The RSPCA euthanased more than 4800 dogs in NSW last financial year, about 40 per cent of dogs brought in. More than 60 per cent of those were euthanased due to "behavioural" problems.

The overall rate of dogs killed far exceeds some council pounds that work with "no-kill" animal rescue groups, such as Muswellbrook (3.7 per cent) and Wyong (12 per cent).

Late yesterday, the RSPCA released to the Herald a copy of its behavioural assessments, otherwise known as "temperament tests", after initially refusing the request on confidentiality grounds.

It showed dogs are scored negatively for behaviour such as barking, trembling and jumping. Those that accrue more than 100 points are deemed "unsuitable for adoption".

An RSPCA spokeswoman said the document was used as a "guide", and options such as rehabilitation, behaviour modification and foster care were investigated before euthanasia.

But the Principal of Lawyers for Companion Animals, Anne Greenaway, said so-called aggressive behaviours were often exhibited by animals that were "terrified".

"It's a lack of proactive measures to try and save animals, rather than put in the monumental effort that rescue groups do, the RSPCA appears to find it easier to kill [them]," Ms Greenaway said.

She believes the RSPCA was ''threatened'' by other animal welfare groups with which it competed for funding and donations, and often would not work in collaboration with them.

She described its approach to animal management and re-homing as "lazy and apathetic compared to other groups", citing the low numbers of cats and dogs advertised for adoption on its website.

Several animal rescue groups contacted by the Herald reported the RSPCA had not responded to offers to release dogs into their care for potential re-homing. Nathan Barnes, a former RSPCA employee and animal behaviour expert who claimed to have helped devise the behavioural test, said it was used incorrectly.

"The idea of the temperament test was not to fail the dog; it was to discover what the actual true behaviour is,'' he said. ''After the results of the test, you need to carry out rehabilitation if it's required, which is not happening, then reassess the dog."

Mr Barnes said the tests were often carried out under the wrong conditions, such as assessing a dog before it had adjusted to the pound environment.

The RSPCA NSW chief executive, Steve Coleman, said a dog that displays "overt aggression" towards a person or other animal "will likely be deemed unsuitable for placement".

He rejected claims the RSPCA was unwilling to collaborate with other animal welfare organisations, adding that "discussions have been undertaken, and continue to be undertaken, with a number of community-based rescue groups".

He said the organisation relied on shelter staff and volunteers to photograph animals available for adoption, and staff often had more pressing duties.

He denied that behaviour assessments were conducted while animals were still settling in, and said rehabilitation was considered in light of the animal's background, behaviour in the shelter and "available rehabilitation opportunities".

The RSPCA also helped dogs find a new home through a state-wide foster care network and other programs, he said.