Study On The Development Of T Lymphocyte And Tissue Structure Of Spleen In Broiler And Layer Chickens

In order to learn the change of tissue structure, tissue localization and distribution of T lymphocytes and subpopulation, and the law of growth on spleen of chicken, 10 broiler chickens on 1, 3, 5, 7, 14, 21, 28, 35, 42, 49 day-old and 10 layer chickens on 1, 5, 7, 12, 19, 26, 33, 40, 54, 68, 82, 96 day-old were selected randomly in each period,respectively. Spleen were weighted, and length and width of spleen were measured. Meanwhile paraffins section were made for HE staining, then the diameter of splenic node and area of periaterial lymphoid sheath were measured; At the same time, spleen were made cryosections for immunohistochemistry in each period, respectively. The result showed the ratio of white pulp to red pulp had been stable from 19 to 26 day-old; periaterial lymphoid sheath(PALS) could be observed in the spleen of 12 day-old chicken;splenic node could be observed in 14 day-old broiler chickens, and in 12 day-old hen layers and 19 day-old cock layers, respectively. The change of weight, length and width of spleen in broiler chickens tended to rise with ages; The ratio of spleen weight, the diameter of splenic node and the area of PALS were growing before 42 day-age, then reduced. The change of trend in hens and cocks were basically alike. weight, length and width of spleen were growing with ages; The ratio of spleen weight and the diameter of splenic node were growing before 68 day-age, then were reduced and stable; the area of PALS was growing before 40 day-age, then decreased after 40 day-age. CD3+ and CD8+ T cells were mainly distributed in PALS and red pulp; CD4+ T cells were mainly distributed in PALS. The number of CD3+, CD4+ and CD8+ T cells tended to rise befor 21 and 26 day-age, then were stable in broilers and layer chickens, respectively; CD4+ T cells were found in splenic node, but no CD8+ T cells. Conclusion, Spleen of broiler and layer chickens grew to peak at 42 and 68 day-age, respectively, then decreased. The number and distribution of CD3+, CD4+ and CD8+ T cells were stable in 21 and 26 day-old in broiler and layer chickens, respectively.