More than 1,000 pigs have been burnt to death in a fire at a piggery at Mannum in South Australia's Murraylands, the RSPCA says.

Key points: The RSPCA said up to 1,300 pigs inside the shed were killed in the fire

The RSPCA said up to 1,300 pigs inside the shed were killed in the fire It is believed a pressure sprayer sparked the blaze, which has left a damage bill of $1 million

It is believed a pressure sprayer sparked the blaze, which has left a damage bill of $1 million The incident occurred shortly after hundreds of chickens were killed in a truck crash

Country Fire Service (CFS) crews were called to the Finniss Park Piggery on Piggery Road about 1:50pm, after the blaze broke out in a shed containing the animals.

Seven CFS fire trucks and 35 crews, as well as Metropolitan Fire Service personnel, have helped fight the fire east of Adelaide.

RSPCA and Primary Industries officials were later called to the scene, including two vets.

The RSPCA said between 1,200 and 1,300 pigs were killed in the blaze, and about 20 piglets which survived had to be euthanased because of burns.

The fire has left an estimated damage bill of $1 million.

The CFS said a pressure sprayer being refuelled is suspected to have sparked the blaze, but fire cause investigators are investigating.

The incident occurred just hours after a truck crash on the South Eastern Freeway killed about 1,000 chickens.

The B-double semi-trailer carrying the live chickens crashed past the Crafers turn-off about 3:30am, blocking the road for six hours.