Two animals have been stabbed in what police called "an apparently motiveless attack" in the village of Cucklington.
A border collie dog and a Welsh show pony sustained deep stab wounds after the attack which took place on a farm some time overnight on Saturday, 1 November and 2 November.
The dog was stabbed in the chest and required emergency treatment from a vet, but is now recovering.
The pony was stabbed in the shoulder.
Both animals received single stab wounds which were around five inches deep.
A police spokesman said: "If emergency treatment had not been carried out by vets both animals could have died from the injuries."