[Testing of poultry for susceptibility to sarcoma viruses in the C subgroup]

Experiments were performed to test the conventional chickens of the Ross I and Tetra-B broiler hybrid and the Shaver Starcross 288 and Slovgal laying hybrid for their susceptibility to the poultry sarcoma virus of subgroup C (B77). The chickens were inoculated six days from hatching and the first sarcomata began to appear at the inoculation spot on the fourth day. The first deaths were observed on the eighth day from inoculation, and the necropsy revealed frequent metastases. Regressive fluid was also found to develop in some cases. On the basis of the haematological examination of all hybrids, significant lymphocytopenia and heterophilia were determined; in addition to this, a significant drop in the basophile count was ascertained in the Tetra-B hybrid and a significant rise in the monocyte count was found in the Slovgal hybrids. Also, a frequent occurrence of a high number of large lymphocytes, a random occurrence of large thrombocytes, and individual myelocytes and metamyelocytes were also observed. The results suggest that the tested poultry represent progressive (highly susceptible) types of poultry, in relation to sarcoma virus of subgroup C.