More important mycotoxicoses of poultry Clinico-pathological. Review article

Clinical symptoms and pathomorphological changes of more important mycotoxicoses of different poultry species have been reviewed. In case of aflatoxicosis, inappetency, faintness, weakness and frequently ataxia, opisthotonus and spastic retroextension of extremities can be observed. The pathological investigation may reveal swelling, yellow colouration of liver with heamorrhages on its surface (Fig. 2), swelling of kidneys, dropsy in the pericardium and acute intestinal catarrh. The histopathological investigation may reveal disorganization of hepatic structure (dystrophy), and severe necrosis of parenchymal cells (fatty infiltration, necrosis, Fig. 3) which can be accompanied by proliferation of bile vessels (Fig. 4), nodular hyperplasia of hepatic cells and fibrosis. All avian species, except for domestic fowl (Gallus domesticus) are sensitive for F-2 fusariotoxicosis. Zearalenone has no effect on egg production, however the sperm cell production of males (drake, gander, turkey cock, guinea cock) - similar to the mammalians - is damaged. It causes fatty degeneration of germinal epithelium in the seminiferous tubules and later on atrophy and ceasing of spermiogenesis (Figures 5 and 6). The electron microscopic examinations revealed - besides the presence of fat droplets - necrosis (appearance of so-called myelin figurations), calcification of mitochondria (Fig. 7) in the cytoplasm and chromatin degeneration in the head of matured sperm cells (Fig, 8). Fusariotoxicoses caused by T-2 and other trichothecene skeleton toxins (HT-2 DAS, NIV, FX, DON). It causes diminution of body-mass gain, disturbed feathering and the flock will be ''scattered'' (Fig. 9). In case of higher toxin contamination, necrosis covered with crusted deposition develops on the bill, skin of the angle of mouth, on the tongue and palate (Figs 10, 11, and 12). Occasionally, motor disturbance and nervous symptoms can also be observed. During the gross-pathological examination,especially in case of mixed toxin contamination, a frequent observation is an acute, haemorrhagic hepatic dystrophy and tubulonephrosis as well as atrophy of lymphoid organs (bursa of Fabricii, thymus, etc., Figs 13 to 17). Damage of immune system predisposes for the manifestation of other diseases (e. g. caecal coccidiosis) and worsen the effect of vaccinations. In adult laying flocks, the egg production decreases (Figs 18 and 19), hatching ability worsens (Fig. 25), follicular degeneration and necrosis can be observed on the ovaria (Figs 20 and 21) accompanied by the involution of oviduct (Figs 22 and 23) and often amyloidosis of liver and spleen (Fig. 24). In case of stachybotryotoxicosis, smaller or larger areas are erythematous and oedematous and superficially necrotized on the head, wattle, neck (Fig. 26), as well as plantar pulp (Fig. 27)