The aim of this study was to evaluate the effects of including one or 2 sessions at grazing in milk production and dry mater intake (DMI) in mid lactation dairy cows. Twelve multiparous Holstein cows with 584 ± 71 kg BW, 193 ± 83 DIM, were allocated in a cuadruplicated 3 × 3 Latin square with 3 treatments: (1) fed a total mixed ration (TMR) during 22 h (TMR + 0h), (2) fed TMR during 14 h plus 8 h of grazing alfalfa in one session after afternoon milking (TMR + 8h), or (3) fed TMR during 14 h plus two 4-h grazing sessions after each milking (TMR+4+4h). Each experimental period consisted in 12 d of adaptation and 7 d of sampling. Intake of TMR (difference by offered and rejected) and lucerne (cutting 5% of the area pre and post-grazing) were individually measured during 5 d of each period. Milk production was individually recorded for 5 d, and samples were taken during 2 d in both daily milkings to analyze milk composition. The results are shown in Table 1. The intake of pasture was near 37% of the total DM consumed. This inclusion did not affect neither milk production nor composition. Fractionating the grazing session lead to higher intake of pasture. Table 1.

	TMR+0h	TMR+4+4h	TMR+8h	SEM	Treatment	Period
DMI (kg/d)
Lucerne	0c	8.18a	6.99b	0.266	0.0001	0.8265
TMR	23.26a	13.51b	12.43b	0.801	0.0001	0.0016
Total	23.26a	21.7ab	19.41b	0.839	0.0259	0.0059
Milk, kg/d	24.15	26.22	24.81	2.010	0.5835	0.2175
3.5% FCM, kg/d	27.42	28.69	27.59	2.153	0.7040	0.0179
Fat, kg/d	1.05	1.07	1.04	0.083	0.8508	0.0028
Fat, %	4.33	4.04	4.28	0.165	0.4225	0.6643
Protein, kg/d	0.89	0.91	0.88	0.065	0.8402	0.0320
Protein, %	3.77	3.54	3.57	0.105	0.2410	0.6877
Lactose, kg/d	1.16	1.26	1.20	0.100	0.6198	0.2922
Lactose, %	4.77	4.78	4.81	0.037	0.6678	0.1502
Feed efficiency1	1.24	1.35	1.42	0.121	0.3335	0.036

^a,b,cWithin a row, means with different superscripts are different (P <0.05). ¹3.5% FCM yield (kg/d)/DMI (kg/d).