Two Jersey cows

A recent study found that Jersey cows injected with serotonin produced more calcium-rich milk.
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Do you remember those ads about how happy cows make better milk? Turns out they were on to something. A recent study has shown that happy cows can produce milk with more calcium. This is accomplished by giving those cows serotonin shots.

Serotonin is a neurotransmitter connected to happiness, so it follows that happy cows have more serotonin, and that leads to more calcium in their blood or milk. Calcium is an important part of our diet, and in the West we get almost all of that from dairy products, so dairy farmers are under pressure to produce milk which is high in calcium. But it’s draining on the cows–so draining, in fact, that dairy cows often develop hypocalcaemia, a disease caused by insufficient calcium.

A recent study found that Holstein and Jersey cows, two of the most common dairy breeds, had improved calcium levels following serotonin treatments. But there’s a hitch: while the Jerseys had more calcium in their milk, the Holsteins had it in their bloodstream. So while happy Jerseys seem to be what we’re looking for, happy Holsteins aren’t any more useful to farmers.

Of course, this is only one study, and the first of its kind. The team who performed it is interested in doing more studies to figure out how to both keep cows from developing hypocalcaemia and help them produce more calcium-rich milk. And if serotonin can be used to prevent that disease, then it would go a long way toward keeping milk high in calcium. Since high calcium milk is in such demand, this would help farmers stay in business.

Since serotonin is something cows need in the first place, it’s unlikely that the introduction of serotonin treatments would have negative side effects. No additional hormones were needed to keep the cows with serotonin treatments producing milk as normal during the study.