EFFECT OF SODIUM NITRATES AND NITRITES ON THE LIVER MORPHOLOGY IN BROILER CHICKS

Document Type : Research article

Authors

1 Fac. of Vet. Med. Dept. of Anatomy & Histology Head of the Dept. Prof. Dr. Aziza Abdel-Aziz

2 Dept. of Animal & Poultry Production, Fac. of Agriculture, University of Assiut

Abstract

The effects of a moderate increase in sodium nitrate and nitrite in drinking water (25% over the permissible level) on the liver morphology in newly hatched chicks were studied. A total of 180 one-day old newly hatched commercial meat-type unsexed chicks were used in a 6 weeks trail. Chicks were allocated to 3 treatments (control, sodium nitrate- and nitrite-treated groups) with three replicates (20 chicks each). At the end of the experiment, liver samples were collected from 4 chicks from each group and processed for both light and electron microscopy. The parenchyma of the liver of control chicks was generally composed of hexagonal shaped or polygonal hepatocytes arranged in hepatic laminae, each formed of two rows. Light and electron microscopy ascertained the accumulation of lipid droplets and/or globules as well as variably sized vacuoles within the cytoplasm of hepatocytes in treated groups, that were not detected in control group. Degenerative changes in many liver cells were recorded Additionally and on the ultrastructural level, deformity of the nuclear membrane and presence of degenerated cell organelles were observed. The morphometrical data showed that the area percent of lipid inclusions and vacuoles reached their highest value (6.4% of the liver parenchyma) after 4 weeks and declined afterwards in nitrite-treated group. On the other hand, the area percent of these inclusions and vacuoles were ill-measurable until the end of the fourth week in nitrate-treated group and became 3.28% of the liver parenchyma at the end of the experiment. In conclusion, small doses of nitrite and nitrate in drinking water (25% over the permissible level in water) leaded to moderate alteration in hepatocytes morphology that appeared quickly in nitrite treated group and decreased by prolonged treatment. Nitrate treatment resulted in mild effect on the liver parenchyma that started later than that observed in nitrite treatment.

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