Silver Fern Farms says it will no longer accept spring-born ram lambs after 31 March, because the meat they produce does not match its new standards.
Citing reasons of quality and texture, the meat co-operative says any ram lambs received after 31 March each year will now be processed, and paid for, as mutton.
Once ram lambs reach a certain age, the taste and eating quality of the meat is not as good, according to chief executive Keith Cooper.
The meat is intended for export.
