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View Full Version : TO DNA SEX DISCUS OR NOT TOO?



Ben
Thu Feb 03, 2005, 01:43 AM
Lets all find out wether we would do it or not!
i guess this poll would only be for people who breed discus or would intend to, as it would be pointless to vote if you did not care what the sex of the discus would be.

Merrilyn
Thu Feb 03, 2005, 03:48 AM
I disagree with dna sexing on two grounds. First the stress to the fish involved is going to be a huge factor. We could not do it at home, so it would be necessary to take the fish to a vet. Are you happy to sit in the waiting room with your distressed discus in a bucket while you wait your turn, amongst all the dogs and cats.

Secondly, do you really need to know? After all, the discus knows what it is, and just putting a male and female together in a tank is no guarantee of getting a compatible pair.

I guess it might be important for big commercial breeders selling a guaranteed male or female, but for us, no.

Sean
Thu Feb 03, 2005, 04:16 AM
I may be wrongggg, DNA analysis for determing gender is not available at the moment and if it were I am sure it would be much more than $50.00 a fish. The taking of a sample would not require going to a vet though. It is a nice idea and I would like to know the sex of juvenile fish before I bought them for compatability reasons as well as breeding purposes. With the sequencing of the zebra fish genome there maybe a possibility of this service, but as far as I can tell there has not been male specific gene markers determined for zebra yet either. The zebra (danios) are the fish that researchers use to study embryo development and currently it is the fish that the genetics of is mostly known. Governments are willing to spend money on the development of DNA techniques for rare species - so it maybe possible to test birds for as little as $50.

Ben
Thu Feb 03, 2005, 05:00 AM
Thanks guys for your feed back!
its all very interesting to hear what people have to say!

Merrilyn,
in my opinion, it would make the pairing up a lot faster by having a confirmed male and female in thier own tank than waiting for a male and female to pair up naturally in a tank of say 6 or 7 fish.


Sean, Rather than a Goverment funded Geneticist, lets say there was someone who worked privaltly and could easily do a dna test on fish?
what would be your thoughts then?

As for birds, i know that all birds can be DNA sexed except for the family (ratites) of emu's and ostriches as they have an ancient chromosone which can not be unravelled and worked out!

Sean
Thu Feb 03, 2005, 05:41 AM
The problem is not getting someone to do the test for you - I would do it for free :) , the problem is in identifying a gene or a DNA sequence that is only present in the male discus. The place to start is with the zebra fish genome and .... I will do some searching and send an email to some researchers to see if anyone can send me a sequence and let you know - It is amazing how much time Discus can take up :!:

Ben
Thu Feb 03, 2005, 05:44 AM
cheers Sean!
that would be great!
another piece of the puzzle........

the_oracle
Thu Feb 03, 2005, 05:55 PM
I'll vote No to discus sexing. If you can determine sucessfully their sex even at young age, then I guess it just takes away the thrill of raising them to adulthood................

Regards,
Sanie.

Sean
Fri Feb 04, 2005, 05:33 AM
Ben, I was at first negative with regard to the DNA testing, but am coming around to your way of thinking. The cost is the real issue for me. I am surprised at the negative comments and wonder how much of it is related to negative (ignorant) press etc. regarding DNA technologies and genetic testing. The stress on the fish would be much less than that of bullying dominant fish in the tank or moving a fish to a new tank. The benefits would far outweigh any negative effects of taking a small bit of tail fin. Part of the exciting part of this hobby is raising fry which in my opinion is challenging and surely buying fish of a known sex (so long as it is not cost prohibitive) would help enormously. LFS are never too happy about taking back your excess males or females in my experience, and quite often will say 'I am pretty sure that is a female' when they have no idea. I hope you keep up the interest in this topic.
Cheers
Sean

flukes
Fri Feb 04, 2005, 07:42 AM
Iam with Merylin, although it would be good, it would ware off fast.
You say the stress would be the same as a bullying fish or introducing a new fish, and how many topics do we see posted about stopping bullying or introducing a fish into a tank with minimal stress.

My point is you can normally work it out after the first batch of eggs, even before then there are certain signs which can give you a good idea of what sex the fish is..

Although i do find it intresting i might use it once for an extreme circumtance, but other than that i dont think its that practical.

Ben
Fri Feb 04, 2005, 09:51 AM
Flukes and Sean thanks for your feedback!
its great to hear your different opinions, i guess thats why we have this forum!

Flukes, can i quote you:

"My point is you can normally work it out after the first batch of eggs, even before then there are certain signs which can give you a good idea of what sex the fish is.."

The whole idea about DNA sexing is that we do not have to wait until those "first batch of eggs" or even study the fish before there first batch, even then this is not accurate!

As far as bieng practical, all of us discus keepers and/or breeders go to huge inpractical ways or methods in keeping our discus! so i guess we have to look at whats practical? is it easier to study the subject fish for many hours or cut a piece of fin and either post it to the labratory or drive it there?.

yes i do enjoy watching my discus courting in thier own romantic rituals, but i also would like to know %100 who is the boy?/s or who are the girl/s.

cheers,
Ben

Ben
Fri Feb 04, 2005, 10:05 AM
Sean, Thanks again for your feedback!
Have you seen the pol so far?
i have not put my vote in as i believe that would be too bias. Without sounding like i am going in a circle, you said that the cost would be an issue for you, well have a quick read on my other post on the same subject, if we work out the cost of maintaining each individual fish through out its life, lets say seven years, i guess an added $50- to the total would be small!, look at the cost of filters, tanks etc, what about the electricity or gas used to heat the tank/s (except far north queensland!)
and these days water is not free either? it all comes at an expense.
What i am trying to say is that my discus are in the same category as my pet dog, if i pay $60 to get it vacinated or pay $12- a month for front line or those occasional vet trips that cost a fortune!
and i try to give them the best i can offer, even my love.
So far i can see a lot of people saying yeah, well its too expensive,
What price to we put on our discus?
i guess that could be a new topic in its self!

DiscusMad
Fri Feb 04, 2005, 01:35 PM
LET THEM HAVE THERE PRIVACY UNTILL THEY WILL SHOW YOU THEMSELVES

Ben
Fri Feb 04, 2005, 09:47 PM
I would like to hear of the opinion from Kev at slippery little suckers? He sells a lot of fish,


1/ would it have a greater impact on sales?

2/ would buyers pay an extra $50 per fish that came with a wrtten statement and garauntee that it was male or female?

3/I guess if people had the option, it would mean more buisness?

Ben
Fri Feb 04, 2005, 09:54 PM
Discusmad thank you for your feedback!

In an age of technology we should give everyone an option, you can choose to let your discus pair naturally while i might get them dna sexed.

Thats the point i am trying to make, we should have the option in dna sexing discus.

A pregnant woman can have an ultrasound and choose wether she wants to know if its a boy or a girl. She could also have the greatest supprise after 9 months or she can find out earlier and start to make plans, i support both, but in the end we have a choice!

Some pet owners have thier dogs or cats micro chipped, that costs more than $100- to have done, but once again, pet owners have the choice.

cheers,
Ben

DiscusMad
Sat Feb 05, 2005, 12:01 PM
wouldn't an ultra sound to the sex organs be a lot cheaper and less stress to the fish or even test the poo of the fish than take a sample of the fish body.


but saying all of that my coment above was just a joke

kalebjarrod
Sat Feb 05, 2005, 10:07 PM
i know of some people who can pick the sex with 90%+ accurace.

it still dosen't help them in getting there fish to pair up.

although i would DNA test if the reason came about i don't see a huge reason to do it.

Ben
Sat Feb 05, 2005, 11:06 PM
Thanks for the feedback!

How long would the fish be out of water whilst doing an ultra-sound? i guess it would have to be several mintues?

I am not familar with doing a DNA test on faeces?
I think it has to be done to something that grow's eg, skin, hair, eggs etc.
but i am not %100- on testing faeces...

I know that %90 is pretty close to perfect, but i guess i am looking for the %100 method.

I fing it rather interesting that most people are against Dna testing with fish........

kalebjarrod
Sun Feb 06, 2005, 01:43 AM
not against, just can't see a real purpose

it will stress the fish and what can you achive from the results?

flukes
Sun Feb 06, 2005, 03:54 AM
Thats how i would put it, like Ryan did.
Iam not against it but there is no real reason too.
I couldn't see how it would help big time breeders ethier. Some of these fish farms have over 1000 fish could you imagine spending $50,000 just too know they sex of each fish. And its not like its a waste if 2 fish are both female just because they are the same sex doesnt mean they cant sell one of them or both.

If it was cheaper i think it could be good at a higher level were larger sales are being made, but at a hobbyist level even if it was cheaper i couldn't see it becoming a regular thing.

If it was say $10 a fish then sure the discus farms in Penang might do it and yes it probably would increase there sales. Sure id buy a fish if i knew the sex of it but if i dont well then that fine too..

wyldchyld01
Thu Feb 10, 2005, 09:00 AM
prodigydiscus,

DNA testing takes a long long time, even for humans it is a process that takes weeks to complete, so for a fish's DNA sequence to be analysed then (if possible,once the correct genome is identified) to be told if it's a male or female, you'd probably have worked it out yourself.

the idea is great don't get me wrong, but there is no process available today that will tell you in ten mins or so what sex can be produced, some fish do produce a higher number of males at higher temps and vice versa but you can't get the same thing with DNA and as for $50, the test i'd dare say would cost a bit more as the sample needs to be sent off to testing stations not done on site (sent through centrifuges etc)

ultrasound is different, it works by penetrating outer muscle and eroneous material (skin etc) to then identify on feteus any male organs or lack thereof, those that wish to know the sex of their unborn can still be given an incorrect reading if the youngen doesn't feel like showing all (as it were).

if it were possible, maybe in the future with better technology, it would then become a moral issue, do i keep this male or terminate because i want a female and vice versa

a good topic you brought up i must say and ideally i would (and have voted) yes

brenton

Ben
Thu Feb 10, 2005, 10:33 PM
Brenton thanks for your feedback.

Firstly you are right! It would take some time and I am sure some $ to get the fish's DNA sex sequence. But ok, lets say hypothetically that this has already bean analysed and solved and is on file. The next step would be easy! It would take no more than a week to have the sample analysed.

I like your point about it becoming a "moral issue"

Let me quote this out of the dictionary:

A/ of or being the principles of right and wrong in human behaviour

B/expressing or teaching a conception of right behaviour

C/conforming to a standard of right behaviour or to the dictates of one’s conscience.

Due to the advancement of technology and life, does the meaning of MORAL need to be addressed and changed?