Biomedical Engineering Reference
In-Depth Information
oxidative stress, their ability to eliminate ROS
can be compromised or exceeded. In such cases,
dietary supplementation of antioxidants such as
vitamin E, vitamin C, carotenoids, Zn and Se can
be beneficial to eliminate damaging ROS and in
maintaining normal cellular functions and health
(Chew and Park
2004
; Chandra and Aggarwal
2009
; Maurya
2011
; Aggarwal et al.
2012
) .
(
2001
) requirements for vitamin A and supple-
mented with 300 mg/day of b -carotene (Dahlquist
and Chew
1985
) . Supplementation of vitamins
and minerals is required during the dry period
and early lactation. Plasma concentration of
b-carotene in dairy cows should be >3 mg/L for
optimum udder health. Elevated serum retinol
during the prepartum period has been shown to
be associated with a decreased risk of clinical
mastitis during the first 30 days postpartum.
7.1.1 Vitamin A
Vitamin A and its retinoids have significant
effects on various components of immunity,
including lymphopoiesis, apoptosis, cytokine
expression and antibody production. Vitamin A
has also been observed associated with the inhi-
bition of Type 1 lymphocyte cytokine production
(Frankenburg et al.
1998
) and the proliferation of
lymphocytes (Semba
1994
) .
Most of the fat-soluble vitamins, such as
retinol, a -tocopherol and b-carotene plays role as
antioxidant in the body, decrease at the time of
parturition and have been reported to be associated
with severe health problems in high-producing
cows (Chandra and Aggarwal
2009
; Maurya
2011
). Periparturient cow undergoes intense
mammary growth, copious synthesis and secre-
tion of carbohydrates, fats, proteins as well as
marked accumulation of colostrum and milk.
Since colostrum is rich in vitamins A and E, cow
requires increased supply of these vitamins prior
to parturition. Providing vitamin A orally to dry
cow or by intramuscular injection at drying off
prevents deficiency of vitamin A. Retinol levels
above 0.8 mg/ml are necessary for optimum
immune function. b -carotene supplementation
enhances the per cent intracellular kill by blood
phagocytes. Dairy cows supplemented with 300
and 600 mg BC/day have higher killing ability
against bacteria in the peripartum period (Michal
et al.
1994
) . However, supplementation with
500 mg BC/d/h results in reduction in somatic
cell count (SCC) by 300,000 cells/ml milk and
more number of animals were observed to have
SCC below 200,000 (Hasselmann et al.
2000
) .
The results on supplementation with vitamin A
and B-carotene on mastitis are inconsistent.
Positive effects have been reported when cows
were given diets that approximately met NRC
7.1.2 Vitamin C
Vitamin C, also termed as ascorbic acid, is a
water-soluble antioxidant vitamin that is impor-
tant in the formation of collagen, tendons, liga-
ments, muscle and blood vessels. Vitamin C also
plays an important role in the synthesis of the
norepinephrine, a neurotransmitter and hormone
produced in the adrenal medulla. Norepinephrine is
critical to brain function and the body's response
to stress. The requirement of vitamin C in the body
is very less, to protect proteins, lipids, carbohy-
drates, DNA and RNA from damage caused by free
radicals and reactive oxygen species, which are
generated during normal metabolic processes and
immune cell activity, especially in periparturient
cows. An equally important property of vitamin C
may be its ability to regenerate other antioxidants,
such as vitamin E (Carr and Frei
1999
) . The bene-
ficial role of vitamin C has also been observed in
cattle due to its interaction with other antioxi-
dants, such as vitamin E (Cusack et al.
2005
) .
7.1.3 Vitamin E
Vitamin E is an important and essential fat-soluble
antioxidant vitamin for body immunity and
reproductive function of animals. As an antioxi-
dant, vitamin E protects cells against free radicals.
In addition to its antioxidant properties, vitamin
E has a supportive role for maintenance of the
immune system, DNA repair and other metabolic
processes (Traber and Arai
1999
; Aggarwal et al.
2012
). Vitamin E is an important constituent of
all the cell membranes (plasma, mitochondrial
and nuclear) and is the major antioxidant in body
tissues. Vitamin E is found throughout all cells of
the body and is more concentrated in the immune
cells to provide protection against the destructive
