Physiological effects of natural olive oil antioxidants utilization in rainbow trout (<Emphasis Type="Italic">Onchorynchus mykiss</Emphasis>) feeding

Olive mill vegetation water (VW) is an olive oil by-product rich in polyphenols has powerful antioxidant effects. In light of the interest on the research of novel natural antioxidants to use in fish feed, the aim of this research was to use VW as a potential substitute for artificial antioxidants in rainbow trout diet as well as checking its effects on the blood chemistry and digestive organ physiology of the fish. The experimental plan was monofactorial, balanced (4 × 3) and the experimental factor considered was the fish diet. Diets were isoproteic (CP 40%) and isoenergetic (18 MJ kg⁻¹ DM) with two inclusion levels of VW (1 and 5%: VW1 and VW5) tested against a control diet. A feeding trial was performed on quadruplicate groups of 200 fish (mean body weight: 44.2 g) fed experimental diets for 94 days. At the end of the trial, the growth performance traits were determined and sampling of blood and different tissues (brain, ovary, stomach, liver, and intestine) were carried out for haematology, endocrinology, histology, and digestive enzyme analysis. The main results of the present experimentation are that VW inclusion in rainbow trout feed slightly affects the productive traits and blood chemistry, while the histological structure of digestive organs and digestive enzyme physiology were not affected.     

Searching for interacting QTL in related populations of an outbreeding species

Many important crop species are outbreeding. In outbreeding species the search for genes affecting traits is complicated by the fact that in a single cross up to four alleles may be present at each locus. This paper is concerned with the search for interacting quantitative trait loci (QTL) in populations which have been obtained by crossing a number of parents. It will be assumed that the parents are unrelated, but the methods can be extended easily to allow a pedigree structure. The approach has two goals: (1) finding QTL that are interacting with other loci and also loci which behave additively; (2) finding parents which segregate at two or more interacting QTL. Large populations obtained by crossing these parents can be used to study interactions in detail. QTL analysis is carried out by means of regression on predictions of QTL genotypes.     

Application of Solid Phase Micro‐Extraction (SPME) to the analysis of pesticide residues in vegetables

Solid Phase Micro‐Extraction (SPME) is a new analytical technique, based on capturing the analytes by adsorption onto an organic phase coating a glass fibre, and subsequent direct desorption into the injector of a gas chromatograph. This technique has been successfully applied in the analysis of organic contaminants in water, giving linear responses and, in some cases, high sensitivities. The present paper reports data about the application of SPME to the analysis of pesticide residues in a vegetable matrix, testing over nearly one hundred active compounds, with two types of adsorbent phase (polydimethylsiloxane and Carbowax/divinylbenzene). A vegetable matrix spiked with pesticides was analyzed by SPME and by a traditional multi‐residue method; recoveries were determined and compared for the two cases. The behaviour of the analytical response by SPME was studied in the range 0.01–1 mg kg⁻¹ by adding increasing amounts of given pesticide mixtures to the vegetable matrix. The procedure was further tested by analyzing real samples, and gave some difficulties in recovering the whole amount of some of the residues present (in comparison with the traditional method). The SPME method was then improved by pre‐extracting with acetone and sonicating before the extraction/adsorption step. The results obtained were satisfactory (some certified matrices were also tested) with good accordance between the two methods. Nevertheless some active compounds showed very low responses or remained undetectable by SPME in our experimental conditions. © 2000 Society of Chemical Industry     

Bad for the environment, good for the farmer? Urban sanitation and nutrient flows

Due to poor urban sanitation farmers in and around most cities in developing countries face highly polluted surface water. While the sanitation challenge has obvious implications for environmental pollution and food safety it can also provide ‘free’ nutrients for irrigating farmers. To understand the related dimensions, a box-flow model was used to identify the most important water and nutrient flows for the Ghanaian city of Kumasi, a rapidly growing African city with significant irrigation in its direct vicinity. The analysis focused on nitrogen and phosphorus and was supplemented by a farm based nutrient balance assessment. Results show that the city constitutes a vast nutrient sink that releases considerable nutrients loads in its passing streams, contributing to the eutrophication of downstream waters. However, farmers have for various practical reasons little means and motivation in using this resource of nutrients. This might change under increasing fertilizer prices as the nutrient load will continue to increase by 40% till 2015 assuming a widening gap between population growth and investments in water supply on one side and investments in sanitation on the other. However, even a strong investment into flushing toilets would not reduce environmental pollution due to the dominance of on-site sanitation systems, but instead strongly increase water competition. Key options to reduce the nutrient load would be via optimized waste collection and investment in dry or low-flush toilets. The latter seems also appropriate for the city to meet the water and sanitation Millennium Development Goals (MDGs) without increasing water shortages in toilet connected households.     

Bayesian estimation of diagnostic sensitivity and specificity of a qPCR and a bacteriological culture method for Piscirickettsia salmonis in farmed Atlantic salmon (Salmo salar L.) in Chile

Early detection of piscirickettsiosis is an important purpose of government- and industry-based surveillance for the disease in Atlantic salmon farms in Chile. Real-time qPCRs are currently used for surveillance because bacterial isolation is inadequately sensitive or rapid enough for routine use. Since no perfect tests exist, we used Bayesian latent class models to estimate diagnostic sensitivity (DSe) and specificity (DSp) of qPCR and culture using separate two-test, single-population models for three farms (n = 148, 151, 44). Informative priors were used for DSp (culture (beta(999,1); qPCR (beta(98,2)), and flat priors (beta 1,1) for DSe and prevalence. Models were run for liver and kidney tissues combined and separately, based on the presence of selected gross-pathological signs. Across all models, qPCR DSe was 5- to 30-fold greater than for culture. Combined-tissue qPCR median DSe was highest in Farm 3 (sampled during P. salmonis outbreak (DSe = 97.6%)) versus Farm 1 (DSe = 85.6%) or Farm 2 (DSe = 83.5%), both sampled before clinical disease. Median DSe of qPCR was similar for liver and kidney, but higher when gross-pathological signs were evident at necropsy. High DSe and DSp and rapid turnaround-time indicate that the qPCR is fit for surveillance programmes and diagnosis during an outbreak. Targeted testing of salmon with gross-pathological signs can enhance DSe.     

Comparative growth of Pacific oyster (Crassostrea gigas) postlarvae with microfeed and microalgal diets

Two trials were carried out in the laboratory in order to assess the effect of microparticulated feed (F) and live (Thalassiosira pseudonana, M) diets on the growth of recently set (396 ± 13 μm shell height) and 2 mm Crassostrea gigas postlarvae. Different proportions of M and F (100:0, 75:25, 50:50; 25:75, 0:100) were delivered in a single dose of 3 h d⁻¹ in trial 1. Dietary M:F proportions of 100:0, 50:50, and 0:100 were delivered as a single pulse of 8 h d⁻¹ (P1) or two pulses of 4 h⁻¹ (P2) in trial 2. Maximal daily M ration was 296 cells μl⁻¹ d⁻¹ (trial 1), 150 M cells μl⁻¹ d⁻¹ (trial 2), or their equivalent F dry weight. Shell height (SH), dry (DW), and organic weight (AFDW) were evaluated weekly. Oysters from trial 1 significantly increased their size after 28 days, and exhibited no significant dietary differences in terms of DW (1.21 ± 0.15 to 2.01 ± 0.28 mg) or AFDW (0.091 ± 0.022 to 0.166 ± 0.029 mg). Newly set postlarvae (trial 2) also exhibited significant growth after 25 days. No dietary differences were observed in trial 2, yet P2 oysters attained significantly higher shell heights (825–912 μm) than P1 oysters (730–766 μm) after 25 d. Pulse effects were marginally not significant in terms of AFDW and growth rate. Together, these findings showed that balanced microfeeds have a practical potential for the culture of early C. gigas postlarvae, when they are delivered in pulse-feeding schemes     

Marine Demospongiae: A Challenging Treasure of Bioactive Compounds

In the last decades, it has been demonstrated that marine organisms are a substantial source of bioactive compounds with possible biotechnological applications. Marine sponges, in particular those belonging to the class of Demospongiae, have been considered among the most interesting invertebrates for their biotechnological potential. In this review, particular attention is devoted to natural compounds/extracts isolated from Demospongiae and their associated microorganisms with important biological activities for pharmacological applications such as antiviral, anticancer, antifouling, antimicrobial, antiplasmodial, antifungal and antioxidant. The data here presented show that this class of sponges is an exciting source of compounds, which are worth developing into new drugs, such as avarol, a hydroquinone isolated from the marine sponge Disidea avara, which is used as an antitumor, antimicrobial and antiviral drug.     

Integrated approach of multiple environmental datasets for the assessment of sediment contamination in marine areas affected by long-lasting industrial activity: the case study of Bagnoli (southern Italy)

Purpose

The Bagnoli’s brownfield site (southern Italy) is an environmental priority for the Italian Government and is currently considered as a case study for the definition and application of innovative approaches to ecosystem recovery after a prolonged pollution history and eventual steel plant decommissioning.

Materials and methods

Here, we analyse high-quality datasets that constrain the distribution patterns and sources of contaminants in the coastal zone facing the site where the steel plant operated for almost one century. Innovative statistical approaches provide new insights into the temporal and spatial distribution of anthropogenic impacts, documented over the last 30 years, following lines of evidence emerging from investigations on grain size, TOC, heavy metals, PAHs, PCBs and high-resolution morpho-bathymetric information.

Results and discussion

The results derived from statistical analysis, referred also to the seafloor morphological variability, highlighted the presence of recent disposal of highly contaminated sediments and their potential pathways of dispersion to wider and deeper water zones.

Conclusions

The adopted multidisciplinary approach yields fundamental information towards an effective and proper ecosystem recovery of highly contaminated marine coastal areas and provides at the same time, a sound base for the refitting of decommissioned industrial plants.

     

Effects of Negative Pressure Wound Therapy on Healing of Open Wounds in Dogs

Objective: To compare the effect of negative pressure wound therapy (NPWT) with standard‐of‐care management on healing of acute open wounds in dogs. Study Design: Prospective, controlled, experimental study. Animals: Adult dogs (n=10). Methods: Full‐thickness 4 cm × 2 cm wounds were surgically created on each antebrachium and in each dog were randomized to receive either NPWT or standard wound dressings (CON) for 21 days. Dressing changes and wound evaluations were made at 8 time points. First appearance of granulation tissue, smoothness of granulation tissue, exuberance, percent epithelialization, and percent contraction were compared. Biopsies for histopathology were taken, and histologic scores determined, at 5 time points, and aerobic bacterial wound cultures performed at 2 time points. Results: Granulation tissue appeared significantly earlier, and was smoother and less exuberant in NPWT wounds compared with CON wounds. Percent contraction in NPWT wounds was less than CON wounds after Day 7. Percent epithelialization in NPWT wounds was less than CON wounds on Days 11, 16, 18, and 21. Histologic scores for acute inflammation were higher in NPWT on Day 3, and lower on Day 7, than CON wounds. Bacterial load was higher in NPWT on Day 7. Conclusion: NPWT accelerated appearance of smooth, nonexuberant granulation tissue; however, prolonged use of NPWT impaired wound contraction and epithelialization.