Orana Wildlife Park says it told MPI about all its animal deaths, after claims of poor welfare standards.
More than 20 current and former staff have detailed multiple animal deaths to 1News, some which went unreported.
MPI is doing a rapid assessment of the zoo's conditions - due back tomorrow - but say it wasn't told about any deaths.
Board member Ken Hughey says all deaths were notified, and they've taken measures since.
"Those sort of deaths, often with the benefit of hindsight, may be preventable. We absolutely accept that, and we learn as we go - we are a learning-based organisation."
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