A problem encountering in the intensive culture of some teleosts is the lack of final maturation and ovulation in captivity. On the other hand, in natural conditions the reproductive cycle is season depending. In the catfish culture, for instance, manipulation of environmental parameters have not been very successful in the control of the reproduct...
In fish the control of the pituitary maturational gonadotropin (GTH2) secretion in mainly under the influence of the gonadotropin releasing hormone (GnRH). This paper will deal with recent advances in the knowledge of the GnRH system in teleost fish, and on the others neuromediators wich can modulate positively or negatively this system or act dire...
In order to characterize trout Sertoli cells and germ cells obtained after testis dissociation and cell separation, we have studied their morphology, ultrastructure, survival, and ability to express differentiated activities in primary cultures. After dissociation, the fine structure of Sertoli cells does not differ from that observed in situ and o...
L'histologie des gonades de 187 mâles et 149 femelles de Myleus ternetzi pêchés dans des rivières guyanaises a été étudiée. Les stades et le cycle de la spermatogenèse ont été analysés à l'aide d'une méthode téréologique. L'ovogenèse a été étudiée et le stade de maturation de chaque femelle déterminé. La vitellogenèse est discontinue et au moins tr...
Interactions of catecholamines and GnRH in regulation of gonadotropin secretion in teleost fish
The organization of Gn-RH systems in the brain of teleosts has been investigated previously by immunohistochemistry using antibodies against the mammalian decapeptide which differs from the teleostean factor. Here, we report the distribution of immunoreactive Gn-RH in the brain of goldfish using antibodies against synthetic teleost peptide. Immunor...
