Used to treat a wide range of bacterial infections in humans and animals, including respiratory, urinary tract, and skin infections. Commonly applied in veterinary medicine for treating infections in livestock and aquaculture. Also used in agriculture to control bacterial diseases in crops and to prevent infections in farmed fish. Frequently employed in research laboratories as a selective agent in cell culture and molecular biology to maintain genetically modified organisms carrying resistance genes. Its broad-spectrum activity makes it effective against both gram-positive and gram-negative bacteria.