Tesco's institutional shareholders have been asked to lend support to a campaign by Hugh Fearnley-Whittingstall, the television chef, to improve the quality of life of chickens destined for supermarket freezer cabinets.

Mr Fearnley-Whittingstall has bought shares in Tesco and put forward a resolution for next week's annual meeting demanding the supermarket sign up to a higher level of RSPCA-supported chicken rearing.