The Wyoming toad (Bufo baxteri) and Houston toad (Anaxyrus houstonensis) are endangered species reared for restoration by the US Fish and Wildlife Service and partners. Classically defined nutritional requirements for toads are not established. In the wild, toads benefit from a diverse prey base fortified with naturally occurring nutrients. When in captivity, it becomes increasingly difficult to meet the nutritional needs of toads, and a variety of prey items are utilized to provide nutrition to toads. This has led to presumptive nutritional health-related issues, including malnutrition, developmental and reproductive problems, disease, and death. To meet nutritional needs, it is important to understand the organism’s nutritional requirements then administer these key nutrients effectively at the appropriate levels.
Three experiments were conducted at the Bozeman Fish Technology Center to quantify dietary fortification levels in Turkestan cockroaches. The first experiment was to determine a time course of vitamin fortification utilizing the current feeds for roaches and a complete vitamin supplement to boost tissue stores in feeder roaches. The second experiment quantified the efficacy of gut loading on vitamin composition of roaches. The third experiment tested the efficacy of dusting insects with vitamin supplement and the residual time of fortification.
The first experiment showed that dietary vitamin fortification was time dependent and diet dependent. Riboflavin and pyridoxine demonstrated linear increases in body concentrations over the 28-day trial for the high supplement diet. The fat-soluble vitamins cholecalciferol (D3) and retinol (vitamin A) plateaued by day 7 in roaches consuming the high supplement diet. The second experiment tested the ability of gut loading to increase vitamin fortification in roaches. The gut load was able to increase roach vitamin levels in by 67-97% for beta carotene and up to 2900% for vitamin D3 (Fig 2), dependent of gut load formulation. The efficacy of dusting will be presented.