Pathomorphological cnanges in lymphoid organs of calves with cryptosporidiosis

Studies of the structure of lymphoid tissue in the organs of calves showed that cryptosporidia penetrating the intestine can cause infectious process under the rise of immune deficiency. The study also identified the dramatic cell depletion in periarterial T-dependent zones resulting from the invasion by cryptosporidium in the white pulp of spleen of sick calves affected by local vascular disorders in the central arteries and capillary network. The erythrography processes caused by macrophages and the accumulation of hemosiderin were noticeably increased in the red pulpof the spleen. An increased delimphotization of cortical and medullary substances was observed in the thymus of sick calves. Intensive cell inversion following an increase in the migration of small lymphocytes into the medulla completely erased the rest of cortex-medullary line. The severity of secondary immunodeficiency was also indicated by damage to histomatogenous barriers, especially the capillary network of the cortex substances of the lobules...