Comparative susceptibility of chickens, turkeys and ducks to infectious bursal disease virus using immunohistochemistry

Abstract

Twenty chicks, 12 turkey poults and 10 ducklings, all 5 weeks old were infected with 2 x 10(3.5) chick LD(50) IBD virus to determine the course of the virus in the 3 poultry species. Uninfected control birds were kept separately. Two infected and 2 control birds/species were euthanized at time intervals between 3 and 168 hours post infection (pi). Sections of thymus, bursa of Fabricius, spleen, liver, kidney, proventriculus and ceacal tonsil were stained for the detection of IBD virus antigen using immunoperoxidase technique. IBD virus antigen positive cells stained reddish-brown and the amount of such cells in tissue sections were noted and scored. Stained cells were present in all organs examined for up to 168 hours pi in the 3 poultry species except ceacal tonsils of ducks at 72 and 120 hours pi. Antigen score was highest in chickens and least in ducks as reflected by average of total scores/sampling time of 12, 10.8 and 8 in chickens, turkeys and ducks respectively. Total antigen score/sampling time in infected chickens peaked twice; 24/48 and 144 hours pi, whereas such bi-phasic peaks were absent in turkeys and ducks. Range of total antigen score at different sampling times was 7-17.5 in chickens, 10-13 in turkeys and 7-10 in ducks indicative of marked viral replication in chickens. Presence of IBD viral antigen in organs of all 3 poultry species is indicative of infections. The innate ability of turkeys and ducks to prevent appreciable replication of IBD virus after infection requires further investigation.

Histopathological and immunohistochemical diagnosis of infectious bursal disease in poultry birds

“…In various previous experimental studies, IBDV antigens have been detected in macrophages within follicles, the interstitium, and the lymphoid cells of bursa of Fabricius, e.g., by Oladele et al . [ 21 ], but in the present study, the viral antigens were found mainly associated with bursal lymphoid cells and in bursal epithelium in some cases ( Figure-4 ). The findings can be related to the findings of Tippenhauer et al .…”

“…The presence of viral antigen was also appreciated in the bursal interfollicular connective tissue ( Figure-5 ) as well as the bursal epithelium which was also reported by Oladele et al . [ 21 ]. The distribution of viral antigen varied from being localized ( Figure-6 ) to focal to diffuse.…”

“…To statistically ascertain the relationship between the histopathological changes in the bursas from affected birds and the immunohistopathological scores, the immunohistopathological scoring was done using the scoring scale of 0-3, as applied by Oladele et al . [ 21 ], as shown in Table-3 . For a statistical comparison to be drawn, the mean and the standard deviation of the respective histopathological changes were also calculated, as shown in Table-4 .…”

“…This immunohistopathological scoring was done using the scoring scale of 0-3, as applied by Oladele et al . [ 21 ] where, three sites in each tissue section were observed under the microscope and scored.…”

Growth and Replication of Infectious Bursal Disease Virus in the DF-1 Cell Line and Chicken Embryo Fibroblasts

“…Two serotypes of IBDV (1 and 2) were distinguished by cross-virus neutralization [4]. The IBDV strains of serotype 1 are pathogenic to chickens [5] and further classified as classical virulent IBDV (cvIBDV), very virulent IBDV (vvIBDV), antigenic variant IBDV (avIBDV), and attenuated IBDV (atIBDV) [6]. Strains of serotype 2 are naturally avirulent for chickens [7, 8].…”