Talk:Corydoras paleatus

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swallowing milt[edit source]

I removed the part about the female swallowing the males milt because it is not refrenced and frankly sounds silly. If anyone can refrence it feel free to put it back in.--Tash 00:24, 1 February 2009 (UTC)

ok. I found one article from 1995 called "Sperm drinking by female catfishes" http://www.springerlink.com/content/l62w27k5j077746g/fulltext.pdf?page=1 . However you can only see the first page for free (which also states "Despite numerous observations of spawning behaviour, how eggs are inseminated is still unknown."). Without the full article I just don't think this can be used as a refrence. (and even if I paid for it I would still hesitate to use a refrence that other people would have to pay to check out for themselves) --Tash 02:42, 1 February 2009 (UTC)


Sounds like bull to me too... --Brian 07:06, 1 February 2009 (UTC)


Then you'd both be wrong. :-) It is well known and documented that when Corys mate and assume the T-Position, that the male positions his vent against the females mouth and the female swallows the sperm and it passes down to her vent where it fertilises her egg.

http://www3.interscience.wiley.com/journal/118504651/abstract?CRETRY=1&SRETRY=0 or better:

http://nationalzoo.si.edu/Publications/ZooGoer/1998/6/amazoniafishatnatzoo.cfm

"What happens next has long been a mystery. Exactly how do the sperm reach the eggs with the pair in the T position? In an ingenious study, Masanori Kohda and coworkers at Osaka City University in Japan solved the puzzle. To follow its course, they dyed the sperm of males and found that the female swallows the sperm while she is in the T position. It then passes through her digestive tract and exits her vent near her newly laid eggs four or five seconds later. Unlike many fishes, females do not dump their eggs into the water. Rather, they release them into a ventral fin pouch. After they are fertilized by sperm that have passed through her digestive tract, she carries the eggs to a suitably cleaned spot and deposits them there."

This is the paper:

http://tripatlas.com/Corydoras#ref_5

Sperm drinking by female catfishes: a novel mode of insemination, , Masanori, Kohda, Environmental Biology of Fishes, 1995

This publisher mentions it in the Abstract:

"We report on unique reproductive behaviour and a new mode of egg insemination in a small catfish Corydoras aeneus (Callichthyidae). A male courts a female by presenting his abdomen to her. Before releasing eggs, the female attaches her mouth to the male's genital opening and directly drinks his sperm. The sperm pass through her intestine and are discharged together with eggs into the ‘pouch’ formed by her pelvic fins. Thus, eggs are mixed with fresh non-dispersed sperm in an enclosed space, ensuring effective insemination. This mode of insemination is novel to fishes, but is likely not restricted to catfishes of the genus Corydoras."

http://www.metapress.com/content/l62w27k5j077746g/


I think that is enough of a reference? :-)


I've added a embedded article on this which can be put on any Cory page in the Corydorus category.

See {{Category:Corydoras/Spawning_behaviour_of_Corydoras}} - Category:Corydoras/Spawning_behaviour_of_Corydoras


--Quatermass 19:58, 1 February 2009 (UTC)



"I think that is enough of a reference?" nope. Not for me. Like I said before I can't read the article for less then $34 so how do I know what it says? ;) I would love to read it though. And to see further studies/presentations/videos but I can't seem to find ANY available research on the subject. --Tash 23:15, 1 February 2009 (UTC)


Well unfortunately not everything on the Internet is free and not everything which is copyright protected is available online. So you'll need to find $34. :-) Or ask someone who is in University to get a copy. Students often get access to these sort of papers freely.

But it still doesn't help the reference does it? If you did read the paper and put a link to it. Someone else coming along a year from now may think like you and say "How can I believe that reference if I can't read the paper?". How does one verify a reference to a paper that the reader can't read without paying?

My personal view is that if the reader cares that much, they need to pay up or find an alternative way to read it? On this Cory spawning subject there does appear to be a lot of web sites referencing this paper. Doesn't that count for something? (OK, they could all be wrong I know ;-) Why not ask on Corydoras forums if someone has this paper? Obviously it may be illegal for them to give you it.... But you can ask. :-)


--Quatermass 15:10, 2 February 2009 (UTC)


yet another reason to give my husband as to why I need to go back to collage and get a BS in biology ;) (at least that way I could write off the $34 as student expensises right?). :lol: I do find it intresting that this is the only study done (over a decade ago) when it seems to be such a big debate among cory breeders. I did find this http://www3.interscience.wiley.com/journal/118483259/abstract?CRETRY=1&SRETRY=0 which mentions in the abstract "so called 'sperm drinking' type of mating". But since I can't read it either I can't tell what they mean by "so called". But it doesn't seem that they did any experiments, they are just reporting on other papers. and just because a website uses it as a refrence doesn't mean they have read it either. ;) Personally I don't feel comfortable using something I haven't read as a refrence, weather the reader can read it or not. Here is a great 'how to' article on cory breeding by Ian Fuller. He specifically states that he won't get into the debate on how fertilization occurs. http://www.planetcatfish.com/shanesworld/shanesworld.php?article_id=312

I just wanted to come back and say that I spoke with someone who did read the paper. They said that in the experiment they used a syringe to release dye near the males vent during mating. The dye disappeared and they assumed that it was swallowed. To me this doesn't sound like a valid experiment. Again though I would need to read the article to verify if that is really what it says. Perhaps a section on the cory breeding page referencing the article and mentioning the debate would work? --Tash 03:17, 1 January 2010 (UTC)