Abstract
A dangerous heavy metal that is non-degradable in the environment is cadmium (Cd). Many organs can accumulate cadmium, and adversely affect organ function and health. Cd is considered as a teratogenic and embryotoxic agent. This study aims to evaluate the teratogenicity of cadmium at concentrations lesser than the permissible and its effects on the heart during chick embryogenesis. Fertilized eggs of the chick Gallus domesticus were divided into; control, saline injected and four experimental groups injected with single doses of 5, 25, 50 or 75 µM of CdCl2. Histological observations of the heart before hatching and the cardiomyocytes after hatching were recorded. Morphometric measurements of heart chambers were achieved at 3, 4 and 6 days of incubation. Electrocardiograph and respiratory rate were recorded at tenth day. Different cardiac problems had been brought on by Cd. In comparison to controls, the heart looked to be much larger, and in certain cases, growth retardation was seen. Degeneration in heart walls and malformations of dorsal aorta were noticed. Morphomertrically, the width and wall thickness of heart chambers showed significant fluctuations between increase and decrease. Heart beats and respiratory rate significantly decreased compared to control. One of Cd toxicity is its ability to induce cellular oxidative stress. The heart in particular is very sensitive to oxidative stress. Cardiac oxidative stress might intensify heart failure and promote disease progression. Calcium is one of the components that needed for normal heart work. Cd might interfere with calcium metabolism by removing it from the body.