Coslik AH, Ward AM, McClements RD. 2009. Gut loading as a method to effectively supplement crickets with calcium and vitamin A. In Ward A, Treiber K, Schmidt D, Coslik A, Maslanka M, Eds. Proceedings of the Eighth Conference on Zoo and Wildlife Nutrition, AZA Nutrition Advisory Group, Tulsa, OK.
Limited quantities of vital nutrients such as calcium and vitamin A in crickets have led to the occurrence of diseases such as rickets, osteomalacia, metabolic bone disease (calcium deficiency) and more recently, squamous metaplasia or “short tongue syndrome” in amphibians. Gut loading has been an effective method to supplement feeder crickets with both calcium and vitamin A. A dose of 0.4 ug vitamin A/g bodyweight/week given orally maintained captive Puerto Rican crested toads (Bufo lemur) without signs of vitamin A deficiency and squamous metaplasia at the Fort Worth Zoo. To achieve a similar supplementation level and a 1:1 calcium to phosphorus ratio, a gut loading diet 9.07% calcium and 429 ug/g retinol on a dry matter basis was fed for seven days. Crickets were removed at days two, four, and seven for subsequent dry matter, calcium, phosphorus, magnesium, potassium, sodium, iron, zinc, copper, manganese, molybdenum, vitamin A, vitamin E, beta carotene, lutein, canthaxanthin, echinenone, beta-cryptoxanthin, and zeaxanthin analysis. At day zero, neither calcium (0.15%) nor vitamin A (0.20 ug/g cricket) met minimum carnivore requirements. The desired 1:1 calcium:phosphorus ratio, calcium (0.6%) and vitamin A (12 ug/g cricket) levels were achieved by day two (1.60% and 17.0 ug/g cricket, respectively) on the gut-loading diet. This study supports the hypothesis that gut loading is an effective method of vitamin A supplementation.33_CoslikCricketVitA.pdf     204 KB