title: The effect of ingested cadmium on the calorific value and structural properties of hunting webs produced by Steatoda grossa (Theridiidae) spiders.
abstract: The study aimed to assess whether cadmium administered via ingestion to Steatoda grossa cobweb spiders (Theridiidae) affects the energy content and selected structural properties of the produced hunting webs. Cadmium content in webs was assessed with AAS and SEM X-ray microanalysis, while the diameters of silk fibers were estimated with SEM. The energy content of samples was measured in an oxygen micro-bomb calorimeter. Females and males showed different reactions to cadmium supplied through food. In comparison to females, males displayed higher metal concentrations in their bodies and hunting webs, however their calorific values and structural features were not significantly changed. Cadmium-treated females spun webs with smaller single-strand diameters and more frequent multi-stranded threads and invested 47% less energy in web production than the control individuals. It cannot be excluded that such a reduction in energy expenditure for web building in females resulted from energetically costly detoxifying reactions triggered in response to direct and indirect effects of cadmium toxicity.
authors.affiliation: Department of Animal Physiology and Ecotoxicology, Faculty of Biology and Environmental Protection, University of Silesia, Bankowa 9, Katowice 40-007, Poland. Electronic address: grazyna.wilczek@us.edu.pl.
authors.forename: Grażyna
authors.initials: G
authors.lastname: Wilczek
authors.affiliation: Laboratory of Scanning Electron Microscopy, Faculty of Biology and Environmental Protection, University of Silesia, Jagiellońska 28, Katowice 40-007, Poland.
authors.forename: Jagna
authors.initials: J
authors.lastname: Karcz
authors.affiliation: Department of Animal Physiology and Ecotoxicology, Faculty of Biology and Environmental Protection, University of Silesia, Bankowa 9, Katowice 40-007, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Putko
authors.affiliation: Department of Animal Physiology and Ecotoxicology, Faculty of Biology and Environmental Protection, University of Silesia, Bankowa 9, Katowice 40-007, Poland.
authors.forename: Andrzej
authors.initials: A
authors.lastname: Kędziorski
authors.affiliation: Bioengineering Laboratory, Heart Prosthesis Institute FRK, Wolności 345a, Zabrze 41-800, Poland.
authors.forename: Piotr
authors.initials: P
authors.lastname: Wilczek
authors.affiliation: Department of Animal Physiology and Ecotoxicology, Faculty of Biology and Environmental Protection, University of Silesia, Bankowa 9, Katowice 40-007, Poland.
authors.forename: Monika
authors.initials: M
authors.lastname: Stalmach
authors.affiliation: Department of Animal Physiology and Ecotoxicology, Faculty of Biology and Environmental Protection, University of Silesia, Bankowa 9, Katowice 40-007, Poland.
authors.forename: Elżbieta
authors.initials: E
authors.lastname: Szulińska
mesh_terms: D000818:Animals; D002104:Cadmium / Q000633:toxicity*; D004435:Eating; D004734:Energy Metabolism; D005260:Female; D008297:Male; D011235:Predatory Behavior; D047011:Silk / Q000737:chemistry*; D013112:Spiders
chemical_list: D047011:Silk; D002104:Cadmium
keywords: Cadmium; Energy content; Spiders; Webs