This paper focuses on the role of n-3 fatty acids as a nutrient crucial to the proper functioning of reproductive and immune systems in cattle. Emphasis was placed on the connection between maternal and offspring immunity. The summarized results confirm the importance and beneficial effect of n-3 family fatty acids on ruminant organisms. Meanwhile, dietary n-3 fatty acids supplementation, especially during the critical first week for dairy cows experiencing their peripartum period, in general, is expected to enhance reproductive performance, and the impact of its supplementation appears to be dependent on body condition scores of cows during the drying period, the severity of the negative energy balance, and the amount of fat in the basic feed ration. An unbalanced, insufficient, or excessive fatty acid supplementation of cows’ diets in the early stages of pregnancy (during fetus development) may affect both the metabolic and nutritional programming of the offspring. The presence of the polyunsaturated fatty acids of the n-3 family in the calves’ ration affects not only the performance of calves but also the immune response, antioxidant status, and overall metabolism of the future adult cow.

The present study aimed to evaluate the effect of supplementation of cow’s diet with four different herbal blends on the mineral profile in the plasma and milk of cows in the first stage of lactation. The experiment involved 50 cows divided into five groups. Four herbal blends were used as an experimental factor. A full ration of 100 g of the herbal supplements per 100 kg b.w. per day was included in the cow’s diet from one week before the planned calving to the end of the third month of lactation. The feed intake by the dairy cows was assessed in three 3-day cycles in lactation weeks 6, 7, and 8. Concurrently, blood and milk were collected from these cows. The content of selected minerals was determined in the feed rations, herbal blends, milk, and plasma. The study showed that herbs, besides being a source of bioactive compounds, should be considered a beneficial source of minerals, especially microelements like copper, zinc and iron, and might affect the mineral homeostasis in the organism. The introduction of different herbal blends affected not only the mineral profile of blood but most notably the milk mineral profile.