Q: Soybean Oil as the second ingrediant [in Natural Gold]?  I am
   assuming that some of the protein is coming from the Soybean oil
   but is that bioavailable to the ferret?
 
A: I wonder, do you think Soybean Oyl is a relative of Olive and Castor?
Did you know Olive Oyl s mother was named Nana Oyl, a reference to banana
oil?  At the time, banana oil was slang for, well, bullpoop.  Not that
there is any hidden meaning in this attempted joke, except from Max, I
just thought it would be an opening to say I have a ferret named Olive
Oyl.  And Popeye, Bluto, Sweetpea, and Betty Poop.  Oops, oops, de poop,
I meant Boop.  Ack, ack, ack, akc, ack.
 
Well, if it is oil, you are not going to get a lot of protein.  If fact,
there shouldn't be any protein in pure oil, regardless of the source,
animal or plant.  For your edification, the analysis of soybean oil is
as follows: 1 cup = 1927 calories, 218 g fat, 31 g saturated fat, 0 g
cholesterol, 0 g carbohydrate, 0 g protein.  That comes right off the
label on the bottle in my kitchen.  The fat in the Natural Gold diet
comes from a combination of Poultry Fat and Vegetable Oil, (the
ingredient list you mentioned is out of date).  Oils ARE fats; it is
just that they are liquid at room temperature.  Oils generally come from
plants, but are also derived from fish, marine mammals, or processed
animal fats.  There is no truth to the rumor that my hair is an important
source of oil.  Saturated fats are generally solid at room temperature,
monosaturated fats are generally liquid at room temperature and harden
when refrigerated, and polyunsaturated fats remain liquid when
refrigerated.  The terms saturated , monosaturated , and polyunsaturated
are simply a reference to the number of double bonds in the molecule,
impacting physical properties such as being a liquid at room temperature.
A polyunsaturated fat has more than one double bond, a monosaturated fat
has only one double bond, and saturated fats have no double bonds.  No
double bonds means there is more hydrogen attached, thus the molecule
is saturated.  One of the physical properties influenced is the melting
point, which is why some fats are liquid at room temperature, and others
are not.  The double bonds are at the fatty-acid part of the molecule,
and since the fatty acids are built into fat, the type of fat you eat
influences the type of fat you make.  Experienced nurses at plasma
centers can look at the color of blood plasma, which is influenced by
the fat it contains, and tell if you eat a lot of fatty meats.  Eat some
BBQ ribs, peanut-buttered bread, and a milk shake and the your blood
plasma can be the color and opaqueness of French vanilla ice cream, and
is called alimentary lipemia.
 
Fats, solid OR liquid, are essentially chains of glycerols and fatty
acids, and are sometimes referred to as triacylglycerols.  "Triacyl"
means there are three fatty acids per glycerol.  A "glycerol" is a
three-carbon monosaccharide (or sugar), and provides the backbone for
the triacylglycerols, more commonly called triglycerides.  So, what
basically happens is fatty acids are attached to the glycerol, creating
triglyceride, and chains of triglycerides are strung together, creating
fat.  Depending on the amount of hydrogen and the bonds, the fat is solid
or liquid at room temperature.  It is obviously much more complicated
than this, such as other types of fat (phospholipids and cholesterol),
but this is basically how it is done.  Remember this explanation, because
it is important when discussing fat digestion.
 
Fat digestion begins in the stomach when foods are churned, mixed with
stomach fluids, emulsified, and broken down into chyme.  The chyme is
squirted into the duodenum, where it is mixed with bile salts, pancreatic
juices, and intestinal secretions that contain different types of
lipases, which are enzymes that break down fats.  The fats in the chyme
are emulsified by the bile salts, making large fat droplets smaller to
aid in digestion, and the lipases start breaking bonds in the fats,
taking them down to their constituent parts.  Like in humans, ferrets
have a lipase that requires bile salts to work (called bile
salt-dependent lipase), and it is created in the pancreas of adult
ferrets (baby ferrets get their lipase in their mother's milk).  During
digestion, the lipase breaks neutral fats down into diglycerides,
monoglycerides, free fatty acids, and glycerol.  Bile salts then help
corral the cholesterol, free fatty acids, and monoglycerides into little
packets called micelles, which are absorbed by intestinal cells.  Once
absorbed, the broken-down fat is rebuilt into triglycerides, which are
released into the lymphatic system, and ultimately into the blood system.
Some of the fatty acids are not reconstituted into triglycerides, but
instead pass into the blood system with glycerol and can be used for
energy, or converted into other substances as needed.
 
Now, if you read carefully, the importance of different types of fats
does not lie so much in their digestibility, as it does for the fatty
acids it contains (the fat-soluble vitamins are also important, but
in commercial ferret feeds, they are added to the mixture later).
Pancreatic lipase will break apart most fats, regardless of their length.
So, as far as the ability of the ferret to digest a particular fat is
concerned, it really don't matter what fat you give them.  If it came
from a fish or mammal or plant, or if it is an oil or solid fat at room
temperature, the ferret can digest them all.
 
Fatty acids are another matter; ferrets can certainly digest them, but
making them is another matter.  Some fatty acids are called "essential"
because the ferret cannot make them and has to get them in their diet.
These fatty acids are usually found in animal fats, although plant
sources are just as good.  Ferrets need at least three fatty acids,
linoleic acid being the most important because it is the precursor of
the other two.  Besides being in animal fats, linoleic acid is found in
soya, sunflower, and maize oils.  So, when you see soybean oil (= soya
oil) listed in animal foods, you now know the nutritionist is taking
advantage of the 10% linoleic acid contained in the oil to provide the
essential fatty acid to the consuming ferret.
 
By now, assuming you haven't stroked out or fallen from your chair out of
boredom, you will have learned that ferrets can digest fat from either
animal or plant sources, and vegetable fats, such as from soybean, can
be excellent sources of essential fatty acids.  Essential vitamins are
another matter, and will be discussed separately at a later time.
 
Bile salts are important to emulsify fats, but they are created in finite
quantities.  If the ferret consumes more fats than can be emulsified by
the available bile salts, their likelihood of being absorbed is reduced
and they just drop out the tail end of the ferret.  Both excess fats and
bile salts can cause diarrhea.  If the poo smells bad, is frothy looking,
pale, or appears greasy, place a scoop of it in a dish of water.  If it
floats, it is probably steatorrhea and there is too much fat in the poop,
probably from too much fat in the diet or not enough bile salts.
However, if it not just an occasional occurrence, it can also mean your
ferret has metabolic problems, or liver or pancreatic disease, so you
need to see a vet and show them a sample.  Ferrets have rapid food
transit times, roughly four hours from end-to-end.  Because of this, if
bile salts are not absorbed, they can cause diarrhea.  A bright green
liquid poop, for any reason (ECE, rancid food, etc.) usually means you
are looking at a lot of undigested bile.  If your ferret isn't getting
enough fat, excess bile salts may result in loose or squishy poop.  Of
course, diarrhea from any cause can cause dehydration, so make sure your
ferret has enough cool, fresh water at all times.
 
Digestive physiology is adaptive: it will adjust to diet (especially a
monotonous diet, like kibble), putting out appropriate amounts of lipase
and bile salts to fit the average meal.  Changing to a new diet with
higher (or lower) quantities of fat will often cause loose stools.  The
change in bowel habits can originate from a number of reasons, but fat
and bile are two common ones.  It takes a few weeks to a month, but the
digestive system will usually sort things out and readapt to the new
diet.  More questions answered tomorrow.
 
Bob C Communication?  [log in to unmask]
Questions?  [log in to unmask]
[Posted in FML issue 4574]