Profiles of plasma gonadotropin and 17β-estradiol in the common carp, Cyprinus carpio L., as related to spawning induced by hypophysation or LH-RH treatment

Claudine Weil (1) , Alexis Fostier (1) , L. Horvath (2) , Sylviane Marlot (1) , M. Berscenyi (2)

1 Laboratoire de physiologie des poissons
2 Warm Water Fish Hatchery

Plasma gonadotropin (GTH) and 17β-estradiol (17β-E2 ) levels and oocyte stage were studied in C. carpio after classical hypophysation (two intraperitoneal pituitary injections of 0.3 mg/kg and 2.7 mg/kg at a 12-h interval) or LH-RH treatment (two intracardiac injections of 3μg/kg at a 3-h interval). After the first pituitary injection of LH-RH treatment, GTH increase was followed by a significant increase of 17β-E2 7 h after the injection. The higher GTH levels after the second pituitary injection did not increase that secretion. After classical hypophysation, 50% of the females ovulated. There was no difference between spawning and non-spawning fishes in relation to hormonal parameters. LH-RH treatment only induced a shifting of the nucleus.

Mots clés: Fish; Cyprinidae; Carp; Cyprinus carpio; Gonadotropin; Hypophysation; Hormonal treatment; Reproduction

Domaines: Biologie de la reproduction; Alimentation et Nutrition; Biologie du développement

Claudine Weil, Alexis Fostier, L. Horvath, Sylviane Marlot, M. Berscenyi. Profiles of plasma gonadotropin and 17β-estradiol in the common carp, Cyprinus carpio L., as related to spawning induced by hypophysation or LH-RH treatment. Reproduction Nutrition Développement, 1980, 20 (4A), pp.1041-1050. ⟨10.1051/rnd:19800612⟩. ⟨hal-00897706⟩