title: An observational study on changes in biometry and generation time of Odontophora villoti (Nematoda, Axonolaimidae) related to petroleum pollution in Bizerte bay, Tunisia.
abstract: BACKGROUND
  We conducted a yearly polluted-reference sampling to assess the effects of petroleum pollution on life cycle characteristics of the meiobenthic nematode Odontophora villoti. Samples were taken every 15 days between 26 November 2004 and 25 November 2005 from two beaches of Bizerte bay (Tunisia), Rimel and Tunisian Refining Industries Company (TRIC). The latter site is located in front of the "Tunisian Refining Industries Company" runoff.
  
  
  CONCLUSIONS
  When compared to the reference site, the mean body dimensions of O. villoti from the impacted site were significantly lower. The small size of affected nematodes was represented both by the length and width as a function of the life stage. It was also established that changes in lengths of body parts during molts were different between the two study sites. The low availability of oxygen from April to August seems to prevent the formation of embryos of O. villoti. Thus, two annual reproductive cycles with different durations were observed in Rimel and TRIC. Under stress, juvenile phase and egg production were generally shorter. Globally, the impact of petroleum pollution on O. villoti was expressed by a short egg-to-egg development time.
  
  
  CONCLUSIONS
  Our study assessed the usefulness of life cycle characteristics (biometry and life stage durations) of O. villoti in biomonitoring, and the results are generally consistent suggesting that this species may be considered as an efficient bioindicator.
authors: Coastal Ecology and Ecotoxicology Unit, Laboratory of Environment Biomonitoring, Faculty of Sciences of Bizerte, University of Carthage, 7021, Zarzouna, Tunisia. fehmiboufahja@yahoo.fr
authors: Fehmi
authors: F
authors: Boufahja
authors: Amor
authors: A
authors: Hedfi
authors: Naceur
authors: N
authors: Essid
authors: Patricia
authors: P
authors: Aïssa
authors: Ezzeddine
authors: E
authors: Mahmoudi
authors: Hamouda
authors: H
authors: Beyrem
mesh_terms: D000818:Animals; D001699:Biometry; D049628:Body Size / Q000187:drug effects; D004781:Environmental Exposure; D004784:Environmental Monitoring / Q000379:methods*; D019652:Extraction and Processing Industry; D005260:Female; D007814:Larva / Q000187:drug effects / Q000254:growth & development; D008018:Life Cycle Stages / Q000187:drug effects*; D008297:Male; D008522:Mediterranean Sea; D018978:Molting / Q000187:drug effects; D009348:Nematoda / Q000187:drug effects* / Q000254:growth & development*; D010058:Oviposition / Q000187:drug effects; D059392:Petroleum Pollution / Q000009:adverse effects*; D012098:Reproduction; D012621:Seasons; D013997:Time Factors; D014416:Tunisia; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity*
chemical_list: D014874:Water Pollutants, Chemical