Summer heat stress and the role of antioxidants

Animal Nutrition Views

Ioannis Mavromichalis, Ph.D., gives his views on poultry, pig and dairy nutrition based on his experience as a nutrition consultant with clients around the world.

Summer heat stress and the role of antioxidants

While we go to great lengths to protect feeds from oxidation, we should also take care of heat stress-induced oxidation inside the animals.

Summer, heat stress and oxidation are all common terms associated with animal feeds when the temperature goes up, especially in areas with high humidity.

This is nothing new, and experienced feed makers usually increase antioxidants like butylated hydroxytoluene (BHT) in feeds to prevent mostly lipid oxidation and the subsequent feed refusal.

But we forget that heat stress also affects the animal, causing internal oxidation as the organism struggles to counteract the negative effects of elevated body temperatures. This is independent of feed consumed, but consuming oxidized feed does not help. Nevertheless, while we should do our outmost to protect the feed from summer heat stress-induced oxidation, we tend to ignore the same when it comes to the animal itself.

There are natural and synthetic antioxidants that can help animals cope with summer heat stress by ameliorating the negative effects of oxidation. Such is the case with ascorbic acid (vitamin C), which is known to help animals suffering from heat stress. Vitamin E and selenium are also good antioxidants used in many functions within the organism, where they are sacrificed (oxidized) to prevent other valuable components from damage.

In addition, with the advent of phytogenics, we have come to appreciate the plethora of natural compounds with antioxidant properties. Some are already used, not for this purpose, however, whereas myriad others go unexplored or undervalued. This is a great opportunity for us to help our animals and the profitability of our farms.

It should not escape our notice that phytogenics (call them spices if you like) are consumed by humans in great quantities in areas where heat and humidity create almost unbearable conditions. A coincidence? Perhaps, but let us also not forget that such compounds exist in plants that also live in such conditions.