>So that is what I told the vet tech they are eating.  I was told it
>is not good to mix so many foods.  This stuck me as kind of odd, I
>really didn't see and issue with it.  But, maybe there was a reason
 
I think your vet tech is extrapolating here - and poorly at that.
If you're concerned about it, ask your vet, not the tech, and do
the smart thing - ask for references to the studies that prove or
at least suggest this!
 
Your reasoning is sound.  If each kibble is nutritionally balanced,
mixing different kinds is not going to give you an imbalance.  The mix
will have a different nutrient balance than any kibble alone, for sure,
but not an imbalance.  You're averaging out the nutritional differences,
not creating extremes.
 
I suspect that the tech is thinking of a different problem.  It's known
that if you switch foods it *can* cause stomach upset for a short time.
But what you are doing is not switching foods - as long as the mix
becomes their long-term diet, there is no switching of foods involved.
Once they have adjusted to the mix, they will eat it without problems.
It's not as if each bite causes a food switch.
 
Bob Church recommended feeding this way several years ago - if you must
feed kibble.  You can find this in the archives under his older nutrition
series.
 
This is the way we feed here, with absolutely no problems.  I feed an
equal mix of Totally Ferret, Superior Choice, Superior Choice Natural,
Zupreem, Mazuri, and Path Valley.  When I get food in, I measure each
one into 1 lb Ziploc bags and into the freezer it goes.  When I need
more food, I pull out a bag of each and mix them up.  (I find this
easier than trying to blend a huge 25+ lb batch of kibble at once.)
 
For what it's worth, Zupreem seems to be a good food but I'm phasing it
out because it seems to cause dark stools.  That's not really a problem,
but they look disturbingly like stools from a ferret with ulcers, so it's
a little harder to tell when things aren't right.  The Mazuri is in the
mix only because we took in a shelter ferret who was eating it, and I
ended up getting the 25lb bag.  8-in-1 Ultimate is another good choice
and has been in our mix before.  Marshall's can KEEP their food.  We only
ever use that junk long enough to get newcomers to switch over to the
mix.
 
Note that I can play with the mix a little bit and the ferrets never go
off their food!  This way you're fairly immune to formula changes in
the food or to a food going off the market - as happened briefly when
Sheppard & Greene got bought out not long ago.
 
roger & the fuzzies
missing bear
[Posted in FML issue 3988]