Abstract #M213

Section: Production, Management and the Environment
Session: Production, Management & the Environment I
Format: Poster
Day/Time: Monday 7:30 AM–9:30 AM
Location: Exhibit Hall B

# M213
Economic and environmental impacts of revised amino acid recommendations on Canadian dairy farms.
S. Binggeli^*1, H. Lapierre², E. Charbonneau¹, D. Ouellet², D. Pellerin¹, ¹Université Laval, Quebec, QC, Canada, ²Agriculture and Agri-Food Canada, Sherbrooke, QC, Canada.

To ensure dairy farms sustainability, milk production must be cost effective and manure nitrogen (N) reduced. The main objective of this research was to evaluate the economic and environmental impacts of balancing dairy rations with a revised AA recommendations (RevRec) on Canadian dairy farms compared with NRC (2001). N-CyCLES, an Excel-based linear programming whole farm model, built using NRC (2001) recommendations, was updated with rev AA requierments (rqt; maintenance and lactation: Lapierre et al., 2016 (CNC); growth and gestation: NRC beef cattle, 2016; efficiency: Doepel et al., 2004 (JDS:1279) and supply (sup) (microbial CP: White et al., 2016 (JDS:7932); RUP: NRC, 2001). Data used for simulations were 2010–2014 means from DHI and management group databases for the Maritimes and Central Canada, and from Alberta agriculture websites for the Prairies. Essential AA rqt needed to be filled, with no constraint to cover metabolizable protein (MP) rqt. The results, as average (avg; Table 1), point to an economic gain when balancing rations with RevRec, compared with NRC (2001) MP and AA. The main change is a reduction in purchased feeds with a reduced need of rumen-protected AA to balance Lys and Met ratio. Farm N balance was lower Using RevRec, implying better used of N. An AA factorisation model seems to have global positive impacts on Canadian dairy farms and may help to reduce total CP sup and N excretion, assuming no impact on milk production. Table 1. Farm economic and environmental impacts of RevRec by region

	The Maritimes		Central Canada		The Prairies
	NRC 2001	RevRec	NRC 2001	RevRec	NRC 2001	RevRec
Milk/cow/y, kg	8,608		9,102		9,198
Net income, $/kg FPCM¹	0.079	0.102	0.195	0.212	0.210	0.229
N Balance, g/kg FPCM	12.20	11.90	13.74	12.36	13.82	12.98
MP avg rqt, g/cow/d	2,232	2,159	2,347	2,261	2,325	2,244
Lys avg rqt, g/cow/d	155	131	170	137	162	136
Met avg rqt, g/cow/d	53	43	58	45	55	44
His avg rqt, g/cow/d	—	43	—	44	—	44
MP avg sup, g/cow/d	2,232	2,040	2,440	2,203	2,325	2,085
Lys avg sup, g/cow/d	155	143	170	151	162	152
Met avg sup, g/cow/d	53	43	58	47	55	45
His avg sup, g/cow/d	—	43	—	48	—	44

¹Fat- and protein-corrected milk.

Key Words: dairy cow, amino acid, profitability