To examine the effects of chemical treatments of whole barley grain on milk production and components of dairy cows, 9 multiparous cows (131.44 ± 9.32 DIM, 30.2 ± 5.14 kg daily milk yield) fed a total mixed ration supplemented with ground barley grain (control), or whole barley grain treated with sodium hydroxide (10%) and dried in different periods including: dried immediately (0h) or after 48h storage in plastic bags (48h). Sodium hydroxide was used at the level of 3.5% (DM) of barley grain. Each period lasted 3 week; experimental analyses were restricted to the last week of each period. Diets were formulated according to NRC 2001. Cows were housed in tie stalls and fed the TMR 2 times a day to allow 5 to 10% orts (as-fed basis). Milk production was recorded at the last week of each period and milk samples were collected at the last 2 d of each period. Data were analyzed as a 3 × 3 Latin square using the GLM procedure of SAS (2001). The model included effects of diet, period and cow. Least squares means are reported throughout and significance was declared at P < 0.05. Table 1 shows the results of milk production and components. Chemical treatments of whole barley grain increase milk production, but the concentration of fat, protein, lactose, solid not fat (SNF) and milk urea nitrogen (MUN) did not change in diets. The results of the current experiment reveals that chemical treatment of whole barley grain with sodium hydroxide had no significant effects on milk components, but milk production increased when treated whole barley grain included in diets.

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