June 14, 2016
By John Hutcheson, Ph.D.
This is the second post in a two-part series looking at both health and nutrition considerations to help ensure cattle on arrival are ready to thrive.
One of the first stressors a calf encounters after leaving the farm of origin is weaning; then during the marketing system, it might experience feed and water deprivation. Weaning is a physical stress, which is generally impossible to alleviate; however, management techniques, such as preweaning and preconditioning, have been shown to be an effective way to reduce stress.
Feed and water deprivation have significant nutritional consequences. Cattle subjected to the stressors of marketing and shipping encounter other metabolic changes, one of which is weight loss, primarily due to losses of body and digestive tract water. It has been well established that protein and energy malnutrition severely depresses the immune system.
Other nutrients play an important part of a healthy immune system. In recent years, the positive effects of trace minerals have been documented. The trace minerals – zinc (Zn), copper (Cu), manganese (Mn), selenium (Se), vitamin E – and macro minerals, such as potassium (K), have been shown to be involved in immunocompetence and are critical to optimum performance during periods of stress.
Many changes, metabolic and biochemical, occur during different types of stress. The most observed variable is a decrease in feed intake. Stressed cattle need higher percentages of key nutrients due to lower feed intake, so extra care should be taken when formulating their diets. Energy, protein, potassium, selenium, copper, zinc, manganese and vitamin E need to be considered for newly-arrived feeder cattle.
Additionally, cattle should be given a ration that is highly palatable, contains a good quality roughage source, and meets the nutrient needs of cattle at a low level of feed intake. They also should have access to plenty of good quality water.
Consult with your nutritionist and veterinarian to make sure your receiving program meets the needs of your cattle operation.