Cold Stress on Dairy Animals
European cattle tend to be tolerant to cold but in our India there is problem for the dairy animals to tolerate cold stress. There is reduction in milk yield and in severe cold causes death. It is the reason why the impact of cold stress on nutrient utilization and animal performance has received less research attention.
Dairy animals are housed in the sheds that minimize the impact of environmental temperature fluctuations on the animals. During the last decade uninsulated loose housing cowsheds for dairy cattle have become common also in northern countries. The temperature in the animal's rooms is only a few degrees higher than the temperature outside the cowshed. This trend in dairy cattle keeping increases the importance of cold stress investigations.
The effects of cold stress on metabolic and physiological adaptations of dairy animals
These are the following systemic reactions take place in animals suffering from cold stress:
- Increased dry matter intake
- Increased rumination
- Increased gastrointestinal tract motility
- Increased rate of passage of feed and liquid in the rumen and digestive tract
- Increased basal metabolic rate and maintenance energy requirements
- Increased oxygen consumption
- Increased cardiac output
- Increased adrenalin, cortisol and growth hormone levels
- Increased lipolysis, glyconeogenesis, glycogenolysis
- Increased hepatic glycose output
- Decreased rumen volume
- Decreased dry matter digestibility
- Decreased insulin response to a glucose infusion
- Decreased temperature of skin, ears, legs
There are a number of factors that alter the effects of cold temperatures on animals: wind, hair depth, hair coat conditions etc. It is important to emphasize the value of a clean, dry hair coat and clean dry environment with minimal wind for animals exposed to low temperatures. For the dairy animals cold should be considered as a local problem.
Steps to reduce cold stress:
- Make sure the waterers or water tanks are not frozen
- Cold increases need of more feeds for animals. Hay provides more heat during digestion than concentrate feeds.
- Do not close eave inlets. This will restrict the ventilation rate and create wet, damp conditions.
- Prevent draught. Animals need dry, draught-free resting area.
- Use ample amount of good, dry bedding
Having dry teats when the dairy animal leaves the parlor is important. One way to lessen the risk is to dip the teats, allow the dip of about 30 seconds and then blot dry using a paper towel.
