Spawning of Koi

This article, as written by Bob Barry, explains the Koi breeding process as described by Dr. Bertrelle Caswell, a renowned fish breeder and koi enthusiast. She has written in introduction to the popular book, Nishikigoi by Takehiko Tamaki. She is also an avid member of Koi clubs in the United States and is the editor and publisher of KOI USA magazine. In this presentation, she explains everything koi owners and breeders need to know before taking on such a task as spawning.

There are hazards that accompany koi spawning. These involve potential dangers to the fish’s health, color and patterns. Look at a koi fish’s pattern closer by looking at them under a compound light microscope. In some pond conditions, spontaneous spawning may occur and the owners may be oblivious to them. Often, fertilized eggs are eaten by the parents or are carried down the overflow of the pond. See how these eggs look like magnified by using a compound light microscope. In deliberate spawning, breeders should carefully plan each and every step of the process to prevent such harm.

For those who wish to breed koi for a commercial purpose, the article recommends that planning a year in advance is important. This will ensure that the fish have the best possible water quality, are healthy and that the right equipment is available. One example of the needed equipment is a microscope like the compound light microscope to monitor closely the breeding process. The selection of the fish for parents must be from the finest bloodline. Sturdy fish, those that are about 20 to 24 inches long are preferred. The resulting fish usually has a similar scale pattern and have the same classification as the parent fish.

Breeders have different procedures for breeding, but one aspect stays the same. The age of the fish is one recognition that is constant to all breeders. The breeder must recognize the right time. The ratio of the fish is also a vital aspect in the breeding process. The article recommends that the ratio of male to female should never exceed 2:1, granting that the fish that are being bred are of the same size.

Environmental factors such as the temperature and the season play an important role in the breeding of koi as well. In Southern California, April to July are the ideal months for spawning. However, koi has been bred with successful results as early as February or March and sometimes, as late as August. Hatching periods are preferred to be in May or June, so that the resulting offspring may have time to grow and adjust before the winter season commences and because at this time of the year, live feed is available and that the possibility of a stronger hatch has been known to occur.

Dr. Caswell explains in great detail what preparations need to be achieved before spawning koi takes place. She also describes the ideal nesting materials for the maximum hatching of the koi. She also illustrated how to spot a female koi that is bloated with eggs and how to care for and handle them. Housing of the koi is also a major factor in the breeding process. Dr. Caswell explains the proper type of pool and its contents that should provide the koi with the best conditions possible for spawning. She also explains that timing, nutrition and the development of the baby fish as a crucial must-know for every koi owner and breeder. More on this topic.