Foci of altered hepatocytes induced in embryonal turkey liver

Fertilized turkey eggs were injected with N-nitrosomopholine (1-10 mg/egg) or urethane (0.1-10 mg/egg) prior to or during the first hours of incubation. Four days prior to hatching, the experiments were terminated and the livers of the embryos removed. The hepatocarcinogens induced focally arranged hepatocytes with morphological and metabolic changes that were similar to preneoplastic foci observed in rodent studies in vivo. Foci with enlarged cells and excessive storage of glycogen as well as basophilic foci with small cells, low in glycogen content and with frequent mitotic figures were found. The in ovo transformation of embryonal hepatocytes may be a promising rapid model of hepatocarcinogenesis.