The US government has ended its 30-year practice of breeding and then killing lab kittens used as vessels to harvest parasites.

Over 3,000 kittens were bred by the US Department of Agriculture (USDA) for the sole reason of being infected with a parasite called Toxoplasma gondii (T.gondii,) activists from the White Coat Project said in May 2018.

Since then, a campaign from activists and politicians has gained momentum, resulting in the so-called Kitten Act being introduced to the US House of Representatives in March 19.

The act seeks to prohibit the USDA from using kittens in painful experiments.

According to activists, kittens were fed meat infected with the parasite and the eggs, which would then grow inside them.

The parasites were harvested from the kittens' faeces and used in further research. The kittens were killed by incineration when they got to three months old.

On Tuesday the DoA's Agricultural Research Service (ARS) released a statement saying: "The use of cats as part of any research protocol in any ARS laboratory has been discontinued and will not be reinstated."

The department said they used cats as they were the only lifeform in which T. gondii could thrive, complete its life cycle, and produce eggs.

The White Coat Project report said an ARS lab in Beltsville, Maryland, was a center for the program. They say between 1982 and 2019, 3,000 kittens were bred for the sole purpose of infection.

The kittens are healthy after they complete the research but are killed anyway, the USDA said. They said: "USDA does not seek adoptions of these cats because of the risk the cats could pose to their adoptive families."

The USDA said it owns 14 kittens which were part of the program but not yet infected. They will be put up for adoption by USDA staff.

The infection Toxoplasmosis, caused by T.gondii, is considered the second leading cause of foodborne-related deaths in the US.

This article was originally published by Business Insider.

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