Devices for oestrus detection

An oestrus detection device comprising an indicator carrier of flexible material adapted for attachment to the back of an animal between its hip-bones, an area of flexible material attached to the carrier to form a sleeve which widens toward one end opening, a pair of internal shoulders at the wider end opening, an indicator detachably mounted to the carrier and made of a flexible coloured material having a sachet of differently-coloured flowable material connected through a fine orifice to at least one channel, side wings incorporated with said indicator which cooperates with the internal side shoulders of the sleeve to prevent the indicator sliding from the sleeve, the construction and arrangement being such that when the indicator-mounted carrier is mounted on a cow or other female animal and mating technique by a second animal is made, pressure applied by the second animal upon the sachet will force the differently-coloured material to flow along the channel or channels of the indicator which extends through the sleeve from its narrower opening and beyond the carrier for observation.