RESUMO
The effect of cadmium, with and without selenium, on breeding hens and cocks and their offspring up to 7 days of age was studied. In adult birds, the body weight, mortality rate, pathological changes and cadmium level were determined. In chicks, the mortality rate and level of cadmium were evaluated. Cadmium as cadmium chloride was orally administered to the hens at three dosages: 3 ppm, 20 ppm and 30 ppm + 4 ppm of selenium. Cadmium levels in the muscles, liver and kidneys of laying hens analysed after 60 days and those of chicks after 30 and 60 days of the experiment. Cd determinations were conducted by the method of electrothermic atomization, using an atomic absorption spectrophotometer. Body weight in laying hens was maintained at the control level, while in cocks it slightly increased in all experimental groups. In the adult birds, no mortality occurred while 0.25 - 1.11% mortality was observed in chicks. The results showed a variability in cadmium levels in hens, according to the dosage applied. These levels were high in the kidneys and liver, and lower in the muscles. A non-significant increase of cadmium level was found in the liver and kidneys of chicks after the first month of application. The addition of selenium resulted in a reduction of cadmium level in the liver and kidneys of laying hens but not in the muscles. Gross pathological and histological changes in the kidneys and liver were observed in groups fed 20 ppm and 30 ppm of cadmium.
