Induction of precocious maturation in masculinized Atlantic salmon by treatment with sustained-release LHRHa and testosterone

• Published in: Aquaculture international Vol. 6; no. 4; pp. 261 - 268
• Main Authors: Henry, J.C, McLean, E, Mayer, I, Donaldson, E.M
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Nature B.V 01-08-1998
• Subjects: Aquaculture; biological development; body weight; controlled release; Fish; gonadotropin-releasing hormone; gonads; masculinizing effect; maturity stage; Salmo salar; Salmon; spermatogenesis; Testosterone; weight
• ISSN: 0967-6120; 1573-143X
• DOI: 10.1023/A:1009255815481

The effect of treating immature, masculinized, Atlantic salmon, Salmo salar, with testosterone or [Des-Gly10] D-Ala6-LHRH ethylamide (LHRHa), either alone or in combination, over an 81 day period was evaluated as a method for accelerating maturation. Two sustained-release LHRHa implants were compared: ethylene vinyl acetate copolymer (EVAC) and silicone elastomer. Animals primed with testosterone did not express advanced spermatogenesis when compared against control salmon (p > 0.05). However, fish primed with testosterone, followed by sham, LHRHa EVAC, or LHRHa silicone elastomer implants expressed increased (p < 0.05) gonadosomatic index (GSI) when compared with values derived from day 0 of the study. Neither spermatogenesis nor GSI were affected when salmon were treated with LHRHa alone, irrespective of the vehicle employed. In contrast, spermatogenesis was significantly (p < 0.05) advanced in testosterone-treated fish, which were administered LHRHa by EVAC, when compared with groups that received individual treatment only. © Rapid Science Ltd. 1998[PUBLICATION ABSTRACT]