The boss of Christchurch's Orana Wildlife Park is pushing back on poor animal welfare claims.

More than 20 current and former staff have detailed multiple animal deaths to 1News.

Newstalk ZB's Blake Benny says an MPI report on the zoo's conditions is expected by tomorrow, with an investigation also underway into the death of an antelope.

It confirmsa the zoo was meeting requirements in December -- with appropriate staffing and no animal welfare issues identified.

Orana Wildlife Trust Chief Executive, Lynn Anderson told The Press it takes all matters raised seriously.

She says it can provide evidence discounting the majority of claims.