Yuttapong Jitphatthanakul, Kidchakan Supamattaya, Dusit Nakachart, and Saithong Kaewchai

pp. 399 - 411

Abstract

The qualitative effects of fat-soluble vitamins (vitamin A, D, E and K) were studied in green
catfish. The experiment consisted of five treatments with three replicates each. The feed of formula 1 was
supplemented with complete vitamins while the feeds of formulae 2, 3, 4 and 5 were prepared using the
same feed components and vitamins as in formula 1, except that they were deficient in vitamins A, D, E and K, respectively. The experiment was carried out for a period of ten weeks in 200-l glass tanks. There
was no significant difference in growth performance or feed efficiency among the groups (P>0.05). The fish
fed diet without vitamin A supplementation had the lowest survival rate. External abnormalities of fish
were recorded such as hemorrhage at the fins, deformities of the barbels and fins, opened operculum, gill
of paler coloration and swollen abdomen. Additionally, the fish showed behavioral changes including
higher response to stimulus and sluggish swimming and remained at the corners of the tank and with
lower feed susceptibility. Result of blood analysis showed lower plasma protein, hematocrit and
hemoglobin than the fish fed other feeds. Histological examination showed pathological changes of the
gill, liver and kidney tissue. Fish fed the feed without vitamin D supplementation developed similar abnormalities, though of less severity, is those recognized in fish fed the feed without vitamin A supplementation. The hepatosomatic index of fish without vitamin D supplementation was highest among all
the treatments. No abnormality was noted in the fish given the feed containing all fat-soluble vitamins or
in those without vitamins E and K supplementation throughout the experimental period.