Date: 2001-03-17 13:25:00 UTC
Subject: Re: [Ferret-Health-list] RE: more on corn
Looks like I caused some confusion about corn/plant
proteins, and urinary ph. Corn and plant based protein
contains amino acids that the ferret can use, but the problem
with corn and most plant based protein is simple. When the
protein is metabolized it will make the urinary ph alkaline.
When the protein from meat based protein is metabolized
it will make the urinary ph acidic. When the urinary ph is alkaline
(i.e., plant based protein) struvite crystals form and urinary
(crystals, infections, bladder stones, blockages, etc) happen.
Why does this happen? Corn and most cereal grains have low levels of
the essential amino acid methionine. Meat based protein has a lot of
methionine. When the essential amino acid methionine
is metabolized it produces a sulfate (SO4-2) that is excreted in
the urine as sulfuric acid (H2SO4), which acidifies the urine!
The good news is most cat and ferret foods have dl-methionine
as an ingredient. This is added to acidify the urine. That is why
we do not commonly see urinary problems in ferrets.
Thus corn as a carbohydrate source will not cause urinary problems.
Jerry Murray, DVM