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The objectives were to study the ef- fects of feeding rolled flaxseed (FLX) to early-lactation dairy cows on milk yield, milk components, and milk fatty acid profiles as well as on measures of cow re- production. Lactating Holstein cows, on 3 commercial dairies, were fed either an early-lactation ration (CON) or a ration that was similar in protein, energy, and fat content but that included FLX (0.85 kg of DM/ cow per day). Within each dairy, cows were allocated alternately to breeding pens upon leaving the fresh pen (approximately 10 ± 5 d postpartum). Pens (n = 4 to 5 pens/dairy) were randomized to treatment (n = 2 to 3 pens/treatment per dairy). Pen (CON, n = 6; FLX, n = 7) was considered the experimental unit and data were analyzed as a split plot with pen as the whole-plot error term. Cows fed FLX had greater (P ≤ 0.06) pro- portions of cis-9, trans-11 C18:2, C18:3n-3, and C20:0 fatty acids in milk fat and a lesser (P = 0.03) propor- tion of C20:3n-6 fatty acid when compared with cows fed the CON diet. Treatment did not affect (P ≥ 0.24) milk yield, milk protein, protein yield, milk fat, or milk fat yield. No interactions (P ≥ 0.52) were found be- tween treatment and season of the year or parity, or be- tween treatment and days open, pregnancies per AI at first or second service, or pregnancy loss. In conclusion, feeding FLX at 0.85 kg/cow per day (DM basis) altered the fatty acid profile of milk, but milk yield, milk com- position, and reproductive performance of dairy cows were not affected.