MANAGE STRESS IN HERDS TO AVOID ILLNESS

by: Christine B. Navarre
DVM, MS, DACVIM, Extension Veterinarian, Louisiana State University Ag Center

The positive nutritional benefits of beef in our diets are undeniable. So how do we keep producing a safe and satisfying product? We follow Beef Quality Assurance Guidelines. And a major component of the BQA program is managing stress.

Stress is a fact of life for both animals and people. We can't escape it completely. But severe stress is harmful to our bodies. There are many negative effects of stress on health, but two really impact beef production: immune system suppression and muscle wasting. Muscle wasting is obviously very detrimental when we are trying to grow calves and keep cows in good body condition. But immune suppression has many consequences.

When the immune system is suppressed, animals are more likely to get sick. Sick animals don't grow, grade or reproduce to their genetic potential, even if they recover. Since cattle are prey species and hide illness very well, we may not always recognize it. But they are still not performing.

Immune suppression also impacts response to vaccinations which additionally increases the risk of disease. When we do recognize illness we might need to treat them with pharmaceutical products. The more animals we treat the more risk we have for an accidental drug residue.

Another serious consequence of stress is appetite suppression. While people may go for the carton of ice cream during stressful times, cattle don't eat. When they don't eat, they don't drink. Lack of nutrition and dehydration both further suppress the immune system, setting up a vicious cycle. Stress also utilizes more of the nutrients that animals do intake. This increases the cost of getting to our production goals.

Stress can be acute or chronic. Examples of acute stress would be weaning, castration and dehorning, transportation, stressful handling and diet changes. Examples of chronic stress would be heat and lack of proper nutrition. Each one of these stresses alone depresses the immune system and impacts production and beef quality. When we add multiple stressors together, the impacts are more severe.

There are three ways we can try to minimize the overall impact of stress on our beef cattle. We can eliminate a stressor, reduce the severity of a stressor, and aroid multiple stressors at one time. The following are examples of stressors that we should manage on our cow-calf operations.

Nutritional Stress

Proper nutrition is the foundation of healthy and productive animals. If we eliminate all other stressors, but don't feed animals properly, we will have poor production and an immune system that can't function to respond to vaccines or disease challenges. And from research of fetal programming and epigenetics, we know that poor nutrition in one year has negative impacts on multiple generations of cattle.

Disease

A well thought out vaccination program as well as a biosecurity plan are essential to decrease the risk of diseases. Remember that vaccines won't work very well unless all other stressors are in check.

Parasites

Internal and external parasites suppress the immune system and appetite. A good control program that takes into account increasing parasite resistance to anthelmintics and pesticides is a must.

Weaning

We can't avoid weaning, but we can make it less stressful. Fence line weaning and the use of nose flaps are both proven to have positive benefits. Creep feeding, not necessarily for the increased gains, but to decrease the stress of diet change, can also be considered. Having calves castrated, dehorned, vaccinated and dewormed well before weaning avoids the additive effects of multiple stressors at once. Holding calves for 4-5 days and avoiding commingling as much as possible before shipping are also good practices.

Castration and Dehorning

Polled genetics can eliminate the stress of dehorning, but this is not the right choice for everyone. Performing both of these procedures at a very early age is best. There are also very easy and inexpensive techniques that can block some of the acute and chronic pain associated with these procedures. Producers can talk to their veterinarians about learning these techniques.

Handling

Aggressive handling leads to bruising, decreased response to vaccines, appetite suppression and poor reproduction. Feeder calves that are handled with as little stress as possible have less sickness, increased weight gain without additional inputs, and higher quality grades. If you want to get the most out of your vaccines or AI program in your females, then avoid aggressive handling which will negate your efforts.

Weather

We can't avoid heat in the Southeast, but we can do some things to keep the impacts of heat stress to minimum. If Brahman-influenced cattle don't fit in your operation, acquire non-Brahman-influenced cattle from herds established in the Southeast. Provide adequate shade and plenty of fresh water. Make sure water and shade are close together as cattle may be reluctant to leave shade to travel far to water. This can lead to deadly consequences.

Cold stress can also be a problem in some years. Cold temperatures, rain and wind can be a deadly combination, especially in more heat tolerant animals. Everyone should have a plan for how to deal with colder than normal conditions. Temporary shelter/wind blocks and extra feed will be needed to minimize the negative impacts that one cold year can have on production for several years.

Another consequence of rain is mud. Slogging through mud is like cow aerobics. It uses up energy that is expensive to replace with feed. This is exacerbated when cows don't have a dry place to lie down. Mud is almost impossible to avoid in the Southeast, but should be controlled as much as possible.

Conclusion

For years we have poured a lot of resources into genetic selection. But if we don't give cattle all of the tools they need to allow those genes to be expressed, we've wasted our efforts. Proper nutrition and decreasing stress as much as possible will give us the best chance of reaching our production goals.

Let's feed cows, not stress.







Don't forget to BOOKMARK  
Cattle Today Online!