Modelling of transport costs and logistics for on-farm milk segregation in New Zealand dairying
On-farm milk segregation to keep milk with high value properties separate from bulk milk will affect transport logistics. Separate milk collection, either as independent runs for different milk types, or storage of distinct milk types in the truck and trailer units, may increase the length and number of runs required. Two contrasting regions (representing the North and South Islands of New Zealand), with different farm sizes and roading networks were modelled, at two stages of lactation (peak and late) over 20 years. Thirty farms in each region were modelled with 0, 25, 50 and 100% of farms per region changing milk types over a transition period of up to 18 years. Genetic algorithm software was used to search for the order of the farm milk collection pick-ups which gave an optimal, least cost solution for milk collection for each prescribed set of inputs. Milk collection costs within scenario were variable over time depending on the amounts of the different milk types, increasing whenever another run was required, then decreasing over time as the milk load increased. Milk collection cost is small relative to milk income, with the status quo (SQ) cost for milk collection being less than NZ$9.61/kl for the North Island and NZ$13.53/kl for the South Island farm sets. The increased transport costs associated with collecting two milk types ranged from 4.5 to 22.0% more for the different scenarios. The extra cost to an average size North Island farm changing systems (25% farms changing), compared to an equivalent status quo farm, would be between NZ$307 and NZ$1244 per year. Fewer farms changing to differentiated milk production increased the costs per kilolitre of differentiated milk.
milk segregation collection costs milk transport scheduling