ADAPTIVE MECHANISM of
Submitted by:- Praveen Sangwan &
Submitted to:- Dr. Pradeep
• Now a days , Exotic cattle is going to be
very important enterprise for its ultimate
users/ farmers as its milk productivity is
comparatively higher .
• Several mechanism should be adopted by
cattle, like behavioral ,metabolic,
physiological etc., to escape from various
harsh conditions i.e. climatic change,
global warming etc.
• Barker (2009) defined adaptedness as the
state of being adapted, the ability of breeds
to produce and reproduce in a given set of
• Adaptability is then a measure of
potential or actual capacity to adapt .
Climate change adaptation
It can be considered in two ways:
i) How can animal genetic resources cope
with and adapt to climate change while
continuing to contribute to food security
and rural livelihoods?
ii) How can the option value of genetic
resources be maintained and potential loss
of diversity minimized in the event of
How have cows adapted ?
To conserve body heat , cattle have
adapted by adjustment in behavior
(seeking shade) , evaporative heat loss
(panting & sweating) and circulation of
blood (vasodilation) .
Cattle have the ability to adapt to change
in ambient temperature by changes in
metabolic rate .
Cows have adapted to food availability
with rumen digestion.
Hide insulation also changes to favor
conservation or depletion of heat .
Adaptation mechanisms to global
To cope with nutritional and
environmental stresses cattle developed
some adaptation mechanisms . Some of
these mechanisms are reported below :-
• Behavioural, digestive and
• Physiological mechanisms
Behavioural, digestive and
Behavioural, digestive and
• Severe underfeeding :- is associated with
body reserve mobilisation and the
establishment of mechanisms for saving
limiting metabolites (glucose and amino
acids) and a reduction in the basic
metabolic and energy expenditure through
reduced movement and walking by the
animal (Blanc et al., 2006).
• Dehydration :- The capacity of the
kidney to concentrate urine and its ability
to reduce water loss during dehydration is
directly related with the relative kidney
medullary thickness (RTM).
• The greater the RTM, the greater the
ability of the kidney to reabsorb water.
Sustained water restriction resulted in the
activation of water saving mechanisms
• Salty water :- Exposure to saline
water results in an induction of enzymes in
the ileum, liver and kidney.
• The main enzyme is NaK ATPase that
increases the pumping of sodium out of
cells and potassium return to the
intracellular space. The induction of this
enzyme is a powerful adaptive mechanism.
Physiological mechanismsPhysiological mechanisms
• Thermal stress :- Acclimation is now
identified as a homeorhetic process under
endocrine control. The process of
acclimatization occurs in 2 phases (acute
and chronic) and involves changes in
secretion rate of hormones, as well as in
amount of receptors in target tissues. The
time required to complete both phases is
weeks rather than days.
Adaptation of husbandry
• Frankham(2009) notes that the direct
effects of climate change on housed
livestock are expected to be small, as
management can compensate for losses in
animal fitness by modifying the
• Freitas et al. (2006), for example, found
that effects of heat stress were smaller in
larger herds, which were more likely to
afford high-efficiency cooling devices
Breeding for climate change
adaptation and mitigation
• (Easterling et al., 2007) projections
suggest that there should be inclusion of
traits associated with thermal tolerance in
breeding indices, and more consideration
of genotype-by-environment interactions
(GxE) to identify animals most adapted to
• So , the Exotic cattle can be adapted to
various climatic conditions to maintain its
high productivity level by following means
• 1) Natural means
2) Artificial means
a) Animal husbandry practices