conclude that rearing quail in an absence of UV does not appear to have a significant impact on their welfare, as measured using these indicators.

Around 10% of all table eggs number in the world come from quail and their meat represents about 0.2% of the global poultry production. The domestic quail population involved in production of meat and eggs represents around 11.8% of all productive birds, placing them second after laying hens. China, Spain, France, Italy, Brazil, the USA and Japan are global leading countries in quail farming. Contemporary domesticated Japanese quail, widely used in agricultural practice, originate from wild Japanese breeds (C. japonica). The wild Asian quail is similar to common quail (Coturnix coturnix) and until recently, was accepted as its subspecies (Coturnix coturnix japonica). In the scientific literature, several names for domestic quail are available, so readers can easily become confused as to which species is really meant - wild, domesticated or common quail. In order to avoid confusion of names and to emphasise changes resulting from domestication, the term ‘domestic quail’ and its corresponding Latin name Coturnix japonica domestica is more appropriate. Within the EU legal framework, domestic quail should be included in parallel to other domestic fowl species.

The current study investigated the influence of selection for body weight (BW) on growth curve parameters in two lines of Japanese quail through a mixed model approach. Live BWs of 1400 Japanese quail were recorded at 3-day intervals from hatching to 42 days of age. Birds were distributed equally across lines (selected and control) and sexes (male and female). The asymptotic weight parameter (β0) values were always higher in Gompertz than Richards models in both lines. The values of β0 were higher in the selected than control lines and in females than males across models. Differences were found in the inflection point for age and weight across lines and sexes. Values of the growth rate parameter (β2) ranged from 0.06 to 0.10 in both models, favouring males over females in both lines. Lower weights at the inflection point of both models were observed in the control line. Determination coefficient (R2) of both models in different genetic groups and sexes was similar. Mean square error (MSE) values of the Gompertz model were lower for females in selected v. control lines. In contrast, MSE values of the Richards model were lower for selected males v. control males. According to the criteria of choice (highest R2 and lowest MSE, Akaike information criterion and Bayesian information criterion), the Richards model was considered the best fitting model for the growth data of males, while the Gompertz model was the best for growth data of female quails in both lines.

The present investigation was carried out to estimate the effects of genotype and sex on growth and laying performance and assess the variations in plasma constituents in the tested genotypes and their relations with productive traits after four generations of selection. Data of growth and laying performance on 1440 females and males of Japanese quail were taken from the three quail genotypes: maternal (MG), long shank length (LSG28) and control (CG) genotypes. Genotype significantly affected all studied growth productive traits, favouring selected genotypes. The LSG28 surpassed MG in total protein, albumin (Alb), globulin (Glob), triglycerides and Alb/Glob ratio and lowered both cholesterol and total lipids (TL). Sex significantly favoured females, which had higher body weight, longer shank length at 35 days of age and higher body weight gain during the period from 1 to 35 days of age. Females showed significantly higher concentrations of both Alb and TL than males. The MG exceeded LSG28 in fertility and hatchability per cent. Correlations for both growth and productive traits with plasma constituents revealed inconsistent trends in either magnitude or direction. Four generations of selection resulted in substantial phenotypic improvements in most growth and productive traits, as well as plasma constituents studied in LSG28, and favoured MG in maturity, days needed to produce the first ten eggs, higher egg production per cent and heavier egg mass.

This study aimed to investigate the effect of supplemental camphor on the performance and immune functions of Japanese quail by feeding graded levels (0 (control), 250, 500, 750, 1000, 5000 or 10 000 ppm) of camphor during a 42-day feeding trial. In all, 280 1-day-old quail chicks were randomly assigned into 28 cages of 10 chicks each with separate feeders. The results clearly demonstrated that camphor did not have a significant effect on BW, BW gain, total experimental average daily feed intake, feed conversion ratio, internal organ relative weights and biochemical parameters such as uric acid, albumin, total protein and triglyceride; however, plasma cholesterol concentration was significantly different in a linear manner, in which 500 ppm of camphor resulted in a lower level of cholesterol. Alternatively, greater concentrations of glucose and high-density lipoprotein (HDL) were also found in 5000 and 1000 ppm of camphor groups, respectively. Cellular responses to the phytohaemagglutinin-P and 2,4-dinitro 1-chlorobenzene skin test were not influenced by dietary camphor. Humoral responses to secondary sheep red blood cells, avian influenza virus (AIV) and Newcastle disease virus (NDV) immunisations were positively influenced by camphor supplementation, in which greater secondary response to sheep erythrocytes belonged to 750 and 1000 ppm of camphor groups; whereas, diet supplementation with camphor had no significant effect on lymphoid organ weights and heterophil-to-lymphocyte ratio. The greatest AIV antibody titers were seen in groups, which received 1000 and 5000 ppm of camphor (P<0.05) and the values of NDV antibody titers increased with an increase in the camphor consumption. Furthermore, dietary inclusion of 500 ppm of camphor positively decreased coliform populations in the gastrointestinal tract (GIT). In addition, an increase in lactic acid bacteria was also observed in quails, which were fed on the diets containing 750 ppm camphor. Collectively, these data suggest that as a phytogenic feed additive, camphor may effectively act as a modulator of health status (by increasing glucose and HDL), GIT microbiota and immunological responses of the Japanese quail.

Japanese quail (Coturnix coturnix japonica), the smallest farmed avian species, has become a popular meat source among consumers. From the producers’ point of view, commercial quail farming is a profitable avenue and the volume is increasing significantly. Producing value added quail meat is an important way to improve marketing opportunities. The purpose of this paper is to review slaughter, carcass characteristics, meat quality and meat composition of Japanese quail. The status of Japanese quail meat consumption, along with marketing strategies, such as the development of new products and processing methods is discussed, and in addition, the paper covers adding value to spent Japanese quail meat by means of tenderisation with natural agents.

Growth promoters are feed additives used to improve the rate and uniformity of broiler growth whilst increasing feed efficiency. Low, prophylactic doses of antibiotics have been standard practice. The development of direct antibiotic resistance of pathogens in the species receiving the feed, as well as the indirect resistance to similar antibiotics used in human medicine as the result of food chain residues, led to the suspension of the licenses for several major antibiotics in the European Union since 1971, and in 2006 licenses for all sub-therapeutic levels for growth promotion were withdrawn. Therefore, there is great interest in developing natural alternatives to antibiotic growth promoters in order to maintain both bird performance and health. Nigella sativa (black cumin) has been used – in herbal medicine- for centuries for treatment of various disorders including infections. The following review details recent studies on the potential benefits of black cumin in broilers and laying hens performance.

This study was designed to test whether Mucuna pruriens, a natural source of l-dihydroxyphenylalanine (l-DOPA, a dopamine precursor) feeding, can influence development and reproductive conditions in the high food value bird, Japanese quail, Coturnix coturnix japonica. Experiments were performed in both male and female Japanese quail. One-week-old quail chicks were divided into three groups of 36 birds each. Group I was provided with normal diet and served as control. Group II was provided with food mixed with l-DOPA (50 mg/15 g food) and Group III was provided with food mixed with M. pruriens seed powder (480 g/kg food). At the age of 3 weeks (when birds were sexually distinguished) Group I was divided into two sub-groups IA (male) and IB (female) of six birds each. Similarly, Groups II and III were sub-divided into IIA (male), IIB (female) and IIIA (male), IIIB (female), respectively, of six birds each. Observations were made up to the age of 5 weeks. Male experimental groups (IIA and IIIA) showed significantly increased testicular activity, cloacal gland volume, body weight (BW), plasma testosterone and LH level in comparison to control (IA). Similarly female experimental groups (IIB and IIIB) showed significantly greater weight of reproductive organs (uterus, ovary, oviduct and ovarian follicle), BW, egg weight and size and number of follicles. On the other hand, plasma prolactin level was significantly low in comparison to control (IB). Results suggest that M. pruriens is a rich natural source of l-DOPA and the development and reproduction in Japanese quail might be associated with the dopaminergic system of the brain.

During polyspermic fertilisation in birds numerous spermatozoa enter the eggs, in contrast to the situation in mammals where fertilisation is monospermic. However, in birds only one of the spermatozoa which have entered an egg participates in zygote nucleus formation, while the supernumerary spermatozoa degenerate at early embryogenesis. Our previous work has demonstrated the presence in preovulatory quail oocytes of DNase I and II activities able to digest naked λDNA/HindIII substrate in vitro. In the present studies, the activities of both DNases in quail oocytes at different stages of oogenesis and in ovulated mouse oocytes were assayed in vitro using the same substrate. Degradation of quail spermatozoa by quail oocyte extracts was also checked. Digestion of the DNA substrate was evaluated by electrophoresis on agarose gels. The activities of DNase I and II in quail oocytes increased during oogenesis and were the highest in mature oocytes. The activities were present not only in germinal discs but also in a thin layer of cytoplasm adhering to the perivitelline layer surrounding the yolk. At all stages of oogenesis the activity of DNase II was much higher than that of DNase I. DNA contained in spermatozoa was also degraded by the quail oocyte extracts under conditions optimal for both DNases. In contrast to what is observed in quail oocytes, no DNase activities were detected in ovulated mouse eggs; this is logical as they would be useless or even harmful in monospermic fertilisation. The possible role of DNase activities in avian oocytes, in degradation of accessory spermatozoa during polyspermic fertilisation, is discussed.

Heritabilities for egg quality traits in Japanese quail are moderate to high, and there are strong genetic correlations between egg weight and its component parts. Egg quality is affected by selection on body weight, but these effects differ somewhat between experiments, maybe in relation to the origins of breeding lines. Selection on egg production could increase yolk content. Direct selection work on egg quality traits has shown that there was genetic variation for yolk-related characters. The ω6/ω3 PUFA ratio can be improved by selection.

Cloning and sequencing of the cDNA for avian melatonin (MEL) receptors have made it possible to investigate the expression of these receptors in different animal tissues and organs by reverse transcription polymerase chain reaction. Our study demonstrates for the first time, the presence of MEL receptor transcripts in maternal RNA from Japanese quail oocytes and in RNA from the early embryos of the laid eggs. Specific primers permitted discrimination between mel-1a, mel-1b and mel-1c receptor sequences, and special techniques used to obtain the biological material made it possible to avoid accidental contamination with cells of somatic origin. Mel-1c transcript was the main one found in the oocytes and was constantly present in the maternal RNA from individual ovulated oocytes, while mel-1a and mel-1b transcripts were only sporadically present. All three MEL receptor transcripts appeared in the RNA from blastoderms of laid eggs, pointing to their de novo synthesis during uterine embryo development. The relative amount of the MEL receptor transcripts was low in relation to that of β-actin, roughly 3 × 10-4 the amount of control β-actin transcript. The presence of MEL receptor transcripts and their de novo synthesis in the 24-h-old bird embryos point to their probable wider distribution and earlier appearance in development than originally thought; the existence of the corresponding functional receptor proteins in such early embryos has not previously been reported.

Birds exhibit physiological polyspermy, i.e. numerous spermatozoa enter the germinal disc of an oocyte and form pronuclei during fertilisation. However, only one of them unites with the female pronucleus to form a zygote nucleus; the supernumerary spermatozoal nuclei degenerate at the early cleavage stages. To establish a factor responsible for spermatozoal degeneration, the presence of DNase activity was studied in vitro in extracts of Japanese quail oocytes using λ DNA/HindIII as a substrate. The experimental conditions were designed to reveal the presence of either DNase I or DNase II activities, separately. Degradation of the substrate DNA was evaluated by electrophoresis on agarose gels stained with ethidium bromide. High activities of DNase I and DNase II were found in the germinal discs of the largest vitellogenic oocytes. DNase I activity was estimated to be about 3 × 10−3 Kunitz units and DNase II about 4 × 10−2 Kunitz units per germinal disc. DNase I activity in an oocyte seems to increase during oogenesis since DNA degradation by the extracts from the germinal discs of the largest vitellogenic oocytes was much higher than by those from previtellogenic and small vitellogenic oocytes. The presence of high DNase I and II activities in the largest vitellogenic oocytes would point to their role in degradation of DNA from supernumerary spermatozoa entering the ovum during polyspermic fertilisation in birds. The enzymes could be a factor, or one of the factors, in the late block to polyspermy in the cytoplasm of avian eggs. It is suggested here that the DNase activities might also be responsible for poor efficiency in obtaining transgenic birds by microinjection of exogenous DNA into the fertilised chick ovum.

Increasing the energy value of diets with dietary fat, particularly fats rich in saturated fatty acids, can result in the elevation of plasma total and lipoprotein cholesterol. In the present study, experimental diets were designed to examine the effects of increasing the energy content of diets with a saturated fat source and cholesterol in a non-purified diet on hyperlipoproteinaemia and aortic plaque composition in the atherosclerosis-susceptible Japanese quail (Coturnix japonica) model of human atherosclerosis. Commercial poultry diets containing two levels (i.e. 60 or 120 g/kg) of beef tallow as the primary source of saturated fat were balanced for endogenous cholesterol or supplemented with cholesterol (i.e. 0·5 or 5·0 g/kg) and fed to quail for 9 weeks to examine the effects on whole plasma, lipoprotein and aortic plaque lipid composition in relation to aortic plaque formation. Hypercholesterolaemia (P<0·001) was confirmed in birds fed on high-cholesterol (HC) diets only. An interaction (P=0·05) between dietary cholesterol and fat intake level was observed for plasma triacylglycerols (TG) and was specific to changes observed in VLDL composition. Diet-induced changes in lipoprotein total cholesterol, TG and phospholipid composition were greatest in the portomicron and VLDL fractions in birds fed on atherogenic diets. Hyperlipoproteinaemia induced by the 60 g/kg added beef tallow–HC diet resulted in significant (P<0·001) aortic plaque deposition, which was further enhanced in birds fed on the 120 g/kg beef tallow–HC diet. Quail fed on 120 g/kg beef tallow-HC diets exhibited the most severe aortic plaque formation, with marked increases in aortic tissue cholesterol content and quantifiable amounts of several cholesterol oxides (5,6α-epoxy-5α-cholesterol, 7β-hydroxycholesterol, cholestanetriol, 7-ketocholesterol and 25-hydroxycholesterol). In summary, hyperlipoproteinaemia associated with HC diets with a greater proportion of energy from saturated fat produced a combined effect in altering plasma and lipoprotein lipid composition as well as aortic tissue cholesterol and cholesterol oxide content in the Japanese quail.

The Japanese quail has been used as a model of human atherosclerosis to investigate the mechanisms underlying the development of vascular lesions, i.e. hyperlipoproteinaemia and impaired endogenous antioxidant status. In the present study, Japanese quail were fed on semi-purified diets containing butter, beef tallow or soyabean-oil blends, with either 0.5 or 5 g cholesterol/kg for 9 weeks to examine the effects of dietary fat blends varying in fatty acid composition and cholesterol intake on plasma lipids and aortic atherosclerotic plaque and sterol composition. These findings were related to possible diet-induced changes in antioxidant status of selected tissues. Hypercholesterolaemia was confirmed (P < 0.001) in birds fed on high-cholesterol (HC) diets. Plasma total cholesterol concentration and cholesterol content of lipoprotein fractions in hypercholesterolaemic birds were lower (P < 0.05) in quail fed on the soyabean-oil blend. Plasma triacylglycerol content was increased (P < 0.001) in HC-fed birds. Dietary fat blends did not influence plasma triacylglycerol levels. Tissue antioxidant status (catalase (EC 1.11.1.6), glutathione peroxidase (EC 1.11.1.9), glutathione reductase (EC 1.6.4.1) and superoxide dismutase (EC 1.15.1.1) activities and glutathione content) was generally not greatly affected by dietary fat blend or cholesterol treatment. Birds fed on HC diets exhibited severe (P < 0.001) atherosclerotic plaque in aortas which was not influenced by the source of dietary fat blend. Scanning electron microscopy confirmed results of visual aortic plaque scoring using dissecting light microscopy. Several cholesterol oxides were identified and quantified in aortic plaque from HC-fed birds (5,6α-epoxy-5α-cholesterol, 7β-hydroxycholesterol and 7-ketocholesterol) regardless of dietary fat blend. The results indicate that dietary fat blends varying in polyunsaturated: saturated fatty acid ratios only marginally influence the degree of hypercholesterolaemia in atherosclerosis-susceptible quail fed on atherogenic diets only, and are not a factor, compared with sterol feeding, in modulating the degree of atherosclerosis or the aortic oxysterol content in these same birds. Moreover, diet-induced hyperlipoproteinaemia had only a small effect on antioxidant status of selected tissues examined.