Experimental aspergillosis in Japanese quails (Coturnix coturnix japonica)

Intratracheal inoculation of 2-week-old quail chicks with Aspergillus fumigatus resulted in the development of clinical signs within 24 h of infection. These were characterized by anorexia, depression, accelerated respiration and gasping followed by death. The acute course of the disease lasted for 7–10 days followed by recovery in the surviving chicks. The overall mortality during a 6-week observation period was 20%.Although the mean body weight of A. fumigatus infected quail chicks continued to be slightly lower throughout the experiment but the difference, in comparison to controls, was not significant except at 42 days post-infection.There was no appreciable difference in the mean values of Hb, TEC, PCV, MCV, MCH and MCHC between the infected and control chicks at any stage of infection but TLC revealed a leucocytosis from 2–7 days which was the result of increase in the relative percentage of heterophils and decrease in lymphocytes.     

Spatial orientation in Japanese quails (Coturnix coturnix japonica)

Finding a given location can be based on a variety of strategies, for example on the estimation of spatial relations between landmarks, called spatial orientation. In galliform birds, spatial orientation has been demonstrated convincingly in very young domestic chicks. We wanted to know whether adult Japanese quails (Coturnix coturnix japonica) without food deprivation are also able to use spatial orientation. The quails had to learn the relation of a food location with four conspicuous landmarks which were placed in the corners of a square shaped arena. They were trained to find mealworms in three adjacent food cups in a circle of 20 such cups. The rewarded feeders were located during training between the same two landmarks each of which showed a distinct pattern. When the birds had learned the task, all landmarks were displaced clockwise by 90 degrees. When tested in the new situation, all birds redirected their choices with respect to the landmark shift. In subsequent tests, however, the previously correct position was also chosen. According to our results, quails are using conspicuous landmarks as a first choice for orientation. The orientation towards the previously rewarded location, however, indicates that the neuronal representation of space which is used by the birds also includes more fine grain, less conspicuous cues, which are probably also taken into account in uncertain situations. We also presume that the rare orientation towards never rewarded feeders may be due to a foraging strategy instead of being mistakes.     

The paradoxical effects of progesterone on the eggshell quality of laying hens

This study demonstrates the effects of progesterone on eggshell quality and ultrastructure by injecting progesterone into laying hens 2 and 5 h post-oviposition, respectively. Progesterone injected 2 h post-oviposition (P₄-2 h) improved eggshell quality with a significant decrease (P < 0.01) in the thickness of the mammillary layer and a significant increase (P < 0.01) in the thickness of the effective layer in the eggshell ultrastructure compared to the control. Progesterone injected 5 h post-oviposition (P₄-5 h) damaged the eggshell quality by significantly reducing (P < 0.01) the effective layer thickness. Progesterone injected delayed obviously (P < 0.01) the following oviposition. Moreover, the concentrations of Thr, Cys, Leu, Lys, and His in the eggshell membranes were significantly higher (P < 0.05) in the P₄-2 h treated hens whereas Val and Lys were significantly lower (P < 0.05) in P₄-5 h treated hens compared to the control. Therefore, progesterone shows paradoxical effects on eggshell quality depending on the injection time-points post-oviposition, which could explain the contradictions in previous related reports. P₄ injected affected the content of amino acids in eggshell membranes, especially lysine which contributed to eggshell quality. In addition, P₄ injected 2 h after oviposition improved eggshell quality by promoting the premature fusion of mammillary knobs. This work contributed to a novel insight to understanding the mechanism of improving eggshell quality.     

Nocturnal plasma levels of melatonin in quails (Coturnix japonica) injected with l-5-hydroxy-tryptophan.

This study aimed to demonstrate the influence of the systemic administration of l-5-hydroxy-tryptophan (L-HTP) on the plasma levels of melatonin during the dark period in quails. Throughout daylight, the plasma levels of melatonin did not differ significantly, oscillating between 110.2 +/- 15.8 pg.mL(-1) and 157.4 +/- 34.8 pg.mL(-1), from 8 to 16 hours. L-HTP (25 mg.kg(-1), through the intracelomic route) administered at 18 hours lessened significantly the nocturnal increase of the plasma levels of melatonin (controls, 327.3 +/- 20.1 and 315.8 +/- 20.9 pg.mL(-1) vs. 242.1 +/- 24.8 and 217.5 +/- 21 pg.mL(-1), respectively, at 20 and 24 hours, P < 0.05). The results obtained showed that the administration of LHTP reduced the nocturnal melatonin release, possibly by bringing about an increase in serotonin synthesis and synaptic release in the pineal. Therefore, the serotoninergic transmission from the raphe towards the pineal would constitute a mechanism of modulation of the synthesis and melatonin release in quails.     

Growth, developmental stability and immune response in juvenile Japanese quails (Coturnix coturnix japonica).

Stresses are environmental factors which restrict growth or cause a potentially adverse change in an organism. The exposure of developing organisms to environmental stresses may have several physiological consequences including a decrease in immunocompetence. However, mounting an immune response against a foreign antigen may in itself constitute a cost for developing organisms. This cost has potentially long-term consequences for adult function and fitness. This study examines the growth and developmental stability of Japanese quail++ chicks challenged by three non-pathogenic antigens: sheep red blood cells, which assess T-cell-dependent immune responses, and Mycoplasma synoviae and Newcastle disease virus, which assess T-cell-independent responses. Increases in both body mass and wing length were significantly reduced in antigen-challenged birds compared to control birds. Fluctuating asymmetry (FA) in the masses of primary feathers increased from the innermost (1) to the outermost (10) position on the wing. In addition, antigen challenge by M. synoviae and sheep red blood cells was associated with an increase in FA. The cell-mediated response measured by reaction to phytohaemagglutinin was significantly depressed in M. synoviae-challenged birds. White blood cell counts, except for monocytes, were elevated in response to all three antigen treatments. Total plasma protein and haematocrit also differed between treatments but exhibited no clear relationship to antigen challenge. Immune responses clearly impose a stress on developing chicks. Additional research will be required to determine the long-term consequences of developmental stress and assess the selective forces that influence the strength of the immune responses of chicks.     

Transplantation of ovaries in Japanese quail (Coturnix japonica)

This study aimed to extend techniques of ovarian transplantation from chickens to Japanese quail. Ovarian tissue was surgically transplanted from chicks obtained from a line of white-breasted (wb/wb) to those of wild-type (+/+) quail at 1-day of age or at 1 week, with or without subsequent administration of the immunosuppressant, mycophenolate mofetil. Only one out of seven quail (14.3%) transplanted at 1-day of age survived the surgery but 14 of 18 quail (77.8%) transplanted at a week of age survived and grew to sexual maturity. In the 8-week progeny test, among those quail that produced offspring, one of four in the non-immunosuppressed group and all five in the immuosuppressed group produced donor-derived offspring. The proportion of donor-derived to host-derived offspring from five quail in the immnuosuppressed group (173/57) was significantly higher than that from one quail that was not immunosuppressed (3/47). These results suggest that quail ovaries can be transplanted at the age of 1 week and that the immnunosuppressant, mycophenolate mofetil, used for mammalian organ transplantation can suppress immunological rejection in birds. These transplantation techniques could provide an efficient means of recovering a line of quail after cryopreservation.     

The acute phase response in Japanese quail (Coturnix coturnix japonica)

Experiments were conducted to determine the effect of injection of lipopolysaccharide (LPS, from S. typhimurium) or muramyl dipeptide (MDP, N-acetylmuramyl-L-ala-isoglutamine) in Japanese quail. Doses of MDP between 0.3 and 10 mg/kg body wt. had no effect on body temperature. In contrast, doses of 1.0-22.5 mg LPS/kg body wt. caused significant increases in body temperature. None of the doses of LPS or MDP resulted in mortality. The febrile response to LPS was diminished following a second injection 48 h after the first, and was absent following a third injection. Plasma zinc, an indicator of the acute phase response, was significantly reduced by either LPS or MDP after the first injection (P<0.001), but not after the second or third injection. Splenic interleukin 1-beta (IL-1beta) mRNA expression was increased after the first and last injection of LPS (P<0.001), but only after the first injection of MDP (P<0.005). Hepatic IL-1beta mRNA expression was increased after the first, but not the third injection of LPS (P<0.001), while MDP had no effect. These data indicate that Japanese quail are less sensitive to MDP than LPS, and that quail demonstrate tolerance to LPS following repeated injections.     

Effect of alliums on total lipid in plasma and tissues of Japanese quails (Coturnix coturnix japonica) with respect to age and sex

Dietary onion and garlic caused an increase in the level of liver and plasma total lipids in Coturnix coturnix japonica. This increase could be due to the effect of an increased feed intake, bile production, digestion and absorption that in turn caused an increased utilisation of dietary fat, increased transfer of dietary lipids to the liver and/or due to increased lipogenesis as such. However, there was no increase in the muscle lipid content. This effect in the muscle could be due to inhibitory effect of onion or garlic on lipoprotein lipase activity. Further, the changes in the tissue total lipid level in the control group due to change in age and sex were also observed.     

Peripheral blood in the Japanese quail (Coturnix coturnix japonica) in acute poisoning by different insecticides

The purpose of this study was to examine the effect of chlorphenvinphos and foschlor on the erythrocytes and leucocytes in the Japanese quail (Coturnix coturnix japonica). It was found that there is no decided change in the number of erythrocytes after ingesting chlorphenvinphos, whereas foschlor significantly reduces RBC content. The effect of the two pesticides is shown by an increase in reticulocytes and erythroblasts. Chlorphenvinphos significantly reduces, but foschlor increases, thrombocyte content. Changes in the leucocyte system were seen after poisoning with both chlorphenvinphos and foschlor, in the form of distinct neutrophilic leucocytosis and eosinopaenia. A marked increase in the number of basophils was found after ingesting chlorphenvinphos, and a distinct increase in monocytes after ingesting both pesticides.     

The postnatal demasculinization of sexual behavior in the Japanese quail (Coturnix coturnix japonica)

Three experiments were performed to analyze the time course of demasculinization in the Japanese quail and to test the activating and organizing effects of estradiol (E2) in adult sexually active birds. In Experiment 1, males and females were castrated at the age of 1 day or 1, 2, 4, and 6 weeks and treated as adults with testosterone (T). The age of castration had no effect on behavior and morphology in males. Plasma gonadotrophins (LH and FSH) were, however, higher in males castrated at or before than in those castrated after 2 weeks of age. This suggests that postnatal testicular secretions have organizing effects on the pituitary activity. Females which were castrated before 1 week of age were less sensitive to the activating effects of T than males, but were not fully demasculinized. The demasculinization of different reproductive characteristics such as male sexual behavior, cloacal gland size, and weight of the syringeal muscles is achieved in females at different times posthatching. In Experiment 2, castration of male and female quail at the ages of 4 days or 4 weeks confirmed that postnatal ovarian secretions contribute to the full behavioral and morphological demasculinization of females. It is easier to elicit mounting in T-treated females when they are tested in their home cage instead of a test arena. This difference was not observed in males. During Experiment 3, it was impossible to demasculinize sexually active adult males or females by treatment with Silastic implants of E2. E2 did not maintain sexual behavior in ovariectomized females showing male sexual behavior when treated with T but maintained the behavior in males.     

The post-natal differentiation of sexual behaviour in the Japanese quail (Coturnix coturnix japonica)

An experiment was carried out to study the contribution of endogenous steroids during postnatal life to the sexual differentiation in Japanese quail. Male and female quail were gonadectomized at one week of age and when adult received testosterone silastic capsules. Seventy seven percent of these females showed male-type sexual behaviour and 46 percent even copulated. All males showed sexual behaviour including cloacal contact movements. Males and females grew cloacal glands of nearly identical sizes in response to the testosterone treatment. It is concluded that sexual differentiation in quail is at least in part a postnatal process and more research is needed to elucidate its exact mechanisms and time course.     

Mating Call Discrimination in Female European (Coturnix c. coturnix) and Japanese Quail (Coturnix c. japonica)

Each year, thousands of domestic Japanese and hybrid quails are released within the breeding range of the European quail. We showed recently that no post‐zygotic isolating mechanisms have yet been established between these subspecies. The aim of this study was to investigate whether pre‐zygotic mechanisms are strong enough to prevent hybridization. We tested the level of subspecies selectivity in females of European and Japanese quail respectively using playbacks of European, hybrid and Japanese male mating calls. European quail females emitted the greatest number of rally calls in response to mating calls by conspecific males. Their responses were the weakest to mating calls produced by males of the other subspecies and intermediate to mating calls by hybrid males. In contrast, Japanese quails produced similar responses to all types of mating calls. These results suggest that mixed pairs could form in the wild. The European quail could thus become one of the most endangered galliforms of the Western Palearctic.     

Effects of starvation on gonadotropin and thyrotropin subunit mRNA levels and plasma hormone levels in the male Japanese quail (Coturnix coturnix japonica)

Contents of mRNAs encoding LHbeta-, FSHbeta-, TSHbeta- and common a-subunit precursor molecules were measured in male Japanese quail deprived of food for three days. Plasma LH, FSH, thyroxine and triiodothyronine levels were also measured in the same birds. Plasma LH levels declined during the period of food deprivation. Levels in starved birds were not different from those in control birds after one day of starvation but were significantly lower after three days. Plasma FSH levels showed a similar decline, although the changes were not significant. Plasma thyroxine levels did not decrease during starvation, whilst plasma triiodothyronine levels decreased drastically and significantly soon after the start of starvation. All the hormone subunit mRNA contents in starved birds also decreased, with differences from control birds significant 3 days after the start of starvation. Plasma FSH levels showed a strong positive correlation with pituitary FSHbeta mRNA levels, while plasma LH levels had a strong positive correlation with common a mRNA levels and practically no correlation or even a negative correlation with LHbeta mRNA levels. These results suggest that starvation suppresses not only gonadotropin and thyrotropin secretion but also their synthesis in the pituitary gland. Furthermore, these results showed that FSH and LH have different synthesis and secretion dynamics in the Japanese quail. Contradicting results with TSHbeta mRNA and thyroid hormones lead us to assume that starvation affects thyroid hormone metabolism in peripheral tissue, presumably in the liver.     

The effect of DMA level on morphology and fertilising ability of Japanese quail (Coturnix japonica) spermatozoa

The effect of different levels (2, 4 or 6%) of DMA (dimethylacetamide) on the morphology and fertilising ability of unfrozen quail spermatozoa was evaluated. Semen was collected from 72 males kept individually in cages and randomly divided into four groups: Group I--control -- fresh undiluted semen (12 males) and three experimental groups (20 males each) - semen diluted 1:1 with Lake's extender and supplemented with 2% (Group II), 4% (Group III) or 6% (Group IV) of DMA (final concentration). Sperm morphology was evaluated at each step of semen preparation, i.e. in fresh and diluted semen, semen supplemented with DMA and semen that remained after insemination. For fertility tests, 36 females were divided into four groups (nine females each). Females in the control group were inseminated with 10 microl of fresh semen, in the experimental groups with 40 microl of diluted semen. Each stage of quail semen treatment had a deleterious effect on sperm morphology. The highest percentage of morphologically normal cells in semen evaluated after insemination, was observed in samples with 2% DMA, and the lowest--in samples with 6% DMA. Semen dilution and DMA addition significantly affected the fertilising potency of spermatozoa. Fertility of eggs collected from the control group (71.5% on average) was significantly higher (P相似文献   

Dynamics of crowing development in the domestic Japanese quail (Coturnix coturnix japonica)

Species-specific behaviours gradually emerge, via incomplete patterns, to the final complete adult form. A classical example is birdsong, a learned behaviour ideally suited for studying the neural and molecular substrates of vocal learning. Young songbirds gradually transform primitive unstructured vocalizations (subsong, akin to human babbling) into complex, stereotyped sequences of syllables that constitute adult song. In comparison with birdsong, territorial and mating calls of vocal non-learner species are thought to exhibit little change during development. We revisited this issue using the crowing behaviour of domestic Japanese quail (Coturnix coturnix japonica). Crowing activity was continuously recorded in young males maintained in social isolation from the age of three weeks to four months. We observed developmental changes in crow structure, both the temporal and the spectral levels. Speed and trajectories of these developmental changes exhibited an unexpected high inter-individual variability. Mechanisms used by quails to transform sounds during ontogeny resemble those described in oscines during the sensorimotor phase of song learning. Studies on vocal non-learners could shed light on the specificity and evolution of vocal learning.     

Evidence for introgressive hybridization of wild common quail (Coturnix coturnix) by domesticated Japanese quail (Coturnix japonica) in France

Many cases of introgressive hybridization have been reported among birds, particularly following introduction to the natural environment of individuals belonging to non-native similar taxa. This appears to be the case for common quail (Coturnix coturnix) in France where wild populations artificially come into contact with domesticated Japanese quail (Coturnix japonica) raised for meat and egg production but sometimes released for hunting purposes. In order to highlight the possible existence of gene flows between both taxa, a comparison of nuclear (25 microsatellite loci) and mitochondrial (sequencing and RFLP) DNA polymorphisms was performed on 375 common quails (from France, Spain and Morocco) and 140 Japanese quails (from France and Japan). Genetic diversity was assessed, and analyses (Factorial Correspondence Analysis, Bayesian admixture) of molecular polymorphisms revealed clear differentiation between the two taxa, making it possible to detect for hybrids among quails sampled in the wild. Eight birds expected to be common quail were found to be two pure Japanese quail, one probable backcross to C. japonica, three F1/F2 hybrids, and two probable backcrosses to Coturnix coturnix. These results show that Japanese quails were released and suggest that the two taxa hybridize in the wild. They confirm the urgent need for preventing the release of pure Japanese or hybrid quails to preserve the genetic integrity of C. coturnix. The tools developed for this study should be useful for accurate monitoring of wild quail populations within the framework of avifauna management programs.