Showing papers on "Coturnix published in 2006"

Experimental evidence that corticosterone affects offspring sex ratios in quail

Abstract: Recent studies have shown that some species of birds have a remarkable degree of control over the sex ratio of offspring they produce. However, the mechanism by which they achieve this feat is unknown. Hormones circulating in the breeding female are particularly sensitive to environmental perturbations, and so could provide a mechanism for her to bias the sex ratio of her offspring in favour of the sex that would derive greatest benefit from the prevailing environmental conditions. Here, we present details of an experiment in which we manipulated levels of testosterone, 17beta-oestradiol and corticosterone in breeding female Japanese quail (Coturnix coturnix japonica) using Silastic implants and looked for effects on the sex ratio of offspring produced. Offspring sex ratio in this species was significantly correlated with faecal concentrations of the principal avian stress hormone, corticosterone, and artificially elevated levels of corticosterone resulted in significantly female-biased sex ratios at laying. Varying testosterone and 17beta-oestradiol had no effect on sex ratio alone, and faecal levels of these hormones did not vary in response to corticosterone. Our results suggest that corticosterone may be part of the sex-biasing process in birds.

Integrated maps in quail (Coturnix japonica) confirm the high degree of synteny conservation with chicken (Gallus gallus) despite 35 million years of divergence

Abstract: By comparing the quail genome with that of chicken, chromosome rearrangements that have occurred in these two galliform species over 35 million years of evolution can be detected. From a more practical point of view, the definition of conserved syntenies helps to predict the position of genes in quail, based on information taken from the chicken sequence, thus enhancing the utility of this species in biological studies through a better knowledge of its genome structure. A microsatellite and an Amplified Fragment Length Polymorphism (AFLP) genetic map were previously published for quail, as well as comparative cytogenetic data with chicken for macrochromosomes. Quail genomics will benefit from the extension and the integration of these maps. The integrated linkage map presented here is based on segregation analysis of both anonymous markers and functional gene loci in 1,050 quail from three independent F2 populations. Ninety-two loci are resolved into 14 autosomal linkage groups and a Z chromosome-specific linkage group, aligned with the quail AFLP map. The size of linkage groups ranges from 7.8 cM to 274.8 cM. The total map distance covers 904.3 cM with an average spacing of 9.7 cM between loci. The coverage is not complete, as macrochromosome CJA08, the gonosome CJAW and 23 microchromosomes have no marker assigned yet. Significant sequence identities of quail markers with chicken enabled the alignment of the quail linkage groups on the chicken genome sequence assembly. This, together with interspecific Fluorescence In Situ Hybridization (FISH), revealed very high similarities in marker order between the two species for the eight macrochromosomes and the 14 microchromosomes studied. Integrating the two microsatellite and the AFLP quail genetic maps greatly enhances the quality of the resulting information and will thus facilitate the identification of Quantitative Trait Loci (QTL). The alignment with the chicken chromosomes confirms the high conservation of gene order that was expected between the two species for macrochromosomes. By extending the comparative study to the microchromosomes, we suggest that a wealth of information can be mined in chicken, to be used for genome analyses in quail.

Impairment of testicular function in adult male Japanese quail (Coturnix japonica) after a single administration of 3-methyl-4-nitrophenol in diesel exhaust particles.

Abstract: The effects of 3-methyl-4-nitrophenol (PNMC), a component of diesel exhaust, on reproductive function were investigated in adult male Japanese quail. The quail were treated with a single i.m. dose of PNMC (78, 103 or 135 mg/kg body weight), and trunk blood and testes were collected 1, 2 or 4 weeks later. Various levels of testicular atrophy were observed in all groups treated with PNMC. Sperm formation, cloacal gland area, and plasma LH and testosterone concentrations were also reduced in birds with testicular atrophy. To determine the acute effect of PNMC on gonadotrophin from the pituitary, adult male quail were administrated a single i.m. injection of PNMC (25 mg/kg), and plasma concentrations of LH were measured at 1, 3 and 6 h. This dose significantly lowered plasma levels of LH at all three time points. These results suggest that PNMC acts on the hypothalamus-pituitary axis, by reducing circulating LH within a few hours of administration and subsequently reducing testosterone secretion. In addition, in order to investigate the direct effects of PNMC on the secretion of testosterone from testicular cells in quail testes, cultured interstitial cells containing Leydig cells were exposed to PNMC (10(-6), 10(-5) or 10(-4) M) for 4, 8 or 24 h. These quantities of PNMC significantly reduced the secretion of testosterone in a time- and dose-dependent manner. The present findings also suggest a direct effect of PNMC on the testis to reduce testosterone secretion. This study clearly indicates that PNMC induces reproductive toxicity at both the central and testicular levels, and disrupts testicular function in adult male quail.

Isolation of avian influenza virus A subtype H5N1 from internal contents (albumen and allantoic fluid) of Japanese quail (Coturnix coturnix japonica) eggs and oviduct during a natural outbreak.

Abstract: Avian influenza virus (AIV) was recovered from the internal contents of eggs, including mixture of albumen and allantoic fluid, and from the oviduct of naturally infected Japanese quail (Coturnix coturnix japonica) flocks in the southern part of Thailand. The virus titers of 10(4.6)-10(6.2) ELD(50)/mL were directly measured from the internal content of infected eggs. The virus was isolated by chorioallantoic sac inoculation of embryonating chicken eggs. Infected allantoic fluid was identified as hemagglutinating virus and then was indicated the presence of H5 hemagglutinin. The virus was confirmed to be H5N1 subtype influenza A virus by reverse transcriptase-polymerase chain reaction. Additionally, real-time reverse transcriptase-polymerase chain reaction assay could specifically detect influenza virus subtype H5. Furthermore, indirect fluorescent antibody (IFA) test by using specific anti-influenza A monoclonal antibody indicated that virus antigens were detected in the parenchyma of multiple tissues. Systemic localization of viral antigen detected was certainly considered to be viremic stage. In addition, influenza virus antigen was also detected by IFA in allantoic fluid sediments isolated from internal content of egg or oviduct. The conclusion of isolated AIV type A subtype H5N1 from these two infected materials was correlated to the viremic stage of infection because the virus antigens could be observed in almost all tissues. Conclusively, the need for adequate safeguards to prevent contamination and spread of the virus to the environment during movement of eggs--including hatching eggs, cracked eggs, and other relevant infected materials-- or egg consumption from area of outbreak is emphasized and must not be ignored for the reasons of animal, public, and environmental health.

Chronic administration of leptin in Asian Blue Quail.

Abstract: It is well known that leptin has the capacity to reduce food intake, cause body weight loss, and increase energy expenditure in several vertebrate species. In this study, we investigated the effects of chronically elevated leptin levels on behavior and physiology of Asian Blue Quail (Coturnix chinensis). Fifteen male quail were treated with chicken leptin dissolved in phosphate-buffered saline (PBS) via subcutaneously inserted osmotic pumps that released approximately 1 microg/g body weight/day during a 14-day period. Another 15 males acted as controls and their pumps released PBS only. All males were housed together with two females. We observed a decrease in body weight and feeding behavior in leptin-treated birds, but not in control birds, after 2 days of treatment. Thereafter, all birds increased in weight. Males treated with leptin were more active and more likely to preen the day after the beginning of the treatment. Plasma cholesterol levels in leptin birds decreased during the first week of treatment and plasma triglycerides tended to remain lower compared to the controls during the whole 2-week period of treatment. Glucose levels appeared stable during the observation period. Leptin-treated males remained closer to accompanying females than did control males, and females together with leptin males took longer to lay their first egg compared to females together with control males. This is the first article showing the effect of leptin on cholesterol and triglyceride levels in birds. We also observed a change in the activity and male-female interaction pattern in tested quail.

Comparison of Egg Weight Between Two Quail Strains

Abstract: 3 Abstract: In order to investigate egg weight of two quail strains 2550 eggs of Japanese quail (Coturnix japanese) and 1975 eggs of Range quail (Coturnix ypisilophorus) were weighted individually at three age groups (first group: 60-145, second group: 145-230, and last group: 300-385 days of age). Body weights of two strains were not significantly different (p>0.05). Body weights at 60 days age were significantly different (p 0.05). Egg weight of Japanese quails and Range quails were 11.23±0.03 and 11.17±0.05 respectively which were not significantly different (p>0.05). Effects of the interaction of strain, age and sex for egg weight and body weight were significantly different (p<0.01). Minimum and maximum egg weight for Japanese quail were 7.08 and 13.84gr respectively, however these records were 7.01 and 13.84gr for Range quail. Individual variation of in two strains for eggs weight were significantly different (p<0.01).

Sexual fetishism in a quail (Coturnix japonica) model system: test of reproductive success.

Abstract: In the present study, the authors explored the reproductive consequences of fetishistic behavior in a previously developed animal model of sexual fetishism (F Koksal et al, 2004) Male domesticated quail (Coturnix japonica) received sexual conditioning trials in which a terrycloth object (the conditioned stimulus [CS]) was paired with the opportunity to copulate with a female quail (the unconditioned stimulus) Approximately half of the male quail came to copulate with the CS object and were considered to have developed fetishistic behavior Each of the male quail was then tested with a female quail, whose eggs were incubated to determine rates of fertilization The CS object was present for 30 s before and during the copulation test Fetishistic male quail were slower to achieve cloacal contact with the female quail and showed less efficient copulatory behavior However, they fertilized a greater proportion of eggs than nonfetishistic male quail These results are unexpected from previous studies of the relationship between reproductive success and copulatory behavior and are discussed in terms of how fetishistic behavior directed toward an inanimate object may modify male-female interactions

Molecular mechanism of photoperiodic time measurement in the brain of Japanese quail.

Abstract: In most organisms living in temperate zones, reproduction is under photoperiodic control. Although photoperiodic time measurement has been studied in organisms ranging from plants to vertebrates, the underlying molecular mechanism is not well understood. The Japanese quail (Coturnix japonica) represents an excellent model to study this problem because of the rapid and dramatic photoperiodic response of its hypothalamic-pituitary-gonadal axis. Recent investigations of Japanese quail show that long-day-induced type 2 deiodinase (Dio2) expression in the mediobasal hypothalamus (MBH) plays an important role in the photoperiodic gonadal regulation by catalyzing the conversion of the prohormone thyroxine (T(4)) to bioactive 3,5,3'-triiodothyronine (T3). The T3 content in the MBH is approximately 10-fold higher under long than short days and conditions, and the intracerebroventricular infusion of T3 under short days and conditions mimics the photoperiodic gonadal response. While Dio2 generates active T3 from T4 by outer ring deiodination, type 3 deiodinase (Dio3) catalyzes the conversion of both T3 and T4 into inactive forms by inner ring deiodination. In contrast to Dio2 expression, Dio3 expression in the MBH is suppressed under the long-day condition. Photoperiodic changes in the expression of both genes during the photoinduction process occur before the changes in the level of luteinizing hormone (LH) secretion, suggesting that the reciprocal changes in Dio2 and Dio3 expression act as gene switches of the photoperiodic molecular cascade to trigger induction of LH secretion.

Mapping of panda plumage color locus on the microsatellite linkage map of the Japanese quail

Abstract: Panda (s) is an autosomal recessive mutation, which displays overall white plumage color with spots of wild-type plumage in the Japanese quail (Coturnix japonica). In a previous study, the s locus was included in the same linkage group as serum albumin (Alb) and vitamin-D binding protein (GC) which are mapped on chicken (Gallus gallus) chromosome 4 (GGA4). In this study, we mapped the s locus on the microsatellite linkage map of the Japanese quail by linkage analysis. Segregation data on the s locus were obtained from three-generation families (n = 106). Two microsatellite markers derived from the Japanese quail chromosome 4 (CJA04) and three microsatellite markers derived from GGA4 were genotyped in the three-generation families. We mapped the s locus between GUJ0026 and ABR0544 on CJA04. By comparative mapping with chicken, this locus was mapped between 10.0 Mb and 14.5 Mb region on GGA4. In this region, the endothelin receptor B subtype 2 gene (EDNRB2), an avian-specific paralog of the mammalian endothelin receptor B gene (EDNRB), is located. Because EDNRB is responsible for aganglionic megacolon and spot coat color in mouse, rat and equine, EDNRB2 is suggested to be a candidate gene for the s locus. The s locus and the five microsatellite markers were mapped on CJA04 of the Japanese quail. EDNRB2 was suggested to be a candidate gene for the s locus.

In ovo exposure quail assay for risk assessment of endocrine disrupting chemicals

Abstract: Although there are in vivo assays using various organisms for the risk assessment of chemicals with endocrine disrupting properties, effective experimental methods for avian species are still under debate. We have developed an in ovo exposure assay using Japanese quail eggs, aimed at assessing disrupting effects on avian reproductive development and function. Hybrid eggs from Brazilian Brown male and White Egg female quails, which can be genetically sexed by their plumage color after hatching, were prepared, and test materials dissolved in olive oil were injected into the air-chamber on day 10 of incubation. After sexual maturation of hatched chicks, we observed egg production by females and the egg quality and male-typical reproductive behavior, and then examined reproductive system morphology and serum steroid concentrations in both sexes. Treatment with a synthetic estrogen, diethylstilbestrol (DES, 0.5-50 ng/g egg), dose-dependently reduced the eggshell thickness and strength of eggs. A few females treated with 5 ng/g DES per egg produced soft-shelled/ unmarked eggs, and all laying females treated with 50 ng/g egg produced eggs completely lacking shells. DES also induced shortening of the left oviduct and abnormal development of the right oviduct in a dose-dependent manner, while testis weight was reduced symmetrically. In addition, 2,2',4',6'-tetrachlorobiphenyl-4-ol (10-1,000 ng/g egg), which previously showed relatively high estrogenic activity in vitro, caused dose-dependent shortening of the left oviduct and reduction in testis weight. The methods for evaluating endocrine disrupting effects and preparing experimental birds proposed in the present study are expected to facilitate assays for avian reproductive toxicology.

Expression of qBrn-1, a new member of the POU gene family, in the early developing nervous system and embryonic kidney.

Abstract: It has been shown that POU domain genes play critical roles in the development of the nervous system. We have obtained a new member of the class III POU domain genes, qBrn-1, from the cDNA library of embryonic day 5 quail and have made an extensive expression pattern analysis of qBrn-1 and qBrn-2 throughout the early embryonic development by in situ hybridization. With a specific antibody we prepared, further analysis by immunohistochemistry showed that the location of qBrn-1 protein was consistent with that of the transcripts in the early developing quail. Our results showed that both qBrn-1 and qBrn-2 were preferentially expressed in the developing central nervous system, and their transcripts were initially detected in the neural plate and later in the distinct regions of the neural tube with a stage-dependent pattern. Moreover, their expression was also detected in both notochord and neural crests. However, qBrn-1 signal, different from qBrn-2, was more widely found in the auditory pits, branchial arches, and in the mesodermal components of the developing kidney. And the expression of qBrn-1 in nephric region was earlier and wider than that of mouse Brn-1, suggesting the characteristic function of qBrn-1 in the kidney formation. The distinct dynamic expression patterns of qBrn-1 and qBrn-2 indicate multiple roles of the class III POU genes in quail neurogenesis and organogenesis.

A novel family of repetitive DNA sequences amplified site-specifically on the W chromosomes in Neognathous birds.

Abstract: A novel family of repetitive DNA sequences was molecularly cloned from ApaI-digested genomic DNA of two Galliformes species, Japanese quail (Coturnix japonica) and guinea fowl (Numida meleagris), and characterized by chromosome in-situ hybridization and filter hybridization. Both the repeated sequence elements produced intensely painted signals on the W chromosomes, whereas they weakly hybridized to whole chromosomal regions as interspersed-type repetitive sequences. The repeated elements of the two species had high similarity of nucleotide sequences, and cross-hybridized to chromosomes of two other Galliformes species, chicken (Gallus gallus) and blue-breasted quail (Coturnix chinensis). The nucleotide sequences were conserved in three other orders of Neognathous birds, the Strigiformes, Gruiformes and Falconiformes, but not in Palaeognathous birds, the Struthioniformes and Tinamiformes, indicating that the repeated sequence elements were amplified on the W chromosomes in the lineage of Neognathous birds after the common ancestor diverged into the Palaeognathae and Neognathae. They are components of the W heterochromatin in Neognathous birds, and a good molecular cytogenetic marker for estimating the phylogenetic relationships and for clarifying the origin of the sex chromosome heterochromatin and the process of sex chromosome differentiation in birds.

Effects of diethylstilbestrol and ethinylestradiol on gene transcription of very low-density apolipoprotein II in the liver of Japanese quail, Coturnix japonica.

Abstract: Very low-density apolipoprotein II (apoVLDL) is one of the constituents of yolk in avian eggs. The expression of the apoVLDL gene is highly specific to the liver in mature female birds during the egg-laying period but is stimulated by exogenous estrogens in immature male birds. In the present study, we compared the effects of two estrogenic compounds, diethylstilbestrol and ethinylestradiol, on the expression of apoVLDL mRNA in the liver of Japanese quail (Coturnix japonica). Three-week-old, immature male quail were treated with a single intraperitoneal injection of the estrogenic compounds, and the level of apoVLDL mRNA in the liver was measured by gene-specific real-time polymerase chain reaction. Diethylstilbestrol and ethinylestradiol had a similar effect on the level of mRNA, increasing it in a dose-dependent manner. Next, the levels of apoVLDL mRNA in the liver of male embryos, which were developed in fertile eggs laid by quail injected with the estrogenic compounds during yolk formation, were measured. Maternal exposure to ethinylestradiol caused an increase in the mRNA in embryos, whereas exposure to diethylstilbestrol had no effect. These results point out the importance of the route of administration to the evaluation of the estrogenic effects of endocrine disruptors in oviparous species.

Quail poisoning in a child.

Abstract: Context It has been well known since ancient times that the consumption of quail may be deleterious to health. The European quail sub-species (Coturnix coturnix coturnix), common to Europe, North Africa, and western Asia is indeed potentially poisonous to humans, but only during the autumn migration (not during their return flight in spring). Quail poisoning is an acute dietary-toxicological syndrome. Issue In this case report, we describe a rare, non-fatal case of quail poisoning in a 12-year-old boy. The victim was admitted to hospital 5 hours after the consumption of quail because of the signs and symptoms, as well as laboratory findings (elevation of serum muscle enzymes, myoglobinuria) significant of acute rhabdomyolysis. He was treated symptomatically with bed rest, forced continuous diuresis, urine alkalization, and maintenance of fluid and electrolyte balance. The victim recovered completely without sequelae after 8 days hospitalization. Lessons The aetiology of this syndrome is still unclear. It has been suggested that a toxic effect or a genetic sensitivity plays a major role. Many cases of quail poisoning in adults have been reported previously on the island of Lesbos during autumn. To our knowledge, this is the first case reported in a child.

Effects of enclosure size on sexual behavior of Japanese quail (Coturnix japonica)

Abstract: The authors determined whether results of experiments on copulatory and affiliative behavior of pairs of Japanese quail (Coturnix japonica) conducted in a closely confining apparatus would predict behavior in a large enclosure in which female quail could avoid contact with male quail. As found previously in studies of closely confined quail, in a large enclosure containing numerous barriers, both unmated female quail and mated female quail laying unfertilized eggs were more likely to remain near a confined male quail than were mated female quail laying fertilized eggs. Furthermore, the number of copulations that a pair engaged in when closely confined predicted the number of copulations that they engaged in when they were in the large enclosure. Patterns of affiliation and of mating in a confining laboratory apparatus thus predicted behavior in a larger enclosure that provided female quail with opportunity to avoid contact with male quail.

Detection of Genetic Diversity of Four Quail Populations in East China Based on Three Microsatellite Markers

Abstract: Three microsatellite loci were used with four quail (Coturnix spp.) populations at their DNA level, in East China for the detection of genetic diversity of the no genetic relationship resources. Based on the microsatellites and data generated from the experiment, allele per locus detected ranged from four to five and proportion of polymorphism observed was in the neighbourhood of 100%. To detect the level of genetic diversity existing in quail populations in this region, we estimated gene diversity for each locus (h) and among loci (H). The results demonstrated that (H) ranged from 0.4627±0.03 to 0.6345±0.05 and the average gene diversity (H) observed in the populations were in the increasing order of 0.4627, 0.5146, 0.5549 and 0.6345, respectively. The range of mean of the effective allele number (Ne) was 1.8688±0.12 to 2.7981±0.43, mean polymorphism information content (PIC) was within 0.3767 to 0.5713 and cumulative power of discrimination across all populations gave 95.76%. The phylogenetic analyses of all data generated revealed that a high level of genetic diversity exists between the available quail populations in East China and that microsatellite markers are adequately suitable for examining genetic diversity of quail populations.

Chronic Administration of Leptin in Asian

Abstract: It is well known that leptin has the capacity to reduce food intake, cause body weight loss, and increase energy expenditure in several vertebrate species. In this study, we investigated the effects of chronically elevated leptin levels on behavior and physiology of Asian Blue Quail (Coturnix chinensis). Fifteen male quail were treated with chicken leptin dissolved in phosphate-buffered saline (PBS) via subcutaneously inserted osmotic pumps that released approximately 1mg/g body weight/day during a 14-day period. Another 15 males acted as controls and their pumps released PBS only. All males were housed together with two females. We observed a decrease in body weight and feeding behavior in leptin-treated birds, but not in control birds, after 2 days of treatment. Thereafter, all birds increased in weight. Males treated with leptin were more active and more likely to preen the day after the beginning of the treatment. Plasma cholesterol levels in leptin birds decreased during the first week of treatment and plasma triglycerides tended to remain lower compared to the controls during the whole 2-week period of treatment. Glucose levels appeared stable during the observation period. Leptin-treated males remained closer to accompanying females than did control males, and females together with leptin males took longer to lay their first egg compared to females together with control males. This is the first article showing the effect of leptin on cholesterol and triglyceride levels in birds. We also observed a change in the activity and male-female interaction pattern in tested quail. J. Exp. Zool. 305A:13-22, 2006. r 2005 Wiley-Liss, Inc.

Seasonal changes in plasma calcium and inorganic phosphate levels in relation to parathyroid structure of the grey quail, Coturnix coturnix coturnix Linnaeus.

Abstract: Plasma Ca concentration (annual mean) in males Coturnix cotumix coturnix was 10.27 +/- 0.14 mg/100 ml while it was slightly higher (11.85 +/- 0.15 mg/100 ml) among females. Plasma Pi levels (annual mean) in males and females were 5.62 +/- 0.12 mg/100 ml and 6.52 +/- 0.20 mg/100 ml, respectively. While the males did not exhibit marked fluctuation in plasma Ca and Pi levels either in winter or summer, the females did record significant elevation in the levels of both these electrolytes during breeding season. The peak values of plasma Ca (17.66 +/- 0.38 mg/100 ml) and Pi (8.64 +/- 0.22 mg/100 ml) in females were observed during June. Parathyroid gland of the grey quail exhibited hyperactivity (hypertrophy and hyperplasia) during breeding season, however, the activity was more conspicuous among females than in males. The maximum increase in cell and nuclear diameters were observed in females during May-July. The follicles were also filled with AF- and PAS-positive materials during these months. The glands depicted signs of hypoactivity and degeneration during peak winter season (November-December) as evident by decrease in cell and nuclear diameters as well as vacuolation in the chief cells.

In vitro degradation of hexanitrohexaazaisowurtzitane (CL-20) by cytosolic enzymes of Japanese quail and the rabbit.

Abstract: Hexanitrohexaazaisowurtzitane (CL-20) is a polycyclic nitramine explosive and propellant, currently being considered as a potential replacement for existing cyclic nitramine explosives. Earlier studies have provided evidence suggestive of adverse liver effects in adult Coturnix spp. exposed to CL-20, yet analysis of tissue samples (plasma, liver, brain, heart, or spleen) indicated that CL-20 was not detectable in these treated animals. The present study was conducted to identify and purify the enzymes capable of CL-20 biotransformation. Results indicate that the hepatic biotransformation of CL-20 in vitro was inhibited by ethacrynic acid (93%) and by the glutathione (GSH) analogue S-octylglutathione (80%), suggesting the involvement of glutathione-S-transferase (GST). Partially purified cytosolic α- and μ-type GST (requiring presence of GSH as a cofactor) from quail and rabbit liver was capable of CL-20 biotransformation. The degradation of CL-20 (0.30 ± 0.05 and 0.40 ± 0.02 nmol/min/mg protein for quail and rabbit, respectively) was accompanied with the formation of nitrite and consumption of GSH. Using liquid chromatography/mass spectrometry, we detected two intermediates, that is, open-ring, monodenitrated GSH–conjugated CL-20 biotransformation product with the same deprotonated molecular mass ion at 699 Da, suggesting isomeric forms of the intermediate metabolites. Identity of the conjugated metabolites was confirmed by using ring-labeled [15N]CL-20 and the nitro group–labeled [15NO2]CL-20. These data suggest that the in vitro biotransformation of CL-20 by GST under the conditions tested may be a key initial step in the in vivo degradation of CL-20 in the quail and resulted in the formation of more biologically reactive intermediates than the parent compound. These data will aid in our understanding of the biotransformation processes of CL-20 in vivo.