Hironari Fukuda

STUDIES ON THE ABNORMAL METABOLISM OF LIPIDS IN CULTURED SNAPPING-TURTLES, “AMYDA JAPONICA”.-III

Microscopic observation of the abnormal tissues of internal organs in three female snapping turtles, which typically showed serious illness in appearance, was made in this paper. The abnormalities observed in each internal organ are as follows (cf. Table 1 and Plate 1): Coelom fat is surrounded by thick membrane of connective tissue, containing a little of neutral fat and large quantity of denaturated lipid. In respect of the muscular system, morbid degenerations such as dispersal and atrophy were seen. As to the liver, such morbid degenerations as stagnation of sinusoid, dim swelling, disturbance of cell-cord, increase of reticulum fiber, cariopycnosis, decrease of glycogen, and numerous lipid granules were noticed. As for the kidney, morbidities such as stagnation of glomerulus, hyalin degeneration of Bowmans capsule, renal cast, dilatation of nephritic duct, and breakdown of nephritic duct cell were recognised as serious nephrosis. But in the spleen was seen general anemia only. From the above observations, the pathological features such as abnormal accumulation of denaturated lipid in coelom fat, dysfunction of liver and kidney, and hypoalimentary state were recognized distinctly.

Enzymatic Method for the Estimation of Freshnes of Fish. -II

Fig. 1 shows representative examples of the change of succinic dehydrogenase activity of fish tissues with incubation at 25°C. Although great variations in the enzymatic activity were observed among various tissues, a decrease in the enzyme activity of a certain sample tissue showed a significant correlation with decrease of its freshness. Therefore, the freshness of sample fish under test can be judged from decrease in the enzyme activity (freshness-index value E) of various sample tissues, and the values were compared with those values of fresh fish of the same kind. The freshness-index values of several fresh fish and deteriorated fish are given in Table 1.

Poisoning of Aquatic Animals with Some Toxic Substances-I

In an attempt to toxicity of some substances to aquatic animals, linearly arranged five pots supplied with running water were used (Fig. 1). Any change of behaviour of the experimental animals in them when exposed to waterborne toxic substances was noted against uormal conduct of the controls. Evaluation of toxicity was done by adding different weights on different signs of vector as revealed by locomotion of the animals in question and also on time required for the conduct. Toxicity was read in terms of minutes in reference to poisoning (Fig. 3). Threshold toxic concentration was graphically determined (Fig. 3). The limens for the teleost, Oryzias latipes, were found 1/16000000 CuS04, 1/15000000 KCN, and 1/1050000 NaOH.