Question:
Do the calculation for displacement yourself.
The feed intake capacity of a cow is 16 SV units/day. Fresh grass has an SV of 0.9 per kg dry matter and 1,030 FUM. Concentrate feed has an SV of 0.4 per kg of dry matter and 900 FUM. The cow requirement is 19,000 FUM.
Calculate amounts of roughage and concentrates given to the cow:
Answer:
FUM requirement: (grass × 1030) + (concentrate × 900) = 19,000
SV requirement: (grass × 0.9) + (concentrate × 0.4) = 16
From FUM:
Grass = (19,000 - (concentrate × 900)) / 1030
Grass = 18.4 - (concentrates × 0.87)
Substitute into SV:
16 = ((18.4 - (concentrates × 0.87)) × 0.9) + (concentrates × 0.4)
16 = 16.6 - (concentrates × 0.38)
concentrates = 1.6 kg DM
Grass = 18.4 - (1.6 × 0.87) = 17.1 kg DM