A study published in the Journal of Endocrinology says that happier cows make more nutritious milk. The findings could pave the way to improvements in cow health and milk production.

Although cows are great sources of dairy products, they are still vulnerable to health complications that result from milking. It turns out that cows can suffer from hypocalcemia or lower-than-normal calcium levels, especially before and after giving birth. In fact, analysis shows that about 5 to 10 percent of the North American dairy cow population suffers from the condition.

This condition also affects dairy farmers that depend on milk production and regular pregnancies for profit. When cows have low calcium levels, they are more prone to immune and digestive complications, less likely to get pregnant and their pregnancy gap lengthens.

nutritious milk

Happy cows make more nutritious milk. Credit: Wiz Science/Youtube

For many years, researchers have tried to solve this health problem. They found that hypocalcemia in mice improved with serotonin. Now, researchers from the University of Wisconsin-Madison thought of injecting serotonin, a neurotransmitter associated with feelings of happiness, into 12 Jersey cows and 12 Holstein cows, the two most common cow breeds.

The cows’ milk and circulating blood were then measured. Overall, the team found that the chemical improved the cows’ calcium levels.

However, both cows experienced different benefits. Holstein cows experienced higher levels of calcium in their blood but lower calcium in their milk. On the other hand, serotonin increased calcium levels in Jersey cows’ milk but did not do anything to their blood calcium levels. Milk production in both cow breeds was not affected.

Further investigations are still needed to determine what caused this difference between the breeds. The next step would also involve analyzing how serotonin affects calcium amount at a molecular level.

“We would also like to work on the possibility of using serotonin as a preventative measure for hypocalcaemia in dairy cows,” says lead researcher Laura Hernandez. “That would allow dairy farmers to maintain the profitability of their businesses whilst making sure their cows stay healthy and produce nutritious milk.”