Trout facts

[Coastrider]

A stupid question, yes. However I have never thought to ask this. When it come to diploid, triploid, reproductive/non-reproductive, I cant find info on what it all means and how to determine the difference. Ive seen Brian Chan id them on SFOTF but never close up id's. So, I know there are alot of people here that know alot about this field and would love to hear the FACTS. I assume diploid/triploid is 2 and 3 year old fish? Why are the triploids all non-reproductive? These are the kind of answers im looking for. Maybe point me to a book or a website I can read up on it. Thanks,Ed

[andy.larkin]

Diploid (2N) = Fertile
Triploid (3N) = Sterile

http://www.netregs.gov.uk/static/doc...er_1800113.pdf

[arrgh]

Diploid have the normal number of chromosomes(half from each parent) and can therefore breed. Triploid have half as many again and are mules(sterile) Sperm and ova are haploid(half the number of chromosomes of the functioning organism). Animals that don't waste energy on reproduction grow faster. That's why you cut the nuts off steers.

edit: Andy said it better than I could if I had read his link

[Bbulltrout]

As far as I know you can't look at a fish and say that it's Diploid or Triploid. You have to go to the stocking report to get this kind of information. Please correct me if I'm wrong.

[kevin200100]

In one of brian chan video he goes threw the difference n how to identify. Yoy can find torrent for it easily

[Some fly]

Both are unnatural

[professori]

Nothing unnatural about a diploid fish. It is merely a scientific word to denote an animal with 2 sex determinant genes (like all fertile, sexually reproducing animals). There are others on this forum who have better training in this field than I, but I will try to explain this as I understand it. Feel free to correct my errors.
In the case of sexually reproductive plants and animals, two parents are normally required. Each parent produces egg cells (ova) or sperm cells (in some cases an individual may produce both). The sperm or egg (germ cells) only contain 1/2 of the parent's genetic code and are referred to as haploids (from the greek for single). When the 2 germ cells unite their genetic content pairs up and the resulting pair (fertilized egg, embryo) is named a diploid (greek for 2). As part of this genetic pairing there is a specific set of chromosomes that carry a gene responsible for determining the sex of the newly formed organism. In the case of many species the Y chromosome carries maleness, so if one parent contributes a y chromosome and the other contributes an X chromosome, the offspring is male. If both parents contribute an X chromosome the offspring is a female. In both circumstances the offspring is a diploid.
In the case of triploid fish, at a very early stage in the development of the fertilized egg (diploid) the egg is exposed to high heat and very high pressure which causes (I don't pretend to know how) an extra X OR Y chromosome to develop. This produces a triploid (Greek for 3) female or male to develop. These animals are sterile and produce no eggs of sperm. Because food energy is not being utilized to produce germ cells, that energy is now utilized solely for growth. Animals produced in this fashion are definitely unnatural, but there is a very tiny number of triploids produced naturally as well, through random mutation.
As for being able to tell the 2 types apart, I would be very interested kevin if you could find that link. I have seen Brian on many shows and the only method I have ever seen him use to identify triploids is by the hatchery clippings done. In lakes like Roche, I have found hatchery clipped fish that were clipped on the adipose fin, the anal fin, and the maxillary, to identify the year as well as the triploid status of the fish. To the best of my knowledge there is only one way to determine if an unmarked fish is diploid or triploid, and that is with a knife just before cooking it.

[professori]

That's why you cut the nuts off steers.

And I thought it was just 'cause prairie oysters are so damn good!

[arrgh]

And I thought it was just 'cause prairie oysters are so damn good!

LOL, my sister nursed an old lady in her 90's who had been eating them for years until my sister told them what they were!

[typhoon]

Roche Lake stocking was unique because they were doing a study to determine if triploids were more likely to bleed from the gills when caught.
Thus, when Brian Chan is fishing Roche he can determine if the fish is diploid or triploid and what year it was stocked.
They stopped the special clipping on Roche several years ago so we are back to purely natural means to identify them.
Prior to a diploid fish spawning for the first time it is impossible to tell a diploid from a triploid externally. As stated above, once you clean it you can tell if it was a triploid because there will be no eggs or sperm, or something that looks like sperm but is orange in the belly.
Pennask/blackwater/fraser valley strain rainbows will typically spawn the first time by the time they reach 20" in interior lakes, so if you catch a fish 20" or larger you should have a pretty good idea if it is a triploid or not. Both females and males undergo physiological changes during spawning. Most obvious are the changes to the head and jaw. The female's head will elongate somewhat and the lower jaw will darken and often get a small bump at the end. The male's head will elongate significantly, including the lower jaw forming a kype. Both sexes will develop a much thinner, streamlined body shape.
Fish don't spawn every year so these characteristics will reduce after the first year, though they will look different than a fish that hasn't spawned.
A female triploid will have a relatively tiny head, and will generally be much fatter than diploid fish from that lake.
Most stocked triploids are female (because triploid males still undergo spawning behaviour even though they are sterile).
I don't think you can tell a triploid from diploid male.

Diploid Pennask Male


Triploid Female