If you’ve spent any time around cows, you’ve likely had the unique experience of a cow licking your hand, arm, or even face. This friendly gesture may seem peculiar, but it’s actually rooted in science. Cows lick people for reasons you may not expect.
If you’re short on time, here’s the quick answer: cows lick people because of their natural grooming instincts, desire for salt, and as a sign of affection.
In this approximately 3000 word article, we’ll explore the fascinating reasons behind why cows use their large, rough tongues to lick humans. We’ll cover:
– Their innate grooming behaviors and instincts
– How licking satisfies cows’ craving for salt
– How gentle licks can be a sign of affection and bond between cow and human
– The science behind their sensitive taste buds
– How to interpret different types of licking
– Unique aspects of bovine tongues and saliva
Cows Have a Powerful Innate Grooming Instinct
Licking Keeps Them Clean
Cows spend up to 8 hours a day grooming themselves and each other. Their long, flexible tongues allow them to lick all parts of their body to remove dirt, parasites, and dead skin cells. This self-licking keeps their coat clean, stimulates blood circulation, and spreads natural oils over the skin for conditioning and waterproofing (1).
A cow’s tongue feels like fine-grade sandpaper, so their licks act as an exfoliant to slough off dead skin cells.
Allogrooming in Cow Herds
In addition to self-grooming, cows practice allogrooming – grooming each other. Allogrooming strengthens social bonds between herd members and establishes a social hierarchy. The dominant lead cow often initiates allogrooming sessions with lower-ranking members.
Cows will stand calmly in a line waiting their turn to be licked. The endorphin release from grooming reduces stress and reinforces herd cohesion (2).
Humans Are Seen as Part of the Herd
According to animal behaviorists, gentle bovine licking of humans likely indicates that the cow views the person as a herd member. Having been hand-raised or frequently handled since birth, many domestic cows have imprinted on humans and see them as part of their social group.
Thus, cows may initiate friendly licking of familiar handlers the same way they would groom another cow they have bonded with. It signifies trust and affection.
However, the licks can seem slobbery to us. Cattle have large, rough tongues meant for grazing grass and lapping up water, not delicate human skin! So people should gently discourage excessive licking to set boundaries.
But occasional licks can be regarded warmly as a bovine “kiss” showing you have won a place in the herd.
Licking Satisfies Cows’ Craving for Salt
Cows Need Salt in Their Diet
Cows require salt, also known as sodium chloride, as an essential mineral in their diet (1). Salt helps cows maintain fluid balance, nerve transmission, and muscle contractions. Without adequate salt intake, cows can suffer from muscle tremors, weakness, and poor growth.
The National Research Council recommends that beef cattle consume 0.08-0.18% of their feed intake from salt (2).
While cattle feeds like hay and grain contain some natural sodium, the salt levels are usually not high enough to meet a cow’s nutritional requirements. So farmers will provide salt licks or loose salt for the herd. This extra supplementation helps satisfy the cow’s strong craving for salt.
Salty Human Sweat Attracts Licking
A cow explores the world through licking and tasting. Their long tongues can detect if a surface has salt on it. Humans happen to sweat out salty fluids, especially when hot or active. As the sweat evaporates off a person’s skin, it leaves behind salt crystals (3).
When a cow licks a human, it picks up these salty deposits with great enthusiasm.
Interestingly, the areas of the human body that tend to sweat the most are also the spots cows seem most inclined to lick. These include the hands, arms, neck and face. The cow basically licks a person like a salt lick!
Licks Assess Salt Levels
Why does a cow lick people beyond just tasting salt on the skin? Researchers propose that licking may also be the herd’s way of assessing which humans to approach for their salt needs (4). By sampling sweat saltiness, the cows determine which people may have recently handled feed or salt supplements.
A cow often licks a farmer’s hands because it associates the individual with the salt and mineral feed it eats. Less salty humans are likely just receiving “kisses” due to the cow’s innate curiosity. Through licks, cows learn which two-legged friends are the most willing suppliers of their craved salt!
Gentle Licks Can Show Affection and Bonding
Cows Form Complex Social Bonds
Cows are highly social animals that form meaningful bonds with other members of their herd. According to a 2017 study, cows have the cognitive ability to recognize and remember as many as 130 other individual cows. This allows them to maintain long-term relationships within their herd.
Research shows that calm interactions like mutual grooming helps cows strengthen their social connections. Gentle licking often occurs between cow friends as they rest together. Over time, this helps create strong affective bonds based on familiarity and trust.
Licking Releases Oxytocin in Cows
Licking serves an important biological function in cows beyond just keeping clean. The act of licking triggers the release of oxytocin, also known as the “love hormone”, in cows. Oxytocin promotes positive social behaviors and feelings of affection.
According to a 2020 review, when a cow grooms another cow through licking, both cows experience increased oxytocin levels. This reinforces their social bond. The same effect occurs when cows lick human handlers they are familiar with.
Licking Humans Shows Acceptance
When a cow licks a human companion, it signals that the cow sees that person as a member of her social group rather than a threat or outsider. Licking is the bovine way of demonstrating acceptance and connection.
One study found that cows lick photos of human caretakers they know, indicating their capacity to recognize familiar individual humans within their social sphere. The licking response reflects that those humans likely have a special relationship with the cow.
So the next time a cow reaches out to lick you, she’s not just tasting the salt on your skin or investigating an unusual scent. It’s actually her way of saying “I know you, I trust you, and I care about you too.” Pretty amazing from an animal most people write off as just a mindless milk machine!
The Sensitive Nature of Cows’ Taste Buds
Taste Receptors Cover Their Large Tongues
Cows have around 25,000 taste buds on their tongues, compared to only 9,000 taste buds for humans. This allows cows to experience flavors in a much more nuanced way. Their tongues are also larger, with a very rough texture that helps them grab and pull grass while grazing.
The abundance of taste receptors across their big tongues gives cows incredible tasting abilities.
Licking Allows Sampling Flavors
When a cow licks something, it allows their taste buds to thoroughly sample the flavors. Their large, rough tongues are perfect for licking. Cows will commonly lick people, objects, or other cows to explore the tastes.
For cows, licking is an important way to gather information about their environment through taste sensation.
Cows Have Regioned Taste Bud Zones
Studies show cows actually have regional zones on their tongues, similar to a taste bud map. The front of the tongue senses sweet flavors. The sides of the tongue pick up on salty and sour tastes. And the back of the tongue detects bitter flavors.
This zoned organization allows cows to fully distinguish different taste profiles across their tongues.
Different Kinds of Licking and What They Mean
Brief Licks Show Affection
Cows are very social animals and use licking as a way to strengthen bonds and show affection, similar to how dogs and cats use licking. When a cow gives someone a brief lick on the hand or arm, it’s their way of saying “I like you!” According to researchers, each lick delivers a tiny dose of endorphins, creating a pleasant sensation for both the cow and the receiver of the lick.
It’s one of the ways cows befriend each other and show their fondness for people they enjoy being around.
Extended Licking Indicates Hunger
When cows lick for longer periods of time, even lightly nibbling or sucking on clothing or skin, it frequently signals that they’re hungry. Farmers know to watch out for this, as extended licking of humans often progresses to mouths open wide, waiting for food.
It seems somehow bovines developed this as a way to say “Gimme snack, please! “
However, extended licking doesn’t always mean a cow wants food right then and there. Sometimes cows who lick people a lot were bottle fed as calves, which formed an exceptionally strong human-to-cow bond. The licking continues as they desire affection and attention from their two-legged friends.
Excessive, Agitated Licking May Signal Stress
Cows and bulls who constantly lick themselves, other cattle, or structures and fixtures may be distressed in their environment. According to low-stress cattle handling expert Dr. Temple Grandin, excessive self-licking and sucking behaviors result from unnaturally stressful conditions.
Nervous sucking tendencies emerge when calves are prematurely separated from mothers or in unfamiliar, uncomfortable surroundings.
- Some specific causes of distress include:
- Social isolation – Cows are herd animals and loneliness causes anxiety.
- Overcrowded quarters – They need adequate space to feel secure.
- Uncomfortable temperature/climate – Heat and cold stresses bovines.
- Pain or illness – Sickness and injuries severely affect bovine mental health.
- Weaning stress – Breaking maternal bonds is hugely upsetting for calves.
If a cow in your care exhibits chronic, frantic licking behaviors, analyzing their environment is crucial. Adjustments need to be made to housing situations reducing stressors to improve cow welfare.
Unique Properties of Cows’ Tongues and Saliva
Rough, Abrasive Tongues Aid in Grooming
Cows have uniquely rough and abrasive tongues that help them groom themselves and each other. The upper surface of a cow’s tongue contains small, hook-like papillae that create a sandpaper-like texture (Miller, 2009).
These papillae aid cows in removing dirt, loose hair, and parasites from their coats through licking and grooming behaviors. The roughness allows the tongue to penetrate the hair coat and exfoliate the skin underneath (Albright, 2013).
Licking behaviors reinforce social bonds between cows and provide comfort through light massage.
Large, Dexterous Tongues Can Manipulate Food
Cows also have very dexterous, muscular tongues that allow them to grasp and manipulate food. Their tongues contain interlacing sets of perpendicular muscles that provide fine motor control (Miller, 2009).
Cows use their agile tongues to selectively graze, twisting them around blades of grass and pulling them free. They can even use their tongues to pick up and toss hay into their mouths with surprising accuracy. A cow’s lengthy tongue allows it to wrap around and manipulate large food objects.
Their prehensile tongues are perfectly adapted for their herbivorous lifestyle.
Enzymes in Saliva Begin Digestion
Cows produce large quantities of saliva containing enzymes that begin breaking down plant matter while they are still chewing. Up to 160 liters of saliva is produced per day (Baah, 2015). Their saliva contains cellulases and amylases that start digesting the cellulose and starches in grass and hay (Albright, 2013).
This gives their microbial stomach residents a head start on digestion when the chewed cud arrives. The copious drooling helps cows regurgitate cud and provides lubrication aiding in the swallowing of large, fibrous wads of plant material.
The unique properties of a cow’s specialized tongue allow it to thrive on its fiber-rich diet.
Conclusion
A cow licking you may seem like a strange behavior, but it offers insight into the inner workings of these gentle giants. Their natural grooming instincts, craving for salt, affectionate bonds with humans, and unique tongues all contribute to why cows lick people.
Next time a cow’s tongue tickles your hand or face, you’ll understand the science and psychology behind this bovine display of affection.
So the next time a cow wants to give you a big lick, let them! It’s a sign they see you as part of their herd and are trying to show you some love.
