Influence of Cadmium Chloride on the Indicators of Rat Embryogenesis in Intragastric Injection

There has been an expansion of using various cadmium compounds recently, which, together with a significant increase in the anthropogenic contribution to environmental contamination, has led to an excess of the maximum allowable concentration of cadmium in some regions of our country and abroad in water, air and food. In the scientific literature there is a significant number of works dealing with the study of this toxicant influence in the postnatal period of ontogenesis, while the influence of cadmium on embryogenesis has not been studied enough. The purpose of the study was the experimental determination of the effect of low doses of cadmium chloride on the overall course of embryogenesis in rats with intragastric administration. Material and methods. A low dose of cadmium salt was chosen for the study, which can be compared with the actual concentration in daily diets of women, including pregnant women, in the industrial region. The dose for cadmium chloride was 1.0 mg / kg body weight. According to the generally accepted instructions for carrying out the experimental work, a solution of cadmium chloride was administered to female rats enterally through the probe once a day, at the same time, from the first to the 19th day of pregnancy. During the solutions administration, we recorded the condition and behavior of females, the dynamics of body weight, rectal temperature, duration of pregnancy. We performed operative slaughter on the 13th and 20th days of pregnancy. The rats were withdrawn from the uterus, checked for a "live-dead" test, weighed, photographed and fixed in a 10% formalin solution for further histological examination. Determination of the possible embryotoxic effect of cadmium chloride was carried out by calculating standard indices of embryonic development: number of fetuses, total embryonic mortality, pre-implantation embryonic mortality, and post-implantation embryonic mortality on 13th and 20th days of rat embryogenesis. Results and discussion. The obtained results showed that in case of application the low doses of cadmium chloride, the average embryo count as compared to the control group on the 13th day of embryogenesis was reduced by 13.9% and on 20th day- by 14.8% (an average of 14.4%). This reduces not only the total number of fetuses, but also their mass and size in comparison with the control group, although without significant difference. The average index of the number of yellow bodies of pregnancy in the ovaries of females did not also have a significant difference, which does not contradict the literary scientific data. The greatest changes were observed in terms of total embryonic mortality, which grew from 4.58% in the control group to 18.81% in the cadmium chloride group. In the control group, preimplantation mortality was absent on the 13th day of development, and in the experimental group it was the highest. The total embryonic death rate increased with cadmium chloride intoxication by 4.1 times (p <0.01) due to overwhelming mortality in the preimplantation period. Conclusions. The obtained data indicate the embryotoxic effect of ultrasmall doses of cadmium chloride on experimental animals (rats) with intragastric administration of cadmium throughout the gestation period.