Red seaweeds (Sarcodiotheca gaudichaudii and Chondrus crispus) (i.e., Rhodophyta) contain a variety of different bioactive compounds, including sulfated polysaccharides, polyphenols, carotenoids, amino acids, proteins/peptides and lipids.
Studies demonstrate how red seaweeds may be a beneficial supplement to add to your chickens' diet. Red seaweeds have been shown to modulate the immune response and microbiota.
Seaweed supplementation increased the abundance of beneficial bacteria [e.g., Bifidobacterium longum (4- to 14-fold), Streptococcus salivarius (4- to 15-fold)] and reduced the prevalence of Clostridium perfringens in chickens. Supplementing their diet with 4% red seaweed helped to provide protection against Salmonella Enteritidis colonization (which can cause Salmonellosis) in one research study.