Signs of Heat Detection

Oestrus is defined as the period of maximal sexual activity. The average duration is thought to be only 8 hours for the modern dairy cow, however it can range from 2-30hours. There are various signs and different animals will express these to varying degrees:

Increased restlessness & activity

Decreased feed intake and milk yield

Bellowing when isolated

Slight increase (0.1°) in body temperature

Clear vulval mucus (bulling string)

Rub marks over the tail head

Mounting other cows, particularly from head on

Standing to be mounted