THE IMPACT OF CADMIUM CHLORIDE ON THE GONADAL MORPHOLOGY OF THE NORTH AMERICAN BULLFROG TADPOLES, Lithobates catesbeianus (Shaw, 1802) (original) (raw)
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The present study was carried out to evaluate the sublethal effect of cadmium chloride in the ovaries of the airbreathing fish, Heteropnuestes fossilis which were kept in aqueous solution of cadmium chloride of two sublethal concentrations of 6mg/l and 9mg/l for 15, 30 and 45 days. The histopathological effect of CdCl 2 in ovaries is characterised by enlarged oocytes after 15 days of 6 mg/l exposure and degeneration of egg envelope after 30 days. After 45 days the atretic follicles appeared and nucleoi got scattered. In 9 mg/l concentration after 15 days, ovary wall got slightly thin and ruptured whereas enlarged interfollicular spaces were observed after 30 days and after 45 days egg envelopes got degenerated.
The present study was carried out to evaluate the sub-lethal effect of Cadmium chloride in the testis of the air-breathing fish, Heteropneustes fossilis which were kept in aqueous solution of Cadmium chloride of two sub-lethal concentrations of 6mg/l and 9mg/l for 15, 30 and 45 days. The histo-pathological effect of Cadmium chloride in testis is characterized by regression after 15 days of 6mg/l exposure and spermatozoa in the lobules showed cytolysis after 30 days. After 45 days the seminiferous tubules get vacuolated and dilated. In 9mg/l concentration after 15 days, the components of testicular architecture disorganized and germinal epithelium was disrupted, whereas seminiferous tubules get vacuolated after 30 days and after 45 days extensive damage to germinal epithelium, necrotic cells, connective tissues and atrophic and prominent vacoulation was recorded. Key words: Toxicity, Heavy metals, Cadmium chloride, Heteropnuestes fossilis.
Scientific Reports
Proper reproduction depends on properly functioning gonads (ovaries and testes). Many xenobiotics, including heavy metals, can cause changes in somatic and germ line cells, thus damaging the reproductive capacity. The aim of this study was to investigate the effect of the heavy metal cadmium on the gonads, including germ line and somatic cells. It is important to determine whether cell death processes are triggered in both types of cells in the gonads, and which gonads are more sensitive to the presence of cadmium in the environment. The research was conducted on the soil-dwelling arthropod Lithobius forficatus (Myriapoda, Chilopoda), which is common for European fauna. Animals were cultured in soil supplemented with Cd for different periods (short- and long-term treatment). Gonads were isolated and prepared for qualitative and quantitative analysis, which enabled us to describe all changes which appeared after both the short- and long-term cadmium treatment. The results of our stud...
Cadmium impairment of reproduction in the female wall lizardPodarcis sicula
Environmental Toxicology, 2011
The exposure to environmental toxicants such cadmium (Cd) is an important research area in wildlife protection. In this study, the effect of Cd oral administration on the ovarian structure and function and on reproductive performance of the Italian wall lizard Podarcis sicula was studied. In vivo, adult female lizards were randomly assigned to three groups. Cd was given with food in single dose and in multiple doses 3 days/week for 4 weeks at dose of 1.0 lg/g body weight. Following euthanasia, the ovaries were removed and analyzed for morpho-functional changes. Results demonstrated that Cd increases prefollicular germ cells number; the evaluation of the number of follicles detects significantly higher number of atretic growing follicles, whereas primary follicles remain unchanged with respect to controls. After Cd treatments, follicles are deformed by the presence of large protrusions and a general dysregulation in the follicle organization is observed. The zona pellucida is also affected. Cd causes alteration in sugar metabolism and in metallothionein gene expression. Finally, Cd administration significantly reduces clutch size and dramatically increases embryo mortality. In conclusion, data here described show that Cd induces morpho-functional alterations in lizard follicles and indicates that these are responsible for a significant impairment of oogenesis. The effects of the dose are time independent, persisting essentially unchanged regardless of single or multiple administration, so it can be concluded that even occasional, sublethal Cd contamination may significantly impair reproductive performance in these animals.
Estradiol Uptake, Toxicity, Metabolism, and Adverse Effects on Cadmium-Treated Amphibian Embryos
Environmental Health Perspectives, 2004
The exposure of Bufo arenarum embryos to 25 µmol/L 17β-estradiol (E 2 ) resulted in 100% lethality within 48 hr, whereas 10 µmol//L E 2 was the no observed effect concentration value for shortterm chronic (7 days) exposure. The toxicity profile curves show that lethal effects were proportional to the E 2 concentration and the time of exposure. The E 2 uptake resulted in 20.1 ng E 2 /mg embryo at 8 hr posttreatment, but 67.3% of this value was achieved during the first 30 min of incubation with this estrogen. Regarding metabolism, the embryos synthesize estrone (E 1 ) from E 2 by means of 17β-hydroxysteroid dehydrogenase. Simultaneous treatments of Bufo arenarum embryos with 1 mg/L Cd 2+ and 0.1, 1, or 10 µmol/L E 2 enhanced the lethality exerted by cadmium in 76.7, 80, and 83.3% of embryos, respectively. The results indicate that estrogenic endocrine disruptors could have an adverse effect on amphibian embryos and enhance the toxic effect of Cd on amphibian embryos. This study points to the possibility of using the AMPHITOX test as a screening method for potential endocrine disruption as well as the combined effects of chemical mixtures.
Evolution of cadmium effects in the testis and sperm of the tropical fish Gymnotus carapo
Tissue & cell, 2015
The present study investigated the testis and sperm morphology of the tropical fish Gymnotus carapo after exposure to increasing CdCl2 concentrations (5-40μM) for 24 and 96h. The treatments induced Cd accumulation in the testis and a decrease in the gonadosomatic index from a 10μM. Cd induced alterations in testis since 24h; however the extension and severity of damages increased after 96h in all tested concentrations. Marked variations in the cysts size, proliferation of the interstitial tissue, infiltration of inflammatory cells, necrosis, reduction of germ cells and sperm aggregation was observed in 96h treated fishes. In this time, there was a complete absence of germ cells in the testis of fish treated with 40μM. The ultrastructural analysis allowed for the visualization of the initial damages over germ cells, such as the presence of vacuoles in the cytoplasm of spermatogonia, spermatocytes, and spermatids. Exposed fish (20μM for 24 and 96h) had alterations in sperm number and ...
Toxicological Sciences, 2008
Xenopus laevis were exposed to 0-855 mg cadmium (Cd)/l (measured concentrations) in FETAX medium from fertilization to 47 days postfertilization. Measurements included embryonic survival and, at 47 days, tadpole survival, snout-vent length, tail length, total length, hindlimb length, weight, Nieuwkoop-Faber (NF) stage of development, initiation of metamorphic climax (‡ NF 58), and thyroid follicle cell height. Embryonic and larval survival were unaffected by Cd. Relative to control tadpoles, reduced tail and total length were observed at 0.1-8 and at 855 mg Cd/l; and reduced snout-vent length, hindlimb length, and weight were observed at 0.1-1 and at 855 mg Cd/l. Mean stage of development and rate of initiation of climax were unaffected by Cd at 0-84 mg/l; however, none of the tadpoles exposed to 855 mg Cd/l progressed beyond mid-premetamorphosis (NF 51). Thyroid glands with fully formed follicles were observed in all tadpoles ‡ NF 49 examined. Follicle cell height was unaffected by Cd at 0-84 mg/l but it was reduced at 855 mg/l; in the latter, cell height was reduced even when compared with NF 49-51 tadpoles pooled from the 0 to 84 mg Cd/l groups. In conclusion, (1) Cd affected tadpole growth in a bimodal pattern with the first and second inhibitory modes at concentrations below and above 84 mg Cd/l, respectively; (2) exposure to high Cd concentrations (855 mg/l) reduced thyroid activity and arrested tadpole development at mid-premetamorphosis; and (3) unlike its effect on growth, Cd inhibited tadpole development and thyroid function in a seemingly monotonic pattern.
Cadmium pollution and amphibians – Studies in tadpoles of Rana limnocharis
Chemosphere, 2016
h i g h l i g h t s • Cadmium caused concentration and time dependent mortality in Rana limnocharis tadpoles. • Cadmium reduced the time to metamorphosis in R. limnocharis. • The body weight at metamorphosis decreased while body length increased following cadmium exposure in R. limnocharis. • Cadmium caused chromosome and DNA damage in R. limnocharis.
Sublethal Effects of Cadmium Chloride to Testis of Zebrafish (Danio rerio)
2016
Cadmium (Cd) is one of the most toxic environmental heavy metals to organisms. The prominent toxic effects of Cd on reproductive organs are very well known. Gonad histopathology is a valuable tool for the assessment of endocrine disruption compounds EDCs effects on fish. The aim of this study was to evaluate the reproductive toxicity of cadmium chloride (CdCl2) on histopathology of Zebrafish (Danio rerio) testis under sub-lethal conditions. Male Zebrafish were exposed to four concentrations of CdCl2 (0.002,0.02, 2, and 20 mg/L) for 21 days in semi-static conditions. Histopathological changes in testis and Gonad Somatic Index (GSI) were studied. Treatment at 0.002 to 20 mg/L cadmium had no significant effect on the survival and condition factor. GSI decreased in a dosedependent manner and the decrease was significant (P < 0.001) in the group that received the highest dose. Testis histological alteration consisted of reduced testicular size, blood–testis barrier (BTB) disruption, g...
Marine Pollution Bulletin, 1999
Eects of cadmium on the fertilizing capability of spermatozoa, dynamics of the ®rst cleavage and pluteus formation in the sea urchin, Anthocidaris crassispina, were investigated. Exposure to cadmium concentrations of 0.32, 0.56, 1.0, 1.8, 3.2, 5.6 and 10.0 mg l À1 for 30 min caused a signi®cant adverse eect on the fertilizing capability of spermatozoa (EC 50 1.7 mg l À1 ). For the ®rst cleavage kinetics assay, eggs were pre-exposed to 0, 0.18, 0.32, 0.56, 1.0, 1.8, 3.2 and 5.6 mg l À1 of cadmium for 30 min. Fresh sperms of ®xed concentrations were then added to the eggs and the percentage of divided zygotes estimated. Concentration-dependent toxic eects on the dynamics of the ®rst cleavage in A. crassispina were observed between 0.18 and 5.6 mg l À1 cadmium. Calculation of EC 50 values by probit analysis at dierent stages of the ®rst cleavage revealed that EC 50 values increased gradually from 0.37 mg l À1 at the beginning to 2.24 mg l À1 at the end of the cleavage process. Dierent larval classes (normal, abnormal and retarded plutei, preplutei, dead embryos/larvae) of A. crassispina obtained from eggs pretreated with cadmium for 30 min and then exposed to cadmium throughout embryogenesis were also examined. The percentage of abnormal plutei was signi®cantly higher than that of the control at 0.56 mg l À1 cadmium and higher. The 48 h EC 50 calculated for the number of normal plutei was 1.5 mg l À1 . A v 2 -test revealed signi®cant changes in the distribution of proportions of dierent larval classes only at cadmium concentrations b 1.8 mg l À1 . At 5.6 mg l À1 of cadmium, small malformed plutei, and oval embryos with rudimentary skeleton, poorly differentiated intestines and no mouth (pre-pluteus stage) were observed. The relative sensitivity of various end points to cadmium is also compared and discussed. Ó