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Female Chickens (female + chicken)
Selected AbstractsExpression of AMH, SF1, and SOX9 in gonads of genetic female chickens during sex reversal induced by an aromatase inhibitorDEVELOPMENTAL DYNAMICS, Issue 2 2001Séverine Vaillant Abstract Aromatase inhibitors administered prior to histological signs of gonadal sex differentiation can induce sex reversal of genetic female chickens. Under the effects of Fadrozole (CGS 16949A), a nonsteroidal aromatase inhibitor, the right gonad generally becomes a testis, and the left gonad a testis or an ovotestis. We have compared the expression pattern of the genes encoding AMH (the anti-Müllerian hormone), SF1 (steroidogenic factor 1), and SOX9 (a transcription factor related to SRY) in these sex-reversed gonads with that in control testes and ovaries, using in situ hybridization with riboprobes on gonadal sections. In control males, the three genes are expressed in Sertoli cells of testicular cords; however, only SOX9 is male specific, since as observed previously AMH and SF1 but not SOX9 are expressed in the control female gonads. In addition to testicular-like cords, sex-reversed gonads present many lacunae with a composite, thick and flat epithelium. We show that during embryonic and postnatal development, AMH, SF1 and SOX9 are expressed in the epithelium of testicular-like cords and in the thickened part but not in the flattened part of the epithelium of composite lacunae. AMH and SF1 but not SOX9 are expressed in follicular cells of ovotestes. Coexpression of the three genes, of which SOX9 is a specific Sertoli-cell marker, provides strong evidence for the transdifferentiation of ovarian into testicular epithelium in gonads of female chickens treated with Fadrozole. © 2001 Wiley-Liss, Inc. [source] Roles of antioxidants on prolonged storage of avian spermatozoa in vivo and in vitroMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 3 2003Christelle Bréque Abstract This review focuses on natural and assisted prevention against lipid peroxidation in avian spermatozoa. The presence of high levels of n-6 polyunsaturated fatty acids (PUFAs) in the plasma membrane creates favorable conditions for the formation of peroxidative products, a major cause of membrane damage which may ultimately impair male fertility. However, a complex antioxidant system involving vitamin C, vitamin E and GSH is naturally present in avian semen. Coupled with a battery of enzymatic defenses (e.g., SOD, GSH-Px either Se- or non-Se-dependent), this system acts to prevent or restrict the formation and propagation of peroxides. The presence of specialized sites dedicated to prolonged sperm storage in avian females raises the question of durable protection of sperm membranes against peroxidation. Preliminary observations have revealed the presence of a specific antioxidant system at these sites in which vitamin C could exert a major role. From a practical standpoint, the extensive use of artificial insemination in poultry, along with the emergence in some species of workable techniques to cryopreserve spermatozoa, demand better control of peroxidation occurring in the plasma membrane of spermatozoa before or during storage. Dietary supplementation with vitamin E is effective in limiting lipid peroxidation of sperm plasma membranes, both in chickens and turkeys. In addition, organic Se with or without vitamin E stimulates Se-GSH-Px activity in seminal plasma. Preliminary observations in female chickens have also revealed the effectiveness of dietary supplementation with vitamin E, organic selenium or both to sustain fertility in aging flocks. Mol. Reprod. Dev. 66: 314,323, 2003. © 2003 Wiley-Liss, Inc. [source] Changes in peroxisome proliferator-activated receptor gamma gene expression of chicken abdominal adipose tissue with different age, sex and genotypeANIMAL SCIENCE JOURNAL, Issue 3 2009Kan SATO ABSTRACT Peroxisome proliferatior-activated receptor gamma (PPAR,) is a transcription factor that regulates adipocyte differentiation, and the activation of PPAR, increases fat deposition in growing chickens. The aim of the present study was to investigate whether the levels of PPAR, gene expression were related to fat pad weight in abdominal adipose tissue in growing chickens with different genotype and sex. Body weight and abdominal adipose tissue weight in broiler chickens (Ross strain) were higher than the other genotypes (Road Island Red, White Leghorn, and Japanese native poultry (Tsushima)) at 3 and 5 weeks of age. PPAR, mRNA expression in abdominal adipose tissue tended to increase with age, as evidenced by higher expression levels at 5 weeks than at 1 week of age in all sex and genotype of chickens. In broiler chickens, the PPAR, expressions were significantly higher than the other genotypes. PPAR, mRNA expression levels in abdominal adipose tissue of female chickens rapidly increased at 3 weeks, and were unchanged until 5 weeks, while those in male chickens gradually increased until 5 weeks. In addition, abdominal adipose tissue weight was correlated with PPAR, expression levels. These results demonstrated that PPAR, gene expression is a useful marker of fat deposition in chickens, suggesting that PPAR, is a key factor of fat accumulation in chicken abdominal fat pad. [source] | ||||||||||