The Department of Environment and Primary Industries (DPI) has dropped animal cruelty charges against the owner and an employee of a Gippsland abattoir.

The L.E. Giles Abattoir in Trafalgar was shut down for animal cruelty in 2011.

Animal rights group Animals Australia released a graphic video of pigs being slaughtered at the facility, claiming they had been killed inhumanely.

Last year, three abattoir employees received a 12-month behaviour bond after pleading guilty to animal cruelty charges.

Abattoir owner Colin Giles and employee David Rodwell were supposed to face charges over the incident at the Latrobe Valley Magistrates Court today.

But the DPI withdrew those charges and has refused to explain why.

The abattoir is still closed.