This article first appeared in issue 632 of English Rinko magazine published on the 15th June 2015. For more information on Rinko magazine and how to subscribe please visit –

Fascinating Koi parent “Dump”

Your farm’s name is known to many Koi maniacs as the one that has been producing hit Showa. Do you have any troubles as a leading Showa breeder?

Isa: I’m afraid I am much overrated. There are many Showa Sanshoku breeders who are playing active parts in this field. I feel I have come to be able to produce them with a passing mark in quantity and quality. On the contrary, I haven’t produced any outstanding ones.

It’s not an easy task to provide a large number of more than average Showa Sanshoku in qualities, much less producing an outstanding one.

Isa: If the best one among a large number of better ones can be outstanding, I may be approaching the course I am aiming for.

Speaking of an outstanding Showa, we often see a picture of the Isa Showa that won the Minister’s award in the 53rd Niigata Nishikigoi Show, such as on your farm’s calendar and advertisements in magazines. Don’t you think that is one outstanding Isa Showa?

Isa: Well, it’s one of my best Isa Showa. It has splendid thick skin and beautiful scales as well.

Paid banner advert - put your ad here for just £50 per month

Isa Showa, Grand Champion 53rd Niigata Nogyosai Show

Isa Showa, Grand Champion 53rd Niigata Nogyosai Show

Was it conspicuous when it was very young?

Isa: No. I slightly noticed its beauty when it turned two years old. So I was very surprised to see it after it was scooped out of the field pond at the age of three. It had a certain aura and I felt the weight of it in my own hands at that time. It’s hard to express such a special impression.

The 53rd Niigata Nogyosai GC feeding in mud pond

The 53rd Niigata Nogyosai GC feeding in mud pond

That Showa is the very excellent one you can breed only after repeated selective breeding while having firm belief in the lineage of its parents. What is its mother?

Isa: The fish is not alive now, but we called her ‘Kimuchi’.

Did she produce many superior ones?

Isa: Unfortunately, only five superior ones, both male and female. They looked a little different from their siblings since they were very young. Most of Showa Sanshoku fry look unrefined, however, those of Kimuchi’s offspring looked gleamingly modern. They were, if anything, not my type, though.

Paid banner advert - put your ad here for just £50 per month

Those young Showa were already outstanding at a very early stage of their growth, weren’t they?

Isa: You may say so. I am at the brink of perfecting fruitful Showa Sanshoku pairing. One of my Showa parents I have now is called ‘Dump’. She is over one meter in length. Her offspring have a similar ambiance of Kimuchi’s refined ones, and the number of which is also very small. So I have been repeatedly breeding her in anticipation of good luck repeating itself.

When your dream comes true, you will dumbfound Koi enthusiasts again with those Showa.

Focusing on a specific factor when choosing Koi as koi parents

You mentioned introducing new breeds into your current Showa a little while ago. Do you sometimes come to a dead end when searching for candidates?

Isa: Searching for ideal candidates is not an easy task, so I am trying to search for Koi with a certain specific factor at a time.

For example?

Paid banner advert - put your ad here for just £50 per month

Isa: When I am looking for a Koi with refined Sumi markings I don’t care about its figure or Beni markings.

Koi’s mating season is approaching. Have you decided which Koi to mate?

Isa: We use artificial spawning and insemination methods, crossing one regular mating couple with one or two new males. I have trouble with those additional males.

What is your yardstick for choosing new males?

Isa: Since we’ve adopted artificial insemination, we can obtain conclusive evidence of crossbreeding with each Koi parent and use the results for next year’s crossing.

Do you have any special feature Koi parents?

Paid banner advert - put your ad here for just £50 per month

Isa: I am counting on a new Showa I purchased this year. It won the over 85bu Champion at the 49th ZNA International Koi Show.

Over 85bu Champion at the 49th ZNA International Koi Show

Over 85bu Champion at the 49th ZNA International Koi Show

What are its special features?

Isa: I was enchanted at first sight by its figure and the excellent texture of its skin.

The fish perfectly fits what you were searching for this time, right?

Isa: Exactly. It has an ideal figure so I’d like to reproduce that figure of the Isa Showa breed by using it as a new Koi parent.

What kind of lineage is the fish?

Paid banner advert - put your ad here for just £50 per month

Isa: Tokyo Kanshogyo raised it. From what I have heard, it is the offspring of a Dainichi bred female called ‘Shigeru Dai’ and a Maruju bred male of their old line. That lineage is the perfect one for our Showa.

New parent featured in magazine advert

New parent featured in magazine advert

Lineage is a very important factor in crossbreeding, right?

Isa: Yes, checking the lineage of Koi as Koi parents is necessary and indispensable for any Koi breeders. As you know, offspring from nearly related bloods has bad results.

It seems to be very difficult to come across an ideal Koi for a Koi parent.

Isa: And even if we find an ideal Koi, we can’t always obtain it. I am deeply grateful to the former owner of the Showa and the trader who mediated the deal between us.

Pairing of Koi parents

We often see professional Koi farmers at major Koi farm auctions. Finding ideal Koi for their Koi parents may be one of the reasons.

Paid banner advert - put your ad here for just £50 per month

Isa: In order to catch up with the current trend of producing large size Koi, it is inevitable to introduce other breeds as Koi parents. All Koi farmers are competing with one another for our new lineages which we’ve established through our efforts of repeated quality crossings.

What is your standpoint as a pioneer of establishing new Showa lineages?

Isa: Well, I started with a single Dainichi bred female because I liked its qualities very much. I still intend to maintain those fine qualities while improving the size of Koi. There are various hazards connected with crossbreeding. A single mis-crossing may lead to the worst possible scenario. Crossbreeding is a delicate matter, too.

Pairing of Koi parents sounds like cheerful work, but it is hard on many Koi farmers, right?

Isa: But it is our chance to show what we can do. When we decide which Koi to cross we can only rely upon our own senses and experiences.

Each Koi farmer is trying to establish a better lineage, which will be advanced by other Koi farmers, and more beautiful Nishikigoi are being produced daily as a result.

Paid banner advert - put your ad here for just £50 per month

Isa: I agree with you. When we were hit by the earthquake my male Koi parents were washed away. I was able to restart farming Nishikigoi thanks to many other Koi farmers’ aid. Each koi farmer’s pride in his achievements has made interchanges of Koi parents possible, I think. After engaging in Koi farming for a quarter of a century, I still have so many questions about my work. I am determined to improve Isa Showa and create appealing new lineages.

Well, thank you very much for sharing your time and letting us know the intricacies of your farm.



Many thanks to Shuji Fujita, publisher of Rinko magazine for authorising the re-publication of this content.  The content remains copyright of the original publisher and must not be reproduced in any way without their express permission, all rights reserved.

Paid banner advert - put your ad here for just £50 per month