Eight multiparous (n = 2) early lactating Holstein cows were used in a 4 × 4 Latin square design to determine effects of different levels of guar meal on the performance of dairy cows. Treatments were including 4 levels of guar meal: T1) 0, T2) 4, T3) 8, T4) 12% of DM that substitute to soybean meal. Treatments effect on DMI (kg/d) were not significant (P > 0.05). Milk yield were increased for cows fed T2 compared with other treatments (43.392, 46.480, 44.100 and 43.080, respectively) (P < 0.05). Milk fat (%) was increased for T2 compared with T3 and T4 (P < 0.05), but had no difference between T1 and T2 (P > 0.05). Milk protein was not influenced by treatments (P > 0.05). Treatments effect on pH were significant (P < 0.05), cows fed T2 had lower pH than control (6.58 vs. 6.36). It was concluded that substitution 4% of soybean meal with guar meal had the best effect on performance.

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