Optimizing concurrently dairy farm profitability and environmental performance

Abstract Text:

The objective of this analysis was to assess economic and environmental impacts of a dairy farm milk production using the Integrated Farm System Model (IFSM, version 4.0, University Park, Pennsylvania). The IFSM was applied to integrate crop growth, feed storage, machinery usage, and herd management to simulate the highest possible milk production with the available on-farm resources and purchased feed. A representative Wisconsin dairy farm system was defined as a typical farm with 100 milking cows, 247 acres of cropland. Farm performance was then simulated using 25 yr of daily weather data (1986-2010). A sensitivity analysis was conducted by increasing the input target milk production starting at 9,837 kg/cow per yr. The fat-protein-corrected milk production (FPCM) increased linearly as the target milk production was increased to 10,457 kg/cow per yr. Followed, the FPCM increased non-linearly (at a decreasing rate) until the target milk production was increased to 10,980 kg/cow per yr. Thereafter, FPCM remained flat regardless of higher target milk production input. The per-kg FPCM net return ($/kg FPCM) showed a similar trend increasing from $4.08 ± 2.32 to 6.20 ± 2.19, and then to $6.78 ± 2.18, respectively. Given the farm carbon footprint (kg CO₂eq/kg FPCM) as the result of dividing the net greenhouse gas emission (including methane, nitrous oxide, and carbon dioxide) by the FPCM, it decreased from 0.69 ± 0.04, to 0.67 ± 0.04, and then to 0.65 ± 0.04, respectively, as the FPCM and the net return increased. We concluded that increasing productivity using only farm available resources would elevate the net return and decrease carbon footprint at the same time. Further research is required to explore management strategies that determine increased productivity within farm-specific conditions.

Input target milk production (kg/cow per yr)	Simulated actual milk production (kg/cow per yr)	Fat-protein-corrected milk production (FPCM; kg/cow per yr)	Net return per kg of FPCM (FPCM; $/kg FPCM )	Carbon footprint (kg CO2 eq/kg FPCM)
9,834	9,834 ± 0.00	9,079 ± 0.00	4.80 ± 2.32	0.69 ± 0.04
10,457	10,455 ± 9.54	9,652 ± 9.54	6.20 ± 2.19	0.67 ± 0.04
10,980	10,748 ± 96.82	9,922 ± 89.54	6.78 ± 2.18	0.65 ± 0.04
11,457	10,746 ± 87.27	9,921 ± 80.45	6.78 ± 2.15	0.65 ± 0.04

Keywords:

whole-farm simulation model, farm profit, greenhouse gas emission