Administration of LHRH analogues in various ways: Effect on the advancement of spermiation in prespawning landlocked salmon, Salmo salar

Claudine Weil (1) , L.W. Crim (2)

1 Laboratoire de physiologie des poissons
2 Marine Sciences Resarch Laboratory

During an experimental period of 12 days, the onset of spermiation, quantity of collectable milt, spermatocrit, plasma and pituitary gonadotropin hormone (GtH) were compared in control and LHRH analogue (LHRHa)-treated prespawning landlocked salmon. Des-Gly10-[D-Ala6]-LHRH ethylamide (D-Ala6-LHRH EA) was administered either by intraperitoneal multiple injections in saline or 40% propylene glycol or by a single intraperitoneal implant in silicone rubber. [6-(D-2-naphthylalanine)] LHRH (D-Nal (2)6-LHRH) was administered in a single cholesterol pellet. All the methods of administering LHRHa effectively accelerated the onset of spermiation and increased the volume of collectable milt. Study of the spermatocrit indicated that this increase is associated with an advancement in the production of spermatozoa and is not just due to sperm dilution. Furthermore, this increase in milt volume is related to an increase in plasma GtH. On the other hand, LHRHa treatments did not provoke any change in pituitary GtH content.

Mots clés: fish; spermiation; lhrh; salmonids; salmon; atlantic; spermatozoa

Mots clés: poisson; salmonidae; saumon; salmo salar; spermatozoïde; reproduction; production de spermatozoides; gonadotropine; gth

Domaines: Sciences du Vivant [q-bio]

Claudine Weil, L.W. Crim. Administration of LHRH analogues in various ways: Effect on the advancement of spermiation in prespawning landlocked salmon, Salmo salar. Aquaculture, 1983, 35, pp.103-115. ⟨10.1016/0044-8486(83)90078-9⟩. ⟨hal-01604306⟩