A company that breeds animals for medical testing has been fined a record $35m (£27m) after 4,000 beagles were rescued from its facility in Virginia in 2022.

The fine against Envigo RMS LLC for animal cruelty is the largest fine ever issued under the Animal Welfare Act, according to the US Department of Justice (DoJ).

“Envigo promoted a business culture that prioritized profit and convenience over following the law,” Christopher Kavanaugh, the US attorney for the Western District of Virginia, said in a statement.

“This callous approach led to dire consequences: the inhumane treatment of animals and the contamination of our waterway,” he said.

Envigo’s parent company, Inotiv, has agreed to pay the record eight-figure settlement. It has also agreed to not breed dogs for the next five years.

By committing the crimes it was charged with “and by not making the necessary infrastructure upgrades and hiring the requisite staff, we fell short of our standards for animal and environmental welfare and apologize to the public for the harm caused by our conduct,” Inotiv said in a statement on it’s website on Monday.

The breeding facility in Cumberland, owned by Envigo RMS, was sued in May by the US Department of Justice. The federal agency accused it of multiple acts of animal cruelty.

Inspectors found some dogs were being killed instead of receiving basic veterinary care for conditions that can be easily treated. The animals were also being fed with food that contained maggots, mould and faeces, while some nursing mothers were not given anything to eat at all.

The rescue of the 4,000 dogs from the facility in August 2022 led to a nationwide effort by animal shelters to find the dogs new owners in the US.

The justice department said on Monday that Envigo had admitted that it had “conspired to knowingly violate the Animal Welfare Act by failing to provide, among other things, adequate veterinary care, adequate staffing and safe living conditions for dogs housed at the Cumberland County facility”.

The breeder’s sister company, Envigo Global Services Inc, has also admitted to breaking the Clean Water Act by not properly treating wastewater, adversely affecting the dogs’ health and contaminating the environment.

The agreement calls for the company to pay $22m to the US government, as well as pay approximately $1.1m to the Virginia Animal Fighting Task Force and approximately $1.9m to the Humane Society of the United States for their help rescuing the beagles.

The deal will be formally approved by a judge on 7 October.