ADAPTIVE MECHANISM of EXoTIC CATTLE

Submitted by:- Praveen Sangwan & Parveen Ahlawat

Submitted to:- Dr. Pradeep Bamal

INTRODUCTION

• 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.

ADAPTATION

• Barker (2009) defined adaptedness as the state of being adapted, the ability of breeds to produce and reproduce in a given set of environment

• 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 climate change?

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 .

Continued……………

Cows have adapted to food availability with rumen digestion.

Hide insulation also changes to favor conservation or depletion of heat .

Adaptation mechanisms to global warming

To cope with nutritional and environmental stresses cattle developed some adaptation mechanisms . Some of these mechanisms are reported below :-

• Behavioural, digestive and metabolic mechanisms

• Physiological mechanisms

Behavioural, digestive and metabolic mechanisms

Behavioural, digestive and metabolic mechanisms

• 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 practices

• 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 environment .

• 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 specific conditions.

CONCLUSION• So , the Exotic cattle can be adapted to

various climatic conditions to maintain its high productivity level by following means

• 1) Natural means

a) Physiological,

b)Metabolic, digestive

c) Genetic

2) Artificial means

a) Animal husbandry practices

b) Breeding

THANKS