It is believed the harmful liquid was poured over the dog in the Burren Meadow area of Newcastle between 7pm and 9pm last Thursday, September 18.
Alliance Councillor Patrick Clarke said: “I am totally appalled by the recent alleged case of animal cruelty in Newcastle, when a defenceless dog was subjected to a harmful liquid being poured over the animal resulting in burns to the dog’s skin.
“The incident is an absolute despicable and sickening act and form of animal cruelty which I totally and utterly condemn.
“Anyone who would carry out such a cruel and criminal act causing injuries to the dog has no regard for the animal’s welfare and needs to be brought before the courts and I would appeal to anyone with information to contact the PSNI on the non-emergency number 101.”