A gelatin-based feed for individually tailored drug delivery to adult zebrafish

Current approaches to drug delivery in adult zebrafish have significant limitations such as need for confinement, anesthesia, and/or dosing that is not based on body weight. To circumvent these challenges, we developed a non-invasive gelatin-based feed that is easily pipette into individually tailored morsels according to weight. Our feed was readily eaten by zebrafish (< 1 minute) with minimal leaching of compound (< 5%) when placed in water. We used our feed to deliver an NMDAR antagonist (MK-801, 4 mg/kg) prior to exposure to a novel tank. Consistent with prior work, we found that MK-801 caused a decrease in predator-avoidance/anxiety-like behaviors. We also found that MK-801 increased locomotion in male fish, but not females. Our simple, easy to prepare, and individually tailored gelatin-based feed now brings pharmacological manipulations of adult zebrafish in line with best practices used in other vertebrate model organisms.