Europe's terrestrial biosphere absorbs 7 to 12% of European anthropogenic CO2 emissions

Most inverse atmospheric models report considerable uptake of carbon dioxide in Europe's terrestrial biosphere. In contrast, carbon stocks in terrestrial ecosystems increase at a much smaller rate, with carbon gains in forests and grassland soils almost being offset by carbon losses from cropland and peat soils. Accounting for non-carbon dioxide carbon transfers that are not detected by the atmospheric models and for carbon dioxide fluxes bypassing the ecosystem carbon stocks considerably reduces the gap between the small carbon-stock changes and the larger carbon dioxide uptake estimated by atmospheric models. The remaining difference could be because of missing components in the stock-change approach, as well as the large uncertainty in both methods. With the use of the corrected atmosphere- and land-based estimates as a dual constraint, we estimate a net carbon sink between 135 and 205 teragrams per year in Europe's terrestrial biosphere, the equivalent of 7 to 12% of the 1995 anthropogenic carbon emissions.     

Conservation priorities differ at opposing species borders of a European orchid

How populations from different regions within the distribution of a species contribute to the adaptive potential and survival of that species has important implications for formulating conservation actions. We test assumptions of concepts on geographic population structure (e.g. central-marginal concept and ‘rear edge versus leading edge’ model) that could be used to inform conservation of plant species under climatic changes. We analyze a comprehensive dataset of demographic traits (e.g. population size, flowering, δ¹³C of plant leaves) of up to 32 sites of Himantoglossum hircinum (L.) Spreng. (Orchidaceae) located within six sub-regions of its European distribution range. Soil and climate parameters are employed as environmental predictors of variation in measured population traits. Climate is the main driver of demographic variability overriding central-marginal gradients that might be present. Warming of the climate at high latitudes paves the way for northward range expansion of species. Populations at the north and north-eastern range peripheries partly show exponential population growth and high genetic diversity and are likely to be the source of immigrants for colonization of newly suitable habitats as the climate continues to change. In recent times, populations at the southern range periphery have suffered from intensification of land use and decreasing rainfall, but in the case of Southern Italy are important because they contain genetically unique traits. Populations at both, ‘leading’ and ‘rear’, edges ought to be at the focus of conservation planning. Different conservation strategies are proposed at opposing species borders taking into account spatial variation in population needs on a geographic scale, projected population response to expected environmental changes and genetic characteristics.     

Pansteatitis and severe hypocalcaemia in a cat

A 13-year-old Siamese cat was presented for investigation of lethargy and progressive abdominal enlargement. Serum chemistry revealed severe reduction of total and ionised serum calcium. The omentum appeared hyperechoic with scattered hypoechoic foci on abdominal ultrasound examination. Elevated serum parathormone and low fractional excretion of calcium excluded a parathyroid disorder and renal loss of the electrolyte. During laparotomy the omentum appeared opaque, white and firm. Post-mortem examination revealed that the thoracic and subcutaneous fat was also affected. Histopathology confirmed the diagnosis of pansteatitis with diffuse calcium soaps formation. While, severe hypocalcaemia is occasionally seen in cats, the association with pansteatitis has not been reported previously. In man, a cause-and-effect relationship between calcium soaps and hypocalcaemia is recognised, though the association is rare.     

Analysis of immune responses induced by avian pathogenic Escherichia coli infection in turkeys and their association with resistance to homologous re-challenge

Avian pathogenic Escherichia coli (APEC) cause severe respiratory and systemic disease in poultry yet the nature and consequences of host immune responses to infection are poorly understood. Here, we describe a turkey sub-acute respiratory challenge model and cytokine, cell-mediated and humoral responses associated with protection against homologous re-challenge. Intra-airsac inoculation of turkeys with 10⁵ colony-forming units of APEC O78:H9 strain χ7122nal^R induced transient and mild clinical signs of colibacillosis followed by clearance of the bacteria from the lungs and visceral organs. Upon re-challenge with 10⁷ χ7122nal^R, primed birds were solidly protected against clinical signs and exhibited negligible bacterial loads in visceral organs, whereas age-matched control birds exhibited high lesion scores and bacterial loads in the organs. Levels of mRNA for signature cytokines suggested induction of a Th1 response in the lung, whereas a distinct anti-inflammatory cytokine profile was detected in the liver. Proliferative responses of splenocytes to either Concanavalin A or soluble χ7122nal^R antigens were negligible prior to clearance of bacteria, but APEC-specific responses were significantly elevated at later time intervals and at re-challenge relative to control birds. Primary infection also induced significantly elevated χ7122nal^R-specific serum IgY and bile IgA responses which were bactericidal against χ7122nal^R and an isogenic Δrfb mutant. Bactericidal activity was observed in the presence of immune, but not heat-inactivated immune serum, indicating that the antibodies can fix complement and are not directed solely at the lipopolysaccharide O-antigen. Such data inform the rational design of strategies to control a recalcitrant endemic disease of poultry.     

Anovulation in postpartum suckled beef cows. I. Associations among size and numbers of ovarian follicles, uterine involution, and hormones in serum and follicular fluid

Changes in sizes and numbers of ovarian antral follicles, uterine size and weight, serum hormones, and frequency and duration of suckling were examined during the postpartum anovulatory period in primiparous, suckled beef cows. Twenty-one anovulatory, suckled cows (n = 4 to 6/d) were slaughtered on d 7, 14, 28 and 42 to 56 after parturition. In addition, a total of 11 postpartum cows that had begun cyclic activity were slaughtered on d 28, 42 or 56. Blood was collected at 10-min intervals for 6 h 1 d before slaughter for measurement of prolactin, cortisol and progesterone in serum. Numbers of medium (4.0 to 7.9 mm) follicles increased fourfold (P less than .05) between d 7 and 42 to 56 in anovulatory cows, whereas numbers of small (1.0 to 3.9 mm) and large (greater than or equal to 8.0 mm) follicles did not change (P greater than .10). Uterine involution was complete by d 28. In anovulatory cows, a higher (P less than .05) proportion of largest (but not second-largest) follicles was opposite the ovary containing the corpus albicans from pregnancy (CAP). In addition, 90% of these largest follicles opposite the CAP had concentrations of estradiol greater than progesterone. In cyclic cows, however, first ovulations occurred with equal frequency on either ovary. Concentrations of prolactin or cortisol in serum or duration of suckling were not associated with changes in uterine or ovarian measurements. In conclusion, growth and function of the largest (but not second-largest) follicle were reduced when located on the ovary containing the CAP.(ABSTRACT TRUNCATED AT 250 WORDS)     

Furunculosis-inducing ability of microcosms seeded with Aeromonas salmonicida correlates with colony-forming ability but not with PCR and ELISA data

Two laboratory microcosms, constructed of sterilised sediment and water taken from different locations, were seeded with Aeromonas salmonicida. A non-quantitative PCR, a heterogeneous, non-competitive, sandwich ELISA and colony formation were employed to generate survival data. In one microcosm, all three analytical methods generated positive results over the full 279 days of the incubation of the system at 18 °C. In the second microcosm, constructed with humic acid-rich material, colony formation was undetectable after 1 day but the PCR and ELISA methods generated positive results for up to 269 days.

Direct injection into fish of material from the two microcosms both seeded with a passaged strain of A. salmonicida was used to determine the disease-producing potential of the bacteria in these systems. A direct correlation was observed between the presence of colony-forming units and the ability to produce furunculosis in test fish. None of the samples that generated positive PCR and ELISA signals but in which colony formation was not detected proved capable of inducing disease in fish. The significance of these data for the application of proxy methods in epizootiological studies is discussed.     

Production of alpha 1,3-galactosyltransferase-deficient pigs

The enzyme alpha1,3-galactosyltransferase (alpha1,3GT or GGTA1) synthesizes alpha1,3-galactose (alpha1,3Gal) epitopes (Galalpha1,3Galbeta1,4GlcNAc-R), which are the major xenoantigens causing hyperacute rejection in pig-to-human xenotransplantation. Complete removal of alpha1,3Gal from pig organs is the critical step toward the success of xenotransplantation. We reported earlier the targeted disruption of one allele of the alpha1,3GT gene in cloned pigs. A selection procedure based on a bacterial toxin was used to select for cells in which the second allele of the gene was knocked out. Sequencing analysis demonstrated that knockout of the second allele of the alpha1,3GT gene was caused by a T-to-G single point mutation at the second base of exon 9, which resulted in inactivation of the alpha1,3GT protein. Four healthy alpha1,3GT double-knockout female piglets were produced by three consecutive rounds of cloning. The piglets carrying a point mutation in the alpha1,3GT gene hold significant value, as they would allow production of alpha1,3Gal-deficient pigs free of antibiotic-resistance genes and thus have the potential to make a safer product for human use.