Former Manchester City striker Valeri Bojinov has travelled to England amid reports he will hold talks with West Ham.
Bothrwoyd signed a three year deal with the option of the club releasing him after two years.
And the 31-year-old, who joined the side on a free transfer in the summer of 2011,now becomes a free agent.
Bothroyd made 18 starts and 13 substitute appearances in all competitions since joining the club and scored five goals.
A statement on the club's official website read: "The club would like to thank Jay for his contribution and wish him all the best for the future."