By Emily N. Lenhard on June 18, 2019
Featuring Ángel Abuelo

Concepts

What is oxidation?

Oxidation is the reaction that occurs when an atom loses an electron. Oxidation can be good or bad, depending on where it occurs. It can cause rust on your car or help your body fight off pathogens.

When an atom oxidizes, it can steal an electron from another atom, which causes that atom to oxidize. This electron shuffle continues, and any atom affected remains permanently changed; they are now free radicals.

What are antioxidants?

Antioxidants are compounds that can give electrons to free radicals without becoming oxidized themselves. This stops the electron shuffle that is oxidation.

What is oxidative stress?

When our bodies have too many free radicals and not enough antioxidants to negate harmful oxidation, we experience oxidative stress, which causes permanent damage to cellular structures, such as DNA, fatty acids in cell membranes, and proteins. So, instead of working for you to fight off infections, your free radicals can work against you and weaken your immune cells. This makes you susceptible to infections and other diseases. The same thing happens in other animals—for instance, calves.

“Antioxidants! Eat your fruits and veggies. Make sure you get your antioxidants!”

We’ve all heard this before. In the health world, antioxidants are a frequently broached topic as something that’s good for us—but why? And if they’re good for us, are they good for other animals, too?

One scientist at the MSU College of Veterinary Medicine is researching antioxidants with dairy calf health and management in an effort to improve immune system function and lower production costs.

What’s the problem?

In the United States, the average national mortality rate for dairy calves fluctuates between 6 and 10 percent. 80 percent of those deaths are due to infectious diseases.

But, calves’ immune systems aren’t developed enough for vaccines to be fully effective, so they’re at a higher risk of disease during their first 60 days of life. By that time, calves could already be infected, which can lead to the use of antimicrobials. In fact, approximately 30 percent of calves suffer from at least 1 disease during their first 2 months of life. Pneumonia and diarrhea-causing illnesses are the most common diseases these calves experience. 95 percent of those with pneumonia and 76 percent of those with diarrhea are treated with antimicrobials.

While antimicrobials can treat disease, their misuse also may harm the calves, dairy consumers, and the environment. This includes the generation of antimicrobial-resistant bacteria. It also puts financial strain on dairy producers; approximately 20 percent of dairy production cost is due to rearing costs, which is the replacement of production cows. In addition, experiencing a disease during the neonatal period has life-long impacts. Calves that suffer from a neonatal disease show lower milk yields and decreased reproductive efficiency when they reach their productive life at around 2 years of age.

How might antioxidants be able to help?

Dr. Ángel Abuelo, assistant professor of Cattle Health and Wellbeing in the College’s Department of Large Animal Clinical Sciences, is researching the use of antioxidants to ramp up calves’ immune systems faster, with the goal of making vaccines effective sooner.

Newborn calves experience oxidative stress during their first weeks of age. This is partly due to the start of respiration after birth and partly due to the high metabolic rate experienced during this stage to support growth. Newborn calves double their birthweight in 8 weeks; this means they grow approximately 1.5 pounds per day. Abuelo wants to use antioxidants to control the oxidative stress, which will stop damage being caused to immune cells. He hopes this will bolster the immune system, and then the calves can fight off disease more effectively.

What is being researched?

Abuelo is working under a $500,000 grant from the United States Department of Agriculture to isolate lymphocytes, which are immune cells, from neonatal calf blood. He is using these cells to study which immune functions become altered under oxidative stress. Once these functions are identified, Abuelo will work to see if it’s possible to restore these functions using micronutrients in the form of antioxidants. Subsequently, these micronutrients will be supplemented to newborn calves to determine the extent to which the micronutrients may improve the response of the immune system to vaccination and increases calves’ resistance to disease.

This research aims to provide scientific evidence for the use of nutritional interventions that ultimately improve calf health and wellbeing, reduce antimicrobial usage, and increase dairy farm profitability.