The former captain of Australia's polo team says he could tell something was wrong in the back of the truck he was driving before discovering 16 ponies "cold dead" on the trip from Tasmania to New South Wales.
Andrew Williams has described the events leading up to him finding the dead animals and two "fighting to survive" within an hour of disembarking the Spirit Of Tasmania ferry in Melbourne on January 29 after competing at the Barnbougle Polo club event earlier that month.
Tasmania's Department of Primary Industries, Parks, Water and the Environment has launched an investigation into the deaths.
A probe by the Australian Maritime Safety Authority found Spirit Of Tasmania operator TT-Line "complied with AMSA requirements relating to the carriage of livestock".
"I have done this trip 11 times in the same truck, but I knew something was wrong as I drove through the city of Melbourne a short time after disembarking. So I rang my other truck and asked if his load was travelling well," Williams said in a statement.
"My head groom said his horses couldn't wait to get off his truck. I knew then that something was potentially wrong, as mine was not indicating the usual activity. I then arrived in Yarra Glen at a friend's property. It was my worst nightmare.
"Within an hour of leaving the boat, I had 16 horses that were cold dead and two fighting to survive.
"I just went into survival mode for the surviving two, and after offloading them in Yarra Glen, I was on the road with the 16 dead polo ponies to Wagga Equine Hospital."
The Wagga facility was conducting necropsies, Williams said, adding the results were "not yet known".
The ABC understands six of the ponies were owned by John Kahlbetzer, founder of Twynams Agricultural Group and one of Australia's richest men.
On the website of his Willo Polo club, Williams is listed as NSW Polo Association's senior coach and junior development squad coach.
He is also listed as being on the national selection committee for the Australian Polo Federation.
Williams is a business partner with landowner Justin Couper at the Barnbougle Polo club, which was established in 2015 near Bridport, in Tasmania's north-east.
Mr Couper described the pony deaths as potentially "career breaking for Andrew".
"But he is tough, just how tough we will wait and see."
Heatwave conditions for journey home
On the days between the polo tournament in north-east Tasmania and the voyage back to the mainland, Tasmania was in the grip of heatwave conditions, with Hobart notching up the hottest January minimum temperature on record.
"It was a warm night," Williams said.
"What I know is I saw 18 healthy horses on my truck just before departure in Tasmania, and an hour after leaving the boat in Melbourne I discovered 16 of them were dead and cold," Williams said.
"I am a farmer, a polo player and a breeder of ponies. They are the reason I can feed my family. To have that taken away is gut-wrenching.
"It is with the legal team now and hopefully they will receive the answers I deserve."
Williams said he had contributed much to the sport's growth in Tasmania and needed "answers".
"No-one should go through what I have recently gone through. I am just trying to stay busy, but it's there, and I can't see it going away until we have some answers," he said.