ENVIRONMENTAL PHYSIOLOGY

Meaning of Environmental Physiology

Environmental physiology is the study of interrelationship between an organisms physical functioning and its environment. Environmental physiology refers to the effects of the environment on the growth and performance of farm animals. Too high or too low of any of the elements of weather causes negative effects on the wellbeing of the animals.

Effects of Changes in Climate on the growth of farm animals.

Effects of Extremely High Temperature on the Growth of Farm Animals

Extremely high temperature leads to the following:

i   Panting of chicks and sometimes shouting

ii Reduction of feed intake in poultry

iii Increase in water intake.

Effects of Extremely Low Temperature on the Growth of Farm Animals

i Retarded growth or even death of monogastric animals

iiReduced feed conversion efficiency

iii Mortality  of birds increases through huddling and suffocation

Effects of High Relative Humidity on the Growth of Farm Animals

High Relative humidity causes the following:

 Reduces feed intake of farm animals

ii Causes mouldiness of feed In poultry leading to low feed intake and retarded growth.

Effect of High Intensity of Radiation on the Growth of Farm Animals

High Intensity of radiation affects the food intake of farm animals.

 Effects of High Rainfall on the growth of Farm Animals.

High rainfall causes the following

I Reduces growth

Ii May even lead to death

Iii There is high multiplication of insects such as tsetseflies which transmit trypanosomiasis.

Effect of Wind on the growth of Farm Animals

Wind causes the following

i It aids the spread of diseases e.g tuberculosis

ii The growth of animals is retarded

Iii May even leads to death.

Effects  of Changes in Climate on Reproduction

Reproduction  in animals are affected when there is sharp changes in climatic conditions in environment  where animals are reared. The following  can be noticed:

1. Low rate of conception or fertilization in farm animals when the temperature is high.
2. Frequency of mating , quantity and quality of semen is increased when temperature is increased.
3. Ovulation in farm animals decreases with increase in the environmental temperature.
4. Reproduction capacities  of farm animals reduce  at intensity of radiation.
5. Heat stress causes abortion in farm animals.
6. Sexual maturity is controlled by light intensity in poultry.

Effects of  Changes in Climate on Egg Production

The production of eggs by poultry birds is also affected by changes in the prevailing climatic conditions of an area. The following changes  could be observed :

Egg Production is lowered at high temperature

Eggs storage period is reduced at high temperature

Hatchability of eggs is reduced at high temperature.

Birds tend to drink more water at high temperature which also affect eggs production

Egg production is reduced at high humidity

Birds egg-laying reduces when they are kept in the dark most of the time

Effects of Changes in Climate on Milk Production

Milk production can either increase or decrease in animals like cow ,ewe , or doe as a result of changes in environmental  conditions. The following changes could be noticed.

Milk production reduces at high heat condition.

Dairy animals are affected at high temperature or high rainfall

Milk production is affected as pathogens growth increases due to high relative humidity in the environment.

Tsetse fly growth is favored by high rainfall, thus increases transmission of trypanosomiasis  which reduces milk production in farm animals.