Scrappy the dog was choked and doped as he tried to save his feathered friends from burglars.
The border collie was guarding his mistress's pet shop, which sells exotic birds worth hundreds of pounds.
The offenders grabbed a rope tied to Scrappy's collar and yanked him to a door, jamming his head and neck against it.
They then injected him with a knock-out drug and waited for it to take effect.
The thieves made off with three African grey parrots, a white cockatoo called Chalky and a yellow-fronted Amazon parrot called Oscar, who has a missing claw on his left foot.
Rewards are being offered for their safe return and arrest of the thieves but shop owner Sharon Hurrell said the birds were worth more than just money.
She said: "I've been close to tears. I've had the birds for a long time and raised some from chicks. They are part of the family.
"I'm just thankful Scrappy is alive. I was heartbroken when I saw what they did to him. His neck is swollen where he was almost choked to death and there's a lump where they injected him."
Scrappy was being seen by a vet last night for a blood test to determine which drug was used.
The thieves broke in at Elite Pets in Yapton Road, Barnham, near Bognor, during the early hours of New Year's Eve.
Professionals stealing to order are thought to be behind the raid and there have been others in Sussex recently.
A breeder in Henfield and another in Haywards Heath had birds stolen.
One Sussex nursery paid a ransom to get their rare birds back.
A £1,000 reward is being offered by Mrs Hurrell's husband Clive and another substantial reward is being offered by the National Theft Register for exotic animals (NTR), which acts for parrot breeders.
NTR co-ordinator John Hayward said: "These offences may be linked to others around the South-East.
"Parrots are particularly intelligent and sensitive. They would suffer trauma by being taken like this and the sooner we get them back the better."
He said exotic birds were being stolen to order and could end up anywhere in the UK or Europe.
All the birds taken from Barnham can be identified by their markings, rings or microchips.
Bird cages, choke chains and dog leads were also taken.
Anyone with information on the birds or who may have been offered them should contact PC Stuart Hickman at Littlehampton police station on 0845 6070999.
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