Aquarium & Tropical Fish Site
Tropical Fish Forums
Aquarium fishkeeping around the world!
 
ChatChat  HelpHelp   Search BoardSearch Board   MemberlistMemberlist   UsergroupsUsergroups 
 ProfileProfile   Check your private messagesCheck your private messages   Log inLog in   RegisterRegister 
Behind the Curtains of Responsible Fish-Keeping
Goto page Previous  1, 2, 3, 4, 5, 6, 7  Next
 Forum Index > Aquarium Science  Reply to topic   Post new topic
Author Message
DF Bobo
Exemplars


Joined: 23 Jan 2006
Location: Canada

PostPosted: 2007.12.19(Wed)15:01    Post subject: Reply with quote

well, my point in that was that sometimes people need to out cross their lines and it would be convenient for them to get wild specimens if they didn't have other captive strains easily available to them or something like that.

also, who thinks that it would be a good idea for this board to build a directory of private breeders?
_________________
New to fishkeeping? Click the banner

Back to top
View user's profile Send private message Visit poster's website
CAllain
Regulars


Joined: 05 Jun 2007
Location: Berkshire, England

PostPosted: 2007.12.19(Wed)15:10    Post subject: Reply with quote

Quote:
who thinks that it would be a good idea for this board to build a directory of private breeders?


Me!!! But if it was done, it'd have to be separated by area... eg. by country then by state/county/province/region.

And, if you were going to go for a directory of private breeders, why not also a directory of aquarist clubs in the same way?

The downside may be that this could end up being cluttered...
Back to top
View user's profile Send private message Visit poster's website MSN Messenger
number6
Moderators


Joined: 07 Feb 2003
Location: Ontario, Canada

PostPosted: 2007.12.19(Wed)15:41    Post subject: Reply with quote

DF Bobo wrote:
well, my point in that was that sometimes people need to out cross their lines
My point is that this was once thought to be necessary, when now there is strong evidence that says this is a counterproductive action.

Right now, there appears to be no reason to outcross to unrelated fish.
Ever.

I realize that inbreeding depression exists, but you have to note that the effects of inbreeding does seem to be virtually negligible in most natural inbreeding populations.
_________________
"Just don't look in my fish room honey... it's just better for all of us. "
Back to top
View user's profile Send private message
Psyfalcon
Advisors


Joined: 14 Feb 2003
Location: Oregon

PostPosted: 2007.12.19(Wed)15:51    Post subject: Reply with quote

Even in some of those guppies?

Cichlids seem to be fine with inbreeding, perhaps because there is often fry predators when they are kept by hobbiests and not breeders, but guppies... especially the metallic ones look terrible!
_________________
Fish, Volcanoes, and Photography
PhotoBlog
Back to top
View user's profile Send private message
number6
Moderators


Joined: 07 Feb 2003
Location: Ontario, Canada

PostPosted: 2007.12.19(Wed)17:39    Post subject: Reply with quote

line breeding often includes so many "breeding" errors that are expressed through inbreeding.

This is why it sure looks like inbreeding causes a problem.

Here's the dilema... if you inbreed, you express the problem. If you outcross and mask a problem, you could line bred to eliminate all the carriers of the negative allele, but how can you id the carriers... in fact, all you've suceeded in doing when you masked the allele was to spread it into the next generation, and the next and the next...
_________________
"Just don't look in my fish room honey... it's just better for all of us. "
Back to top
View user's profile Send private message
Luna
Regulars


Joined: 11 May 2007
Location: St. Louis, MO, USA

PostPosted: 2007.12.19(Wed)22:22    Post subject: Reply with quote

And MY point was for the invigoration of the gene pool. Laughing I don't believe in masking bad genes, but providing new and/or stronger genes that will keep the population connected to their wild counterparts. I'm not imagining something like dog breeding or guppy breeding here, looking for good appearance or a certain characteristic. Rather, it keeps the breeding more natural. Maybe that so-called bad gene is there for a reason, you know?

I dunno, it makes sense in my head. Laughing I can totally understand wanting to make a negative trait more noticeable in order to avoid it, but there could be plenty of new, positive traits in the wild that would make your captive population stronger.
_________________
--Kathy--
Back to top
View user's profile Send private message Yahoo Messenger AIM Address
number6
Moderators


Joined: 07 Feb 2003
Location: Ontario, Canada

PostPosted: 2007.12.20(Thu)8:45    Post subject: Reply with quote

outcrossing does not improve fitness of a captive population in the long run though...

You do mention the only valid reason for an outcross, and that is to obtain a new gene not present in a captive gene pool. However, you then blurred the line between what is a new gene and then implied getting a stronger version of some defective gene present...

Here's a valid out cross...
Captive Convict bloodlines don't have a very large humped head... some wild individuals are found with larger humps... we use those to obtain larger humps in our captive bloodlines.

Now here's a bad out cross plan...

Our convicts are having some fertility issues... numbers of fry produced are dropping down to about 20 per pair... we buy a wild caugt, mix it into our bloodline and now the fertility rate is back up to normal and we get larger batches.


Do you see the difference?
_________________
"Just don't look in my fish room honey... it's just better for all of us. "
Back to top
View user's profile Send private message
Cardinal Tetra
Regulars


Joined: 16 May 2007

PostPosted: 2007.12.20(Thu)15:09    Post subject: Reply with quote

My main concern with taking from the wild was dircted towards marine species. Should have included that Confused
Back to top
View user's profile Send private message
nikelodeon79
Regulars


Joined: 08 Nov 2007
Location: Wisconsin, U.S.A.

PostPosted: 2007.12.20(Thu)15:48    Post subject: Reply with quote

I'm not educated enough on the subject of wild caughts to take one side or the other. It does seem as if there an amount of pride in having them... I know I'm pretty pumped about the F1s I'm should be receiving soon. Personally, I'm happy they're F1s instead of F0s because I feel like they'll be happier in my tank not having experienced the great big lake. Wink

For some reason talk of wild caughts from the ocean makes me think of "Finding Nemo." Laughing
Back to top
View user's profile Send private message Send e-mail Visit poster's website MSN Messenger Yahoo Messenger AIM Address
number6
Moderators


Joined: 07 Feb 2003
Location: Ontario, Canada

PostPosted: 2007.12.21(Fri)7:50    Post subject: Reply with quote

Cardinal Tetra wrote:
My main concern with taking from the wild was dircted towards marine species. Should have included that Confused


Ah, I would agree on the controlled part then, but not eliminated.
There is a way to harvest fish in the larval state and captive rear salt water fish.

This is a non-destructive, non invasive way of taking salt water fish at a phase of normal high mortality and obtaining fish for the hobby.

It is more expensive than destructive fishing practices, but makes for very hardy fish...

How we take from the wild should be regulated and controlled....
_________________
"Just don't look in my fish room honey... it's just better for all of us. "
Back to top
View user's profile Send private message
Display posts from previous:   
 Forum Index > Aquarium Science All times are GMT - 6 Hours Reply to topic   Post new topic
Goto page Previous  1, 2, 3, 4, 5, 6, 7  Next
Jump to:  
  You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2008 phpBB Group

oF <=> oC in <=> cm G <=> L