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I was wondering if an albino type cory would breed with a normal cory of the same species, im pretty sure they are the same species( the common ugly type ). But Im interested in breeding the Julie type. I was also wondering whats the best way to sex cories?

The female is bigger & wider from the male & i think that's the only way you can sex them.

Yes, Albino & "common" Bronze Corydoras will breed & just don't call them Ugly.


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the little guys can and will interbreed if you let them and they have no other choice of who to uhmm well you know ***blushes uncontrollably*** but for them to be the most happy and easiest to breed they should be with their own type

If you haven't been in chat when cali's corries are breeding, or haven't seen any corries getting a bit insane:%)I've seen my poor guys and gals try the T formation with both Lucky the Betta and the Neons in the tank...boy the look on their faces when the corries tried to spawn with them was priceless ROFLMAO at the thought...heidi



"I've got a great ambition to die of exhaustion rather than boredom." Thomas Carlyle

i have gotten all my cories to breed bronze, albino, spotted, and speckled

The majority of Albino Corys in circulation are an albino form of the Bronze Cory. Therefore, "crossing" an Albino with a Bronze doesn't actually count as hybridisation.

Because the mutation for true albinism (a fault in the gene that codes for melanin production) is single-factor recessive, this provides an excellent introduction to the world of genetics. Let M be the normal gene that codes for melanin production, and m be the abnormal gene. (It is a convention in genetics that a dominant gene is referred to using a capital letter, and a recessive gene is referred to using a small letter.)

Now, because the gene for albinism is recessive, the genotype of the albino individual will be mm. If you mate this fish with another whose genotype is MM, then the result will be ALL offspring whose genotype is Mm. Because the normal gene is dominant, the resulting individuals will look like normal Bronze Corys. But, they will all carry the gene for albinism.

If a pair of these Mm individuals are then mated, the resulting offspring will be divided as follows:

25% MM
25% Mm
25% mM
25% mm

Now, because the M gene is dominant, this means that 75% of the offspring will look 'normal', but 50% of them will carry the albinism gene (the Mm and mM individuals). Only 25% of them will carry two copies of the 'normal' gene. This leaves 25% of our offspring carrying the mm gene combination - these will be albinos.

Given that Bronze Corys produce around 200 eggs per spawning, you should find, if you raise the young of the second generation to the point where they manifest the adult colouration, then 25% of your offspring will be albinos.

Incidentally, such crossing of albinos with normal individuals, then producing a second generation of albinos from that line, is a good way of introducing genetic diversity into the albino strain. You will be introducing new genes from the 'normal' Cory pool into the albino pool, thus preventing too much inbreeding of the albino pool. This applies to other albino fishes where albinism is the result of a single-factor mutation as described above.

You'll soon know if your 'albino' fishes are the result of a more complex genetic interaction, however (as is the case with some fishes in which 'polygenes' play a role in colour) because the second-generation offspring will deviate from the 75%/25% split noticeably. However, the majority of albinistic creatures arise from a mutation in the melanin production gene, and I would suspect that Bronze Corys fall into this category.

Hope this helps ...


Panda Catfish fan and keeper/breeder since Christmas 2002

They hav'nt bred yet, i have been taking out warm water and adding coolers water, and feeding them well, I guess i have a male and female, actually my guess is i have 2 males and 1 female. I have two longer ones, and the other is a bit shorter and is more robust i guess?

Cali, I followed that quite well ***pats self on back for remembering her biology classes***

But, may I confuse things a bithow do we know when we buy a said "Bronze Cory" if it is actually a MM or a Mm? is it possible? or would we just have to breed them with said "albino cory" to discover the outcome?

Jeez this is where things get fun isn't it? I just loved studying genetics in high school and college:%)

heidi

"I've got a great ambition to die of exhaustion rather than boredom." Thomas Carlyle

Do i have a male and a female?

That's the trouble Heidi ... the MM and Mm fish look alike. You have to breed one with an albino to find out which is which. If your normal phenotype fish is has the MM genotype, all the offspring will look normal. If the normal phenotype fish is an Mm, then 50% of the offspring will be albino. That's how you know.


Panda Catfish fan and keeper/breeder since Christmas 2002

Anyone going to answer my question? lol

Fish Guy. We cannot say what you have as we cannot see them.



http://uk.pg.photos.yahoo.com/ph/s8xi5heh/my_photos
http://www.geocities.com/s8xi5heh/classic_blue.html

http://www.flickr.com/photos/corydoras/
Member of the Malta Aquarist Society - 1970.
http://www.maltaaquarist.com

In my experience, the only reliable way to determine the gender of a Corydoras Catfish is to see which one forms the stem of the 'T' in the T position. Usually, though this varies with species, the female is larger, and more full in the belly when seen from above. When containing eggs ready to be laid, the fullness is manifestly obvious from all angles. Males tend to be considerably slimmer. However, with some species, this is not easy to determine.

Oh, one feature of Pygmy Corys Corydoras pygmaeus that makes for an interesting method of determining gender is this: the female's eyes dilate noticeably during spawning!

Innes in his venerable tome also suggested that the males have slightly more angular pelvic fins than the females, though whether this is a reliable indicator of gender is a moot point. I can't say I've noticed a great difference, and I've now witnessed no less than eighty-one Panda spawnings. And filmed them on several occasions. If the difference in pelvic fin angularity was reliable, I would probably have homed in on it by now in all my still photos.


Panda Catfish fan and keeper/breeder since Christmas 2002