VITAMINS can be divided into two
families: vitamins that are soluble
in fats (liposoluble vitamins),
namely vitamins A, D, E and K, and
vitamins that are soluble in water
(hydrosoluble vitamins), namely
vitamins B and C.
In general, a
balanced diet
and additional
synthesis by
the intestinal
bacteria
guarantee a
sufficient intake
of B vitamins,
although intake can become marginal
in situations of major water loss. This
is because of the water-soluble aspect
of B complex vitamins and the fact
that they cannot be stored.
Riboflavin (B2), niacin (B3),
pantothenic acid (B5), pyridoxine (B6),
inositol (B7) and biotin (B8) are all
important for the quality of the skin
barrier function. Deficiencies can lead
to dry flaky seborrhoea accompanied
by alopecia, anorexia, weight loss and
pruritus. As an example, a deficiency in riboflavin can lead to head and neck
alopecia, especially in cats.
Cats have high requirements in terms
of water-soluble B vitamins and they
are unable to convert β-carotene into
retinol (the active form of vitamin A).
This shows us that these companion animals are adapted to a carnivorous
diet under natural conditions, since
these vitamins are present in large
quantities in animal tissues.
The skin barrier cocktail
The Waltham Centre for Pet Nutrition
screened 27 substances that were
thought to provide a beneficial effect
on skin function. The selection
criteria were based on limiting water
loss through the epidermis and the
synthesis of skin lipids. From this, the Centre identified four B vitamins and
one amino acid acting synergistically
to improve the barrier function of the
epidermis and decrease trans-epidermal
water loss. They were:
- pantothenic acid which is involved
as a co-enzyme in many metabolic
pathways, including those of fatty
acids; - inositol and choline which
work together in the formation
of cell membranes – combined
with phosphorus, choline forms
phospholipids; - niacin, which is synthesised from
tryptophan, is essential for cellular
respiration and also vital for a healthy
and pliable skin; - histidine is essential for the growth
and maturation of the epidermal cells
(keratinocytes).
Together, this “PINCH” cocktail
acts in synergy to promote the
synthesis of ceramides (skin lipids
necessary for the integrity of the outer
layer of the epidermis). However, due
to the time needed for the epidermal
cellular differentiation process, these
nutrients will only have a beneficial
effect after approximately two months
of administration.
Vitamin B12’s benefits
In addition to those B vitamins
already mentioned, vitamin B12 is
important for pets. It is involved in
many essential biochemical reactions as
a co-enzyme and plays a primary role
in the synthesis of proteins and the
production of red blood cells.
Also known as cobalamin, vitamin
B12 is mainly found in animal products
( sh, meat and offal) and is very stable
during the heat treatment of food
products. It is the only vitamin to
incorporate a mineral element in its
chemical formula, namely cobalt.
Cobalamin plays an essential role
in the synthesis of nucleic acids (in
synergy with folic acid). A deficiency
disrupts protein synthesis, especially for fast-regenerating tissues like
haematopoietic tissue.
A fall in the body’s cobalamin
reserves can be seen in cats and
dogs suffering from issues with their
pancreas or liver. The depletion of
reserves may be explained by chronic
dysorexia or intestinal malabsorption
reducing the quantity of cobalamin
available to the animal.
The deficiency may also be
secondary to an insufficiency of
intrinsic factor essential to the
absorption of cobalamin. This
glycoprotein is synthesised only by
the pancreas, so impaired function
of the pancreas is a risk factor for
deficiency. Any imbalance in the
intestinal bacterial ora is also likely to
reduce the absorption of cobalamin, as
intestinal bacteria use vitamin B12 and
may also form connections to intrinsic
factor.
Cats and dogs are not able to store
large quantities of cobalamin in
the body and they quickly become
de cient when their homoeostasis is
disrupted. Therefore supplementation
of vitamin B12 is essential for the
nutritional management of cats and
dogs with impaired pancreatic or
hepatic function.
- For further reading visit vetportal.royalcanin.co.uk (or vetportal.
royalcanin.ie for Ireland).
