[Immunologic response in bursectomized and non-bursectomized chickens inoculated with Newcastle disease virus (NDV) after administration of sheep erythrocytes (SRBC) or bovine serum albumin (BSA)].

Astra S hybrid chickens, bursectomized within 48 hours of life, were administered the following antigens: virus of Newcastle disease (NDV) in the fourth week of life and sheep red blood cells (SRBC) or bovine serum albumin (BSA) 10-12 days later. Level of antibodies to the antigens was determined in the sixth week of the birds' life. Administration of SRBC to non-bursectomized chickens inoculated with NDV brought about, in comparison with the chickens not administered SRBC, several-time increase in the titre of anti-NDV antibodies, the anti-SRBC antibodies in chickens inoculated and not inoculated with NDV stayed at the same level. Now, administration of BSA to non-bursectomized chickens inoculated with NDV, in comparison with those not stimulated with BSA, brought about a slight decrease in the titre of anti-NDV antibodies. Bursectomized chickens appeared to exhibit much weaker reaction to the three antigens than the non-bursectomized ones. Administration of SRBC to bursectomized chickens inoculated with NDV exerted no influence on the level of anti-NDV antibodies but, in comparison with those not inoculated with NDV, the titre of anti-SRBC antibodies in them increased twice. Inoculation of bursectomized chickens with NDV followed by administration of BSA brought about, in comparison with those not administered BSA, an increase in the titre of anti-NDV antibodies. At the same time bursectomized chickens inoculated with NDV exhibited a lower level of anti-BSA agglutinins in comparison with the not inoculated ones.