Gut-Loading Diet Evaluation for Crickets (Acheta domesticus), Mealwarms (Tenebrio molitor), and Superwarms (Zophobas moria) for the Purposes of Optimizing Institutional Protocols

Abstract. Several papers over recent years have looked at the practice of gut loading feeder insects for the purposes of improving nutrient composition of these diet items for an array of insectivores; most important being amphibians, reptiles, and birds (Attard, 2011; Coslik et al., 2009; Hunt et al., 2001). These particular species are especially prone to nutritional maladies including metabolic bone disease, rickets, osteomalacia, and hypovitaminosis A (McWilliams & Leeson, 2001; Pessier & Rodriguez, 2015). The Oregon Zoo recently experienced multiple cases in our herpetology and bird departments that necessitated an evaluation of gut loading protocols throughout the zoo. These include presentation of hypovitaminosis A in a rough-skinned newt, a ruddy duck, and hammerkop chicks, and possible metabolic bone disease in a Meller’s chameleon and red-billed hornbill chick.