Analysis of ultrastructural morphometric changes of pigeon kidneys affected by colibacteriosis

Abstract

Abstract. The article provides data on the morphometric changes in the kidneys of pigeons with colibacteriosis. Patho-morphological examination of the kidneys revealed focal hyperemia of the kidney cortical area and edema of the loose fibrous tissue. The convoluted renal tubule epitheliocytes were enlarged in size. In this case, the tubules get narrow and become slit-shaped. The convoluted tubules epithelium showed signs of granular dystrophy. In the chronic course of colibacteriosis, granuloma formation and signs of chronic interstitial nephritis were observed, in which the loose connective tissue of the cortical area is replaced by fibrous tissue. Morphometric analysis revealed that in the experimental group there was a decrease in the nephrocyte diameter (p= <0.05) to 98.06±0.46µm and the nephrocyte area to 6319.38±9.62µm. This results in a significant reduction (p= <0.05) of the sub-capsular space to 11.14±0.16µm compared to the control group. The distal and proximal convoluted tubules diameter also decreased to 127.43±20.78μm and 39.50±1.63μm, respectively. Accordingly, the area of the distal and proximal convoluted tubules decreased significantly (p= <0.05) to 10164.10±0.43µm and 2974.43±4.01µm, respectively. The patho-genetic effect of E. coli toxins revealed the renal tubular obstruction and slowing of the reabsorption and urinary excretion processes resulting in a reduction of glomerular filtration capacity of the kidney. Due to the prolonged course of salmonellosis occurring during the latent course, the area of renal filtration was also reduced. Accumulation of nitrogen metabolism products that enter the bloodstream caused impaired water-salt metabolism and acid-base equilibrium.