The same individuals used in the experiments reported in the previous paper were examined.
Weight gain and hep0ato-somatic index decreased depending on the Cd content of the feed in most experiments. Lateral curvature of the vertebral content by lateral bending of a/a few centrum/centra was observed in the fish (14% of 93 individuals in fish administered with Cd≥140 ppm) that had exhibited violent swimming and tetany during the experiment.
In Cd administered fish, abnormal black granules which accumulated around blood vessels were observed in the liver, and degeneration (thin wall) of proximal renal tubules and cells that seemed to have lost the protoplasm were observed in the kidney.
A possible mechanism for the lateral curvature of the vertebral column may be conjectured, based on the results described in the prevent and previous papers, as follows: disturbance of the balance between Ca and inorganic P in the plasma caused by degeneration of renal tubules attributable to orally administered Cd→low Ca and high inorganic P levels of the plasma as well as low Ca content of vertebrae→hyperexcitability of the nervous system and muscles→violent swimming and tetany→lateral bending of a/a few centrum/centra→lateral curvature of the vertebral column.