vitamin b12 revisted

[Guest guest]

hi all,

stupid me got into a debate with some folks who feed a *vegan* diet to their

cats and dogs. Yes, *vegan* - no joke. If you think vegans in general are

intransigent, try debating with vegans who force herbivory onto their

carnivorous pets

(and then talk about 'cruelty-free' products. what is 'cruelty-free' about a

vegan cat or dog??)

anyway, it's at least spurred me to dig deeper into the b12 issue. i think i

mentioned earlier in the discussion that *true* b12 can only be gotten from

animal sources. someone responded by saying that science now knows how

animals synthesize b12 and they 'make' b12 in the lab using the same

bacteria that animals use to synthesize b12. thus, she said this is

'cruelty-free' b12. she then went on to say how easy it often is to

replicate nutrients in a lab once it's understood how meat animals

synthesize them. (wish i had that much trust in scientists! <g>) finally,

she said her vegan dog gets plenty of b12.

well, that may be so, but i have to wonder how bioavailable supplemental

forms are to canines, and how efficiently any given dog (or cat) can utilize

this non-animal source.

from my readings, i gather that cyanocobalamin is the 'synthetic' form that

is 'created' in the lab here in the US. (There are two commercial forms of

B12: cyanocobalamin crystalline, which is available in the United States,

and hydroxocobalamin crystalline, available in Europe.

http://www.postgradmed.com/issues/2001/07_01/dharmarajan.htm) Does anyone

know of any other forms found in supplements that are not animal-derived?

Also, what happens to the cyanide fraction when the cobalamin is liberated

from it?

Also, i read that...

" In foods, hydroxo-, methyl- and 5'-deoxyadenosyl-cobalamins are the main

cobalamins present. "

http://216.239.37.100/search?q=cache:wWjGyKGrtAYC:europa.eu.int/comm/food/fs

/sc/scf/out80d_en.pdf+animal+derived+b12+cyanocobalamin & hl=en & ie=UTF-8

my main question to the group is: how does supplemental b12 (cyanocobalamin

or hydroxocobalamin) differ from the b12 found in animal flesh (hydroxo-,

methyl- and 5'-deoxyadenosyl-cobalamins)? how does the bioavailability

compare between them? And does the body utilize them in the same way? (i

realize there may be differences in the way dogs, cats and humans utilize

these various forms, but welcome info on any of these species.)

TIA

Suze Fisher

Lapdog Design, Inc.

Web Design & Development

http://members.bellatlantic.net/~vze3shjg/

mailto:s.fisher22@...