Showing papers on "Coturnix published in 2019"

Toxicokinetics of Imidacloprid-Coated Wheat Seeds in Japanese Quail ( Coturnix japonica) and an Evaluation of Hazard

Abstract: Birds are potentially exposed to neonicotinoid insecticides by ingestion of coated seeds during crop planting. Adult male Japanese quail were orally dosed with wheat seeds coated with an imidacloprid (IMI) formulation at either 0.9 or 2.7 mg/kg body weight (BW) (∼3 and 9% of IMI LD50 for Japanese quail, respectively) for 1 or 10 days. Quail were euthanized between 1 and 24 h postexposure to assess toxicokinetics. Analysis revealed rapid absorption (1 h) into blood and distribution to the brain, muscle, kidney, and liver. Clearance to below detection limits occurred at both dose levels and exposure durations in all tissues within 24 h. Metabolism was extensive, with 5-OH-IMI and IMI-olefin detected at greater concentrations than IMI in tissues and fecal samples. There was no lethality or overt signs of toxicity at either dose level. Furthermore, no evidence of enhanced expression of mRNA genes associated with hepatic xenobiotic metabolism, oxidative DNA damage, or alterations in concentrations of corticosterone and thyroid hormones was observed. Application of the toxicokinetic data was used to predict IMI residue levels in the liver with reasonable results for some field exposure and avian mortality events. It would appear that some affected species of birds are either consuming larger quantities of seeds or exhibit differences in ADME or sensitivity than predicted by read-across from these data.

Seasonal expression and cellular distribution of star and steroidogenic enzymes in quail testis

Abstract: The quail Coturnix coturnix is a seasonal breeder with a physiological switch on/off of gonadic activity. Photoperiod and temperature are the major environmental factors regulating the spermatogenesis. To more thoroughly comprehend the steroidogenic pathways that govern the seasonal reproductive cycle, we have investigated the localization of StAR protein and steroidogenic enzymes (3β-HSD, 17β-HSD, P450 aromatase, and 5α-Red) as well as androgen and estrogen levels, in the testis of reproductive and nonreproductive quails. We demonstrated that StAR, 3β-HSD, 17β-HSD, P450 aromatase, and 5α-Red were always present in the somatic (Leydig and Sertoli cells) and germ cells (spermatogonia, spermatocytes I and II, spermatids, and spermatozoa). In addition, by western blot analysis, we demonstrated that 17β-HSD, P450 aromatase, and 5α-Red showed the highest expression levels during the reproductive testis compared with nonreproductive one. Accordingly, we also found that during the reproductive phase the highest titres of testosterone, 17β-estradiol, and 5α-dihydrotestosterone are recorded. In conclusion, our findings demonstrated that in C. coturnix: (a) both somatic and germ cells are involved in the local synthesis of sex hormones; (b) 17β-HSD, P450 aromatase, and 5α-Red expressions, as well as testicular androgens and estrogens, increased in reproductive quail testis. This study strongly indicates that the steroidogenic process in quail testis exhibits seasonal changes with the promotion of both androgenic and estrogenic pathways in the reproductive period, suggesting their synergic mechanism in the spermatogenesis regulation.

Pituitary adenylate cyclase-activating polypeptide in the testis of the quail Coturnix coturnix: Expression, localization, and phylogenetic analysis.

Abstract: To evaluate the involvement of pituitary adenylate cyclase-activating polypeptide (PACAP)/receptors system in the control of testis activity, we have investigated the expression and localization of PACAP and the distribution of its receptors in the testis of mature samples of quail Coturnix coturnix, and we have performed a phylogenetic analysis of PACAP in birds. Using histological, molecular, and bioinformatics tools, we demonstrated that (a) PACAP messenger RNA shows a high sequence identity with that reported in other birds studied so far and in other vertebrates. Furthermore, we showed that purifying selection acts on PACAP; (b) the PACAP peptide is present only in Leydig cells, whereas its receptors are localized within both Leydig and germ cells; (c) the synthesis of PACAP does not take place in seminiferous tubules. The role of PACAP in the control of spermatogenesis and steroidogenesis in birds is discussed. Finally, we talk about the phylogenetic and evolutionary relationships between PACAP in birds and in other vertebrates.

Skeletal development in blue-breasted quail embryos.

Abstract: The blue-breasted quail (Coturnix chinensis), the smallest species of quail with short generation interval and excellent reproductive performance, is a potential avian research model. A normal series of skeletal development of avian embryos could be served as a reference standard in the fields of developmental biology and teratological testing as well as in the investigation of mutation with skeletal abnormalities and in the study of the molecular mechanisms of skeletal development through genome manipulation. Furthermore, ossification sequence shows a species-specific pattern and has potential utility in phylogeny. However, data on the skeletal development of blue-breasted quail embryos are scarce. Here, we established a series of normal stages for the skeletal development of blue-breasted quail embryos. Cartilage and ossified bones of blue-breasted quail embryos were stained blue and red with Alcian blue 8GX and Alizarin red S, respectively. The time and order of chondrification and calcification of their skeletons were documented every 24 hr from 3 to 17 days of incubation, and a 15-stage series of skeletal development was created. Moreover, a comparative study with the Japanese quail (Coturnix japonica) demonstrated that ossification sequence differed significantly between these two species.

Secreting oviduct epithelial cells of Coturnix coturnix japonica (QOEC) and changes to their proteome after nonviral transfection.

Abstract: The quail oviduct (Coturnix c. japonica) is a natural candidate avian bioreactor, while the secretive quail oviduct epithelial cells (QOECs) are potential in vitro producers of recombinant proteins and vaccines. In view of the need for highly performing and transformable cell lines, QOEC may potentially act as an alternative bioreactor platform to the existing ones, for example, to the Chinese hamster ovary. The aim of this work was to characterize QOECs and their response to nucleofection with a nonviral plasmid DNA carrying the human interferon-α 2a gene (hIFNλ2a), in vitro. Primary QOEC cultures from laying quails (10-15 weeks old) were characterized by their proliferation rate, doubling time, and multilineage differentiation. Electroporation to cell nuclei (nucleofection) was used to deliver nonviral plasmid DNA containing a reporter GFP and hIFN under the ovalbumin promoter. The posttransfection analysis included polymerase chain reaction, Western blot analysis, and liquid chromatography coupled to tandem mass spectrometry. QOEC showed a typical epithelial characteristic in a primary 2D monolayer culture system and retained secretive potential up to the first passage. QOEC showed differentiation into osteoblastic lineage after stimulation. The nucleofection mean efficiency was low (2.3%). Differences of up to 10% in the proteomic profiles between nontransfected and transfected QOEC were found, the most important of these were related to the absence of keratins and cell-adhesion proteins in the transfected QOEC. Concluding, with the practical information provided here, QOEC have the potential to serve as an avian secreting cellular platform. QOEC may be further transformed to cell lineage to meet the requirement for a stable, electrocompetent, and transfectable model. The first proteomic comparison of QOEC delivered in this study showed, in the majority, a stable proteome of the nontransfected vs transfected QOEC.