We all learned it as kids: Old MacDonald has a farm and on that farm he has a cow that says 鈥渕oo.鈥� But why? Why do cows moo?
Whenever I鈥檓 out reporting in the field I can tell many ranchers have a powerful connection with their cattle 鈥� they can almost understand them. But researchers today are trying to figure out exactly what cows are saying.
I drove out to the beef research farm at the University of Missouri Columbia to meet cattle geneticist and ask him: What鈥檚 in a moo?
鈥淪o I'm definitely not an expert. I can't translate cow moos into English,鈥� he said. 鈥淏ut there are certain times when you can tell when the cattle are communicating with one another.鈥�
Here Are Some Reasons Why Cows Moo:
They're Trying To Find Their Friends
When cows change environments, like moving from one farm to another, they will moo to try to connect with their friends as they figure out their new surroundings. Decker said it鈥檚 like going to the school cafeteria after you鈥檝e just left a classroom. When you enter the cafeteria, you look for your friends. Cows often do the same thing when they get off the trailer that brought them to a new location. Some researchers believe moos can be distinctive, leading cows to connect with each other.
They Want To Make A Baby
These moos are the pick-up lines of the cattle world. Bulls and cows let each other know that they are ready to, in the words of a bovine Marvin Gaye, get it on.
They鈥檝e Lost Their Calf Or Their Mom
Researcher Monica Padilla de la Torre and her team looked at . When mama cows were separated from their babies, they made a higher pitched, louder call. When their babies were close by, the mothers gave a lower frequency call, suggesting that the higher frequency call is meant to alert calves that they are being missed.
The calves themselves gave a distinct moo when they wanted milk but couldn鈥檛 find their mothers.
De la Torre said the calves鈥� higher frequency moos and the older cow鈥檚 lower frequency moos were individually distinctive, suggesting moms and babies can actually recognize each other鈥檚 voices.
They鈥檙e Hungry
This call can be directed toward the farmer. The cattle wants to let him or her know that it鈥檚 time for some hay or grain.
They Need To Be Milked
Also, these moos can let the farmer know that it鈥檚 time for a helping hand.
They're Stressed Out
Maybe it鈥檚 too hot, they are caught in a fence or they are receiving vaccination shots. Decker says he鈥檚 noticed a higher pitched, more frequent moo when cows are dealing with these issues.
There is a flip side to this. One of my biggest problems as a radio reporter: cows not mooing when I鈥檓 out collecting audio for my stories. Cattle geneticist Jared Decker says that鈥檚 because happy cows don鈥檛 need to moo.
"It鈥檚 when something's out of the ordinary that they need to moo, right?" he said. "It's 'I'm hungry, farmer come feed me.' It's 'my baby's not near me, let me find my baby calf.' It's...'let's make a baby calf.'"
So whether they鈥檙e on the Missouri research farm or Old MacDonald鈥檚 farm, cows use moos to communicate. It turns out that that moo actually means something specific.
