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CRUDE
FIBER VS. DIETARY FIBER
&
FEEDING
THE GESTATING AND LACTATING DOG
FOOD SUPLEMENTS
Mineral Supplements
We will take a quick look at the commonly supplemented minerals. Be
aware, before you read any further, that mineral supplementation of
commercial dog foods is generally ill advised, unless there is some
underlying medical condition.
Unfortunately, many dog fanciers supplement with
calcium. We hear, almost daily, that calcium supplementation in
humans is necessary as they age to prevent osteoporosis,
especially in women. We won't even go there--we are talking
dogs. Every dog food made has adequate calcium content.
There is no shortage of very inexpensive calcium available to the
manufacturers to put in their formulations. It is preposterous to
think that this would be an area in which supplementation is
warranted. In fact, high calcium intake is implicated in skeletal
disease. Yet, it remains common practice for breeders to
encourage puppy buyers to supplement commercial diets with
calcium. What you get are not strong puppies but increased
rates of osteochondritis dissecans (OCD) , enlarged joints,
dropped hocks, splayed feet, angular limb deformities,
wobbler's syndrome and stunted growth. , , Furthermore, high
levels of calcium in the diet have long been known to cause a
relative zinc deficiency in dogs. , While on the topic of zinc
deficiency, we note also that high levels of iron and copper also
interfere with zinc absorption. , If you are to take anything away
from this article, let it be to do no harm with supplements.
Calcium is a very dangerous supplement; one you should not
use except under the careful and participative guidance of your
veterinarian. Even then, it would be worthwhile to check the
nutritional credentials of your veterinarian. Not all veterinarians
are created equal, and few vet schools teach nutrition in any
significant amount. As an aside, dolomite is still available in
health food stores as a supplemental source of calcium. The
joke is on the uniformed buyer: dolomite is rock, relatively
insoluble and certainly not soluble in the gut during the time
normal for passage. However, it does make a wonderful acid
buffering substrate in marine aquaria. Calcium anyone?
The calcium:phosphorus ratio of 1:1.2 or
thereabouts is sacred. Don't even think about messing about
with supplementary phosphorus, regardless of the claims that it
is necessary and without it you run the risks of rickets,
osteomalacia and even nutritionally induced
hyperparathyroidism. Over-supplementation of phosphorus can
remove calcium from bones. Phosphorus is found in meat,
poultry and fish, the very ingredients found in almost all dog
foods. You can buy it off the shelf, but we suggest you leave it
there.
Go ahead and pump magnesium into your dog.
Digestive and internal mechanisms regulate the level of
absorption and generally, no harm will be done. Given that
magnesium is found in soy, corn, other cereal grains and bone
meals, the very staples of commercial dog food, there will be no
shortage. On the other hand, magnesium figures prominently in
shelf space in healthfood stores, and if you own stock in a
company that packages magnesium for such a market, you
might want to buy some for your dog. Otherwise, forget
it--"Poocharelli" already is getting more magnesium than he can
utilize.
no deficiencies are reported in the dog. Don't bother
supplementing unless you have an excess of cash and near cash
assets and your dog will tolerate the taste.
Certainly there can be iron deficiencies that result in
various anemias, but they are not likely with commercial diets,
and not even likely with homebrew diets. How do you get iron
out of meat meals, bone, poultry and dairy products before you
feed your dog? The answer is that you don't. Therefore, absent
a special medical condition, iron supplementation is not
warranted. Leave iron supplements on the shelf at your
healthfood store.
Great in bracelets worn for decorations (but not for
therapeutic value) and great for remembrances of Vietnam
POW's, but poor as a dietary supplement. Copper is found in
organ meats, which are common ingredients in commercial dog
food. It is doubtfulthat you will ever have a valid reason to
supplement with copper.
Unless your dog has a zinc responsive dermatosis, don't
even think about supplementing with zinc. An excess of zinc
causes calcium and copper deficiencies. Given that beef liver,
dark poultry meat, milk, egg yolks and legumes in general are
sources for zinc, no commercial food will ever be short of
zinc--too cheap, too abundant, and you can't get rid of it easily.
Found in meat, poultry and fish, it is unlikely that
either a dietary excess or deficiency will exist in the dog fed a
commercial diet.
Found in beef, liver and fish, it is unlikely that either a
dietary excess or deficiency will exist in the dog fed a
commercial diet.
Found in grains, meat and poultry, it is unlikely that
either a dietary excess or deficiency will exist in the dog fed a
commercial diet. Selenium is paradoxical in that the symptoms
for excess and deficiency are the same. Considered a
micromineral, itoccupies the active site of the enzyme
glutathione peroxidase. This enzyme protects the body from
free radicals formed during oxidation of cell-membrane lipids.
Selenium has a synergistic relationship with Vitamin E. Vitamin
E keeps selenium at its most efficacious oxidation state and
selenium 'spares' Vitamin E.
Found in fish and dairy products, it is unlikely that
dietary excess or deficiency will be noted in dogs fed
commercial diets.
Vitamin Supplements
Not only can you get in trouble with mineral supplements; vitamin
supplements can be dangerous also. Vitamins are required by the dog
in minute amounts to function as enzymes, enzyme precursors or
co-enzymes in many of the dog's metabolic processes. Vitamins fall
into two general categories: water soluble (B-complex, C) and
fat-soluble (A,D,E,K). It is the fat-soluble vitamins that are dangerous
in excess, especially vitamins A and D.
The origin of all vitamin A is the carotenoids in
plants such as carrots, sweet potatoes, deep green vegetables.
Several carotenoids provide vitamin A; however, beta-carotene
is the most common in foods. Note that dogs can convert
carotenoids to active vitamin A, and therefore do not require
animal sources of vitamin A in their diets. Vitamin A is seldom
found as a supplement because its components (retinol, retinal
and retinoic acid), are found in fish liver oils, milk, liver and egg
yolk. Excesses cause skeletal abnormalities and hyperesthesia.
A protovitamin D, vitamin D3 is of importance to
omnivores and carnivores. Active vitamin D is synthesized by
the dog's body thus generating a small controversy over
whether vitamin D should be classified as a hormone or as a
vitamin. Exposure of the dog to sunlight results in conversion of
the precursor 7-dehydrocholesterol to cholecalciferol. Most
foodstuffs contain very little vitamin D, however fish liver oils,
egg yolks and liver are good sources. "Most commercially
prepared pet foodsare enriched with vitamin D to ensure that
dogs and cats receive adequate amounts of this vitamin
regardless of the amount of daily sunlight they receive."
Vitamin E, the biological, chain-breaking
anti-oxidant not only neutralizes free-radicals, but prevents the
peroxidation of lipids within cellular membranes. Vitamin E and
selenium are synergistic. Optimum levels for the dog are still
being researched. Vitamin E is one vitamin with serious research
behind it to support its use as a supplement. It has been shown
to ameliorate the pain of osteoarthritis and recent research now
shows thatit has an analgesic effect in the treatment of
rheumatoid arthritis as well. Its mode of action is the same as
many NSAID's in that it inhibits the enzyme cyclooxinase and
prevents the formation of inflammatory products. The form of
Vitamin E is also important in terms of its efficacy. All natural
(RRR) Vitamin E is 50 % more bioavailable than the synthetic
form.
This vitamin is necessary for blood coagulation can
is commonly given to dogs as an antidote for anti-coagulant rat
poisons. Dogs produce their own vitamin K through bacterial
synthesis in the intestine. Supplementation is not required.
Water Soluble Vitamins
All that needs to be said about water-soluble
B-complex vitamins as they pertain to canine nutrition is that the
B-complex series of vitamins are seldom deficient in dogs. It is
possible to create a thiamin deficiency by feeding a diet of raw
fish, or a biotin deficiency by feeding large amounts of raw egg
whites. As the protein levels in the diet increase, the
requirements for vitamin B6, pyridoxine, increase, however a
diet so concentrated in protein would be most unusual.
The use of an exogenous source Vitamin C is controversial because
the dog is one of several mammals which has the ability to manufacture
ascorbic acid. (Though the dog makes the least amount of ascorbic
acid per kilogram of body weight of any animal who has that ability.)
There is a definite lack of peer reviewed citations with respect to its
use in dogs. However, one study mentioned in the Waltham book on
nutrition does show that blood plasma levels of vitamin C are
dramatically reduced in dogs exposed to oxidative stress. Oxidative
stress can include exposure to toxins, which involve pesticides and
cigarette smoke, and exercise. Performance dogs would be especially
benefit from supplementation. Clinical trials do support its use for
amelioration of pain, but the efficacy seems to depend on the form in
which this vitamin is taken. Calcium ascorbate has a neutral pH so
digestive upsets are avoided and it appears not to be flushed out of the
body as rapidly.
Nutritional Supplements
Extracted from the stem of the pineapple, this
product contains at least eight different protein-digesting
enzymes. Besides its ability to aid digestion, Bromelain appears
to inhibit the synthesis of the E2 prostaglandins
(pro-inflammatory) as seen in arthritic conditions. Clinical trials
have shown it to be effective in reducing swelling and pain due
to injury as well as enhanced healing after surgery. , Recent
studies have assessed its ability to reduce the size of malignant
tumors and it has also been evaluated for its antihelmetic activity
against roundworms. Current use of bromelain is for
preventative nutrition for the geriatric dog and in glandular
therapy.
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Garlic (Allium sativum liliaceae)
Garlic is common in most
kitchens as a flavor enhancer. It figures prominently in both
western and eastern herbal medicine and is making its way into
the mainstream of western medicine. In Europe, garlic is
approved for cardiovascular conditions in humans with high
cholesterol and triglyceride levels. It contains a wide array of
sulfur-containing compounds (over 100) that have potential
health enhancing benefits. Garlic oil contains allicin; this is
subsequently converted by the digestive enzyme allinase to
allicin. This compound, like so many others which contain sulfur,
is thought have many antibiotic, immune enhancing and
anti-cancer properties due to their antioxidant capabilities. As a
natural antibiotic, garlic is remarkably potent, so potent, in fact
that one milligram of allicin is equal in effectiveness to 15
standard units of penicillin against a fairly wide range of
bacteria. Garlic also prevents platelet adhesion and has a
therapeutic effect on serum cholesterol levels and blood
pressure and helps to maintain aortic elasticity. Garlic and ginger
may have synergistic effects, and a combination of garlic and
ginger has been shown to be effective in reducing blood glucose
and serum lipids.
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Ginger (Zingiber officinale Rose)
The health benefits of ginger
seem to stem from its antioxidant ability. However, it is best
known for its ability to aid digestion. It is thought tostimulate
digestion by improving intestinal muscle tone, initiating bile
secretion and soothing nausea. It also contains several
proteolytic (digestive) enzymes. Ginger snaps or cystalized
ginger, given a half hour before a car ride, will often
preventmotion sickness in dogs. Ginger is common in Oriental
medicine and is found in a significant number of the standardized
polyherbal preparations.
(Panax ginseng C.A. Meyer(Korean ginsing); Panax
quinquefolius L(American ginseng).; Panax schinseng Nees) -
With fewer than a dozen species, the genus Panax is not well
understood, there exists white and red varieties with the former
considered to have a higher antioxidant activity. Among the
active ingredients are several central nervous system stimulating
compounds and at least one that has a sedating effect. Ginseng
is probably the most heavily researched herb in the world and
numerous dog studies exist. Certainly, ginseng is one of the
most popular herbs of the Chinese, Korean, Russian and
Japanese medicinal traditions. In addition to it's antioxidant
properties, it is thought to spare glucose during exercise by
promoting fatty acids as a favored fuel source. Ginseng is
classified as an adaptogen as it not only supports adrenal
function, assists in maintaining normal blood sugar and
cholesterol levels, but also increases overall resistance to stress
and disease. Along with Vitamin E, ginseng appears to
counteract hepatic toxins and boosts the immune system by
promoting increased levels of helper T and natural killer cells.
Animal experiments have demonstrated that ginseng is an
immunostimulant. , Ginseng also stimulates protein synthesis in
the liver, which effects that organs ability to regenerate itself and
can increase red blood cell mitosis in the bone marrow.
Paradoxically, even thought the active compounds of this herb
have a very low absorptivity, ginseng seems to alter the
permeability of the intestinal mucosa (lining which contains
mucous secreting glands) and enhances drug and nutrient
absorption.
(Silybum marianum (L.) Gaertn) - Also known as
St.Mary thistle, lady's thistle and holy thistle this plant is best
known for its liver protective effects. The most active ingredient,
silymarin, appears to block uptake of toxins by the liver and
seems to be able to neutralize some toxins that have already
been absorbed. It is thought to stimulate new liver cell
production by promoting protein synthesis. Milk thistle acts like
an antioxidant and is a free radicalscavenger and several
researchers have found it many times more potent an
antioxidant than Vitamin E. It promotes the immune system, but
also inhibits the anti-inflammatory response by stabilizing the cell
membrane, much like Vitamin E. The two, Vitamin E and milk
thistle, taken together seem to have a synergistic effect.
(Ginko biloba L.) - This herb has been used medicinally
for nearly 5,000 years, but only recently has emerged in Europe
as a billion dollar phytomedicinal. Recent research has focused
on its anti-inflammatory properties, especially with regard to
macular degeneration of the eye. It is especially effective against
degenerative neurological disorders that occur with age, i.e.,
Alzheimer's disease and is thus becoming an important herbal
medicine for geriatric patients. Ginko prevents platelet
aggregation and appears to improve circulation in the brain and
extremities. Humans who use this herb relate that it improves
their memory and their ability to concentrate.
(Vaccinium macrocarpon) - A native plant of North
America with no known toxicities. The fruit contains a variety of
organic acids, some of which have antioxidant properties. Often
suggested for use in prevention and treatment of lower urinary
tract infections, it was thought towork because it acidified the
urine; subsequent research has shown its mode of action is to
prevent adhesion of bacteria, such as Escherichia coli, to the
mucosal surfaces of the urinary tract. Blueberries appear to
exhibit similar effects.
(Rosmarinus officinalis) - Rosemary, best known as
a spice and flavor enhancer, is also an antioxidant. Along with
sage, rosemary has the has the highest antioxidant activity of any
of the spices. The most active ingredient is a phenolic
compound called carnosic acid. Like Vitamin C and selenium, it
has the ability to 'recycle' Vitamin E, thus extending that
vitamin's activity. Components of rosemary extract have the
potential to protect mouse liver and stomach from carcinogenic
or toxic agents, and may also have that property in dogs. A
great deal of research is being done with rosemary extract as a
lifelong supplement for the avoidance of various cancers.
(Calendula officinalis L.) - The marigold
flower contains a carotenoid (a plant pigment) with no Vitamin
A activity but appears to have excellent antioxidant possibilities.
A great deal of research attention has been focused on this
compound, as it appears to ameliorate age related macular
degeneration of the eye. The same plant pigment is found in the
green leafy vegetables like spinach. Marigold extract has been
approved in Europe for treatment of slow-healing wounds, and
the extract is also thought to prevent certain cancers.
Although most commonly known for
its ability to ameliorate fecal aroma in both dogs and cats, the
yucca plant appears to have a variety of health benefits. This
plant has a long history of safe food use by Native Americans in
the southwest United States and also in Mexico. Like ginseng, it
seems that yucca maybe improve permeability of intestinal
mucosal cells to improve nutrient absorption, but is itself poorly
absorbed. The active ingredients are a variety of saponins (plant
surfactants) that may act as a prebiotic in the colon where they
are fermented by beneficial bacteria. These plant fibers may
effect cholesterol levels by stimulating bile acid excretion and
human studies indicate that both tryclyceride levels and blood
pressure is lowered by its use.
The grape seed proanthocyanidins (GSP)
are natural antioxidants with a wide spectrum of
pharmacological activity and which also protect cell membranes
from attack by free radicals. Free radicals are highly reactive
molecules in the body which can destroy tissues by oxidizing
cell membrane lipids and damaging DNA, the body's genetic
material. Current research is looking at its ability to inhibit tumor
cell growth and inhibit replication enzymes of HIV viruses. Not
only does it inhibit tumor growth, but it seems to ameliorate the
effects of chemotherapy and exposure to cigarette smoke as
well.
Glucosamine is a constituent of cartilage and
appears to both stimulate the synthesis of proteoglycans and
inhibits their degredation. Proteoglycans are a high molecular
weight complex of protein and polymers of sugar which are a
component of structural tissues of vertebrates. Oral
supplementation appears to improvebone and joint health. ,
This compound is a coordination
complex (a metal ion surrounded by several organic molecules)
that seems to mimic the configuration of a naturally-occurring
substance called Glucose Tolerance Factor (GTF). , Although
first characterized in 1929, the significance of this molecule was
initially overlooked until Dr. Walter Mertz 'rediscovered' it in
the 1960's when he isolated a niacin-bound chromium complex
from yeast extracts. GTE facilitates the attachment of insulin to
its receptor sites. The binding of insulinthen leads to the
increased uptake of glucose (blood sugar). In other words, this
molecule regulates blood sugar levels. This supplement is
especially useful for diabetics but is very effective in overcoming
a condition called insulin resistance which is often present in
obese mammals. Insulin resistance causes hyperinsulinemia
which can increase the risk of heart disease and predisposes
one to diabetes mellitus. This why obesity is such a significant
factor for the onset of this disease.
Obtained from the fruit rind of the Indian
Garcinia cambogia tree, this compound has been used for
centuries by the people of South Asia as a flavor enhancer,
food preservative and to suppress the appetite. It is sometimes
used as a purgative in the treatment of intestinal worms and
other parasites, for tumors, for dysentery and for other digestive
upsets. Much of the modern research about its anti-obesity
effects were undertaken by a pharmaceutical company in an
attempt to create a class of patentable synthetic anorectics. It is
not a CNS stimulant. Instead, its mode of action is to inhibit the
activity of an enzyme called ATP-citrate lyase. Without this
enzyme, fatty acid cholesterol synthesis is blocked
becausecertain key components cannot be transported through
the cell membrane. Thus, excess calories are directed away
from fat production and towards glycogen (another form of
glucose stored in the liver) production and storage. This in turn
produces a feeling of fullness and satiation. Eating less will help
prevent obesity if the dog has a normal metabolism.
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Omega-3 and Omega-6 Fatty Acids
Commercial dog foods
contain polyunsaturated fats with both omega-3 and omega-6
fatty acids. Sources of omega-6 are: linoleic acid from corn,
safflower, sunflower, cottonseed and soy oils. Sources of
omega-3 are: alpha-linolenic acid from cold waterfish oils,
whole fat flax. The use of omega-3 enriched dietary products
has become popular in the treatment of inflammatory skin
disorders. Dogs cannot convert one type of fatty acid to
another, so it is essential that certain omega-3 and omega-6
fatty acids are available in the diet as they are essential for
maintaining normal skin structure and function. The optimal ratio
of omega-6 to omega-3 is between 5:1 and 10:1.
"Supplementing a dog's regular diet with omega-3 fatty acids
may not be effective in decreasing inflammatory potential
because the exact quantities and ratio of fatty acids in the dog's
regular diet are usually not known. As a result it is very difficult
to achieve an effective fatty acid profile through
supplementation." Numerous studies suggest that the
omega-6:omega-3 ratio is more important that the quantity of
essential fatty acids once basic nutritional requirements have
been met. Let us stress again that it is the RATIO of these two
fatty acids that is the mostimportant component. The proper
ratio diverts the production of inflammatory prostaglandins to
the anti-inlammatory products. If you are having problems with
your dog's skin condition, you would be better advised to try
one of the veterinary diets with a controlled omega-6:omega-3
ratio than attempting to adjust the ratio through supplements.
Co-enzyme Q 10 - To be accurate this product cannot be
considered a food supplement. Instead you must regard it a
component of the dog's energy transduction system (conversion
of food into energy storage). When the body breaks down
food, it stores the inherent chemicalenergy in a high energy
chemical bond. It does this by passing electrons down a chain
of proteins that are stored in the membrane of tiny cells called
mitochondria. During aging, the dog's ability to maintain this
process slows down but we are able to preserve this process
by supplementation with co-enzyme Q10. It is also especially
effective for immproving the immune response, an energy
intensive process, and for cardiomyopathies.
Conclusions
While sources abound for information on supplements, we caution
readers that not all sources are reliable. The majority of the popular
literature is suspect, with little of it having scientific basis. With
that
caveat, we recognize most western medicines have botanical origins
and that nutrition is an essential path to good health. Amongst the
chaff, there are many grains of wheat. For those looking into
supplements, especially those in the "health food" category for their
pets, we recommend caution, and urge you to seek out those
supplements, such as listed in this article, which demonstratively have
a
scientific basis for their claims. Supplements are not the way to
compensate for a poor diet; change the diet instead.
