A report by an experienced veterinarian has prompted a court to delay sentencing for animal welfare law breaches relating to the death of 16 polo ponies on a Bass Strait ferry crossing.
The ponies were travelling from northwest Tasmania to Melbourne on the Spirit of Tasmania on the night of January 28, 2018 after competing in a polo tournament.
They were found dead when their transportation, a converted refrigeration trailer, was opened at Yarra Glen in regional Victoria at about 7.15am the next day.
Two horses, named Scarlet and Delilah, survived.
Spirit of Tasmania operator TT-Line was in October found guilty of breaching 29 animal welfare laws.
Former Australian polo captain Andrew Williams, who had driven the trailer, had earlier pleaded guilty to failing to ensure the horses were individually stalled and using a method of management reasonably likely to result in unreasonable and unjustifiable pain and suffering.
Sentencing for TT-Line and Williams, expected to occur in Burnie Magistrates Court on Wednesday, was delayed indefinitely because of "significant issues" raised in the report.
The report, by a European vet with some four decades' experience including in horse transportation, was submitted by Williams' lawyers.
Magistrate Leanne Topfer said it included evidence about the horses' efforts to escape the trailer that had not previously come before her and was relevant to sentencing.
The report said the horses' response to a lack of oxygen and increasing temperature in the trailer would have been "violent" and obvious to any observer as an emergency situation.
It said lowering the trailer's ramp would have corrected the oxygen deficit and temperature and saved the horses.
The report also said TT-Line's policy of not allowing passengers to access the area where the horses were being transported was significantly different to other ferry companies.
Ms Topfer adjourned the case until February 16 so TT-Line's lawyers can consider the report.
TT-Line had earlier pleaded not guilty to one charge of using a method of management reasonably likely to result in unreasonable and unjustifiable pain and suffering.
It had also pleaded not guilty to 28 counts of failing to ensure a horse was individually stalled.
In October, Ms Topfer ruled the company made no inquiries to ensure the horses were individually stalled, as per regulations, or ensure there was adequate ventilation.
She ruled the horses were exposed to the risk of acute heat stress and asphyxiation, and died from respiratory failure in a clearly inadequately ventilated transport.
TT-Line has appealed the guilty ruling in the Supreme Court of Tasmania.
