Bioaccumulation of some heavy metals and histopathological, ultrastructure alternation in kidney, brain and lung of migratory birds around Manzala Lake

الملخص EN

Migratory birds collected from September to March (2011-2012) from colonies on Lake of Manzala, in a variety of bird species, including mallards (Anas Platyrhynchos), pintails (Anas Acuta), teal (Anas Crecca) and coor (Atra Atra).

Immediately, heavy metals were measured in kidneys, liver and brain.

Results showed that heavy metals accumulations in birds tissue area under investigation were detected in following descending order: pb > Cd > Cu.

Carcasses were in good post mortum condition, the birds was moderately emaciated.

The spleen was mildly enlarged.

The intestine got darker, swollen, the tissues of liver and kidney were damaged and fragile.

The gross lesions mainly confined to the kidney which was dark or with haemorrhages and showed evidence of sever degeneration.

The kidneys showed sever degenerative changes which was more prominent in the cortex than the medulla.

The kidneys showed marked glomerular, tubular and interstitial pathological alternation.

Many glomeruli were shrunked with invaginated diffuse hyalinized thickening of capillary endothelium.

The tubules were dilated with accumulation of eosinophilic homogenous material in tubular lumina.

Necrobiotic changes with nuclear pyknosis Kayorrhexis, karyolysis, cytolysis, interstial odema and fibrosis were observed in the kidney.

Focal cellular necrosis was observed in the renal proximal tubule.

There was focal haemorrhagic area in between the renal tubules, dilatation and congestion of blood capillaries and PAS positive deposits focally spread in the mesangial matrix.

The tubule showed hyaline droplet degeneration and increased protein content by bromophenol blue stain.

Semithin section of kidney stained by toulidine blue showed heavy metals.

In the form of great number of dark granules in the apical sections of the tubular epithelial cell.

Ultrastructural findings of glomeruli demonstrated proliferation of mesangial cells.

Mitochondria in the cells showed some degree of swelling.

Nuclear inclusion bodies and large residual bodies were present.

The rough endoplasmic reticulum lost their characteristic arrangement.

Lysosomes were numerous in some cells.

Lysosomes in some cells contained dense bodies of varying sizes and large residual bodies were present.

Marked clumping of chromatin with the aggregation of interchromatin material at the center of the nucleus with intranuclear inclusions bodies.

Pericellular oedema, glioses or sattelosis in brain gray matter and demylenation or spongiosis in the white matter.

Chromatolysis of the nucleus and cytoplasmic vaculation in the neuron of the cerebral cortex.

Pulmonary congestion and the lung alveoli were markedly filled with erythrocytes.

The intealveolar blood cappilaries.

The lungs exhibited focal apoptosis at the apical portion of the cells and thickening of the interstitial connective tissue.