Binds galactose. Exerts immunomodulatory effects on host peripheral blood mononuclear cells to down-regulate host immune response (PubMed:25879191, PubMed:27337943, PubMed:28870237). Hemagglutinates human, dog, rabbit, chicken and mouse erythrocytes but does not hemagglutinate the erythrocytes of goat, its natural host (PubMed:17125929). (Microbial infection) Interacts (via domain galectin 2) with goat TMEM147 (PubMed:27337943, PubMed:28870237). Interacts (via domain galectin 1) with goat TMEM63A (PubMed:25879191, PubMed:28870237).