Dear Fernando,

	There is no problem.  My understanding of bird bones is that they tend to
be rather porous, so infiltration of the formalin should not be a problem.
I am assuming that after cutting blocks/sections you continue fixation.
Select your bone sample for EM after fixation in formalin and cutting,
transfer to either glutaraldehyde of a prarformaldehyde/glutaraldehyde mix
in an appropriate buffer for another few hours (assuming a block size of
1x1x1 mm), treat as per a normal EM specimen.  Depending on how you want to
orientate your specimen it can be helpful to cut your bone to a 1x1x2 mm
block.  Choose a harder mix of resin than you would for soft tissue EM
specimens to reduce your sectioning problems.  

	Hope this helps.

	Regards
	
	Rob W.

At 03:16 PM 6/6/99 +0100, you wrote:
>At the time that I prepare the bones (ostrich bones) to light microscopy, I
>have no possibility cut them in small pieces to electronic microscopy. I
>put them in formalin to light microscopy and latter (some hours aprox. 1-2
>hours, because I have an special saw in my laboratory) I saw them in
>another laboratory with that saw. Someone can help me with this: after 1-2
>hours in formalin I have no more possibility to prepare the bones to
>electronic microscopy? 



R. Wadley, B.App.Sc, M.L.S
Laboratory Manager
Cellular Analysis Facility
School of Microbiology & Immunology
UNSW, New South Wales, Australia, 2052
Ph (BH) 	+61 (2) 9385 3517
Ph (AH)	+61 (2) 9555 1239
Fax 	+61 (2) 9385 1591
E-mail	r.wadley@unsw.edu.au
www	http://www.unsw.edu.au/clients/microbiology/CAF.html
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