washington

The US government is facing a renewed call to extend legal protection to some 20 million laboratory mice and rats not covered by current law.

The Animal Welfare Act, which is administered by the US Department of Agriculture (USDA), covers animals such as dogs, cats, rabbits, guinea pigs and non-human primates but, under an exemption approved in 1976, does not apply to mice, rats and birds.

Mice and rats are estimated to make up at least 85 per cent of US research animals. “These animals deserve the same protection as others used in experiments,” said Tina Nelson, the executive director of the American Anti-Vivisection Society (AAVS). The society, a sharp critic of the treatment of laboratory animals, announced last week that it was petitioning the USDA. The move follows a previous unsuccessful attempt by other groups in 1989. “These animals are not afforded even minimal coverage by the Act,” said Nelson.

Nelson argues that this has removed incentives for scientists to seek alternatives. She points, for example, to the “ascites method” used to produce monoclonal antibodies, in which tumours are grown in the abdomens of mice and the antibodies generated are tapped by syringe.

The act allows for unannounced laboratory inspections by USDA, and requires researchers to report annually on the numbers of laboratory animals in their care. Also, institutional committees that review experimental protocols must require investigators to consider non-animal alternatives.

The USDA has 180 days to respond to the petition. If it denies it, Nelson says, the AAVS will sue the government. The 1989 petition, which was similar to the current one, was denied by USDA. The petitioners sued, but a court found that they had not demonstrated sufficient legal standing or injury to the rodents to justify the suit. The AAVS says its petition addresses those weaknesses.

Scientific groups, although not opposing the extension of the law in principle, say that the success of the petition could cripple the resource-starved USDA inspectorate, particularly as it would have to inspect small institutions such as community colleges and even high schools that use only rodents in their laboratories. “It would destroy USDA's already limited ability to meet its inspection mandates,” says Tony Mazzaschi, a research policy analyst at the Association of American Medical Colleges.

Ralph Dell, director of the Institute for Laboratory Animal Research — a division of the National Research Council — estimates that the increased workload would require a doubling of USDA's $9.2 million budget for enforcing the act.

Others argue that rodents are already cared for scrupulously. “The personnel at research facilities don't need a federal law in order to be motivated to care for their animals well. Good science demands it,” says Barbara Rich, executive vice-president of the National Association for Biomedical Research.

The scientists also claim that extension of the law would make little difference to the vast majority of rodent-using institutions, which are already governed by other federal policies that cover rodent use.

For instance, scientists funded by the Public Health Service — including all those on National Institutes of Health grants — are covered by a policy on the humane use of l aboratory animals that applies to all vertebrates. This policy does not, however, have the force of law, and it requires neither reporting of numbers nor surprise laboratory inspections.