Putting the pieces together: Recent growth,nutritional condition,and mortality of Engraulis anchoita larvae in the Southwest Atlantic

Dynamics of clupeiform fish populations such as anchovy are frequently impacted by environmental variations which can affect the success of the species recruitment. Herein, we have analyzed recent otolith growth rate, RNA/DNA nutritional condition index (sRD), and mortality rate of argentine anchovy larvae Engraulis anchoita from three different nursery areas in the Southwest Atlantic. We have evaluated the relationship between the environmental variables (abundance of copepod nauplii, temperature, chlorophyll‐a concentration, and abundance of E. anchoita larvae) and larval endogenous variables (size, weight, age, and otolith radius) to sRD and recent growth rate. Fast larval growth rates were observed toward the northern sector of the studied area, characterized by higher temperature. High values of sRD were associated with higher nauplii abundance in the proximity of coastal fronts. The larvae with the lowest growths and lowest minimum values of nutritional condition coincided with the area where there was less abundance of nauplii and higher larval mortality. Larval size and nauplii abundance were positive explanatory factors for both recent growth rate and sRD index. Temperature had a positive effect on recent growth rate and a negative effect on sRD index. This condition index was poorly explained in terms of model fit in comparison with the growth model. The results herein provided could be significant to better understand the recruitment of the species, as to determining favorable areas for the growth and survival of anchovy larvae.     

Injection molding of vertebral fixed cage implant

A vertebral cage is a hollow medical device which is used in spine surgery. By implanting the cage into the spine column, it is possible to restore disc and relieve pressure on the nerve roots. Most cages have been made of titanium alloys but they detract the biocompatibility. Currently PEEK (polyether ether ketone) is applied to various implants because it has good properties like heat resistance, chemical resistance, strength, and especially biocompatibility. A new shape of vertebral cage is designed and injection molding of PEEK is considered for production. Before injection molding of the cage, it is needed to evaluate process conditions and properties of the final product. Variables affecting the shrinkage of the cage are considered, e.g., injection time, packing pressure, mold temperature, and melt temperature. By using the numerical simulation program, MOLDFLOW, several cases are studied. Data files obtained by MOLDFLOW analysis are used for stress analysis with ABAQUS, and shrinkage and residual stress fields are predicted. With these results, optimum process conditions are determined.     

Microwave heat dyeing of polyester fabric

The effect of padding solution on the microwave heat dyeing of polyester fabric was studied extensively. Polyester fabrics were impregnated in aqueous urea solution and aqueous sodium chloride solution for 10 min and then dyed for 7 min by microwave apparatus (2 450 MHz, 700 W) under optimum conditions which provide good exhaustion. Aqueous solutions of urea and sodium chloride showed more effective than water as a padding solution for microwave heat dyeing. The type of solvent added in padding media and its concentration significantly affects the K/S values of dyed polyester fabric. Added solvents such as n-hexane, acetone, and dimethyl formamide were also more effective than 100% water as padding media for the microwave heat dyeing. It is supposed that the effect of used solvents on dyeing property of polyester fabrics depends on the solubility parameter difference between solvent and polyester fabric.     

Rapid identification of virulence genes in enterotoxigenic Escherichia coli isolates associated with diarrhoea in Queensland piggeries

OBJECTIVE: To identify virulence genes in enterotoxigenic E coli (ETEC) isolates associated with diarrhoea in neonatal, 1 to 3 week-old and weaned pigs in southeast Queensland. DESIGN: Multiplex PCR and serotyping were applied to E coli isolates obtained over a 5-year period (1998-2002) from cases diagnosed at Toowoomba Veterinary Laboratory. PROCEDURE: A total of 126 isolates from 25 different Queensland piggeries were tested for haemolytic activity on 5% sheep blood agar and by multiplex PCR for the presence of five commonly recognised fimbrial (F4, F5, F6, F41 and F18) and three enterotoxin genes (STa, STb, LT). A subset of 62 representative isolates were serotyped by slide agglutination. For comparative purposes, multiplex PCR was also performed on the DNA of 31 ETEC isolates from 9 serotypes originating from piggeries in southern New South Wales. RESULTS: A total of 113 (89.7%) of the isolates from Queensland possessed ETEC virulence genes, including 14 of 15 isolates from neonatal pigs (93.3%), 18 of 23 isolates from 1 to 3 week old pigs (78.3%) and 81 of 88 isolates from weaned pigs (92.1%). F4:STa:STb:LT (serotype O149) was the most prevalent pathotype in neonatal and 1-3 week old pigs and F4:STa:STb:LT (serotype O149) and F18:STa:STb:LT (serotype O141) were most prevalent in weaned pigs. In comparison, isolates obtained from neonatal pigs from New South Wales belonged to a more diverse range of pathotypes and serotypes. CONCLUSION: Multiplex PCR was a rapid and specific method for detecting the presence of ETEC virulence genes in porcine E coli isolates. For isolates obtained from cases of suspected colibacillosis in Queensland, growth of a heavy pure culture of haemolytic E coli was a sensitive prognostic indicator of the presence of ETEC virulence genes in the isolate. ETEC pathotypes and serotypes remained stable in Queensland piggeries over the five-year study period and appear to have changed little over the last three decades.     

An ecosystem-based assessment of the Korean blue crab trammel net fishery in the Yellow Sea and management implications

Landings in the blue crab, Portunus trituberculatus, fishery in Korean waters of the Yellow Sea have declined substantially from 11,000 t in the 1980s to 2,300 t in 2004. Blue crab habitat quality in the Yellow Sea has been degraded by anthropogenic activities including sand mining, land reclamation, and coastal pollution. Various traditional management measures have been implemented, including closed seasons during spawning and size limits, but these measures alone have been unsuccessful to conserve blue crab stocks. Consequently, a total allowable catch and a stock-rebuilding program using an ecosystem-based management approach were implemented in 2003 and 2006, respectively to rebuild blue crab stocks and restore habitats. This program involved assessment of both blue crab stock status and trammel-net fishery impacts at an ecosystem-level using an ecosystem-based fisheries assessment method ( [Zhang et al., 2009] and [Zhang et al., 2010]), which considered fishery data from catch and effort time-series, crab population biology, and ecosystem characteristics, including habitats and environmental conditions. Recent (2008) management status indices have shown significant positive change compared to conditions in 2000 with respect to sustainability of the stock and fishery and with regards to biodiversity and ecosystem habitat quality.     

Effect of dietary supplementation of inulin and W. cibaria on haemato‐immunological parameters of hybrid surubim (Pseudoplatystoma sp)

The dietary supplementation of prebiotics, probiotics and symbiotic in hybrid surubins (a Pseudoplatystoma corruscans and P. fasciatum cross) was evaluated for the effects on their autochthonous intestinal microbiota and on haematological and immunological parameters. A total of 160 fish were divided into four treatment groups with four replicates each. The treatment groups were fed with the following diets for 15 days: control diet without supplementation; 0.5% inulin (prebiotic) supplementation; Weissella cibaria (CPQBA 001‐10 DRM 02) (7.87 ± 0.2 log CFU g^?1) supplementation; or 0.5% inulin and W. cibaria supplementation (symbiotic group). The midgut intestines of the fish with the symbiotic diet supplementation had higher concentrations of lactic acid bacteria (7.07 ± 1.11 log CFU g^?1) and low levels of Vibrio spp (1.90 ± 0.60 log CFU g^?1) and Pseudomonas spp (2.23 ± 1.48 log CFU g^?1). In addition, increased erythrocytes and reduced circulating neutrophils were observed in this group. No differences in blood glucose, serum protein or lysozyme levels were detected between treatment groups. However, a higher concentration of total immunoglobulin was observed in fish fed with the probiotic and symbiotic diets. The addition of 0.5% inulin (prebiotic) thus W. cibaria (probiotic) to the diet of Pseudoplatystoma hybrid surubins reduce the number of pathogenic bacteria and stimulate the beneficial intestinal microbiota and may possibly alter their immune defence system.     

How much variation can be explained by seasonal,spatial and environmental effects in nekton assemblages of the Terminos Lagoon?

• 1. The coastline is very sensitive to both climatic and human influences but also provides essential goods and services upon which human welfare depends. Species inhabiting these coastal areas provide valuable resources and enhance ecosystem functioning: it is therefore essential to understand the main factors influencing species abundance patterns. The aim of this study is to estimate the amount of variation in nekton coastal assemblages explained by spatial, temporal and environmental variables.
• 2. Nekton sampling was carried out over 17 months in the Terminos Lagoon, a reserve area situated in the Gulf of Mexico, using a shrimp trawl. At each station, 11 environmental variables were recorded. The influence of seasonal, spatial and environmental variables on nekton species abundance was analysed using Partial Canonical Correspondence Analysis (PCCA).
• 3. The explanatory variables explained only 19.7% of the total observed variation in the nekton community for the Terminos Lagoon. The major part of the explained variation was due to the spatial effect (9.2%), while environmental variables and seasonality explained only 3.6% and 0.8%, respectively, suggesting the necessity to consider experimental fishing design in such artisanal fisheries.
• 4. Results also suggest focusing on more integrative indicators of community structure such as measures of taxonomic diversity based on presence/absence or on measures related to functional attributes of communities rather than using species abundance patterns to predict changes in coastal ecosystems.

Copyright © 2007 John Wiley & Sons, Ltd.     

Abnormal changes in both mandibular salivary glands in a dog: Non-mineral radiopaque sialoliths

A 10-year-old Maltese dog was presented with a firm mass on the left side of his neck. Physical examination confirmed a firm mass in the left and a submandibular swelling in the right cervical region. Sialolithiasis and associated sialocele in both mandibular salivary glands were suspected and bilateral sialoadenectomy was performed. The stones were identified as non-mineral sialoliths.