A program to assess the efficiencies of sheep-meat production
systems: A teaching aid
R.W. Purchas
Institute of Food, Nutrition & Human Health, Massey University,
Palmerston North
Proceedings of the New Zealand Society of Animal Production.
2000 60: 135-138
A computer program written in Visual Basic within a spreadsheet
was developed to illustrate how the efficiency of a sheep-meat
production system varies when changes are made in any or all of 32
variables. System performance is expressed in monetary terms as either
the efficiency (E) in dollars returns per dollar cost (with a break-even
value of 1) or as a profit. Costs and returns for ewes, rams and lambs
are taken into account, and all are expressed on a per ewe per year
basis. A single per kilogram price for mutton is used, but for lambs,
the proportion falling into various classes at any carcass weight is
calculated using a specified GR/carcass weight relationship in a
separate simulation program. Relationships within the E-program are
based on published data, such as those in lamb feed requirement tables.
This program has proved useful as an aid to evaluating some
repercussions of making various combinations of changes to sheep-meat
production systems.
Keywords: NZSAPAB;
lamb growth; spreadsheet model; meat production; system efficiency
Last Updated 12-07-2000
