Long-term in vivo carcinogenicity test of fish meal pyrolysate in Syrian golden hamsters.

The carcinogenicity of fish meal pyrolysate was examined in noninbred Syrian golden hamsters of both sexes. Hamsters were given a diet containing 5%, 10%, 20% or 40% fish meal pyrolysate for 102 weeks in Experiment 1, and 10% or 20% fish meal pyrolysate for 112 weeks in Experiment 2. Hamsters in control groups in both experiments were fed a normal basal diet. Various tumors were found in both experimental and corresponding control groups, but there was no significant difference in the incidence of any tumors between the experimental and control groups. Thus, the fish meal pyrolysate tested was not carcinogenic to Syrian golden hamsters under these conditions. In male hamsters the severity and incidence of fatty degeneration of the liver and chronic nephropathy tended to correlate with the concentration of fish meal pyrolysate in the diet. With females, however, the correlation was not so clear. In neither sex did the presence of atrial thrombosis or systemic amyloidosis appear to be dependent on the dietary concentration of fish meal pyrolysate.