Effect of Thymectomy and Bursectomy on Precipitin and Natural Hemagglutinin Production in the Chicken

Open Access
Publisher Website
Google Scholar
Abstract
Summary: Thymectomy of chickens during the first 3 days of age does not consistently affect precipitin production to bovine serum albumin when challenged at 6 to 9 weeks of age. In some cases, thymectomized groups did not differ in mean peak titer from controls; in some cases the response was significantly lower; in one case the response was significantly higher. This variation was not evident for the time necessary to clear antigen from the circulation. Of intact and sham control birds 100% responded by producing precipitins, whereas 6% of the thymectomized birds did not give a detectable response. This frequency of negative responders was statistically significant. There was a tendency for groups with greater amounts of residual thymic tissue to give higher mean precipitin titers. However, the titers of birds with no residual thymus fell in a range very similar to that of the controls. The development of natural hemagglutinins was not affected by thymectomy. Splenectomy performed from 2 to 10 days of age significantly delayed the appearance of precipitins but did not affect the mean peak titer. Bursectomy at 1 to 2 days of age reduced the mean peak precipitin titers and the natural hemagglutinin titers drastically. Most birds did not give a detectable response.