Ryeland lamb. The Ryeland is a Downs type sheep originating from Herefordshire in England and was introduced into Australia in 1919. It was one of the breeds used to introduce the poll gene to the Dorset breed in the development of the Poll Dorset. The Ryeland is a hornless, prime lamb producer. It carries a fine Downs type wool, and is well regarded as a fertile, heavy milking breed specializing in the production of prime lambs.