The search for a good night’s sleep often leads individuals to the supplement aisle for a dose of melatonin. However, scientists at Mississippi State University (MSU) are unveiling an array of additional health benefits that this hormone could deliver for cattle.
In the Department of Animal and Dairy Sciences and the Mississippi Agricultural and Forestry Experiment Station, faculty members and students have embarked on a journey of discovery. They are investigating the role of melatonin in the bovine body and how this hormone could be harnessed to improve cattle health.
A prominent figure in this field of research is MSU Associate Professor Caleb Lemley, who has a rich history of studying melatonin as a supplement in cattle. For nearly a decade, Lemley has been exploring how this hormone influences blood flow between the dam and the fetus during gestation.
“Over the years, we’ve looked at melatonin’s antioxidant benefits, which help alleviate oxidative stress in the animals and have implications on their cardiovascular health,” said Lemley.
Zully Contreras-Correa, a Postdoctoral Associate at MSU, also shared her insights. “Summer heat is a major stressor for cattle, and in our research here at Mississippi State, we’ve found that melatonin can potentially be used to control the animal’s body temperature,” she said. “At night, when melatonin levels are highest, body temperature is lowest. Our recent research showed that melatonin supplementation during summertime reduced body temperature in pregnant cattle, so we hope to research it further in other livestock species.”
Melatonin, known for controlling the body’s circadian rhythm and responding to light, has fluctuating levels throughout the year. It’s naturally higher in the winter and lower in the summer.
“We just completed a study comparing melatonin supplements given to cattle living in Montana to our cattle at MSU over the winter months, and the differences were notable,” Lemley remarked. “We saw a very limited response in the Montana cattle compared to the Mississippi cattle, so we believe these treatments may be more effective in the Southeast.”
In addition to these findings, doctoral students Riley Messman and Rebecca Swanson have been conducting their own research into the effects of melatonin.
Recently, these scientists published a literature review in the journal Biomolecules, titled “Melatonin in Health and Disease: A Perspective for Livestock Production.” This paper examined over 100 studies spanning six decades, revealing that melatonin — a hormone naturally produced in the brain — functions in ways that extend far beyond its basic role of regulating circadian rhythm.
Messman, during her graduate studies, explored how melatonin affects the microbiome, the communities of bacteria that inhabit the body. “As melatonin levels fluctuate throughout the day and throughout the year, so do bacterial populations,” Messman noted. “So, melatonin is altering the microbiome and the immune system, which plays a role in pretty much every physiological process you could think of.”
Similarly, Swanson has been delving into the role of melatonin in skeletal muscle growth as part of her graduate work. “Nutrient restriction naturally occurs in specific areas of the United States and at certain times of the year,” she said. “Melatonin can help alleviate some of that nutrient restriction and promote the production of amino acids and more efficient muscle growth.”
However, since melatonin is considered a supplement and hasn’t been approved by the Food and Drug Administration, there has been limited research into its full effects and potential benefits. Lemley emphasized that it’s unlikely that traces of the supplement would be present in the muscle tissue at the time of processing.
“Melatonin has a rapid rate of clearance and will leave the body within a day,” he said. “When you consider that and the low cost of supplementing the cattle at 25 cents a day, there are a lot of potential benefits for producers.”
There is much yet to discover about the far-reaching ways that melatonin can support the health of cattle by simply manipulating the levels of this naturally present hormone through supplementation. MSU scientists will continue their work to further discoveries about its benefits.
This work was supported by the Agriculture and Food Research Initiative competitive grant from the U.S. Department of Agriculture National Institute of Food and Agriculture. Additional funding was provided by the U.S. Department of Agriculture, Agricultural Research Service.