[NHCOLL-L:5238] Re: Preserving a dead shark
Dirk Neumann
Dirk.Neumann at zsm.mwn.de
Tue Feb 1 06:15:16 EST 2011
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/
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