Environmental Stress Effects on Production
Its that time of year when the weather turns nasty and temperatures fluctuate across the county. The effect cold temperatures have on cattle and calves is profound and we certainly can’t predict what the weather will do but the yo-yo effect of up and down temps coupled with dealing with other stresses on the herd can see body condition drop, increase chances of illness and the need to increase the amount of total feed.
Cold, snow, wind and mud have an immense effect on the digestive and immune system of animals causing delayed immune responses to illness, lower ability to deal with illness, increased calorie requirements, lower weaning weights, lower cow reproduction numbers, and sick calves. The digestive tract makes up about 70% of the animal’s immune system, when the digestive system is not working optimally so goes the immune system.
Cattle can sometimes deal and adapt to short term changes in the weather without any large impacts on performance but large temperature swings within the span of 12 -24 hours or long days of frigid temps tend to cause decreases in feed and water intake.
We all know that cattle do well when it’s not too warm and not too cold, but during the wintertime when the ambient temp falls below the lower critical level for the cattle based on body condition, hair coat, dry or wet conditions, these cold stressed animals will then need increased nutritional needs especially calves who are using their energy for growth as these cold weather conditions cause animals to divert more energy to staying warm and maintaining body temperature.
Not only does the weather cause stress in animals but also on the land that we use for feed. The drought that Alberta saw this year challenged the rangeland and saw many herds come in early September/October instead of later December. That meant feeding forage and rations earlier than expected. Some forages and grains were subjected to higher mycotoxin levels since mycotoxin excel in drought conditions. This then leads to some herds dealing with higher mycotoxin levels leading to reduced reproduction numbers, poor body conditioning, poor growth rates in young stock, and increased rates of various illnesses.
The increase in dry matter intake for cattle in cold stress triggered by the animal’s metabolism increase can put stress on rumen and digestive tract passage of feed. Digestive and immune stress on animals tends to go with cold stress. One way to deal with this is to use a direct-fed microbial (DFM). DFM are products such as yeast, probiotics and prebiotics and combinations of those products. They are usually mixed in with rations or given in paste form to resolve immediate issues such as scours, animals off feed or to prevent issues in day-old calves.
DFM increase fibre digestion, essentially helping heat the animal, increase dry matter and water intake, increases nutrient uptake, increase daily gain in calves and helps in assisting the digestive system deal with toxin overload, and other immune challenges by kick-starting the immune system and providing toxin binding action and flourishing the rumen with beneficial microbes.
Key management strategies for dealing with environmental stress
Avoid overcrowding of feedlots to reduce infection
Provide windbreaks or shelters
Provide ample bedding in sheds and shelters for comfort and warmth
Provide additional feed during times when the temps fall below critical levels for your herd, especially for cows in the last trimester.
Monitor calves who have a lower threshold for cold weather
Provide fresh water. Frozen water sources limit water intake and reduce feed intake
Provide a direct-fed microbial to a ration or directly in paste form to an animal to assist digestion and immune health
We can’t control the weather, but we can reduce its effects on the digestive and immune health of the animals. By using key management strategies and direct-fed microbials we can reduce the costs of illness and improve overall herd efficiency.