On 5/16/2010 12:46 PM, sighthounds & siberians wrote:
On Sun, 16 May 2010 02:38:42 -0400, "Paul E. Schoen"
wrote:

"sighthounds& wrote in message
...

But that's not the formula I was using. I was using the feeding rate
for dogs, because I thought we were talking about dogs. You want to
pontificate about different mammals, birds, shrews, whatever, go
ahead; I'm done.

The feeding rate for dogs was given at an "average" weight, and even that
seems rather high. I showed the rates for other mammals to illustrate the
undeniable trends at the far extremes. Among dogs, the actual numbers may
vary widely based on other factors, but it should be obvious that the
average Chihuahua and Mastiff, under similar conditions, would have
statistically significant differences in feeding rate per unit weight.

Raw feeders feed 2-3% of the dog's body weight. That's what Phyrie
feeds Kiba, and that's what my Borzoi pup's breeder feeds her Borzoi.
I have yet to hear that Yorkie owners feed 6% of their dogs' body
weight and Wolfhound owners feed 3%.


"Smaller dogs
often have higher metabolisms, and *may* (not always) need more than the
2% to
3% of their body weight, and often do better with three smaller meals a day,
especially toy breeds."

http://www.b-naturals.com/newsletter/low-glycemic/

"Char" wrote in message
m...
On 5/16/2010 12:46 PM, sighthounds & siberians wrote:
On Sun, 16 May 2010 02:38:42 -0400, "Paul E. Schoen"
wrote:

"sighthounds& wrote in message
...

But that's not the formula I was using. I was using the feeding rate
for dogs, because I thought we were talking about dogs. You want to
pontificate about different mammals, birds, shrews, whatever, go
ahead; I'm done.

The feeding rate for dogs was given at an "average" weight, and even
that
seems rather high. I showed the rates for other mammals to illustrate
the
undeniable trends at the far extremes. Among dogs, the actual numbers
may
vary widely based on other factors, but it should be obvious that the
average Chihuahua and Mastiff, under similar conditions, would have
statistically significant differences in feeding rate per unit weight.

Raw feeders feed 2-3% of the dog's body weight. That's what Phyrie
feeds Kiba, and that's what my Borzoi pup's breeder feeds her Borzoi.
I have yet to hear that Yorkie owners feed 6% of their dogs' body
weight and Wolfhound owners feed 3%.


"Smaller dogs often have higher metabolisms, and *may* (not always) need
more than the 2% to 3% of their body weight, and often do better with
three smaller meals a day, especially toy breeds."

http://www.b-naturals.com/newsletter/low-glycemic/

Yes, as I had stated previously. 2%-3% is a rather wide range, and reflects
the differences in metabolism of dogs of about average weight, about 20 kG.
My estimate for a Chihuahua of 2 kG was 4%, and that might vary from 3% to
5%. And for an 80 kg Mastiff, my estimate was about 3%.

And these estimates are based on dry kibble. Raw food, or even canned, has
higher water content and thus the percentage based on weight would be
higher. But it also depends on the usable caloric content as well as the
amount of protein and other nutrients. So, of course, the amount of a higher
quality food would be less.

The amount of food required based solely on caloric content would be
approximately according to the ratio of surface area to volume. We may
assume the animal is a sphere (the target shape of an extremely obese animal
, and the density to be approximately that of water, or 1 kg/L.

The area of a sphere is pi*D^2, and the volume is pi*D^3/6, and weight is
proportional to volume. For example, a 2 kG spherical Chihuahua has a
diameter of 15.6 cm and a surface area of 767 cm^2. An 80 kG spherical
Mastiff has a diameter of 37 cm and a surface area of 4316 cm^2. The
area/mass for the Chihuahua is 383 and for the Mastiff it is 112. So based
on caloric needs alone, the Chihuahua would need 383/112=3.4 times as much
food as a percentage of body mass, which is based on the cube root of the
mass ratio.

But obviously there are other factors involved which are proportional to
weight (or volume), so this will be lower. If it is split 50/50 for caloric
and nutritional needs, the ratio is about 1.5 So 2-3% for a Mastiff and 3-5%
for a Chihuahua is about right.

Isn't science wonderful? And don't I have entirely too much time on my
hands? Yup and yup

Paul and Muttley
www.muttleydog.com