Use of macro- and microalgae in animal nutrition

Abstract

The recent restrictions imposed by the European Union on the use of antibiotics as growth promoters in animal feed have led to a significant increase in the demand for alternative protein sources. Algae, recognized for their abundance and nutritional value, have emerged as a promising substitute for soybeans in animal nutrition. Although the current cost of algae limits its widespread use as a protein supplement, numerous research studies have highlighted the beneficial effects of even small amounts of algae added to animal feed on growth performance and immune function. Additional research and development initiatives are required to establish algae as a standard raw material in animal feed production. Moreover, there is an increasing demand for additives that improve the quality of animal products, such as natural pigments, carotenoids, and polyunsaturated fatty acids, all of which are plentiful in algae. Algae boast vitamins, antioxidants, and growth-promoting substances that can stimulate the immune system, improve feed intake and utilization, and support reproductive processes, thereby potentially increasing the value of animal products intended for human consumption. With the global population on the rise, the demand for animal products is escalating, highlighting the necessity for cost-effective animal feed alternatives that maintain quality standards. Algae have attracted interest as potential feed additives due to their unique composition, which includes proteins, carbohydrates, vitamins, and bioactive compounds. Their autotrophic characteristics position them as a promising solution for sustainable biomass production, particularly within the animal feed sector. This review aims to explore macro- and microalgae concepts, cultivation methods, general applications, and their compatibility with the nutritional requirements of various farm animals and poultry.