海産魚のチアミナーゼIの研究-VII

サンマによるハマチの餌料性疾患とB₁の投与効果

抄録

The existence of thiaminase I in anchovy, Engraulis japonica, and saury, Coiolabis saira, was elucidated in a previous paper. And it is well known that yellowtail which are fed only anchovy for a long period develop a feedinduced disease.
The present study investigated whether the yellowtail fed with saury showed the same disease as the yellowtail fed with anchovy or not. Yellowtail with an average weight of 13.3g were fed saury with or without added thiamine nitrate for 47 days. The thiamine nitrate used was coated with fat in order to prevent its decomposition by thiaminase.
The yellowtail fed saury showed a feedinduced disease, with symptoms such as anorexia, dark colored body, retarded growth, loss of equilibrium, and high mortality. In these fish, the contents of thiamine in ordinary muscle, the triglyceride and cholesterol in serum, the hematocrit value and hemoglobin in the blood all significantly decreased, while the pyruvic acid in the blood increased remarkably. These symptoms of the yellowtail were in agreement with those of the yellowtail fed with anchovy. On the other hand, the yellowtail fed during the entire period with the saury to which was added the thiamine nitrate showed good growth and no mortality.