COMBINED AND SEPARATE EFFECTS OF HEAVY METALS ON ENERGY BUDGET AND METAL BALANCES IN ACHETA DOMESTICUS

Heavy metals are highly mobile within the invertebrate food web. To date, uptake in herbivo ous insects in relation to their feeding has not been studied intensively. The aim of this stud was therefore to examine the effects of Cd, Pb and Zn-contaminated food on parameters of the energy budget and energetic efficiencies of the house cricket, Acheta domesticus. The study w carried out on pre-last and last larval stages of male and female crickets. Both gravimetrica respirometric techniques were used in studying their energy budgets. The concentration of metal was measured in the diet, faeces and in insects. In almost all of the distinguished groups the was a significant decrease of food consumption and reduced digestibility in conparison wit control insects. Energetic costs of maintenance in metal-treated insects of the last larval instal were also lower than control. Similar data were stated, however, insignificant for the previous stage. Changes in the efficiency of gross and net production were not clearly correlated with the concentration of metals in the food or in the insects. In groups fed with the surplus of Cd. Pb or Zn, the concentration of metals was the highest in the last larval stage. Increased accumulation of metals in the body was negatively correlated with the energy content of the body Toxic effects of cadmium or lead seemed to be weaker when acting concomittant with zinc, as they were both more effectively removed from the body and their cumulation rate Was lesser than stated in insects fed on the diet contaminated by a single metal

The development al potential of the embryos of wolf spider Xerolycosa nemoralis from areas variously burdened with metals

The aim of this study was to assess and describe the developmental potential of the embryos of the wolf spider X. nemoralis collected from the reference site (Pilica) and a site heavily polluted with metals (Welnowiec) (southern Poland). For the analyses of the progress of development the embryos the computer microtomography was used. Adenylate concentration was measured using luminometric method. The macroscopic observations of the development of individual embryos revealed significant differences in the duration of embryogenesis (14,5 ±0.5 days in Pilica vs 16.5±0.53 in Welnowiec). The computer microtomography analyses enabled us to describe the geometry of the eggs inside the cocoon as well as to see the morphology of embryos inside the cocoon and to recognize selected developmental stages of the embryos. The concentration of cadmium in embryos in Welnowiec was significantly lower than in the embryos from the reference site, while the concentration of copper in the embryos from Pilica was significantly, 4 times lower than in Wełnowiec. The energy status indices (ATP concentration and ADP/ATP ratio) did not differ significantly in the embryos from the two sites

The development al potential of the embryos of wolf spider

The aim of this study was to assess and describe the developmental potential of the embryos of the wolf spider X. nemoralis collected from the reference site (Pilica) and a site heavily polluted with metals (Welnowiec) (southern Poland). For the analyses of the progress of development the embryos the computer microtomography was used. Adenylate concentration was measured using luminometric method. The macroscopic observations of the development of individual embryos revealed significant differences in the duration of embryogenesis (14,5 ±0.5 days in Pilica vs 16.5±0.53 in Welnowiec). The computer microtomography analyses enabled us to describe the geometry of the eggs inside the cocoon as well as to see the morphology of embryos inside the cocoon and to recognize selected developmental stages of the embryos. The concentration of cadmium in embryos in Welnowiec was significantly lower than in the embryos from the reference site, while the concentration of copper in the embryos from Pilica was significantly, 4 times lower than in Wełnowiec. The energy status indices (ATP concentration and ADP/ATP ratio) did not differ significantly in the embryos from the two sites