1965 Volume 31 Issue 10 Pages 818-826
In 1962, some deformities (scoliosis or lordosis) of rainbow trout fed mainly with artificial dried diet were found in many fish ponds.
The cause of the deformity of rainbow trout has been studied from a nutritional viewpoint. From the results shown in Tables 1 to 5, it was revealed that the deformity was developed by the deficiency of, L-ascorbic acid in the diet used. The symptoms may essentially be included in the category of scurvy of higher animals. The deformity observed can tentatively be classified into 3 types a, b and c according to the appearance of the symptoms which varied with the size of fish (Figs.1 to 3).
Halver et al.1) have reported the development of scoliosis in rainbow trout fed the diet deficient in tryptophan. It is reported16), however, that the requirements of ascorbic acid of guinea pig considerably increase under the tryptophan deficient condition. Thus it is considered that the scoliosis reported by Halver et al. may have arised from an ascorbic acid deficiency.
The present studies also revealed that p-aminobenzoic acid was not essential dietary factor for rainbow trout as previously reported by Halver et al.2)