The District Court found no exceptional circumstances, nor did the High Court on appeal.
To the Court of Appeal Mr McClintock claimed Mr Rean kicked Scoobie, provoking him, and only suffered a nip that did not need medical treatment. He said the dog acted in "self-defence".
He said the dog was of good temperament, devoted to children and denied Scoobie was a dangerous dog.
"And he seeks mercy, saying that he is 76 and in ill health and Scoobie means everything to him," the judgment said.
However, the court concluded Scoobie attacked without provocation and there was no excuse for not having him secured. It found Mr Rean did need medical attention.
"It seems plain that Scoobie has an over-developed territorial instinct. And while we accept that he is a much-loved family pet whose fate may exacerbate Mr McClintock's health difficulties, that is not an exceptional circumstances either."