THE cruel fate two alpacas met at a Caboolture school has not been deemed serious enough, despite a robust Attorney-General appeal, to send one of the young men responsible to jail.

Wayne Charles Hartwig, 20, and his 16-year-old co-offender used rocks, a hose and a metal pole to repeatedly bash the animals for about 30 minutes in the Caboolture High School grounds late at night while drunk.

One alpaca died and other was so badly injured it had to be euthanised.

Hartwig was jailed for six months for the brutal bashing but was released on immediate parole.

Justice John Muir, in a Court of Appeal decision handed down on Friday, did record the seriousness of Hartwig's actions.

"The animals were public property used in the education of children, which was no doubt in part directed to inculcating respect for animals and awareness of the need to safeguard their welfare," he said.

"The animals were destroyed and children were exposed to emotional upset and conduct diametrically opposed to the principles and attitudes which their education was seeking to instil.

"... the offending affected many more people than would be affected by the killing of a domestic pet."

But the appeal court instead opted to suspend the sentence for 18 months instead of allowing Hartwig's release on immediate parole.

Justice Muir said the consequence of the change, unlike the original sentence, would mean if Hartwig reoffended any time in the next 18 months, he must serve the six-month term.

Hartwig must also complete 18 months of probation and submit to psychiatric or psychological treatment.

Attorney-General Jarrod Bleijie said although his appeal was successful, he questioned whether suspended sentences had relevance when an offender was allowed to walk free without receiving actual jail time.

"Should Hartwig commit another offence, he will be brought back before the court to be resentenced," he said.

"Given the community's expectation of the justice system, this government is reviewing the sentencing options available to judges.

"This government considers animal cruelty as a serious crime and we will legislate to ensure those who commit offences such as these will go to jail, full stop."