At least 58 cattle have died on a cargo vessel docked off the Turkish coast that authorities have refused to let enter port, the Animal Welfare Foundation (AWF) said Friday.
The group said that court documents had revealed "alarming" conditions that are worsening on the Spiridon II, which brought some 2,900 cattle, mainly pregnant cows, from Uruguay.
It said that 58 animals had died during the crossing from Uruguay, and at least 40 cows had given birth during the journey.
AWF said in a statement that it was likely most of the newborns had died as they were kept in an overcrowded enclosure.
The group said it had appealed to Turkish authorities to let the animals be brought ashore but had not received a response. The ship has been off the western port of Bandirma since October 21, having left Uruguay on September 19.
Turkish authorities say there are discrepancies in the animals' health certificates.
Other NGOs have also complained about the case, and the export company is taking legal action. Turkish media have highlighted a foul odour around the ship.