Fish in captivity can show some dysfunctions, at different levels, in the physiological processes of reproduction, due to
the lack of synthesis or release of gonadotropins (GtHs) by hypophysis. As a consequence, a worsening of quality and
quantity of spawned gametes, or a lack of egg and sperm spawning, can be observed. The farmers can act on fish reproductive
cycle manipulating the environmental parameters of rearing, the diet, the genetics or using GnRH treatments.
Nowadays, they are used mainly GnRH, synthesized in laboratory as analogues. These releasing factors, naturally produced
by hypothalamus, let to overcome the technological and biological limits of the “traditional” hormonal treatments
with hCG, being more effective, cheaper and easily available on market. This article makes a historical survey of the conditioning
treatments for fish reproduction and also considers the future perspectives of these treatments, examining the
topics that research will have to focus, in order to make these treatments common worldwide, in any hatchery and for
each farmed species of finfish.
