Soy protein concentrate as a substitute for fish meal in diets for juvenile Acanthopagrus schlegelii: effects on growth,phosphorus discharge and digestive enzyme activity

The current high demand and cost of fish meal (FM) necessities the evaluation of alternative plant protein ingredients in diets of farmed marine fish. A 56‐day feeding trial was performed to study the effects of replacement of FM with soy protein concentrate (SPC) in diets of Acanthopagrus schlegelii. Diets were prepared at levels of 0%, 30%, 47.5%, 65%, 82.5% and 100% SPC, respectively, replacing FM. The results indicated no significant differences (p > .05) in % weight gain (WG) and specific growth rate of fish fed S30% to S82.5% diets compared with the control diet while, further inclusion at 100% significantly depressed growth performance. SPC inclusion and phytase supplementation significantly affected the phosphorous discharge (P‐load) showing lowest value (3.83 ± 0.53 g/kg WG) in S100% compared to control (14.79 ± 0.37 g/kg WG) and in fish fed S30% diet (13.24 ± 0.89 g/kg WG) (p < .05). The results of this study showed that FM could be substituted up to 82.5% by SPC in the diet of Acanthopagrus schlegelii fingerlings (5.53 ± 0.12 g) without any adverse effects. Phytase supplementation SPC based diets could be effective in reducing the phosphorus load in the aquatic culture environment.     

Distribution and habitat characteristics of three sympatric cetacean species in the coastal waters of Matang,Perak, Peninsular Malaysia

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Dietary habits of grazers influence their suitability as biological controls of fouling macroalgae in ex situ mariculture

The dietary habits of the sea urchin Salmacis sphaeroides and the gastropod Trochus maculatus in ex situ mariculture were examined. Fouling algal assemblages on terracotta tiles were exposed to the grazers and compared. Except for Day 0, the assemblages on Days 2, 13 and 27 differed significantly across treatments. S. sphaeroides rapidly consumed most algae, leaving an assemblage dominated by turf algae and bare tile. T. maculatus primarily fed on green filamentous algae, resulting in an even distribution of other algal functional groups, while control tiles were dominated by green filamentous algae. Using three representative fouling algae species (Bryopsis corymbosa, Hypnea spinella and Lobophora variegata), the consumption rates of both grazers and dietary preferences of S. sphaeroides were examined through a single‐diet and a choice experiment respectively. The single‐diet experiment revealed differential algal consumption rates for S. sphaeroides (H. spinella = B. corymbosa > L. variegata) and T. maculatus (B. corymbosa > H. spinella = L. variegata). The choice experiment showed that S. sphaeroides preferred H. spinella over the other two species. These experiments highlighted the importance of understanding the dietary habits of grazers as this has direct implications on their effectiveness as biological controls of fouling macroalgae in mariculture.     

Physicochemical characteristics of onion (Allium cepa L.) tissues

The structure and mechanical properties of onions are important factors affecting their textural quality. The onion bulb consists of several layers of pigmented, papery scales surrounding fleshy storage scales that comprise an upper epidermis, an intermediate parenchyma tissue, and a lower epidermis. The purpose of this study was to examine the chemical composition of cell walls from the papery scales and outer fleshy scales of onion (Allium cepa L. cv. Sturon) in relation to their mechanical properties. Cell-wall material (CWM) was prepared from the component tissues and analyzed for its carbohydrate and phenolic composition. The CWMs were rich in uronic acid and glucose, with smaller quantities of arabinose, galactose, and xylose. In the fleshy scales, the lower epidermis contained relatively more galactose-rich pectic polysaccharides, whereas the upper epidermis and the papery scales contained virtually no galactose. Analysis of mechanical properties showed that the order of strength of the tissues was papery scales > fleshy scales, which were in the order lower epidermis > upper epidermis > intermediate parenchyma. The upper epidermis of fleshy scales was stronger in the vertical than the horizontal direction, and both orientations showed negligible notch sensitivity. Cyclohexane-trans-1,2-diaminetetraacetate-induced vortex-induced cell separation of the intermediate layer of fleshy scales indicated that calcium cross-linking may play an important role in cell-cell adhesion. A small but significant amount of ferulic acid was found in the walls, predominantly in the thick cuticle of the lower epidermis of fleshy scales. Alkali-labile wall-bound flavonoids were also detected.     

Thermal effects on water retention behaviour of unsaturated collapsible loess

Journal of Soils and Sediments - Temperature has a significant influence on water retention curve (WRC) because temperature affects surface tension of water and volumetric behaviour of soil....     

Molecular mimicry regulates ABA signaling by SnRK2 kinases and PP2C phosphatases

Abscisic acid (ABA) is an essential hormone for plants to survive environmental stresses. At the center of the ABA signaling network is a subfamily of type 2C protein phosphatases (PP2Cs), which form exclusive interactions with ABA receptors and subfamily 2 Snfl-related kinase (SnRK2s). Here, we report a SnRK2-PP2C complex structure, which reveals marked similarity in PP2C recognition by SnRK2 and ABA receptors. In the complex, the kinase activation loop docks into the active site of PP2C, while the conserved ABA-sensing tryptophan of PP2C inserts into the kinase catalytic cleft, thus mimicking receptor-PP2C interactions. These structural results provide a simple mechanism that directly couples ABA binding to SnRK2 kinase activation and highlight a new paradigm of kinase-phosphatase regulation through mutual packing of their catalytic sites.     

Colloid oncotic pressure and total protein changes in horses during anesthesia fluid therapy

It is unknown whether overlapping or sequential use of nonsteroidal anti‐inflammatory (NSAIDs) results in an increased risk for gastrointestinal (GI) ulceration. The purpose of this pilot study was to evaluate the GI effects of various combinations of an injectable NSAID followed by an oral NSAID, a scenario often employed clinically for management of the pre‐ and post‐operative canine patient. Six healthy Walker hounds received four treatment regimens in a randomized, cross‐over design with a 2 week washout period between each treatment week: carprofen (4 mg kg^–1, SQ) followed by placebo (PO, q24 × 4 days); placebo (SQ) followed by deracoxib (3–4 mg kg^–1, PO, q24 × 4 days); carprofen (4 mg kg^–1, SQ) followed by carprofen (4 mg kg^–1, PO, q24 × 4 days); carprofen (4 mg kg^–1, SQ) followed by deracoxib (3–4 mg kg^–1, PO, q24 ×4 days). Weekly bloodwork (CBC, biochemistry panel, fecal evaluation, fecal occult blood) and daily clinical scoring (TPR, vomiting, diarrhea, appetite) were obtained. GI endoscopy was performed on days –2, 1, 2, 5, and 11 days post treatment of each treatment period and lesions scored using a previously reported 6‐point scale. Data was analyzed using a mixed anova for repeated measures. There were no significant differences in clinical or clinicopathologic data between groups. Within the carprofen‐carprofen and carprofen‐deracoxib groups, lesions worsened by Day 5 (1 day after last oral dose) for the fundic and antral regions (p < 0.05). Fundic, antral and lesser curvature lesions improved by Day 5 in the carprofen‐placebo group and lesser curvature lesions improved in the placebo‐deracoxib group (p < 0.05). No significant within‐group differences were noted for the esophagus, cardia or duodenum. The small number of dogs precludes general conclusions about the safety of sequential NSAID use, but these results suggest that a larger scale study is warranted.