I suppose that the best way is the deep freeze

i always use 10 %formaldehyde to analyse a tissue either histologically or biochemically as i feel its a better way to utilise the tissue contents and for vertebrate v tissues u can use BOUINS fixative

Deep freezing hardens the tissues and makes them brittle and u never get good results hence my suggestions is moderate cooling of the tissues

I am not working with genetics, I am thinking that formaldeyde is a little dangerous for the tissus but may be Padmaja knows better since is working with them

My problem is, we don't have much money to buy Tri-reagent/trizol. My doubt is about the carapace. I need to know the best way using alcohol. I will collect and do the analysis over a period of three months. I read some papers (Hsi-Te Shih for example) with Uca and genetics, and they used alcohol!

I fixed with 10% formalin for a few days (3-10 days) after I put in 70% alcohol. I hope this helps.

Ok, I'll talk with Bruno. Maybe he can talk a little more about this metodology.

I thougt too about freezing. Maybe I can freeze the samples, and, when I travel to do my analysis, I'll put them in alcohol.

Hi

I have also worked on molecular biology of freshwater shrimps of family atyidae, 70% Ethanol was found best for my samples...

We are working on lobster shell and tissue, extracting bacterial and eukaryotic DNA, and have found that 96% ethanol at room temperature for a few days (or -20 for longer storage) works fine for subsequent DNA extraction. Qiagen blood & tissue extraction kit works OK with quite good yield. Make sure your samples are broken into as small pieces as possible for storage, and have a large volume of ethanol relative to the sample volume. We have even shipped samples from USA to UK at room temperature (with ethanol decanted off and then replaced upon arrival) - samples seem fine and we get good DNA recovery from these samples. I also received a specimen of hetaopancreas that had been fixed in formaldehyde, then shipped in ethanol. This was also OK (you need to rinse the sample a few times with PBS before extracting DNA if formaldehyde has been used).

Good luck.

Anila and Sylverster:

How long have you stored the samples before do the extraction?

70 % Alcohol would be good way if you want to preserve any specimens for genetic analysis. Otherwise preserving them in cold storage like -20 C will also help you.

90-96 Ethanol at 4 C for a year.

I did this today! Thanks!

Fingers crossed

All depends on what you will give to the sample, you can use Absolute Alcohol 70% or formalin 10% the problem is as I said before the use of samples, if you Formalin body may no longer be used for molecular analysis, but preservation of the specimen only can use 10% formalin which is cheaper.

I'm agree with Sylvester Fredrick, but, if you gonna make molecular analysis you must use 70% alcohol in cold temperature, or 96% alcohol if you are sampling away of your lab. If you want conserve it for long time, but not genetical analysis included, you must introduce Formaldehid 4% into the crab (use injection tools, make it only with big crabs cl> 3 cm), and after reserve in alcohol 70%.

In the histological study, i used the specific fixative (Davidson fixative). The absolute alcohol is good for storage DNA sample.

M y research work about crustacean reproduction and pharmacological endocrinology .that is i always prefer 10% formaladehyde for histological studies and for biochemical work its better to use 70& alcohol always for better results .

Dear reserches,

I've used alcohol 70-92% at 16ºC.

Last week, one of my co-workes did a extration and it's ok (but she used an important kit that I dont know the name).

Hereafter I'll do a sequencing and tell to everybody my results.

Ps: If anybody here know someone who works with fiddler crabs or crab genetics, send me a message.

Thanks for all!

Dear Researches-

The preservation of crustacean of microscopic animal was 2 to 5 % of formalin best preservation, but your species for (Fiddler Crabs - genus Uca) 8 % to 10 % of formalin was very good preservation of the specimen.

As far as shrimp spp. preservation are concern, we are adopting 2% formalin with distilled water, the only problem will be discoloration after 7 to 8 days.

sir ur question is about storage of Uca -fiddler crabs . if u are doing histology u can use 10% formaldehyde to preserve the tissues for 1 day . day after that u dont get good results but if u are working on gene sequences then preserve the live homogenised component in freezer or ice boxes and can work within 2 or 3 days for good results .

Dear Bastos the best way for conservation is the remaining of the crabs in alcohol 95%

Fixation and preservation depend on what you plan to do with them. For molecular studies we use 95% ethanol. We've even used rum (80 proof or 40%) for short term uses to transport from remote sites, but you have to move samples into 95% ethanol thereafter. We've also used frozen samples kept at -20C or -80C. Both ways work.

For histological processing there are many fixatives - Bouin's, Davidsons, 10% neutral buffered formalin, z-fix, normalin, etc. and their use partly depends on your plans. For example, Bouin's solution is not a good fixative for in situ hybridizations using DNA probes, but Z-fix and 10% neutral buffered formalin are good for that application. On the other hand Bouin's gives superlative results for standard histology. Rule of thumb: 10 parts fixative to 1 part tissue. Do not attempt to crowd tissues into too little fixative as the quality of the tissues decreases rapidly with poor fixation. You can refresh the fixative if needed, and for histology, you want to swap out of fixative into 75% ethanol after 2-3 days.

If you're concerned about penetration of your fixative or preservative into your samples, you can "pop the top" on your crabs, inject them with fixative after killing them on ice, or save legs that have dropped from autotomy.

contact , Crustacen culture division, CIBA, Chennai.. its an R&D institute similar work of you is being carried out there

Fiddler crabs are not bigger, and that is an adventage to preserve them in alcohol 70 - 96%.

Some people save them in a cool temperature (4-20°C) to other studies, including alcohol.

Some people use Formaline 4%, or Davidson Solution, but it is coming obsolet because the Formol dangerous consecuences.

Please be careful with the use of formalin/formaldehyde. It is carcinogenic (cancer causing).

Alcohol 96% because is for molecular analysis, Its better and easier to extract DNA for that conditions, we usually keep it at room temp (20-24ºC) and works just fine.

If you can keep them at -20ºC without alcohol nor another thing (just the animals, in a bag or a bottle) do it, its better for DNA extraction ;)

Take care and good luck!