He handled the eight minutes of therapy with ease.
Mrs Hennessy said the laser penetrated the tissue and stimulated the ''power cell within the cell'' to promote tissue growth.
Before the Dunedin clinic bought the laser, the nearest clinic for similar therapy was in Christchurch, she said.
Miss Bell said she had raised nearly $1800 for Demon by last night and started crying when someone donated $1000 yesterday.
''I had no idea it would go so big, so fast.''
She was overwhelmed by the generosity of Humanimals and the community.
Humanimals vet nurse Krystle Kelly said Demon would have laser therapy for five consecutive days.
The frequency of treatments after that would depend on the amount of new tissue growth on Demon's back.
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