[NHCOLL-L:5241] Re: Preserving a dead shark
H.J. Walker
hjwalker at ucsd.edu
Tue Feb 1 15:45:29 EST 2011
Agreed; a combination of slitting, and injection into other body areas
of large specimens would be ideal. (But on the deck of a rolling ship,
you just do what you can.) For some students, fishers, and other folks
not familiar with formaldehyde in the field, we recommend freezing.
This allows us to obtain a tissue sample for DNA and to process the fish
in the lab; and for the most part, these thawed specimens (both
cartilaginous and bony fishes) are in excellent condition. One thing
that should NOT be done is try to fix a frozen specimen in formaldehyde,
as was mentioned by someone, for reasons previously discussed.
Best, H.J.
Dirk Neumann wrote:
> Hi Greg,
>
> slitting is preferred especially in (very) large specimens, to allow a
> sufficient influx of preservative fluids. Even though if you inject
> highly concentrated formaldehyde solution (up to 37%), you might have
> problems if the total fluid amount is not sufficient to reach all /
> the rostralmost organs, i.e.the stomach. Furthermore, the preservative
> might be degraded from (fatty) body fluids escaping from the - already
> decomposing - guts.
>
> In many species (especially predators), autolysis of the guts is quite
> fast. This is not that much an issue with frozen specimens, but with
> fresh ones, e.g. cichlids of the genus Crenicichla or the herbivorous
> Steatocranus are notorious for autolysis of their guts within minutes.
>
> Fixation of large herbivorous / detritivorous Cyprinids may cause
> another problem: because of slow fixation rates of the limited amount
> of preservative after injection, the enzymatic processes in the guts
> are not stopped in due time, so that fermentation gases may be an
> issue (blowing up the specimens like a ballon). But this is again more
> a problem when fixing fresh specimens rather then frozen ones.
>
> You may be interested in a recent publication on preservation of fresh
> water fishes in ABCTaxa, which benefited much from the input of Andy
> Bentley and Simon Moore!
> http://www.abctaxa.be/volumes/volume-8-manual-atbi/chapter-22
>
> You may find preservation routines e.g. for the herps, mammals etc. in
> separate chapters of this publication.
> http://www.abctaxa.be/volumes/volume-8-manual-atbi/chapter-22
>
> All the best
> Dirk
>
> Am 28.01.2011 14:36, schrieb Watkins-Colwell, Gregory:
>>
>> I agree with Carol. I formalin-fix a lot of zoo stock and other
>> things (road kills, etc.) that are frozen prior to me prepping them.
>> The problem specimens are always either frozen after decomp started,
>> or from freezers that had electrical issues and thawed a few times.
>> Freezer burn is also a huge issue, especially if the specimen was
>> stored in a frost-free freezer. I’ve had some luck with donors
>> freezing the specimen in a block of ice. This at least reduces some
>> of the freeze-dry effect.
>>
>>
>>
>> As for injection vs. slitting... does anybody know why slitting is
>> more common in fish prep than injection? I have always assumed it’s
>> because it is faster on a RV to just slit the fish and toss them into
>> a vat of formalin than it is to stop and inject them individually.
>> But is there any benefit to slitting vs. injection? I’ve done both
>> and personally like the results of injection better. I feel like I
>> have more control over where the juice goes. But maybe I’m missing
>> something.
>>
>>
>>
>> Greg
>>
>>
>>
>>
>>
>> --------------------------------------
>>
>> Gregory J. Watkins-Colwell
>>
>> Division of Vertebrate Zoology
>>
>> Yale Peabody Museum of Natural History
>>
>> 170 Whitney Avenue, Box 208118
>>
>> New Haven, CT 06520
>>
>> 203/432-3791 or fax: 203/432-2874
>>
>> -----------------------------------
>>
>> *From:* owner-nhcoll-l at lists.yale.edu
>> [mailto:owner-nhcoll-l at lists.yale.edu] *On Behalf Of *Carol Spencer
>> *Sent:* Thursday, January 27, 2011 7:27 PM
>> *To:* rrosenblatt at ucsd.edu
>> *Cc:* NHCOLL-L at lists.yale.edu
>> *Subject:* [NHCOLL-L:5219] Re: Preserving a dead shark
>>
>>
>>
>> Hi all,
>> I prepare many specimens from frozen animals for herps often (from
>> specimens that people have donated to us). We thaw them completely in
>> a cold room, then take tissues samples, and THEN prepare in formalin.
>> You cannot take tissue samples after the specimens has been fixed in
>> formalin. I have never had a problem with specimens being rotten or
>> disintegrating before they thaw completely. A bigger issue is the
>> specimens not turning out as nice as a fresh specimens because of
>> freezer burn, so for this reason it's best to get it out of the
>> freezer and prepared as soon as possible.
>>
>> -Carol
>>
>> On Thu, Jan 27, 2011 at 2:36 PM, Richard Rosenblatt
>> <rrosenblatt at ucsd.edu <mailto:rrosenblatt at ucsd.edu>> wrote:
>>
>> I second (or third) the recommendations of Dirk and John. It should
>> be totally unnecessary to inject a small shark. If you thaw it in
>> formalin the outer tissues will become fixed as it thaws and prevent
>> further diffusion. One refinement would be to put the specimen in
>> formalin for 30 minutes or so to let the skin harden before
>> slitting-keeps the body wall from gaping. All the chemistry as
>> recommended is simply not needed.
>>
>>
>>
>>
>> DIrk and SImon
>> My concern with thawing the shark prior to preservation is the amount
>> of tissue damage that occurs during freezing and thawing which is why
>> I reccomend thawing in fomaldehyde. Your comments on this will be
>> appreciated.
>> John
>>
>> ----------
>> Sent from the Verizon network using Mobile Email
>>
>> ------Original Message------
>>
>> From: Dirk Neumann <Dirk.Neumann at zsm.mwn.de
>> <mailto:Dirk.Neumann at zsm.mwn.de>>
>>
>> To: <Couteaufin at aol.com
>> <mailto:Couteaufin at aol.com>>,<sej139 at yahoo.com <mailto:sej139 at yahoo.com>>
>> Cc: <NHCOLL-L at lists.yale.edu <mailto:NHCOLL-L at lists.yale.edu>>
>> Date: Thu, Jan 27, 8:43 AM +0100
>> Subject: [NHCOLL-L:5211] Re: Preserving a dead shark
>>
>> Hi Steven, Simon,
>>
>> from experiences with preservation of our 200 something Etmopterid
>> sharks I would adjust Simon's procedure as follows:
>>
>> Thaw the shark under cold water (don't use hot water)
>> Pin the fins prior to formalin fixation and try to get the shark in a
>> somehow natural shape (elsewise you will fix the specimen as bended as
>> retrieved from the freezer).
>> Take the tissue sample in advance (immediately after thawing), best take
>> muscular tissue from inside of the body cavity by cutting the abdomen IN
>> FRONT of the anus
>> Cut the body cavity to allow influx of formaldehyde solution into the
>> belly; this works much better then injections and especially allows
>> escape of the oil emerging from the liver which elsewise you will have
>> an awful smelly preservation issue for years (see Simon Moore's comments
>> on this, you may have a pH-issue with breaking fatty acids).
>> Consider to wash the specimen with a bit detergent after recovery from
>> fixation to avoid too much oil in the alcohol.
>> Sharks are rather easy to preserve and not as sensitive as most bony
>> fishes.
>>
>> Hope this helps
>>
>> All the best
>> Dirk
>>
>>
>> Am 27.01.2011 00:22, schrieb Couteaufin at aol.com
>> <mailto:Couteaufin at aol.com>:
>>
>> Hi Steven,
>> You shark - what you proposed re the formalin sounds fine to me. Once
>> fully thawed, inject it with 10% formalin (3.76% formaldehyde) until
>> it just starts to swell ever-so slightly or the fluid runs out
>> again. Make sure that you inject the brain area, the area round the
>> liver and
>> the pelvic cavity too.
>> You can then preserve it (after a few days) in 5% formalin, alcohol
>> (gradually up a ladder of 20% stages) or whatever preservative seems
>> easiest. If you want DNA then don't leave it in formalin for more
>> than 5 days and transfer to alcohol. You will get some lipid (as
>> yellow-brown globules) leaching in time from the liver in particular,
>> as formalin will only preserve lipid. Don't worry if the fluid is
>> still clear but if it turns at all murky or dark brown, check the pH
>> and change the fluid anyway for fresh.
>> Have fun and check out the website below, if time permits.!
>> With all good wishes, Simon
>>
>> Simon Moore MIScT, FLS, ACR,
>> Conservator of Natural Sciences,
>> 20 Newbury Street,
>> Whitchurch RG28 7DN.
>> www.natural-history-conservation.com
>> <http://www.natural-history-conservation.com>
>> <http://www.natural-history-conservation.com/>
>>
>> http://uk.linkedin.com/in/naturalsciencespecimenconserve
>> In a message dated 26/01/2011 22:41:20 GMT Standard Time,
>> sej139 at yahoo.com <mailto:sej139 at yahoo.com> writes:
>>
>> Hi everyone, sorry to bother the list with something that isn't
>> really all that
>> paleo related, but I was wondering if someone could help me out. I
>> recently got
>> a roughly 1 foot long baby shark. Since it is so young, I would
>> like to preserve
>>
>>
>>
>> it. It is currently frozen in a block of ice until I can figure
>> out what to do
>> with it. Since I would like to preserve it, I was wondering what
>> the best and/or
>>
>>
>>
>> easiest way to do that might be. I have been leaning toward
>>
>> > getting some
>>
>> formaldehyde or formalin, injecting some into it and preserving it
>> in a jar with
>>
>>
>>
>> the rest. If that is best, how much should I inject into it.
>>
>> Thanks for any help I receive,
>> ~Steven
>>
>> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>> Steven E. Jasinski
>> Paleontological and Research Assistant
>> State Museum of Pennsylvania
>>
>>
>> Graduate Studies
>> Department of Biology
>> East Tennessee State University
>>
>>
>> Phone: (717)586-9835
>>
>>
>>
>>
>>
>>
>> --
>> Dirk Neumann
>>
>> Tel: 089 / 8107-111
>> Fax: 089 / 8107-300
>> email: Dirk.Neumann(a)zsm.mwn.de <http://zsm.mwn.de>
>>
>> Postanschrift:
>>
>> Staatliche Naturwissenschaftliche Sammlungen Bayerns
>> Zoologische Staatssammlung München
>> Dirk Neumann, Sektion Ichthyologie / DNA-Labor
>> Münchhausenstr. 21
>> 81247 München
>>
>> Besuchen Sie unsere Sammlung:
>> http://www.zsm.mwn.de/ich/
>>
>> ---------
>>
>> Dirk Neumann
>>
>> Tel: +49-89-8107-111
>> Fax: +49-89-8107-300
>> email: Dirk.Neumann(a)zsm.mwn.de <http://zsm.mwn.de>
>>
>> postal address:
>>
>> Bavarian Natural History Collections
>> The Bavarian State Collection of Zoology
>> Dirk Neumann, Section Ichthyology / DNA-Lab
>> Muenchhausenstr. 21
>> 81247 Munich (Germany)
>>
>> Visit our section at:
>> http://www.zsm.mwn.de/ich/
>>
>>
>>
>>
>>
>>
>> --
>> Carol L. Spencer, Ph.D.
>> Staff Curator of Herpetology & Researcher
>> Museum of Vertebrate Zoology
>> 3101 Valley Life Sciences Building
>> University of California, Berkeley, CA, USA 94720-3160
>> atrox10 at gmail.com <mailto:atrox10 at gmail.com>
>> atrox at berkeley.edu <mailto:atrox at berkeley.edu>
>> TEL: 510-643-5778 /FAX: 510-643-8238
>>
>> http://www.herpnet.org
>> http://mvz.berkeley.edu/
>> http://www.vertnet.org
>>
>
>
> --
> Dirk Neumann
>
> Tel: 089 / 8107-111
> Fax: 089 / 8107-300
> email: Dirk.Neumann(a)zsm.mwn.de
>
> Postanschrift:
>
> Staatliche Naturwissenschaftliche Sammlungen Bayerns
> Zoologische Staatssammlung München
> Dirk Neumann, Sektion Ichthyologie / DNA-Labor
> Münchhausenstr. 21
> 81247 München
>
> Besuchen Sie unsere Sammlung:
> http://www.zsm.mwn.de/ich/
>
> ---------
>
> Dirk Neumann
>
> Tel: +49-89-8107-111
> Fax: +49-89-8107-300
> email: Dirk.Neumann(a)zsm.mwn.de
>
> postal address:
>
> Bavarian Natural History Collections
> The Bavarian State Collection of Zoology
> Dirk Neumann, Section Ichthyology / DNA-Lab
> Muenchhausenstr. 21
> 81247 Munich (Germany)
>
> Visit our section at:
> http://www.zsm.mwn.de/ich/
>
--
H.J. Walker, Jr.
Scripps Institution of Oceanography
University of California, San Diego 0208
La Jolla, CA 92093-0208
USA
hjwalker at ucsd.edu
phone:858-534-2199 fax:858-534-5306
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