Direct measurement of rice bran lipase activity for inactivation kinetics and storage stability prediction

Rice bran is a rich source of valuable nutrients and has potential for high-value applications. Endogenous lipases catalyze the hydrolysis of rice bran oil to free fatty acids, which initiates lipid oxidation. The evaluation of the success of rice bran stabilization processes in terms of the degree of lipid oxidation and shelf-life has so far relied on the measurement of free fatty acid content over a storage period of 3–6 months. In the present study, a photometric and a titrimetric pH-stat method for direct lipase activity measurement immediately after debranning were adapted to rice bran. The photometric method was further applied to determine rice bran lipase/esterase inactivation kinetics, which are useful to optimize stabilization treatments in order to prevent overprocessing and retain maximum level of nutrients. Rice bran was heat-treated in a specialized, hermetically sealable reactor at controlled holding times (5–40 min), temperatures (70–145 °C) and moisture contents (10–20%). Temperature dependency of the lipase/esterase inactivation rate could be described by the Arrhenius equation. Empirical findings on the importance of moisture content for effective rice bran stabilization could be quantified. Furthermore, the results demonstrate the great potential of the method to predict the shelf-life of stabilized rice bran without time-consuming storage tests.     

Inflammatory pseudotumours of the urinary bladder in dogs resembling human myofibroblastic tumours: a report of eight cases and comparative pathology

Eight cases of inflammatory myofibroblastic tumours (IMT) of the urinary bladder in dogs are described, including their clinical, imaging, morphological, and histopathological aspects. Old small breed female dogs were more commonly affected. Haematuria was the main clinical sign, often associated with dysuria and crystalluria. The IMT appeared as single or multiple, polypoid, firm masses, measuring 1-7 cm. Histologically, the masses were well delineated, covered by a benign hyperplastic urothelium and diffusely infiltrated by a mixed inflammatory component. The cells were spindle-shaped, adopting a fascicular, pallisading or whirling organisation and were vimentin and variably desmin and actin positive. The nuclei were globular, containing open chromatin and prominent nucleoli. Mild to moderate pleomorphism and little mitotic activity were present. These morphological features are compatible with human myofibroblastic inflammatory tumours.     

Fishing groupers towards extinction: a global assessment of threats and extinction risks in a billion dollar fishery

Groupers are a valuable fishery resource of reef ecosystems and are among those species most vulnerable to fishing pressure because of life history characteristics including longevity, late sexual maturation and aggregation spawning. Despite their economic importance, few grouper fisheries are regularly monitored or managed at the species level, and many are reported to be undergoing declines. To identify major threats to groupers, the International Union for Conservation of Nature (IUCN) Red List criteria were applied to all 163 species. Red List assessments show that 20 species (12%) risk extinction if current trends continue, and an additional 22 species (13%) are considered to be Near Threatened. The Caribbean Sea, coastal Brazil and Southeast Asia contain a disproportionate number of Threatened species, while numerous poorly documented and Near Threatened species occur in many regions. In all, 30% of all species are considered to be Data Deficient. Given that the major threat is overfishing, accompanied by a general absence and/or poor application of fishery management, the prognosis for restoration and successful conservation of Threatened species is poor. We believe that few refuges remain for recovery and that key biological processes (e.g. spawning aggregations) continue to be compromised by uncontrolled fishing. Mariculture, through hatchery‐rearing, increases production of a few species and contributes to satisfying high market demand, but many such operations depend heavily on wild‐caught juveniles with resultant growth and recruitment overfishing. Better management of fishing and other conservation efforts are urgently needed, and we provide examples of possible actions and constraints.     

A rapid high-precision flow cytometry based technique for total white blood cell counting in chickens

The automated analysis of total white blood cell count and white blood cell differentials is routine in research and clinical diagnosis in mammalian species. In contrast, in avian haematology these parameters are still estimated by conventional microscopic procedures due to technical difficulties associated with the morphological peculiarities of avian erythrocytes and thrombocytes. Both cell types are nucleated and fairly resistant to cell lysis, a prerequisite for automated leukocyte quantification and differentiation by commercial instruments. By using an anti-CD45 monoclonal antibody in combination with selected subset specific markers we have established a simple (no-lyse no-wash single-step one-tube) flow cytometry based technique for high precision chicken blood cell quantification. EDTA-blood samples are diluted, spiked with fluorescence beads and incubated with a mixture of fluorochrome conjugated chicken leukocyte specific antibodies. We demonstrate that total leukocyte numbers as well as thrombocyte, monocyte, T-cell, B-cell and heterophilic granulocyte numbers can be determined by flow cytometry in a single step without prior cell lysis, cell separation or cell washing steps. Importantly, we also show that blood samples can be fixed prior to cell staining which enables shipping of samples making the technology widely available. Comparison of this technique with conventional microscopy revealed superior precision. By comparing leukocyte differentials of two chicken populations and during immune system development after hatch we demonstrate that large sample numbers can be analysed within hours. This technique will help to overcome previous restrictions in immune status analysis in chickens in experimental systems, during vaccine testing and health status monitoring in chicken flocks. Advances in avian genomics should facilitate the development of appropriate tools for other avian species in the future which will make this technique broadly applicable.     

Recovery of alpine tundra under protection after damage by human activities in the rocky mountains of Colorado

Visitors to Rocky Mountain National Park are especially attracted to its easily accessible alpine tundra, which widely dominates the landscape above tree-limit. A remarkable summer highway, Trail Ridge Road, traverses more than twelve miles (19 km ) of tundra, rising in its highest tract to elevations of over 12,000 feet (3,658 m). Visitor activities are largely confined to the immediate vicinity of ‘black-top’ parking areas located at points of special interest, but many persons do venture out along the established pathways. Only a few visitors each year are venturesome enough, or take the time, to wander at leisure over the gently rolling land. Trampling by the visitors kills plants and initiates erosion processes which eventually remove all plants and the finer organic and mineral soil particles. The present study was undertaken to get information on the processes and rates involved in the recovery of the tundra when protected from further visitor effects by channelling their movement along paths, and by erecting exclosures. Observations made over a 4-year period showed almost complete recovery of vegetation which had been trampled for only one year. In an area which had been trampled for 26 years, there was an increase in vegetative growth, but the potentially dominant species, Kobresia myosuroides, still had reduced vigour, and some of the other important species in the natural association were still absent. One are that had been severely damaged during 38 years of trampling showed no improvement after four years of protection. The time-factor in tundra recovery is quite shocking. We estimate that some tundra that has been damaged by only a few seasons of human activity will require hundreds of years, possibly even a thousand, to rebuild a natural and persistent (climax) ecosystem.     

Amino acid digestibility of animal protein ingredients for bullfrogs in different phases of post‐metamorphic development

The development of diets that economically and ecologically meet the requirements of bullfrogs (Lithobates catesbeianus) is important for frog farming. Therefore, the objective of this study was to determine the apparent digestibility coefficients for essential amino acids of eight animal feed ingredients (poultry byproduct meal, meat and bone meal, salmon byproduct meal, tilapia byproduct meal, spray‐dried blood meal, powered red blood cells, feather meal and sardine meal) used in the diets of bullfrogs. Additionally, the limiting digestible amino acids were determined for each ingredient. Bullfrogs in different phases of post‐metamorphic development were used: 810 animals in the early phase (mean weight: 40 ± 10 g), 405 animals in the growing phase (95 ± 15 g) and 243 animals in the finishing phase (175 ± 25 g). Poultry byproduct meal, salmon byproduct meal and blood meal exhibited the largest number of high apparent digestibility coefficients for essential amino acids (>70%) in the early, growing and finishing phases, respectively. The animal protein ingredients were well digested by the bullfrogs and could be used in practical diets for this species, respecting the limits of inclusion and digestibility values for each developmental phase.     

Postprandial kinetics of gene expression of proteins involved in the digestive process in rainbow trout (<Emphasis Type="Italic">O. mykiss</Emphasis>) and impact of diet composition

The impact of increased incorporation of plant ingredients on diets for rainbow trout was evaluated in terms of gene expression of gastric (gastric lipase, pepsinogen) and intestinal (prolidase, maltase, phospholipase A2) digestive enzymes and nutrient transporters (peptide and glucose transporters), as well as of postprandial levels of plasma glucose, triglycerides and total free amino acids. For that purpose, trout alevins were fed from the start of exogenous feeding one of three different experimental diets: a diet rich in fish meal and fish oil (FM–FO), a plant-based diet (noFM–noFO) totally free from fish meal and fish oil, but containing plant ingredients and a Mixed diet (Mixed) intermediate between the FM–FO and noFM–noFO diets. After 16 months of rearing, all fish were left unfed for 72 h and then given a single meal to satiation. Blood, stomach and anterior intestine were sampled before the meal and at 2, 6 and 12 h after this meal. The postprandial kinetics of gene expression of gastric and intestinal digestive enzymes and nutrient transporters were then followed in trout fed the FM–FO diet. The postprandial profiles showed that the expression of almost all genes studied was stimulated by the presence of nutrients in the digestive tract of trout, but the timing (appearance of peaks) varied between genes. Based on these data, we have focused on the molecular response to dietary factors in the stomach and the intestine at 6 and 12 h after feeding, respectively. The reduction in FM and FO levels of dietary incorporation induced a significant decrease in the gene expression of gastric lipase, GLUT2 and PEPT1. The plasma glucose and triglycerides levels were also reduced in trout fed the noFM–noFO diet. Consequently, the present study suggests a decrease in digestive capacities in trout fed a diet rich in plant ingredients.     

Integrating fine‐scale seafloor mapping and spatial pattern metrics into marine conservation prioritization

1. Marine protected area (MPA) planning often relies on scientific principles that help ensure that an area selected for conservation will effectively protect biodiversity. Capturing ecological processes in MPA network planning has received increased attention in recent years. High‐resolution seafloor maps, which show patterns in seafloor bio‐physical characteristics, can support our understanding of ecological processes.
2. In part, owing to a global lack of high‐resolution seafloor maps, studies that aim to integrate seascape spatial pattern and conservation prioritization often focus on shallow biogenic habitats with less attention paid to deeper benthic seascapes (benthoscapes) mapped using acoustic techniques. Acoustic seafloor mapping strategies yield the spatial information required to extend conservation prioritization research into these environments, making incorporating seafloor ecological processes into conservation prioritization increasingly achievable.
3. Here, a new method is proposed and tested that combines benthoscape mapping, landscape ecology metrics and a conservation decision support tool to prioritize areas with structural and potential connectivity value in MPA placement. Using a case study in eastern Canada, benthoscape composition and configuration were quantified using spatial pattern metrics and integrated into Marxan.
4. Results illustrate how large patches of seafloor habitat in close proximity to neighbouring patches can be preferentially selected when benthoscape configuration is considered. The flexibility of the method for including relevant spatial pattern metrics or species‐specific movement data is discussed to illustrate how benthic habitat maps can improve existing conservation planning methods and complement existing and future work to support marine biodiversity conservation.

     

Arbuscular mycorrhizal fungi of a Mediterranean island (Pianosa), within a UNESCO Biosphere Reserve

In this work we have determined the community composition of spore-forming arbuscular mycorrhizal fungi (AMF) in a maquis site on Pianosa island, a protected area within the Tuscan Islands UNESCO Biosphere Reserve, Italy. We have analysed rhizosphere soil of the dominant plant species Pistacia lentiscus, Smilax aspera, Rosmarinus officinalis and of the endemic plant Helichrysum litoreum. The AMF species recovered were: Scutellospora dipurpurescens, Glomus coronatum, Glomus mosseae, Glomus etunicatum, Glomus geosporum, Glomus viscosum, Entrophospora sp., Pacispora sp. and Glomus rubiforme. The identification of native S. dipurpurescens and G. coronatum was carried out on spores isolated from rhizosphere soil of H. litoreum, by combining morphological traits and 18S (SSU) and ITS rDNA sequences. Therefore, AMF species of Pianosa rhizosphere soils represent an important repository for the conservation and maintenance in their natural habitat of such beneficial symbionts, key microorganisms of soil fertility.