The requirement of Cichlasoma urophthalmus (Günther) fry for pantothenic acid and the pathological signs of deficiency

Abstract. Fry of Cichlasoma urophthalmus (Günther) weighing 160-175 mg were fed for 75 days on diets containing seven different levels of calcium pantothenate. Fish fed on the three lowest inclusion levels (up to 0,10 and 20 mg/kg) exhibited a variety of external signs and high mortalities. Fish fed on the higher inclusion levels (40, 60, 80, 120 and 320 mg/kg) did not show external pathologies. At the end of the experiment there was no significant difference in these diets (P<0.01) in final weight, individual weight gain, individual food intake, food conversion ratio, and specific growth rate. Marked interlamellar lesions were observed in gills of fish fed on the lowest inclusion level diets. The lesions ranged from oedema, hyperplasia covering all the secondary lamellae to the complete fusion of adjacent filaments. These fish also developed necrosis of the pancreas, whilst fish fed diets up to 80 mg/kg showed marked glycogen deposition in the hepatic cells. For the first time it is reported that fish deficient in pantothenic acid showed ceroid deposition in the hepatic cells and spleen. Fish fed on diets containing 80-320 mg/kg did not show external or histological changes. It is thus recommended that the diet of C. urophthalmus fry must be supplemented with at least 80 mg/kg diet to give maximum growth and to avoid gross and histologicai signs of deficiency.