NULL EFFECT OF DIETARY AROCLOR 1254 ON HEPATOCELLULAR-CARCINOMA INCIDENCE IN RAINBOW-TROUT (SALMO GAIRDNERI) EXPOSED TO AFLATOXIN-B1 AS EMBRYOS

  • 1 January 1980
    • journal article
    • research article
    • Vol. 4  (5-6) , 9-16
Abstract
Four lots of 200 rainbow trout embryos were exposed to 200 ml solutions of aqueous 0.5 ppm aflatoxin B1 (AFB1) for 1 h and 4 lots of 200 rainbow trout embryos were sham-treated for 1 h. After hatching and swimup, 100 fry from each group were selected for a feeding trial. Two groups of AFB1-treated and 2 groups of sham-treated fry were fed a control diet, while corresponding groups of AFB1-treated and sham-treated fry were fed the control diet plus 100 ppm Aroclor 1254 for 1 yr. Samples were taken at 9 and 12 mo. to monitor tumor incidence, Aroclor 1254 accumulation and histopathology. At the end of 12 mo., the liver cancer incidences in the combined AFB1-treated, control diet groups and the AFB1-treated, Aroclor 1254 diet groups were essentially the same, 65.8 and 63.9%, respectively. One trout in the sham-control, Aroclor 1254 diet group had a single liver cancer but the sham-control, control diet group had none. The Aroclor 1254 fed groups had significantly higher liver to body weight ratios at 12 mo. but not at 9 mo. Levels of accumulated Aroclor 1254 were .apprx. 75 ppm on a whole fish basis at 12 mo. Glycogen depletion of hepatocytes and splenic hyperemia were the only tissue changes induced by Aroclor 1254.