NETJROLYMPHOMATOSIS 3 



Erythroleukosis has been experimentally transmitted from affected to healthy 

 birds by inoculation of whole erythroleukotic blood by Furth (1931), and by 

 the author. 



In experiments in this laboratory, each chicken received intravenously 0.001 

 cc. of whole erythroleukotic blood per gram of body weight, with results shown 

 in Table 1. 



Also erythroleukotic plasma freed of blood cells and platelets by centri- 

 fugalization at 25,000 R.P.M. and made bacteriologically sterile by filtration 

 through 2 percent collodion membrane, transmitted the disease to susceptible 

 chickens. The plasma was inoculated intravenously into 60 chickens, until 

 each received 0.001 cc. of the ultrafiltrate per gram of body weight. This 

 experiment is reported in Table 1. 



Table 1. — Results of Inoculating Chickens with Erythroleukotic 



Blood and Plasma 



Erythroleukotic 

 Number of Age Unaffected ■ 



Chickens (Weeks) Total Died Recovered 



Inoculated with Whole Erythroleukotic Blood * 



20 2 5 15 13 2 



20 8 9 11 9 2 



20 24 12 8 5 3 • 



60 26 34 ' 27 7 



Inoculated with Erythroleukotic Plasma 



20 2 8 12 8 4 



20 8 13 7 4 3 



20 24 15 5 1 4 



60 36 24 13 11 



The data in Table 1 show that the causative agent in erythroleukosis was 

 filterable and passed through 2 percent collodion membranes in sufficient 

 quantity to reproduce the disease in susceptible chickens. Furthermore, the 

 results indicate that healthy chickens offered some resistance to the disease 

 and this resistance apparently increased with age. 



Since the chickens on these two experiments showed no symptoms or lesions 

 of neurolymphomatosis and, according to the Diagnostic Service reports, 

 erythroleukosis is not common in Massachusetts, the investigation was closed. 



MYELOLEUKOSIS 



Myeloleukosis is that form of leukosis in which immature leukocytes, known 

 as myelocytes, appear in the blood stream. Like the erythrocyte, the leukocyte 

 is formed in the bone marrow. Therefore, myeloleukosis presents the same 

 symptoms as erythroleukosis, and a common method of differentiation is by 

 examining stained blood smears and noting the predominating type of cell 

 present. 



