Japan's coast guard was trying to locate a livestock carrier reported missing in a storm with 43 crew and 5,800 cattle on board on Wednesday.
The coast guard said it had launched a search operation for the 8,400-dwt Gulf Livestock 1 (built 2002) in the East China Sea.
The ship had sent a distress call in the early hours of Wednesday about 185km west of Amami-Oshima Island.
The Maritime Self-Defence Force joined the operation with a surveillance aircraft.
It found what is thought to be a raft in the area later on Wednesday, the Defence Ministry said.
Filipinos make up bulk of crew
But the ministry did not confirm whether this was from the missing ship, or whether any seafarers were on it.
The crew consists of two Australians, 39 Filipinos including the master, and two New Zealanders.
The carrier left New Zealand on 14 August and was heading to China, where it was due to dock next Friday.
Bad weather from Typhoon Maysak was complicating the search, with strong winds and heavy rain in the area.
Technical manager Marconsult of Germany told TradeWinds it had no further information on the situation.
The vessel is listed as owned by Hijazi & Ghosheh Group of Jordan.
It was detained in Australia last May with seven deficiencies, but the only grounds for the detention was related to the ISM code.
The ship is entered with the West of England P&I club, according to Clarksons.
The livestock shipping industry has been under scrutiny from port state authorities after a series of accidents and wage issues in recent years.
In November, the 2,100-dwt Queen Hind (built 1980) sank with more than 14,000 sheep onboard off Romania. All 22 Syrian crew members onboard were rescued
