"Living within a group requires a moral code of behaviour... Most animals that live in communities exhibit similar moral codes to humans.
"Zoologists who have spent their professional lives studying animal behaviour, either by observation or by experiments to test their mental capacities, believe that many animals feel and think."
Joyce D'Silva, chief executive of CIWF, told BBC News Online: "The whole climate over whether to accept sentience has changed hugely in the last 15 years.
"It has huge implications for all the ways we use animals. It implies all farm animals are entitled to humane lives and deaths - and millions are denied them."
Dr Jackie Turner, research director of the CIWF Trust, told BBC News Online: "There's far more rationality and mental complexity in farm animals than we acknowledge.
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Innocent scientists?
Gil:
Are these scientists innocent too?