PhytoMilk: Effects of botanical composition and harvest system of legume/grass silage on fatty acid, α-tocopherol and β-carotene concentration in organic forage and milk

摘要

Red clover and high proportion of forage in dairy cow diet increases the concentration of bioactive substances in milk, e.g. unsaturated fatty acids and antioxidants. In the present experiment twenty-four Swedish Red dairy cows were fed three silages in a Latin Square design to study the effect of silage botanical composition and harvest time on milk fatty acid, α-tocopherol and β-carotene concentration. The silages were red clover/grass silage (mixture of first and second cut), red clover/grass silage (mixture of first, second and third cut) and birdsfoot trefoil/grass silage (mixture of first and second cut). Botanical composition and harvest system affected silage vitamin and fatty acid concentration with higher concentrations of α-linolenic acid, α-tocopherol and β-carotene in red clover/grass silage (mixture of three harvests). Milk linoleic and α-linolenic acid concentration was higher with the two red clover diets but α-tocopherol, β-carotene and retinol concentration was not affected.