References of "Jauniaux, Thierry"
     in
Bookmark and Share    
See detailBrucella ceti infection in a harbor porpoise (Phocoena phocoena)
Jauniaux, Thierry ULg; Brenez, C.; Fretin, D. et al

in 9th Conference of European Wildlife Diseases Association (2010)

Detailed reference viewed: 14 (6 ULg)
Full Text
Peer Reviewed
See detailConcentrations of chlorinated and brominated contaminants and their metabolites in serum of harbour seals and harbour porpoises
Weijs, Liesbeth; Das, Krishna ULg; Siebert, Ursula et al

in Environment International (2009), 35(6), 842-850

Harbour seals (Phoca vitulina) and harbour porpoises (Phocoena phocoena) are top predators in the North Sea and consequently accumulate a variety of pollutants in their tissues. Concentrations of ... [more ▼]

Harbour seals (Phoca vitulina) and harbour porpoises (Phocoena phocoena) are top predators in the North Sea and consequently accumulate a variety of pollutants in their tissues. Concentrations of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and their hydroxylated metabolites (HO-PCBs and HO-PBDEs) were measured in serum of wild harbour seals (n=47) and captive harbour porpoises (n=21). Both species exhibit long life spans and do not have extreme situations, such as complete fasting during periods of lactation, in their annual cycles. For PCBs, concentrations in adult males were slightly higher than in juveniles and lowest in juvenile females. For PBDEs, juveniles have higher levels than adult males and females, probably as a consequence of lactational transfer. However. differences between these age-gender groups were not statistical significant, indicating that individual variation was limited within each species, even without knowing the feeding status of the animals. Body condition. particularly emaciation, has a major influence on the levels of chlorinated and brominated contaminants in serum. Profiles of PCBs were CB 153>CB 138>CB 187>CB 180 and CB 153>CB 138>CB 149>CB 187>CB 180 for harbour seals and porpoises respectively. For PBDEs, BDE 47 was the predominant congener followed by BDE 100 and 99 in both species. In harbour seals, concentrations of sum PCBs (median: 39,200 pg/ml) were more than 200 times higher than levels of sum PBDEs (median: 130 pg/ml) and almost 10 times higher than concentrations of sum HO-PCBs (4350 pg/ml). In harbour porpoises, concentrations of sum PCBs (median: 24,300 pg/ml) were about 20 times higher than concentrations of PBDEs (median: 1300 pg/ml). HO-PCBs were detected in only 4 harbour porpoises and this at very low concentrations. Naturally-produced MeO-PBDEs were only found in harbour porpoises at concentrations ranging from 120 to 810 pg/ml. HO-PBDEs were not found in any species. In general, harbour seals accumulate less compounds and have mostly lower concentrations than harbour porpoises possibly as a result of a better developed metabolism. (C) 2009 Elsevier Ltd. All rights reserved. [less ▲]

Detailed reference viewed: 94 (11 ULg)
See detailThe Belgian Marine Mammal Biobank: a tool to stimulate tissue exchange
Jauniaux, Thierry ULg; De Cauwer, Karien; De Winter, Johan et al

in Annual report (2009)

Detailed reference viewed: 28 (3 ULg)
Full Text
Peer Reviewed
See detailDecalcifying odontocete ears following a routine protocol with RDO (R)
Morell, M.; Degollada, E.; Alonso, J. M. et al

in Journal of Experimental Marine Biology & Ecology (2009), 376(2), 55-58

The study of the organ of Corti is essential to assess the impact of underwater noise on cetaceans. While classical histology techniques (including EDTA decalcification) have been previously considered ... [more ▼]

The study of the organ of Corti is essential to assess the impact of underwater noise on cetaceans. While classical histology techniques (including EDTA decalcification) have been previously considered, the process is time consuming. Independently from the histological technique, one of the challenging steps after extraction and fixation of the samples is to decalcify the bone envelope to access the cochlea without damaging the soft tissues. Here, we propose to use a fast commercial decalcifier (RDO (R)). 93 ears from 11 different odontocetes species stranded in the Mediterranean, Spanish North Atlantic and North Sea were used to precisely determine the decalcification time. Depending on the tympanic-periotic volume of the species, the decalcification time ranged from several hours to a few days, allowing a subsequently faster observation of the cochlear structures through routine microscope techniques. (C) 2009 Elsevier B.V. All rights reserved. [less ▲]

Detailed reference viewed: 26 (1 ULg)
Full Text
Peer Reviewed
See detailCauses of death of harbor porpoises (Phocoena phocoena) stranded on the coasts of Belgium and Northern France
Jauniaux, Thierry ULg; Stekke, V.; Coignoul, Freddy ULg

in Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Veterinary Medicine (2009), 66(2), 392

Detailed reference viewed: 14 (7 ULg)
Full Text
Peer Reviewed
See detailHarbour porpoise thyroids: Histological investigations and potential interactions with environmental factors
Schnitzler, Joseph ULg; Siebert, Ursula; Jepson, Paul et al

in Journal of Wildlife Diseases (2008), 44

The thyroid plays an important role in development and is of primary importance in metabolism and heat loss for cetaceans, including the harbor porpoise (Phocoena phocoena). Several studies have ... [more ▼]

The thyroid plays an important role in development and is of primary importance in metabolism and heat loss for cetaceans, including the harbor porpoise (Phocoena phocoena). Several studies have demonstrated that environmental contaminants can alter various aspects of thyroid function in mammals and may contribute to various histologic changes. The present study completes the data set of a 2006 study by Das et al., by performing histological and immunohistologic investigations on thyroids of 36 harbor porpoises from Belgian and United Kingdom waters. The number and mean diameter of follicles (µm) and the relative proportion of follicular, connective, and vascular tissue (%) were quantified in the thyroid gland of each individual. Interfollicular fibrosis has been observed in these thyroid glands, and the collective findings support the hypothesis of an endocrine disruption of thyroid function through organochlorinated compounds. Our study aimed also to reveal potential relationships between thyroid morphometric data and metal levels (Cd, Fe, Zn, Cu, Se, and Hg) using multivariate statistical analysis. The multiple regressions revealed statistically significant relationships between trace elements (cadmium, selenium, and copper) and thyroid fibrosis. The largely negative relationships are interesting findings but do not support the hypothesis that these elements have an adverse effect on thyroid morphometry. Further research is needed to understand the nature of any relationship between organochlorine and trace element exposure and thyroid gland morphology and function in harbor porpoises. [less ▲]

Detailed reference viewed: 142 (45 ULg)
Full Text
Peer Reviewed
See detailBluetongue in European lynx (Lynx lynx)
Jauniaux, Thierry ULg; De Clercq, Kris E.; Cassart, Dominique ULg et al

in Emerging Infectious Diseases (2008)

Detailed reference viewed: 32 (3 ULg)
Full Text
Peer Reviewed
See detailDioxin-like compounds in porpoises and seals from the southern North Sea: relationship with biological and ecological factors
Das, Krishna ULg; De Pauw, Edwin ULg; Eppe, Gauthier ULg et al

in Organohalogen Compounds (2008), 70

The North Sea represents a major ecosystem for the harbour porpoise (Phocoena phocoena) and the harbour seal (Phoca vitulina). The grey seal (Halichoerus grypus) occurs more occasionally in the southern ... [more ▼]

The North Sea represents a major ecosystem for the harbour porpoise (Phocoena phocoena) and the harbour seal (Phoca vitulina). The grey seal (Halichoerus grypus) occurs more occasionally in the southern part of the North Sea. Their population over this last decade has experienced major fluctuations likely linked to prey availability and seal epizootics. Despite being banned more than 30 years ago, levels of polychlorinated biphenyls (PCBs) in marine mammals are still of concern due to historical contamination of the North Sea. [less ▲]

Detailed reference viewed: 35 (6 ULg)
Full Text
Peer Reviewed
See detailBioaccumulation of persistent organic pollutants in female common dolphins (Delphinus delphis) and harbour porpoises (Phocoena phocoena) from western European seas: geographical trends, causal factors and effects on reproduction and mortality
Pierce, G. J.; Santos, M. B.; Murphy, S. et al

in Environmental Pollution (2008), 153(2), 401-415

female common dolphins and harbour porpoises from the Atlantic coast of Europe were frequently above the threshold at which effects on reproduction could be expected, in 40% and 47% of cases respectively ... [more ▼]

female common dolphins and harbour porpoises from the Atlantic coast of Europe were frequently above the threshold at which effects on reproduction could be expected, in 40% and 47% of cases respectively. This rose to 74% for porpoises from the southern North Sea. PCB concentrations were also high in southern North Sea fish. The average pregnancy rate recorded in porpoises (42%) in the study area was lower than in the western Atlantic but that in common dolphins (25%) was similar to that of the western Atlantic population. Porpoises that died from disease or parasitic infection had higher concentrations of persistent organic pollutants (POPs) than animals dying from other causes. Few of the common dolphins sampled had died from disease or parasitic infection. POP profiles in common dolphin blubber were related to individual feeding history while those in porpoises were more strongly related to condition. High PCB levels were recorded in porpoises and common dolphins from European coasts. [less ▲]

Detailed reference viewed: 24 (0 ULg)
Peer Reviewed
See detailHarbour porpoises stranded on the Dutch coast in 2007: Impact of by cath and related lesions
Grondin, Alexia; Camphuysen, K.; Ghisbain, T. et al

Poster (2008)

Detailed reference viewed: 22 (1 ULg)
Peer Reviewed
See detailCauses of death of harbor porpoises (Phocoena phocoena) stranded on the Dutch coast
Jauniaux, Thierry ULg; Bergerie, H.; Camphuysen, K. et al

in proceeding of the annual conference (2008)

Detailed reference viewed: 15 (1 ULg)
See detailRehabilitation of oiled marine mammals: an assessment
Jauniaux, Thierry ULg

in Meeting report (2008)

Detailed reference viewed: 11 (1 ULg)
Full Text
Peer Reviewed
See detailRise of oceanographic barriers in continuous populations of a cetacean: the genetic structure of harbour porpoises in Old World waters
Fontaine, Michaël C. ULg; Baird, Stuart J. E.; Piry, Sylvain et al

in BMC Biology (2007), 5

BACKGROUND: Understanding the role of seascape in shaping genetic and demographic population structure is highly challenging for marine pelagic species such as cetaceans for which there is generally ... [more ▼]

BACKGROUND: Understanding the role of seascape in shaping genetic and demographic population structure is highly challenging for marine pelagic species such as cetaceans for which there is generally little evidence of what could effectively restrict their dispersal. In the present work, we applied a combination of recent individual-based landscape genetic approaches to investigate the population genetic structure of a highly mobile extensive range cetacean, the harbour porpoise in the eastern North Atlantic, with regards to oceanographic characteristics that could constrain its dispersal. RESULTS: Analyses of 10 microsatellite loci for 752 individuals revealed that most of the sampled range in the eastern North Atlantic behaves as a 'continuous' population that widely extends over thousands of kilometres with significant isolation by distance (IBD). However, strong barriers to gene flow were detected in the south-eastern part of the range. These barriers coincided with profound changes in environmental characteristics and isolated, on a relatively small scale, porpoises from Iberian waters and on a larger scale porpoises from the Black Sea. CONCLUSION: The presence of these barriers to gene flow that coincide with profound changes in oceanographic features, together with the spatial variation in IBD strength, provide for the first time strong evidence that physical processes have a major impact on the demographic and genetic structure of a cetacean. This genetic pattern further suggests habitat-related fragmentation of the porpoise range that is likely to intensify with predicted surface ocean warming. [less ▲]

Detailed reference viewed: 29 (7 ULg)