Modelling the impact of surplus pasture management techniques on production and profit in a pasture-based dairy system

Abstract

Three options for controlling surplus pasture on Northland dairy farms were modelled to determine the impact of each on production and operating profit. The three options were a) Light cut, fixed break size (LCFB): Paddock cut for silage as soon as surplus was identified. No effect on rotation length. b) Bulk cut, fixed break size (BCFB): Paddock closed until cover of 4000 kg dry matter (DM)/ha was reached then cut for silage. Rotation length was shortened. c) Bulk cut, variable break size (BCVB): Paddock closed until cover of 4000 kg DM/ha was reached then cut for silage. Rotation length was maintained thus reducing available grazing area. The hypothesis was that LCFB would translate into the most profitable option as pasture is being cut as soon as a genuine surplus is realised, optimising silage feed quality. Results showed LCFB to be $100/ha more profitable (operating profit) compared with BCFB and BCVB at only one of the three sites investigated (P