As most antibiotics are water-soluble, many that are used in the
animal food-producing industry are poorly adsorbed in the gut of the
animal, resulting in as much as 30–90% of the parent compound being
excreted via feces or urine (Alcock et al., 1999). Usually, the usage dose
of antibiotics varies from 3.0 to 220.0 g/kg of feed, depending on the
types and sizes of animals and the type of antibiotic