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The Coniacian-Santonian stages in western North America are characterized by a sparse fossil record. We present here the first account of dinosaur tracks from nine sites in the Frontier Formation (Coniacian-Santonian) of southwestern Montana. Tracks are largely preserved in distal alluvial facies as sandstone casts, with a single example of shallow epirelief impression interpreted as undertrack. Sandstone casts show significant relief, kinematic features (i.e., scale marks), and variable morphologies, arguing for a strong substrate control on their preservation. Putative producers are assigned to ornithopod, ankylosaurian, and theropod dinosaurs in decreasing order of abundance. This record reflects a composition similar to those of other middle Cretaceous formations in North America. Moreover, ankylosaurian tracks of the Frontier Formation represent the first known from Coniacian strata in North America. The incorporation of body and trace fossils yielded by the Frontier Formation indicates the presence of a fauna with North American endemic elements. The establishment of Coniacian-Santonian dinosaurian palaeocommunities akin to those observed in Campanian and Maastrichtian formations may reflect the trend towards provincialism attested for the end of the Mesozoic in North America. [ABSTRACT FROM AUTHOR]

Farmland is a major land cover type in Europe and Africa and provides habitat for numerous species. The severe decline in farmland biodiversity of the last decades has been attributed to changes in farming practices, and organic and low-input farming are assumed to mitigate detrimental effects of agricultural intensification on biodiversity. Since the farm enterprise is the primary unit of agricultural decision making, management-related effects at the field scale need to be assessed at the farm level. Therefore, in this study, data were collected on habitat characteristics, vascular plant, earthworm, spider, and bee communities and on the corresponding agricultural management in 237 farms in 13 European and two African regions. In 15 environmental and agricultural homogeneous regions, 6-20 farms with the same farm type (e.g., arable crops, grassland, or specific permanent crops) were selected. If available, an equal number of organic and non-organic farms were randomly selected. Alternatively, farms were sampled along a gradient of management intensity. For all selected farms, the entire farmed area was mapped, which resulted in total in the mapping of 11 338 units attributed to 194 standardized habitat types, provided together with additional descriptors. On each farm, one site per available habitat type was randomly selected for species diversity investigations. Species were sampled on 2115 sites and identified to the species level by expert taxonomists. Species lists and abundance estimates are provided for each site and sampling date (one date for plants and earthworms, three dates for spiders and bees). In addition, farmers provided information about their management practices in face-to-face interviews following a standardized questionnaire. Farm management indicators for each farm are available (e.g., nitrogen input, pesticide applications, or energy input). Analyses revealed a positive effect of unproductive areas and a negative effect of intensive management on biodiversity. Communities of the four taxonomic groups strongly differed in their response to habitat characteristics, agricultural management, and regional circumstances. The data has potential for further insights into interactions of farmland biodiversity and agricultural management at site, farm, and regional scale. [ABSTRACT FROM AUTHOR]

Nitrite is toxic to fishes and is often encountered in recirculation aquaculture systems. The present study was carried out to study gills, liver and kidney histopathology in the juvenile freshwater fish Oncorhynchus mykiss which exposed to nitrite (1.2 ± 0.03 mg L-1) for 96 hours. Histopathological alterations in gills, liver and kidneys observed microscopically showed damage in the tissues while gills, liver and kidneys of control groups exhibited a normal architecture. The most characteristic features observed in nitrite exposed fish were hemorrhages in the oral cavity, in gills and on fish body surface; focal hemorrhages under the liver capsule and in the stratum of parenchyma; atrophy and destructive changes of hepatocytes; granular degeneration of liver and kidney; liver hyaline-drop dystrophy. The study confirmed that histopathological biomarkers of toxicity in fish organs are a useful indicator of environmental pollution. [ABSTRACT FROM AUTHOR]

The GH gene ofSparus aurata(saGH) contains variable number of tandem repeats(VNTR). The hyper-variable minisatellites in the first and third introns segregate in a Mendelian manner and exhibit numerous alleles. Analysis by PCR and sequencing of the two introns in several wild Sparidae species revealed comparable minisatellites with some variations.‘Zoo blot’ with the first intron unit as a probe showed this sequence to be characteristic of several families from the Perciformes order. Unexpectedly, a similar minisatellite was found in the first intron of the GH gene in flounder, which belongs to a different order. Transfection of constructs containing a reporter gene and first intron of different length to four cell lines resulted in an inhibitory effect of the longer intron relative to the short intron. A(CA)n microsatellite(saGHpCA) is found in the GH promoter. A similar repeat at the same location is present in GH promoters of several other fish species. High variability(11 alleles) of the saGHpCA was found in a hatchery population. Full-sib family genotyping showed a Mendelian inheritance of these alleles. A significant association was found between allele distribution and body mass in large and average size fishes from a hatchery population. The intron minisatellites may serve as markers for hybrid population and parental assignment. Its presence in families and orders of the higher teleosts may help solving classification uncertainties. Their conservation and inhibitory effect suggest a biological role. The saGHpCA is correlated with growth and may be a good candidate for predicting growth performance. [ABSTRACT FROM AUTHOR]

Abstract: The α2-macroglobulin proteinase inhibitors (α2Ms) are a family of plasma proteins with the unique ability to inhibit a broad spectrum of proteinases, but are also known as binding proteins for many growth factors and cytokines, including growth hormone and members of the transforming growth factor-β superfamily. A partial cDNA (475 amino acids) encoding the C-terminus of α2M was cloned from the liver of the marine teleostean fish Sparus aurata. The deduced amino acid sequence of the cloned fragment showed 58–60% similarity to carp α2Ms. Northern blot analysis of hepatic α2M revealed a transcript of about 5 kb. A transcript of a similar size was detected in 1-day larvae. Steady state levels of α2M in larvae increased gradually on subsequent days post-hatching. α2M expression in embryos was determined by RT-PCR and started in embryos aged 8 h post-fertilization, but not earlier. RT-PCR of muscle RNA detected α2M also in fish muscle, albeit with a lower expression than in the liver. Immunoreactive-α2M was found in yolk syncytial layer of 3-day larvae and in livers from larvae and adults. Immunoreactive-α2M was also identified in soluble total proteins from young larvae with a pattern resembling that of plasma. These data demonstrate that the α2M gene is expressed early in fish development. Moreover, in addition to its major expression in liver, α2M is expressed also in fish muscle. [Copyright &y& Elsevier]

The Coniacian non-marine portion of the Frontier Formation in southwestern Montana has been primarily studied stratigraphically, whereas its trace fossil record and relative sedimentological significance have remained overlooked so far. We present the first description of a trace fossil assemblage reported from Frontier Formation deposits exposed in the western Centennial Mountains, Beaverhead County, Montana. Three main lithofacies groups with distinctive trace fossil assemblages have been recognised at the locality of Price Creek: (1) coarse-grained, thin and laterally extensive cross-bedded sandstone channel bodies characterised by rare vertical, passively filled burrows; (2) fine-grained overbank sandstones and siltstones, with abundant horizontal, meniscated, and unwalled burrows, sinusoidal trails, vertical burrows, and dinosaur tracks, and (3) fining-upward, planar cross-bedded silty sandstones, associated with carbonaceous plant material and bone fragments. The trace fossil assemblage is ascribed to the pre-desiccation suit of the Scoyenia ichnofacies. The occurrence of theropod, ornithopod, and thyreophoran dinosaur tracks, and invertebrate trace fossils suggests considerable diversity of terrestrial and aquatic fauna. Tracks described here represent the first dinosaurian record reported from Coniacian deposits in Montana and one of the few fossil records reported from non-marine Coniacian deposits in North America. [ABSTRACT FROM AUTHOR]

The striped sea bream (Lithognathus mormyrus) has been recently introduced as a bioindicator fish species in Mediterranean coastal habitats. The purpose of this study was to apply a real-time PCR assay for the determination of absolute levels of hepatic VTG transcript in this fish, identifying minimal and maximal levels and establishing the relationship between VTG RNA levels and ovarian development. A partial VTG cDNA was cloned from hepatic RNA of a striped sea bream female. Specific primers were designed based on its sequence and used for PCR and also for in vitro synthesis of partial VTG RNA standard. Hepatic VTG transcript levels were quantified by real-time PCR, using serially diluted VTG RNA standards for construction of a calibration curve and equation. VTG RNA levels were normalized to total RNA or 18S ribosomal RNA (determined by real-time PCR). VTG RNA was hardly detected in the liver of males, or females with small oocytes (diameter < 100 microm). A linear correlation was found between these two parameters at larger oocyte diameter (> 150 microm). VTG level reached a maximum of 204 fmol/pmol 18S RNA or 49 fmol/microg RNA. The results demonstrate the wide dynamic range of the established real-time PCR assay.