EFFECTS OF 3 DIFFERENT DIETS ON SURVIVAL AND GROWTH OF LARVAE OF THE AFRICAN CLAWED FROG XENOPUS-LAEVIS

The African clawed frog Xenopus laevis has economic value in research, education, and the pet trade and has considerable potential for human consumption. In spite of its importance, little experimental research has been conducted on rearing techniques. particularly on diets. This study reports the survival and growth (in weight) of larvae reared on three diets: Purina Trout Chow, Purina Catfish Cage Chow, and a mostl y grain-derived diet, referred to as experimental diet A. Twelve aquar ia (37.9 L) were used with four replicates per diet. Forty newly hatch ed larvae were placed in each aquarium and fed ad libitum. The experim ent was terminated when several larvae developed front legs, which ind icated the onset of metamorphosis and feeding cessation. Larvae were s acrificed by treatment with tricaine methanesulfonate (MS-222), freeze -dried, and individually weighed to the nearest 0.1 mg. Survival was n ot significantly different (chi-square test) among the aquaria, but we ights of larvae were significantly different (Kruskal-Wallis and Mann- Whitney U-tests); the trout chow produced the heaviest larvae, and exp erimental diet A produced the lightest larvae. The high crude protein content (60.7%) and large amount of animal-derived ingredients of the trout chow may have been responsible for the higher weights attained t han with the two other diets.