A Perth man has been fined $6000 and banned from owning an animal for five years after a vet saw his American pit bull terrier-cross puppy Caesar weighed only a third of what he should.

When Port Kennedy man Christopher Paul Hansen took the badly emaciated 10-month-old to the vet, the pup weighed only 10.5kg but should have weighed 25-30kg.

He also had a severe skin infection affecting 90 per cent of his body.

Hansen said the puppy was not eating and was unsure when it last ate.

Hanson also knew the puppy had a skin mite, for which he had been unable to get treatment because he was short of money.

Blood tests also confirmed the puppy was dehydrated and had sepsis along with other conditions.

Despite Caesar receiving extensive veterinary treatment over a period of six days, his condition continued to deteriorate, he lapsed into a coma and was euthanased on humane grounds.

In Rockingham Magistrates Court this week, Hansen was found guilty of two counts of animal cruelty, failure to provide proper and sufficient food and failure to take steps to alleviate harm.

- AAP

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