The killing of thousands of animals which have been bred for research, including 40,000 in a year by one New Zealand university, has been questioned as part of Government reforms of animal welfare rules.
A Parliamentary select committee was told yesterday that scientific institutions were over-breeding animals, in particular rats and mice, and many were being disposed of without even being used in testing.
The National Animal Ethics Advisory Committee, an independent advisor to the Ministry for Primary Industries, said that there was no pressure to reduce the number of animals which were bred.
Chair Virginia William said: "They often breed a lot more than are ever needed and these animals are just killed. The one estimate we got from an estimate was something over 40,000 animals were just bred and never used."
She added: "We think it's quite high. At the moment, there's no ethical oversight of that.
And if there was some oversight then it might put pressure on them not to over-breed quite so much."
At present, there was only regulatory oversight for animals which were manipulated or experimented on while they were alive.
The Animal Welfare Amendment Bill which the committee was considering would allow Government to require institutions to report the killing of animals that were bred, but not used, for research.
Dr Williams said current rules also did not calculate how many animals were experimented on after being killed - such as having fresh tissue removed.
There was little data on this use of animals, but a survey found one large university killed then carried out testing on 3000 animals a year.
Around 300,000 animals were used in animal testing each year by universities, most of them rodents but also cattle, chickens and sheep.
• New offence for wilful ill-treatment or reckless treatment of wild animals, with maximum sentence of 5 years' jail or $100,000 fine
• Killing of an animal for research must have approval of an ethics committee
•New powers for Government to ban painful surgical procedures, or to require a university to report how many animals it bred and did not use for testing.