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Resume Onze especes de Carnivores, appartenant aux familles principales (Canidae, Ursidae, Mustelidae, Hyaenidae, Felidae) ont ete retrouvees dans le materiel des fouilles recentes conduites par M. Faure et C. Guerin, confirmant pour l'essentiel la liste de J. Viret (1954) . De nombreuses donnees morphometriques viennent preciser les connaissances anterieures et des comparaisons sont tentees. La decouverte, rarissime, d'un crâne complet de Chasmaporthetes lunensis (= Euryboas lunensis, Hyaenidae) apporte un document exceptionnel. Une meilleure comprehension du site permet de preciser la paleoecologie des especes. L'enregistrement rigoureux dans l'espace des vestiges recueillis autorise une approche spatiale de la repartition de ces Carnivores dans les differentes lentilles d'accumulation, ce que facilitent le grand nombre d'especes et le faible nombre d'individus pour chacune.

A very rich assemblage of ancient brown bears (Ursus arctos arctos Linnaeus, 1758) from Mont Ventoux caves (France) has been investigated using carbon and nitrogen isotopic composition of bone collagen. The isotopic data showed that these bears were feeding in an open environment and consumed mainly plant food items. The access to livestock meat appeared to have been much more limited for these ancient brown bears than for 20th-century Pyrenean bears, suggesting that husbandry patterns had kept bears away from domestic herds. The isotopic variations observed are large according to the ontogenic stage of the bears when they died, which could be accounted for by the isotopic changes that occur during hibernation of the lactating female bear and by different time periods averaged in bone collagen, and without the need to involve different food resources for cubs relative to adult bears.

During the Upper Pliocene, two subspecies of Nyctereutes megamastoides (Pomel, 1842) — N. m. megamastoides and N. m. vulpinus — have been described in Western Europe. Nyctereutes megamastoides vulpinus Soria and Aguirre, 1976 was defined for the distinctive form of Saint-Vallier (Drome, France) to which was associated the remains from Puebla de Valverde (Teruel, Spain). Helped by the recent descriptions and identifications, especially the one of a pliocene species from China, Nyctereutes tingi Tedford and Qiu, 1991, the statut of the taxon from Saint-Vallier is revisited. We suggest that the Nyctereutes remains from this locality (excavation Viret in 1946–1956 and excavation Faure and Guerin in 1993–1999) and those from Puebla de Valverde should be referred to a distinct species, Nyctereutes vulpinus comb. and stat. nov.

Fertilin alpha (ADAM-1) and beta (ADAM-2) are integral membrane proteins of the ADAM family that form a fertilin complex involved in key steps of the sperm-oocyte membrane interaction. In the present work, we analyzed the presence of ADAM-1 and ADAM-2 mRNAs, the spermatozoa proteins' processing and their sub-cellular localization in epididymal samples from adult boars. ADAM-1 and ADAM-2 mRNAs were highly produced in the testis, but also in the vas efferens and the epididymis. On immunoblots of sperm extracts, ADAM-1 subunit appeared as a main reactive band of ~50-55 kDa corresponding to occurrence of different isoforms throughout the epididymal duct, especially in the corpus region where isoforms ranged from acidic to basic pI. In contrast, ADAM-2 was detected as several bands of ~90 kDa, ~75 kDa, ~50-55 kDa and ~40 kDa. The intensity of high molecular mass bands decreased progressively in the distal corpus where lower bands were also transiently observed, and only the ~40 kDa was observed in the cauda. The presence of bands of different molecular weights likely results from a proteolytic processing occurring mainly in the testis for ADAM-1, and also throughout the caput epididymis for ADAM-2. Immunolocalization showed that fertilin migrates from the acrosomal region to the acrosomal ridge during the sperm transit from the distal corpus to the proximal cauda. This migration is accompanied by an important change in the extractability of a part of ADAM-1 from the sperm membrane. This suggests that the fertilin surface migration may be triggered by the biochemical changes induced by the epididymal post-translational processing of both ADAM1 and ADAM-2. Different patterns of fertilin immunolocalization then define several populations of spermatozoa in the cauda epididymis. Characterization of such fertilin complex maturation patterns is an important step to develop fertility markers based on epididymal maturation of surface membrane proteins in domestic mammals.

The Balme à Collomb cave opens at an altitude of 1700 m, at the foot of the urgonian cliff of Mont Granier, in the Chartreuse massif. A great number of bones of Ursus spelaeus has been discovered there in a vergin gallery. 14C -AMS datings and biochronolo-gy (Rabeder method) tend to indicate a population of bears belonging to the Group 3 and to place it in the isotopic stage 3 (Middle Wurm). Paleoenvironmental data are given by palynology and some microfaunal remains. They both point to climatic periods of warming, however colder than today. An attempt of correlation with the GRIP 8 180 curve allows to wonder wether there had been a single occupation during the relatively long isotopic interstadial 8, or successive reconquest of the cave by the bears at every long enough climatic warming, during a long period (24 160 to > 45200 BP)., La Balme à Collomb est une grotte s'ouvrant à 1700 m d'altitude au pied de la falaise urgonienne du Mont Granier en Chartreuse. Elle a livré une grande quantité de restes d' Ursus spelaeus dans une galerie encore vierge. Les datations 14C -AMS et la biochronologie (méthode de Rabeder) indiquent une population du Groupe 3 occupant la grotte principalement au stade isotopique 3, au Wiirm moyen. Les données paléoenvironnementales de la palynologie, confirmées par un peu de microfaune traduisent une période d'amélioration climatique tempérée mais plus froide que l'actuelle. Une tentative de corrélation avec la courbe du 8 180 GRIP permet de poser la question d'une unique occupation sur la période suffisamment longue de l'interstade isotopique 8, ou d'une répétition de reconquête du milieu par les ours à chaque période d'amélioration climatique suffisante sur une très longue durée (24 160 à > 45200 BP)., Argant Alain, Argant Jacqueline. Datations et environnement des ours de la Balme à Collomb (Entremont-le-Vieux, Savoie, France). In: Cahiers scientifiques du Muséum d'histoire naturelle de Lyon. Hors-série, tome 2, 2004. Actes du 9e symposium international sur l'ours des cavernes.

Session 15: Postglacial recolonization patterns and mechanisms; Holocene small mammal communities at the north-western margin of continental Europe: some zooarchaeological considerations about the timing of post-glacial re-colonization. 6. European Congress of Mammalogy

International audience

L'étude d'un premier lot de parasites internes (Nematoda et Pentastoma) récoltés à l'autopsie de mammifères, oiseaux et reptiles de Haute-Casamance (Sénégal) a permis de signaler: Chez Varanus niloticus : Hastospiculum macrophollus (Parona 1889), Tauqua tiara (o.v. Linstow, 1879); chez Corocias naevius et C. abyssinicus : un Squamofilaria qui pourrait appartenir à l'espèce S. coronata (Rud. 1809); chez Meliarax metabates (faucon) : un Thelazia localisé à l'oeil. Chez Erythrocebus patas Schreber : Stryptopharagus pigmentatus (o. v. Linstow, 1897). Chez un singe vert (Cercopithecus aethiops var. sabaeus L. et sur Sylvicapra grimmia) : Protospirura muricola Gedoelst, 1918; chez Cercopithecus aethiops var. sabaeus et ichneumia aloicauda Cuv. (mangouste à queue blanche) : Les formes nymphales de Nettorhynchus (Armillifer) armillatus (Wyman, 1845) Pentastoma. Un second lot de nématodes comportant notamment un certain nombre de Physaloptera parasites de l'estomac des singes et des petits carnivores ainsi que des filaires d'oiseaux et de mammifères appartenant aux genres Diplotriaena Railliet et Henry, 1909, Setaria Wiborg, 1795, Dicrofilaria Railliet et Henry, 1911 est en cours d'étude et fera l'objet d'une note ultérieure

Les auteurs procèdent à l'autopsie d'une centaine de bovidés et suidés sauvages et identifient 47 espèces d'helminthes dont 26 spécifiques et 21 communes aux artiodactyles sauvages et domestiques (dont 13 très courantes, à large dispersion et fortement implantées dans le pays). Au Tchad et en R.C.A., les Artiodactyles sauvages ne paraissent pas - pour l'instant - représenter un danger certain pour les bovins, ovins, caprins ou camelins qui vivent à leur contact. Cependant, dans quelques cas - au demeurant limités - leur rôle ne doit pas être sous-estimé. Les auteurs signalent, en outre, que la Faune parasitaire des Bovidés et Suidés sauvages du bassin du Chari-Logone ne diffère pas fondamentalement de celle des bassins du Nil ou du Congo et de celle des pays d'Afrique de l'Est ou d'Afrique du Sud. L'action pathogène de ces Helminthes et l'importance des Associations parasitaires sont également envisagées

Background In vertebrates, late oogenesis is a key period during which the oocyte acquires its ability to resume meiosis (i.e. maturational competence) and to develop, once fertilized, into a normal embryo (i.e. developmental competence). However, the molecular mechanisms involved in these key biological processes are far from being fully understood. In order to identify key mechanisms conserved among teleosts and amphibians, we performed a comparative analysis using ovarian tissue sampled at successive steps of the maturational competence acquisition process in the rainbow trout (Oncorhynchus mykiss) and in the clawed toad (Xenopus laevis). Our study aimed at identifying common differentially expressed genes during late oogenesis in both species. Using an existing transcriptomic analysis that had previously been carried out in rainbow trout, candidate genes were selected for subsequent quantitative PCR-based comparative analysis. Results Among the 1200 differentially expressed clones in rainbow trout, twenty-six candidate genes were selected for further analysis by real-time PCR in both species during late oogenesis. Among these genes, eight had similar expression profiles in trout and Xenopus. Six genes were down-regulated during oocyte maturation (cyp19a1, cyp17a1, tescalcin, tfr1, cmah, hsd11b3) while two genes exhibited an opposite pattern (apoc1, star). In order to document possibly conserved molecular mechanisms, four genes (star, cyp19a1, cyp17a1 and hsd11b3) were further studied due to their known or suspected role in steroidogenesis after characterization of the orthology relationships between rainbow trout and Xenopus genes. Apoc1 was also selected for further analysis because of its reported function in cholesterol transport, which may modulate steroidogenesis by regulating cholesterol bioavailability in the steroidogenic cells. Conclusions We have successfully identified orthologous genes exhibiting conserved expression profiles in the ovarian follicle during late oogenesis in both trout and Xenopus. While some identified genes were previously uncharacterized during Xenopus late oogenesis, the nature of these genes has pointed out molecular mechanisms possibly conserved in amphibians and teleosts. It should also be stressed that in addition to the already suspected importance of steroidogenesis in maturational competence acquisition, our approach has shed light on other regulatory pathways which may be involved in maturational and developmental competence acquisitions that will require further studies.