In a word......taurine.

"Jo Firey" wrote in message
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: "Jette Goldie" wrote in message
: ...
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: Dogs, on the other hand, can happily survive on catfood - in
: fact one of the local vets suggests feeding elderly and ailing
: dogs on cat food because it is more nourishing for them.
:
: Cat food nearly killed our first dog. She went into kidney failure at
seven. And
: that was just what she stole from the cat. The high protein is hard on
their
: kidneys. This was before we learned to be picky about buying non-grocery
store
: foods. Now we feed Nutro.
:
: However, I never found a better training snack for a dog than a few pieces
of cat
: kibble kept in a pocket.
:
: And cat food might be nourishing for some elderly dogs who are simply not
eating.
: (Mine says she'd rather have steak and lamb) But most senior dog foods
contain more
: cereal (rice) not less than food for younger animals.
:
: Jo
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