Vol. 11, Special Issue 10 (2022)

Purpose: The study of histo-topography of B and T lymphocytes in certain lymphoid organ of Pati duck (Anas platyrhynchos domesticus) is great value in regards to the immunity of duck. The aim of this study was to know the immune status of duck.

Materials and Methods: In present study, 40 numbers of Pati duck of Assam were utilized. The samples were collected from lymph node, Gut Associated Lymphoid Tissue of different parts of the intestine and bursa of Fabricius of Pati duck. These samples were fixed in 10% neutral buffered formalin solution and were processed as per the standard technique of procedure (Luna, 1968). The paraffin blocks were sectioned in Shandon Finesse microtome at 5µm thickness and the sections were stained with Mayer’s Haematoxylin and Eosin staining technique for histo-topography of B and T lymphocytes as per the standard methods of Luna (1968). By the Mayer’s Haematoxylin and Eosin staining technique, the B and T–lymphocytes can identify in high magnification. The B-lymphocytes were nucleated and T-lymphocytes were non-nucleated.

Results: In the current investigation, the lymph node and gut associated lymphoid tissue of intestine as well as bursa of Fabricius of Pati duck were studied. In present study, showed that there were two lymph nodes: cervical and lumbar lymph nodes. Gut associated lymphoid tissue normally included Peyer’s patches and solitary lymphatic nodules. Both the cervical as well as lumbar lymph node of Pati duck composed of inner cortex and outer medulla. Different sizes of numerous follicles were observed in cortex of lymph node of Pati duck. B-lymphocytes were observed in the centre of cortex whereas T-lymphocytes were observed in the periphery of the germinal centre of these follicles. The B-lymphocytes were nucleated and T-lymphocytes were non-nucleated. The inner surface of the bursa of Fabricius was composed of several mucosal folds which were projected into the lumen. Numerous polyhedral shaped bursal follicles were observed in the lamina propria of each fold. Each bursal follicle was consisting of outer cortex and inner medulla. The cortex of bursal follicle was occupied by closely packed small B-lymphocytes. The paler medulla contained fewer B-lymphocytes of various sizes. Peyers patches as well as solitary lymphoid nodules were distributed in the important strategic areas of intestine of Pati ducks. The lamina propria of duodenum was made up of loose connective tissue and diffuse lymphatic tissue. These diffuse lymphatic tissue contained B-lymphocytes and T-lymphocytes. The tunica muscularis layer of jejunum contained lymphoid follicles which were remained in cluster. These lymphoid follicles were separated from each other by a narrow inter follicular area. The centre of these follicle contained B-lymphocytes along with plasma cell whereas the periphery of these follicle contained T-lymphocytes. The B-lymphocytes were nucleated and T-lymphocytes were non-nucleated. The tunica muscularis layer of Ileum contained cluster of lymphoid follicles. These lymphoid follicles were separated from each other by narrow inter follicular area. B-lymphocytes were observed in the centre of lymphoid follicle whereas T-lymphocytes were observed in periphery of lymphoid follicle. Lymphoid follicles were found in the ileo-caecal junction. The centre of these lymphoid follicle contained B-lymphocytes whereas the periphery of the lymphoid follicle contained T-lymphocytes. There was less infiltration of lymphatic tissue in lamina propria of colo-rectum compared to the other part of intestine. The solitary lymphatic nodules were found in the lamina propria and tunica muscularis of rectum but there was no aggregation of nodules.

Conclusion: This study will helpful to the duck farmer, poultry scientist, physiologist and microbiologist for vaccine production and duck meat, egg production and diseases control regime.