title: Is reproductive effort environmentally or energetically controlled? The case of the Danube crested newt (Triturus dobrogicus).
abstract: Reproductive strategies have evolved from a series of trade-offs between cost and timing of reproduction. We tested whether the reproductive effort of female Danube crested newts, Triturus dobrogicus, was environmentally or energetically constrained. We collected females migrating towards the water and kept them separately, with males. Deposited eggs were collected daily during the experiment. More eggs were deposited by older females and by females starting to reproduce earlier. Batches of eggs from females depositing more eggs had a lower hatching success, suggesting decreased viability. Oviposition lasted on average 22.7 days. Female newts showed no loss of weight during this period. At the end of the egg deposition period we injected a subset of females with hormones that triggered the deposition of additional eggs. This suggests that egg deposition in Danube crested newts is environmentally constrained, as females stopped oviposition despite having mature eggs in their ovaries.
authors.affiliation: 1 University Ovidius Constanţa, Faculty of Natural Sciences, Al. Universităţii 1, corp B, 900470 Constanţa, Romania.
authors.forename: Dan
authors.initials: D
authors.lastname: Cogălniceanu
authors.forename: Elena
authors.initials: E
authors.lastname: Buhaciuc
authors.forename: Marian
authors.initials: M
authors.lastname: Tudor
authors.forename: Daniela
authors.initials: D
authors.lastname: Rosioru
mesh_terms: D000818:Animals; D004734:Energy Metabolism / Q000502:physiology*; D004777:Environment; D005260:Female; D005640:Follicle Stimulating Hormone / Q000494:pharmacology; D007986:Luteinizing Hormone / Q000494:pharmacology; D008297:Male; D012098:Reproduction / Q000187:drug effects / Q000502:physiology; D012455:Salamandridae / Q000502:physiology*
chemical_list: D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone