Seaweeds are a diverse group of plants with a complicated and contentious
taxonomy. In general, seaweeds are classified into three groups, brown
(Phaeophyceae), red (Rhodophyceae), and green (Chlorophyceae), based on pigment
variability. Seaweeds have tremendous potential for human consumption, cosmetics,
fertilizers, industrial gums, and chemicals. Researchers have also discovered that
seaweeds have been used as animal feed in the livestock sector for thousands of years.
However, out of the approximately 10,000 types of seaweeds, only a few are used in
animal consumption, such as Ascophyllum nodosum, Laminaria species, Lithothamnion
species, Macrocystis pyrifera, Sargassum species, Palmaria palmata, and Ulva species.
According to previous studies, seaweeds have been incorporated into the diet of cows
at less than 2% of the dry ingredients, but the isolation of compounds responsible for
reducing methane production by cattle has not been done yet. It is crucial to isolate the
various bioactive compounds in seaweeds and incorporate them into traditional animal
feed to improve their nutritional and functional characteristics. Seaweeds have also
been utilized in fish feed, where finely ground seaweed meal made from brown
seaweeds acts as a binder in formulated feeds, with the alginate present in seaweed
functioning as the binder. Although successful results have been achieved with
seaweed consumption for animal feed, researchers have raised concerns about metal
uptake from the surrounding water.
Keywords: Animal feed, Bioactive compounds, Livestock sector, Microalgae.
