Development of a reference diet for use in indispensable amino acid requirement studies of gilthead seabream Sparus aurata L.

The development of a test diet supporting good fish growth to be used in gilthead seabream indispensable amino acid (IAA) requirement studies based on dose–response relationship was the objective of the present study. Four isonitrogenous diets, one serving as control (diet C) based on fish meal LT, and three others in which the fish meal component was reduced to 45% and the rest of the nitrogen was provided by mixtures of crystalline AA were formulated. Diet S resembled the whole body IAA profile of wild seabream. Diet D was made deficient in all IAA and a 10% excess of IAA compared with diet S was used in diet E. Triplicate groups of fish were fed the diets to satiation for 6 weeks. Growth parameters and nutrient utilization efficiencies among diets C and S were similar, while excessive supplementation of IAA negatively affected most of them, compared with the control. Whole body composition was differentiated in relation to the diet fed. No significant differences were observed among groups fed the control and diet S. As shown by the results, the presence of crystalline AA in diet S does not significantly affect growth, and could therefore serve as control diet in IAA requirement studies of gilthead seabream.     

Temperature-dependent pharmacokinetics and tissue distribution of oxolinic acid in sea bass, Dicentrarchus labrax L., after a single intravascular injection

The pharmacokinetics and tissue distribution of oxolinic acid following an intravascular administration (15 mg kg^?1 fish) were determined in sea bass, Dicentrarchus labrax L. (110 g), at 13 °C and 22 °C water temperature. The kinetic profile of the drug was found to be temperature dependent, with increased temperature having a greater effect on distribution after equilibrium and the elimination phase than on the distribution process. The distibution half‐life of oxolinic acid was 1.15 and 2.76 h at 22 °C and 13 °C respectively, whereas the elimination half‐life of the drug was 55 h at 22 °C and 315 h at 13 °C. The values of the apparent volume of distribution (1.44 L kg^?1 at 22 °C and 3.31 L kg^?1 at 13 °C) and the volume of distribution at steady state (5.2 and 14.7 L kg^?1 at the high and low temperature respectively) were considerably different between the two tested temperatures. The total body clearance of the antibiotic was found to be low (1.47 L kg^?1 day^?1 at 22 °C and 0.80 L kg^?1 day^?1 at 13 °C). Lower rates of elimination were found for the liver compared with muscle, the difference increasing with increasing temperature, while elimination rates from the serum were higher than those of other tissues, especially at the high temperature.     

Effects of Fish Meal Replacement by a Soybean Protein on Growth,Histology, Selected Immune and Oxidative Status Markers of Gilthead Sea Bream,Sparus aurata

The purpose of the trial was to study the impact of a 6‐mo dietary administration of soybean protein on growth, liver and intestine morphology, immune response, and oxidative stress in gilthead sea bream. The immune response was evaluated by performing immunological assays in blood, head kidney (HK), or serum (respiratory burst activity [RBA], myeloperoxidase content and bacteriolytic activity) and gene expression analysis of immune‐associated genes (MHCIIα [major histocompatibility complex IIα], β2m [β‐2‐microglobulin], CSF‐1R [colony‐stimulating factor‐1 receptor], NCCRP‐1 [nonspecific cytotoxic cell receptor protein 1], TGF‐β1 [transforming growth factor beta‐1], and HSP70 [heat‐shock protein 70]) in HK and intestine. Oxidative stress was evaluated by measuring the activity of liver enzymes associated with antioxidant system. The soybean protein was administrated in the diets at 20, 40, and 60% levels and its effects were evaluated compared with a fish meal diet. Growth and feed efficiency were affected negatively from 40% level. Increased RBA and expression levels of TGF‐β1 and β2m were found in HK only at 40% level. In intestine, at 60% level CSF‐1R expression was upregulated and some signs of inflammation were evident. In liver, at 60% level lipid accumulation in hepatocytes was observed and enzyme activity was increased. Dietary administration of soybean protein indicated changes from 40% in growth and immune response, and exerted an antioxidative effect at 60% level.     

CLINICAL VALUE OF FRUCTOSAMINE MEASUREMENTS AND FRUCTOSAMINE-ALBUMIN RATIO IN HYPOGLYCEMIC FERRETS (MUSTELA PUTORIUS FURO)

The objective of this preliminary study was to establish a reference range for plasma fructosamine concentration and fructosamine-albumin ratio in healthy ferrets and to compare these reference intervals to values obtained from hypoglycemic ferrets. Fructosamine concentration has been shown to reflect blood glucose concentration over the previous 1 to 2 weeks in other animal species, and may be a useful indicator of chronic hypoglycemia in ferrets diagnosed with insulinoma. Plasma fructosamine was measured with an automated colorimetric assay using nitroblue tetrazolium. Thirty-two clinically healthy and 5 hypoglycemic ferrets were included in the study. The reference interval in healthy ferrets for fructosamine was 110 (98 to 123) – 203 (191 to 218) μmol/L, and the reference interval for plasma fructosamine-albumin ratio was 5.1 (4.6 to 5.6) – 8.6 (8.2 to 9.0) μmol/g. Results for hypoglycemic ferrets were within the ranges for both fructosamine and fructosamine-albumin ratio. As there were no significant differences between the healthy and hypoglycemic ferrets, this study suggests that fructosamine concentration and fructosamine-albumin ratio are not likely to be useful in determining insulinoma-associated chronic hypoglycemia in ferrets.     

Soil fertility and GIS raster models for tropical agroforestry planning in economically depressed and contaminated Caribbean areas (coffee and kidney bean plantations)

In the jaragua-bahoruco-enriquillo biosphere reserve, located on the southern border between the Dominican Republic and Haiti, there are depressed rural areas with soils with high content in Cadmium and other heavy metals which originate naturally in the geological substrate. Data from 80 soils and an inventory of 76 plantations (coffee and kidney bean were used) to design a GIS (geographic information systems) tool which integrated statistical multivariate methods, soil parameters including heavy metal content into models of land planning, agricultural development, forests and protection of the health of the area’s inhabitants and the natural environment. This GIS tool is based on raster models of an open source, which use combination and reclassification operations based on the maps, geostatistical methods (Kriging), statistical analyses external to the GIS, and cartography of limiting and excluding particular factors for crops (including heavy metal soil content). The GIS tool developed discriminates extreme situations in sustainable agroforestry planning in contaminated rural areas of the Caribbean, Central America and other tropical regions.     

Epicormics in 13-year-old Quercus petraea: small effect of provenance and large influence of branches and growth unit limits

? The provenance effect on epicormics is poorly documented and restricted to epicormic shoots. Our objective was to characterize the relationship between epicormics and provenance on 13-year-old Quercus petraea trees, taking into account their growth traits.

? On the growth units (GU) studied, epicormics were essentially isolated buds (95%) and they were mainly located at branch bases, secondarily on GU limits and marginally on lateral position. Provenance effect was very small on the number of epicormics and slightly larger on the number of branches and GU limits. On the contrary, the growth situation-independently from provenance-proved to have a larger effect on the 2 latter growth traits.

? Altogether, these results clearly show the predominant effect of morphological traits and thus of ontogeny. This opens important research perspectives: how growth conditions and genetics (at progeny and individual levels) influence height growth, setting and fate of axillary buds on the one hand and fate of epicormic buds inserted directly on the stem, or at branch bases on the other hand.

     

Biological characteristics of the hydrological landscapes in the Bay of Biscay in spring 2009

In the present study we investigated the biogeography of macrozooplankton and fish biomass in the Bay of Biscay. In this region, we defined six different landscapes based on the hydrogeographical characteristics observed in spring 2009. We then related landscape's characteristics and environmental parameters such as light attenuation depth and chlorophyll‐a with macrozooplankton and fish acoustic biomass. Hydrodynamic structures together with coastal influences (river discharges, predation pressure and depth preference) and vertical thermohaline structure/mixing (feeding modes and ability to stay in preferred layers) appeared as the main factors determining the biological distribution. Besides, variance partitioning was used to assess the respective roles played by the hydrological environment, the geographical space and the biological environment alone, and their interactions. Results revealed that: (i) macrozooplankton and fish have a preference for different hydrogeographical landscapes; (ii) the association between hydrological conditions and geographical features, i.e. the spatial structure of the hydrological environment, plays a key role in the distribution of macrozooplankton; and (iii) prey–predator relationships have to be taken into account to provide a comprehensive characterization of habitat suitability.     

Responses of small rodents to habitat restoration and management for the imperiled Florida Scrub-Jay

Debate about the relative merits of single-species management versus more comprehensive approaches has intensified in recent years. In east-central Florida, USA, land managers use prescribed burns and mechanical cutting to manage and restore scrub habitat to benefit the imperiled Florida Scrub-Jay (Aphelocoma coerulescens). However, these land-management techniques may affect non-target taxa, especially the threatened southeastern beach mouse (Peromyscus polionotus niveiventris). We evaluated the collateral effects of single-species land management by trapping P. p. niveiventris and other small rodents in eighteen land-management compartments at Cape Canaveral Air Force Station, Florida during 2004–2005. Compartments were managed using either prescribed burns (N = 5), mechanical cutting (N = 6), checkerboarding (cut and uncut lanes alternating and overlapping, followed by a prescribed burn, N = 4) or left unburned and uncut for >50 year (N = 3). P. p. niveiventris was significantly more abundant in compartments managed with prescribed burns (mean ± SE: 4.2 ± 0.7 individuals/transect) than those managed with cutting alone (1.0 ± 0.3) or not managed for >50 y (0.2 ± 0.1 individuals/transect). In contrast, the cotton mouse (Peromyscus gossypinus) tended to be more abundant in compartments managed with mechanical cutting alone (2.6 ± 0.4 individuals/transect) compared to the other three management strategies (prescribed burns; 1.5 ± 0.4; checkerboarding, 1.1 ± 0.3; not managed, 1.6 ± 0.4 individuals/transect) but these differences were not statistically significant. Abundances of P. p. niveiventris and Florida Scrub-Jay breeding groups were positively correlated (r = 0.655), suggesting that both listed species benefit from similar management techniques. Thus, the mosaic of burned and cut patches used to improve habitat for the Florida Scrub-Jay also benefits an endemic, non-target species. Single-species management may benefit multiple species when restoration improves their shared habitat, which in this case is an endangered, fire-dependent ecosystem: Florida scrub.