A British zoo is facing closure and its owner prosecution after nearly 500 of its animals died of poor nutrition, cramped conditions and hypothermia over four years, it emerged Wednesday.

A damning report into the South Lakes Safari Zoo in Cumbria, northwest England, found that 486 animals had died in the past four years, putting most of the blame on its owner David Gill.

The zoo had over 1,600 animals in 2016.

Describing the conditions as "appalling", inspectors reported finding poor levels of veterinary care, cleanliness and pest control, as well as inadequate food.

"The conditions that these animals are being held in, is quite frankly appalling, and has led directly to the death of a number of them," they wrote in the report.

They recommended Gill be prosecuted under the Animal Welfare Act.

In 2016, 123 animals died including a West African giraffe which was euthanised a day after collapsing.

Post-mortem images raised concerns over nutrition.

A red kangaroo also died following a head trauma and six lion cubs were euthanised because the facility was not big enough to house them.

The report notes they were "healthy cubs and nothing wrong with them".

An African spurred tortoise was electrocuted on an electric fence, while a leopard tortoise died from cold.