Figuring out when your cows and heifers are in heat is a vital part of any dairy or suckler operation.

Cows tend go back into heat about two months after calving. The average duration of standing heat is 15 to 18 hours, but heat duration may vary from 8 to 30 hours among cows.

Bull mounting a dairy cow who is in standing heat

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While it isn’t always obvious when they’re in estrus (heat), there are a few signs you can look out for to help.


When your cow or heifer is in heat, it is common for her to be restless, and lowering her head as if looking for her calf.

She sometimes wanders away from the herd on her own.

cow wandering off on her own - signs of heat in cattle


Estrus cows can display unusual urination patterns; some urinate only a little at a time and sniff the air.

Body language

Cows in heat carry themselves differently than they do in the rest of their cycle. Very often, their eyes carry a wild expression, and they flick their ears more than normal.

Sniffing Signs a cow is in heat estrus moocall heat


This is the most obvious sign of heat in cows and heifers.

Often times, a cow in heat will try to mount other cows, and allow them to mount her.

Estrus cows have been known to lick other cows too.

cow mounting another cow symptom of heat estrus

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Vulva mucous

Estrus cows often have swollen vulvas, and occasionally mucous hangs from it.

The tail is sometimes slightly lifted as it hangs next to the vulva.

vulva discharge mucous signs of heat cow heifer

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Moocall HEAT

While these are all common signs of heat, many heats go undetected because cows and heifers don’t always display them.

If you want to guarantee an astonishingly accurate heat detection rate then look no further.

Moocall HEAT collar for heat detection in stock or vasectomised bulls

Moocall HEAT is our brand new heat detection system on dairy or suckler operations. It comes in two parts; Moocall RFID tags to be worn by the cows and heifers, and a collar designed to be worn by a stock or teaser bull.

We have decided to use nature to our advantage and monitor the bull’s behaviour and his interaction with cows.

It catches these easy-to-miss silent heats that don’t have any visual symptoms.

Learn more about it here: