Silicate pneumoconiosis in hens.

Thirteen cases of silicate pneumoconiosis in 3- to 4-year-old hens are described. Ten of the birds were raised in the suburbs of a city near several chalk quarries and two cement-works; the remaining three hens (aged 3 years) had lived in an environment with high particulate pollution from a nearby brick-works in which large amounts of clay were used daily. Silicotic granulomas composed of dust-laden macrophages were scattered over the lungs. They were located mainly in the infundibula and atria of tertiary bronchi and around vessels; more rarely they occurred in the lamina propria mucosae of primary and secondary bronchi. Energy dispersive x-ray microanalysis coupled with both transmission and scanning electron microscopy revealed that the dust was composed mainly of silicon, aluminium, calcium, iron and potassium. Titanium, sulphur, magnesium, zinc, copper and chlorine were also found. It is concluded that animals raised in polluted environmental conditions may serve as an important indicator of risks to human health and pathogenetic mechanisms. Thirteen cases of silicate pneumoconiosis in 3- to 4-year-old hens are described. Ten of the birds were raised in the suburbs of a city near several chalk quarries and two cement-works; the remaining three hens (aged 3 years) had lived in an environment with high particulate pollution from a nearby brick-works in which large amounts of clay were used daily. Silicotic granulomas composed of dust-laden macrophages were scattered over the lungs. They were located mainly in the infundibula and atria of tertiary bronchi and around vessels; more rarely they occurred in the lamina propria mucosae of primary and secondary bronchi. Energy dispersive x-ray microanalysis coupled with both transmission and scanning electron microscopy revealed that the dust was composed mainly of silicon, aluminium, calcium, iron and potassium. Titanium, sulphur, magnesium, zinc, copper and chlorine were also found. It is concluded that animals raised in polluted environmental conditions may serve as an important indicator of risks to human health and pathogenetic mechanisms. Copyright 2000 Harcourt Publishers Ltd.