Vitamin C continued...

[DixieGrl113]

I wanted to elaborate on this as it was brought up in another thread about enzymes and I don't want to steal that posters thread.

Which organs and/or functions in a dog are affected by vitamin C levels. Either too much or too little. And besides peace of mind, is there any specific reason that vitamin c supplementation would be needed in the canine diet seeing as how they produce their own?

I haven't been able to find any answers tot his question as of yet in any of my "sources" including but not limited to books, WWW and vets. Any help or info would be greatly appreciated. :)

[moondog]

Take a look at this link. It's written with people in mind, but I believe the description of how Vitamin C works in the body would be the same. Dogs produce Vitamin C in their liver, so it seems that it would stand to reason that a low-functioning liver may need to be supported by supplementation.

http://www.howstuffworks.com/vitamin-c.htm

[Sheenagirl]

Evidently the Vets are taking a closer look at the Vit.C supplements. Our Vet said research is being done and that the Vets believe now that Vit.C can prevent certain kinds of cancer in dogs. That's enough for me to start giving Sheena the Vit.C - within the proper dosage can't hurt anything and if it prevents some cancers - it is well worth our pets lives to give it a try! ;)

[Vivianne]

DixieGrl113

Vitamin C

Vitamin C has long been considered the cure for the common cold in humans. In pets, it has been thought to prevent hip dysplasia, cure feline leukemia, and prevent urinary tract infections. We doubt that its use will prevent a dog that genetically carries the trait of hip dysplasia from developing this condition. However, we have worked with several animals that had clinical hip dysplasia, that when given high levels of vitamin C, seemed to exhibit fewer signs of joint pain. It did not cure the condition, but it did seem to allow the patient to better live with the problem.

In the case of bladder infections, as in human medicine, we believe that vitamin C is unusual in that it is excreted unchanged totally via the kidneys, and it therefore, acidifies the urine. This makes the bladder a much less hospitable place for bacteria to live. Most of the bacteria that cause cystitis (bladder infection) survive much better in environments that have an alkaline pH. Therefore, by acidifying the urine with vitamin C, these organisms are often eliminated. This is the reason many women are told to drink large quantities of cranberry juice by their doctors when they have cystitis.

As far as its use in viral diseases like the common cold or feline leukemia, in all honesty, there is little evidence of its value. At the same time, we would readily admit that vitamin C can do no harm when used. As we stated, it is excreted unchanged via the urine.

Forms of Vitamin C: We know that vitamin C exists in two forms: as dehydroascorbic acid and as ascorbic acid. Ascorbic acid is easily hydrolyzed (mixed with water) and therefore, it is readily absorbed through the intestinal wall. Likewise, it easily enters the urine to exit the body. Very little is stored within the body and the minute amount that is, is contained within the adrenal gland. Ascorbic acid can be fed or it can be manufactured within the body from glucose. Unlike dogs and cats, guinea pigs and humans cannot manufacture vitamin C so their only source is in their diet.

Therapeutic Uses: Ascorbic acid plays many important functions in bone formation. It is involved in bone growth as well as bone mineralization. Deficiencies of ascorbic acid result in the syndrome known as scurvy. Dogs with scurvy exhibit weak bones and swollen joints usually accompanied by severe tissue hemorrhaging. Scurvy has not been reported in cats. In young dogs, scurvy is sometimes referred to as hypertrophic osteodystrophy (HOD). Dogs with HOD generally exhibit swollen, painful joints especially of the limbs. The swollen areas are the portions of the long bones that are growing. We might add here that a lack of vitamin C is only one factor in HOD. There are other causes of HOD that are unrelated to a vitamin C deficiency. A puppy may have HOD, but have perfectly adequate amounts of vitamin C. With this in mind, it is easily explained that only some patients with HOD will respond to vitamin C therapy.

Vitamin C is definitely justified as a supplement, especially in fast-growing puppies and in lactating bitches. It is not, however, a cure of hip dysplasia. Hip dysplasia is a genetic conformational abnormality and vitamin C cannot alter genetics. It may help alleviate the pain associated with dysplastic hips, but hip dysplasia is genetic and not nutritional. Whether the dog is in pain or not, or whether vitamin C does or does not help, the dog is still dysplastic and should be treated as such.

Vitamin C has been used with varying degrees of success in helping prevent the formation of some bladder stones in dogs and cats. The vitamin C makes the urine more acidic and maintaining an acid urine helps discourage the creation of most stone types.

In conclusion, vitamin C is widely used as a supplement in growing, pregnant, lactating, stressed, and working pets. There are numerous vitamin C supplements available. There is no concern for vitamin C toxicity.

[rottnkidd]

Excellent post Vivianne! I'm also a serious advocate on the benefits of Vit C. An acquaintance of mine used Vit C intravenously with a dog in kidney failure and literally brought him back to life. She also did that with a bitch that had pyometra and it eliminated the infection and saved her life!! I use a powdered
C with bioflavanoids, which help with the uptake.
kathy

[DixieGrl113]

Now I'm getting some answers...very educational post Vivianne, just the kind of information I've been looking for. Keep it comin' :) I'm bit retentive about adding supplements, if I don't know EXACTLY what it can or is going to do, I'm reluctant to feed it. You all are a great help. Hopefully I can learn more. :)

[alexav]

Vitamin C! Yeah!

Linus Pauling sure knew his stuff!

Doctors say I am alive today because of this powerful vitamin. Vitamin C therapy was considered experimental back then but my mom, who had had so many miscarriages was willing to try anything. It did the trick and I'm here to prove it!:D

[Barbara Surplus]

Originally posted by alexav
Linus Pauling sure knew his stuff!

Indeed he did, and, sadly, the medical establishment vilified him for it. Glad to know that you're living proof of his genius. :)
Barbara

[k&s]

What dose of vitamin C is recommended for dogs?

[rottnkidd]

In a healthy dog, about 1000mg per 50# of body wt. My girl is
90#, and I give her 2000mg a day of a powdered Vit C with
bioflavanoids.
kathy

[Muckdogs]

For anyone interested, check out www.belfield.com for some interesting reading. I think Wendell is on the right track. My only problem with some of his writings is that he seems to cloud the lines of causation of CHD and seems to be a proponent of Vitamin C therapy as a possible cure, not as an alleviating treatment like Viv mentioned above. There is a lot of creedence to the collagen synthesis argument as well as the immunological boosting theories. In short, I use the product and have had nothing but positive results, with no side effects as of yet.

[Ilovemypuppy]

Vitamin C and its role in Stress Management, Bone Metabolism and its influence on the
skin and coat of the dog

By Melvyn John BHS. IT.
VYDEX ANIMAL HEALTH LTD.

In recent years major advances have been achieved in our understanding of the metabolism and the
importance of vitamin C in domestic animals (*Wegger et al., 1984). Numerous studies have shown
that the synthesis and the consumption of vitamin C depend on many factors. In various nutritional
deficiencies and in many diseases of domestic animals the synthesis of vitamin C is reduced and its
concentration in the blood plasma drops.

Owing to a concurrent reduction in the concentration of vitamin C in the cells, the rates of various
biochemical reactions are reduced and the performance of various cell types impaired.
Administration of vitamin C has been found beneficial in dealing with various infectious diseases, hip
displasia, bone development, protein metabolism and stress of domestic animals. The list of
biochemical function that vitamin C is involved in is much more extensive, I have highlighted those
that are relevant to this article.

Of particular interest in veterinary medicine are cases of scurvy which were characterized by painful
swellings of joints being reported in young dogs. In such cases insufficient synthesis or insufficient
uptake of vitamin C has been indicated as the cause.

Various studies have shown that adding small amounts of vitamin C to the food have a beneficial
effect on growth and on improved performance of the immune system.

The following is intended to provide an understanding of the role of vitamin C and the basics of
physiological stress and ways of using this knowledge in practical situations, the influence vitamin C
has on the immune system, the influence vitamin C has on Vitamin D3 and bone metabolism and the
importance of vitamin C for skin and coat.

Much confusion exists as to what stress is, and is not. Consequently, management practices may
result in stress responses often creating situations which aggravate the initial reaction to the stressor.
In order to avoid this we must first understand what 'physiological' stress really is. Physiological
stress is not psychological stress, (the pressures we feel in our daily lives). Physiological stress is the
nonspecific response to any external demand which calls upon the animal to adapt to a new situation.
Life is a constant set of adjustments.

Energy is needed to make these adjustments. Whether the adjustment is either great or small,
physiological stress provides the energy to accomplish the adjustment through nonspecific responses.
For every external demand, or 'stressor' (a situation that causes stress), there is both a specific
response and a nonspecific response. The specific response is unique for each stressor but the
nonspecific response is essentially the same for every stressor. Since the presence of stressors is
constant, by definition the absence of stress would be death. We cannot totally avoid stress, we must
manage it.

The concept of physiological stress was first developed by a scientist named *Selye (1936,1973),
who termed his observations General Adaptation Syndrome (GAS). Selye observed that most
chronically ill individuals exhibited similar symptoms. There are three stages in the 'General
Adaptation Syndrome'. The first is the alarm reaction or the so-called 'fight or flight' reaction.

At this stage a sudden biochemical reaction takes place, (characterized by huge releases of
adrenaline and similar hormones from the sympathetic nervous system). These compounds cause
rapid release of glucose from body reserves (primarily from glycogen). This produces available
energy to elude a stressor. The animal quickly enters the stage of resistance. This is the period when
glucose is formed from less available reserves such as lipids and proteins.

The important aspect of the stage of resistance is that it will continue until recovery from the stressor
occurs or the animal enters the stage of fatigue and dies. The animal dies from either the depletion of
reserves or adrenocortical exhaustion. That is when the adrenal cortex (the source of
corticosteroids) depletes the survival functions which include regulation of heat loss, blood flow and
respiration etc. so that they can no longer be supported. The time course of the three stages of the
'General Adaptation Syndrome' depends upon the severity of the stressor. A chronic stressor
requires small changes over a long period of time.

The adaptation to warmer weather that takes place over several weeks during the start of summer is
an example. An acute stressor requires immediate life-saving adaptations to survive. The sudden
onset of very hot weather creates such a situation. The animal has not had sufficient time to adapt to
the hot weather. In the latter case an alarm reaction is followed by a resistance stage. If the
adreal-cortex is depleted before the stressor is removed, then death will occur.

Although they may seem unlikely, growth and reproduction both call upon the body to constantly
change, and are by definition stressors. With a seemingly endless myriad of stressors, the challenge
for modern animal management is to modify or manage physiological stress. Ascorbic acid (vitamin
C) supplementation has been shown to reduce heat stress related mortality in birds (*Pardue, 1983).
One of the most difficult concepts of physiological stress to understand is suppression of the immune
system. The immune reaction consumes considerable quantities of metabolic reserves. Additionally,
aberrant reactions such as allergic reactions can be harmful and should be suppressed. Vitamin C
has been shown to modify the immune response, *Pardue (1983). Vitamin C has also been shown
to improve reproductive efficiency.

In infectious diseases the food uptake is often reduced and the concentration of glucose in the blood
plasma drops. Under these circumstances the extent of synthesis of vitamin C in the liver of mammals
drops. At the same time the consumption of vitamin C increases because of the increase in secretion
of glucocorticosteroids. Various investigations on domestic animals suffering from certain infections
have shown a reduction in the content of vitamin C in the blood plasma or serum.

In dogs suffering from distemper, administration of vitamin C at high levels for three days or longer
usually results in improvement in the clinical condition and rapid recovery, especially if this treatment
is used at an early stage (*Leveque, 1969). As a rule, an optimal supply level can be achieved by
oral administration of 300 to 500mg vitamin C daily. Studies conducted by *Brehm (1964) indicate
insufficient synthesis of vitamin C in dogs suffering from various diseases.

These studies indicate that vitamin C levels of less than 0.4 mg/dl in a dog's blood plasma are
evidence of insufficient synthesis. Supplementary administration of vitamin C is also advisable after
surgery because it promotes the formation of collagen by the fibroblasts, osteoblasts and osteocytes.
Topical administration of vitamin C into the region of bone fractures stimulates the healing process
(*Pataky et al., 1963).

Parasitic infestation of the liver leads to a reduction in the synthesis of vitamin C which, in mammals,
takes place in this organ.

Many investigations have shown that in diseases of domestic animals displaying higher than normal
temperature and reduced food uptake, the concentration of vitamin C in the blood plasma drops
considerably for some time. In view of the great importance of vitamin C for immune defense and for
regeneration of tissue, administration of vitamin C in daily dosages of 200 to 300mg for small animals
and of 2 to 3g for large animals is advisable.

Scury-like symptoms in dogs are likely to be due to congenital inability to synthesise vitamin C. In
such cases the concentration of vitamin C in the blood plasma is below 0.1mg/dl.

Results of recent trials show that Vitamin C influences bone development and strength through its
effects on the production of vitamin D metabolites and calcium-binding protein.

Vitamin D3 supplied in a feed supplement is transported to the kidneys for conversion to the active
metabolite form. Latest studies show that vitamin C is required to achieve optimum conversion of
vitamin D3 into these active metabolites. Improvements in bone synthesis appear to be directly
related to an increase in the conversion of vitamin D3 to the active metabolite and to the increase of
calcium-binding protein through the influence of supplemented vitamin C in the diet.

At times of stress unfortunately absorption of vitamin C from the gut may not be fully effective,
therefore daily supplementation is recommended.

In large breeds of dogs, hip dysplasia, long considered to be an inherited birth defect, may be an
easily controlled biochemical condition. The lesion in hip dysplasia appears to merely poor quality,
low strength collagen in the affected ligaments. In litters from dysplastic German Shepherd parents or
parents that produced dysplastic offspring, there have been no signs of hip dysplasia when the
bitches were given higher than normal doses of vitamin C during pregnancy and the pups were given
daily doses of vitamin C until they reached young adulthood.

In potentially dysplastic pups of large breeds, the first year or two of life is a high stress period. The
demands on the body are great, the demands for large quantities of vitamin C even greater. The
laxity of the hip ligament and changes in the pectineus muscle and tendon, consequent upon lack of
high quality collagen is evident. The weak collagen in the ligaments causes them to stretch or loosen,
resulting in joint laxity, which allows the young femoral head to separate from the hip socket.

After separation of the femoral head from the acetabulum, an inflammatory process (arthritis) ensues.
Varying amounts of scar tissue form in the acetabulum, preventing the head of the femur from
returning to its normal position. This results in coxofemoral subluxation (hip dysplasia).
Simultaneously, the poor quality of collagen in the pectineous muscles and ligaments retards their
growth and development. The impaired growth and development of tendon and muscle, together
with the rapid growth of the femur, contributes further to the cause of the dislocation.

In trials conducted over a five-year period using eight litters of German Shepherd puppies from
dysplastic parents, or parents known to have produced dysplastic offspring, none of these pups
which have been maintained on high doses of vitamin C have, to date, shown dysplasia. The regime
consists of giving the pregnant bitch high doses of vitamin C in the ration daily. At birth, the pups are
given 50 to 200mg of vitamin C orally.

When the pups reach three weeks of age, the daily amount increased to 500mg until the pups are
four months old. At that time, the dosage is increased to 1 or 2g daily and maintained at that level
until the pups were 18 months to two years of age. This program was so successful that, when selling
puppies, breeders in America involved now incorporate into their sales agreements a clause stating
that the pups are guaranteed dysplasia free only if they are kept on the prescribed regime of vitamin
C.

The skin and the coat fulfill many functions:

Physiological functions such as protection, storage, excretion and the sensory function.

Social functions which partly control their relationships with other dogs (identification, territorial
demarcation, sexual behavior).

Finally, in view of the current role of the dog (and of pet animals in general), functions related to
acceptance in human society.

These aesthetic functions are probably of the greatest concern to most dog owners.

Skin disorders are particularly frequent in the dog and may be due to a wide variety of causes.

For example:

Infectious dermatitis;

Allergic or contact dermatitis;

Alopecias of hormonal origin, other skin changes, thyroid deficiency;

Ectoparasites and their direct or secondary consequences (demodectic mange);

Disorders of dietary or nutritional origin; for example, liver and kidney disorders or overloads, or
deficiency conditions.

Despite this list the relationships between diet and the condition of the skin and coat are often
considered self-evident, not only by breeders and owners, but also by veterinarians. The skin and
the coat may show primary lesions caused directly by specific nutritional deficiencies or excesses,
but similar effects may appear as secondary symptoms of disorders of the gastrointestinal tract, the
liver or the kidneys.

Vitamin C has a direct influence on the lustre of the coat through its influence on the efficient
metabolism of other key micronutrients like amino acids, B complex and vitamin E.

Where diets are deficient in vitamin C metabolism of sulphur-containing amino acids will be impaired.
As the coat in mainly made up of these amino acids the coat can never reach its full potential. A
reduction in fur growth, possible irregularity in growth pattern, reduction in pigmentation and the
activity of the hair follicles and potential loss of fur. The amino acid lysine is a vital component in the
metabolism of muscle tissue-this amino acid is also dependent on vitamin C.

Vitamin C appears to be involved with the absorption of iron from the gut. It is also required for the
synthesis of hemoglobin and is necessary for the development collagen in skin. Vitamin C plays an
important role in the healing process of wounds.

Summary

Under conditions of acute stress, animal can not synthesise sufficient vitamin C to alleviate many
detrimental effects associated with stress. Due to the vital link of vitamin C and bone metabolism and
the development of collagen in teeth, bone, skin cartilage and amino acids and the improvement in
the immune system response to disease challenge. Supplementation of vitamin C should become part
of standard management procedure and increased particularly when known stressors are to be
imposed.

References

Animal Nutrition (McDonal, Edwards, and Greenhalgh)
Vitamins in Animal Nutrition (arbeitgemeinschaft Wirkstoffe Tierernahrunge (AWT) (Wegger et al.)
1984; (Selye) 1936, 1973; (Pataky et al.) 1963; (Pardue) 1983; (Leveque) 1969.