Effect of Dietary Seaweed Supplementation in Cows on Milk Macrominerals, Trace Elements and Heavy Metal Concentrations

This study investigated the effect of seaweed supplementation in dairy cow diets on milk yield, basic composition, and mineral concentrations. Thirty-seven Icelandic cows were split into three diet treatments: control (CON, no seaweed), low (LSW, 0.75% concentrate dry matter (DM), 13–40 g/cow/day), high (HSW, 1.5% DM, 26–158 g/cow/day). Cows fed same basal grass silage for a week, then introduced to assigned experimental 6 weeks. The mix 91% Ascophyllum nodosum: 9% Laminaria digitata (DM basis), feed, samples collected weekly. Data analyzed using linear mixed effects model, with diet, their interaction as fixed factors, ID random factor, pre-treatment week data covariate. When compared CON milk, LSW HSW had, respectively, less Se (−1.4 −3.1 μg/kg milk) more I (+744 +1649 milk), while also had Cu (−11.6 As (+0.17 than milk. minimal changes or concentrations Se, Cu, cannot be associated any consumer nutrition, but care should taken when I-rich is avoid excessive animal supply