Morphological and Pathological Effects of Cadmium Ingestion on Pekin Ducks Exposed to Saline

Abstract

This study examined the effects of simultaneous exposure to saline and cadmium (Cd) on organ mass and histology of a bird with salt glands, the Pekin duck, Anas platyrhynchos. Three mixed-sex groups, each containing 6 birds, ate duck pellets containing 0, 50, or 300 microg Cd/g, respectively, for 4 1/2 mo and drank 300 mM NaCl. Only females on the high-Cd diet lost body mass. Ingestion of Cd reduced heart mass in females. There was increased mass of Harderian and salt glands in both sexes. Mass of kidneys and liver increased only in males, and the gut mass (also length) increased more in males. Cadmium ingestion also induced (1) inflammation of renal interstitium and degenerative tubular changes, (2) marked degenerative changes in testes, (3) increased heart water content, (4) decreased cytoplasmic volume of liver cells, (5) reduced proportion of basophilic granular cells in chromaffin tissue of the adrenal glands, and (6) in the ileum, increased heterophilia in the lamina propria and, only in females, the apoptosis to mitosis ratio in crypt cells of the epithelium. The ducks' outward appearance gave no indication that ingesting large amounts of cadmium for 4 1/2 mo produced deleterious effects, but the physiological consequences were profound. Both sexes had greatly reduced gonadal mass and the males produced no sperm. The higher dietary level greatly hypertrophied the liver, kidneys, and gut only in males. The cadmium-induced changes in organs, particularly in the gonads, kidneys, and adrenal glands, should greatly impair the health and reproductive capacity of these ducks.

Effect of in ovo injection of cadmium on chicken embryo heart

“…Statistical analysis revealed that differences between the group of embryos exposed to 1 µg of cadmium and the control and sham groups was significant at 0.05, while differences between the control and sham groups and the group injected with 5 µg of cadmium were significant at 0.01 (Table 2). Similar changes in heart weight in female Pekin ducks exposed to cadmium were observed by Hughes et al (2000). A decrease in relative heart weight in broiler chickens receiving dietary cadmium was also described by Bokori et al (1996).…”

Evidence of species-specific detoxification processes for trace elements in shorebirds

“…The toxicity of this metal was previously demonstrated in vertebrates and birds in particular (Hughes et al 2000).…”

Impact of cadmium on aquatic bird Cairina moschata

“…Previous studies have shown an impact of cadmium on organs such as kidneys (Hughes et al 2000). These impairments have often been observed on very high contamination levels which are not relevant with concentrations found in natural environments or with Cd levels recorded in wild bird species.…”

“…For instance, in Alaska, very high levels of cadmium were reported in kidneys of Spectacled eiders (Somateria fischeri) (Trust et al 2000). These levels can lead to various effects on organisms such as the induction of inflammation of renal interstitium and marked degenerative changes in testes (Hughes et al 2000). However, few studies have focused on the possible impact of this non essential element on cellular metabolism of aquatic birds.…”