"Jumbo" Tosai

[Sangreaal]

Alrightie...what are jumbo tosai all about? What is the difference between a jumbo tosai and a regular tosai? Is it a bloodline that produces giant koi? Is it an oxymoron like jumbo shrimp?

Inquiring minds gotta know,

Marie

[aquitori]

Quote: Originally Posted by Sangreaal Alrightie...what are jumbo tosai all about? What is the difference between a jumbo tosai and a regular tosai? Is it a bloodline that produces giant koi? Is it an oxymoron like jumbo shrimp? Inquiring minds gotta know, Marie

Jumbo Tosai is what it is a "Jumbo Tosai". It's a fish that has been fed more than the other tosai, a tosai that has been pushed to grow big.

[Sangreaal]

But other than feeding for accelerated growth, these are the same genetics as other tosai? Not something that will grow much huger in the end?

M

[aquitori]

First off, a tosai is a tosai regardless of size, but by age. The breeders felt they can sell a bigger far younger fish for the same or more than a nisai. You have 2 fish(equal in quality) from the same spawning. Tosai A is put in a lower stocked pond, but fed 6 times a day. Tosai B is put in a higher stocked pond, but fed 3 times a day. Given the water conditions are the same which fish will grow bigger and then labelled "Jumbo" Tosai? No brainer Tosai A.

In the end the only difference in the 2 is one had more of a head start than the other. Will Tosai B catch up in size to Tosai A. Yes. How long will it take? Who knows.

[keokoi]

Good Info...


So in Jumbo Tosai its my understanding that yes the body grows very fast So tosai A is bigger than Tosai B.. But is the outside showing the whole ballgame? Are the internal Organs and such growing or taking on more stress to feed the bigger body of Jumbo tosai..

[aquitori]

Quote: Originally Posted by keokoi Good Info... So in Jumbo Tosai its my understanding that yes the body grows very fast So tosai A is bigger than Tosai B.. But is the outside showing the whole ballgame? Are the internal Organs and such growing or taking on more stress to feed the bigger body of Jumbo tosai..

Good question Keokoi....We can only see the outside of the fish, if we take alook at the internal works of the tosai(s) they are pretty much the same size.

[Sangreaal]

It would be interesting to compare pics of jumbo tosai and regular tosai from the same spawn. From what I understand, color (hi, sumi) doesn't develop very fast (if at all) while a koi is in a growth stage. Would a jumbo tosai, therefore, suffer a setback in color because of being grown out faster, only to catch up later when growth slows and the koi matures? Or would color intensity be sacrificed/exchanged for rapid growth?

M

[MikeM]

There was a time when jumbo tosai were the ones separated from the herd by the breeder for special handling due to perceived superior characteristics and intended to go back to the mud a second year. Some of these may have actually been genetically-programmed to be larger. But with expanded facilities and technology (e.g., heat) it has become feasible for breeders to grow more of them and I think it has become more a marketing effort to give consumers what they want. The identifiably superior tosai are not going to be sold in batches for the overseas markets, whether jumbo or not. I think the one benefit a typical hobbyist gets from acquiring a jumbo tosai compared to a "normal" one is simply that you can see what you are getting a bit better... flaws in pigment quality or finnage etc are going to be much more noticeable. With the better breeders it may be an indication that the breeder deemed the fish better than the ones sold off in the Fall right after the harvest and deserving of some extra expense to grow a few inches more. Whether that justifies the higher price is something each person has to decide.

...Have you noticed that the term "jumbo tosai" varies in meaning from breeder to breeder? To some, it means a tosai over 14". For others, it can be over 10". A few years ago I had a flock spawning in late March. One of the fry survived and the following January I took him to a local club meeting to find a new home. He was about 18" and worth exactly what I got for him ... a smile and a thank you.

[johnsmith]

Jumbo tosai is a genetic manifestation. Or jumbo tosai is an illusion.


The real deal is a rarity. That is why it is both valued and expensive and usually never parted with as it will become much more valuable with age.

The 'illusion' is a marketing gimmic. You can force a tosai to grow and make it look like the former example ( for a time anyway).

Thirdly, there is jumbo genetics, where many of the spawn looks and carries the trait for size. This is real also and expensive and depending on the individual, a gamble as to outcome. Think about this- in every jumbo production, there is a genuine JUMBO that is larger than its siblings- it is never for sale. And in every jumbo line there are runts. Is your head spinning yet?

Buy what you like, buy a sound fish and buy a fish from quality lines- leave the rest to the marketeers.
JR

[PapaBear]

Jumbo Tosai's (aka tobies most of the time) are easy to spot in the fry tank. They're the ones swimming around with their smaller siblings tails hanging out of their mouths

I agree wholeheartedly with the asessments posted thusfar. Marketing gimmicks diverting attention away from the genepool. For a Jumbo to be a true Jumbo it needs to have the "bones" for it. Spotting the bone structure in the fry pond takes a practiced eye just like spotting pattern potential on a 1" fish.