Several people have contacted me, interested in spawning their fish, maybe using hormonal induction (e.g. hCG, Ovaprim or carp pituitary extract), whether it be koi or silver perch, for example.
Some of the reasons for using hormones to induce breeding is so that you can get the right timing and the right pairings for selective breeding. Also, there is evidence to suggest that egg retention may be the cause of deaths during spawning (https://thefishvet.com/2012/01/11/egg-retention-may-be-the-cause-of-deaths-during-spawning/). Egg retention in koi may also predispose them to ovarian cancers. Hormonal induction will also maximise the fertility (hence, larger numbers of young) and it also means fewer unfertilised eggs hanging around that would otherwise attract bacteria and fungal disease. These are just some of the advantages of using hormonal induction to aid in the process of fish breeding.
The local weather has been up and down lately and even if people have had successful spawns, their fry may have suffered the recent cold shift in weather. But I’d predict that the weather from now on will be rather stable and warm and that it is a good time to spawn your fishes.
For koi, the water temperature must be able to be maintained above 21°C. Whereas, for silver perch, spawning occurs in
water temperatures of 23-30°C. Silver perch females mature in the third year at about 34cm and males mature males at 23 cm.
For a pictorial guide to using hormonal induction, see a previous post –https://thefishvet.com/2012/02/02/pictorial-guide-for-fish-breeding-using-hormones/
