Cumin seed improves nutrient intake and milk production by dairy cows

•Cumin seed was fed to lactating dairy cows at levels of 0, 100, 200 and 300 g/d.•Diets with up to 200 g/d of cumin seed improved nutrient intake and milk production.•Further increase in level of supplementation resulted in reduced efficiency.

A study was conducted to determine the effects of dietary supplementation with cumin seed (Cuminum cyminum) on nutrient intake, milk production and blood metabolites of lactating dairy cows. Eight Holstein dairy cows (average days in milk, 35 ± 5; body weight, 660 kg ± 15) were allocated to a replicated 4 × 4 Latin square design with four 21-d periods. Experimental diets contained increasing doses of cumin seed: 0 (control group), 100, 200 and 300 g/cow/d. Diets were prepared as a total mixed ration and delivered four times daily. Each period included 14 d of adaptation and 7 d of sampling for dry matter intake (DMI), milk production and composition, and blood metabolites. The DMI increased curvilinearly (P ≤ 0.05) from 22.8 to 25.2, 26.0 and 25.8 kg/d when 0, 100, 200 and 300 g/d cumin seed were fed, respectively. Also, milk yield increased curvilinearly with level of cumin seed (average 47.9, 52.5, 55.1, and 53.6 kg/d for the four levels, respectively; P ≤ 0.05). The yield of milk components was similar to milk yield (P ≤ 0.05) except for fat and 4% fat-corrected milk yields, which were not significantly affected by the treatments. The concentration of glucose, blood urea nitrogen, and beta-hydroxybutyric acid in the blood were unaffected by the treatments but the concentration of cholesterol tended to be decreased (P = 0.08) with increasing cumin seed in the diet. In general, our findings indicate that supplementing lactating dairy cow diets with up to 200 g/d of cumin seed could improve performance, but a further increase in level of supplementation might result in reduced efficiency.