31 March 2000

Red light can make cattle more active

CATTLE can distinguish between green and red light, but struggle to know the difference between green and blue light.

Research demonstrated that cattle become more active when stimulated by red light, which may be an evolutionary response caused by reddening of the cows vulva region during oestrus, says University of Cambridges Clive Phillips.

Red cape

He also said that this extra activity when cattle were exposed to the colour red potentially explained why bulls responded to the small red cape used by matadors to elicit their final charge in the dying stages of a bull fight.

But adopting a colour policy for housing would not benefit producers, said Dr Phillips, who added that the effects of colour on activity are short-lived. Once cattle have adjusted, their behavioural responses return to normal. &#42