Studies on bronchus associated lymphoid tissue (BALT) of black Bengal goat

Abstract

Bronchus Associated Lymphoid Tissue (BALT) were collected from clinically healthy zero day and month wise from one month to fifth months old Black Bengal goats (Capra hircus). Bronchus associated lymphoid tissue (BALT) was not found macroscopically; however from date of birth to till the last experimental age group, it was identified microscopically in caparine lung. At birth the small lymphocytic aggregation was found near the respiratory pathway. The aggregation of lymphocyte was found in diffused form rather than in the nodular form. Mostly they were found in 1st and 2nd order of bronchus and at the respiratory bronchioles. From 1st month onward typical lymphonodular tissue was observed in the same area as described at the date of birth. The sizes of lymphnodules were increased according to advancement of age. BALT showed CD4+ T lymphocyte, MHC- II + expressing cells, IgM positive cells and CD8+ T lymphocytes in all the experimental groups. CD4 positive cells population was found to be more as compare to the CD8 cells. B lymphocytes were identified scatteredly in the bronchus associated lymph nodes and also within the interalveolar spaces. MHC II Positive cells were found in the interalveolar spaces, within alveoli and also at BALT.