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Sofia Morais Luis Narciso Elsa Dores Pedro Pousaro-Ferreira 《Journal of the World Aquaculture Society》2005,36(3):302-310
Abstract— Most marine fish larviculture is dependent on the culture and nutritional manipulation of live prey, of which the rotifers Brachionus sp. are one of the most commonly used. The particular reproductive characteristics of gilthead seabream Spus aurata L. lead to an egg overproduction in commercial hatcheries, where the excess is normally wasted. This study was developed with the objective of testing seabream eggs as an enrichment product for Brachionus sp., using as control the commercial product Algamac 2000×. In view of the need to preserve and store the eggs produced in excess, freezedrying was examined as a possible technical solution for this purpose. The fatty acid profiles of the tested enrichment products (fresh seabream eggs, freeze-dried eggs and Algamac 2000×), as well as of the enriched rotifers at 0 h and after 3,6,12, 15, 18 and 24 h of enrichment, were analyzed. Freeze-dried eggs were stored for 14 and 58 wk prior to analysis, in order to examine a potential deterioration of the fatty acid nutritional quality. A potential use of seabream eggs as an enrichment product for Brachionus sp. was demonstrated. Rotifers enriched with eggs, fresh and freeze-dried, presented relatively high levels of polyunsaturated fatty acids (PUFA), highly unsaturated fatty acids (HUFA; × C20 and 2 double bonds), and fatty acid methyl esters (FAME), a docosahexaenoic acid (DHA)/eicosapentaenoic acid (EPA) ratio of about 2 and a fairly high (n-3)/(n-6) ratio, especially during the first 3-6 h of enrichment. When freeze-dried eggs were stored in a dry atmosphere during 14 and 58 wk, only a slight and nonsignificant decrease was noted in the fatty acid content over this period of time. Therefore, freeze-drying may be an effective way of preserving the eggs in excess, at least up to 58 wk of storage. 相似文献
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Grougnet R Magiatis P Mitaku S Terzis A Tillequin F Skaltsounis AL 《Journal of agricultural and food chemistry》2006,54(20):7570-7574
A procedure, based on XAD-4 adsorption resin, which permits the obtainment of enriched polyphenolic extracts from Sesamum indicum perisperm (coat) has been developed. Chemical analysis of the obtained extracts led to the identification of 16 lignans. Among them, two new lignans, (+)-saminol and (+)-episesaminone-9-O-beta-D-sophoroside, have been isolated. Additionally, the relative stereochemistry of (-)-sesamolactol, previously reported as todolactol A epimer, has been unequivocally defined using X-ray crystallography. The structures of all new compounds were determined by spectroscopic methods, mainly by the concerted application of 1D and 2D NMR techniques (HMQC, HMBC, and NOESY) and mass spectroscopy. 相似文献
25.
Vranakis I Kokkini S Chochlakis D Sandalakis V Pasparaki E Minadakis G Gikas A Tselentis Y Psaroulaki A 《Comparative immunology, microbiology and infectious diseases》2012,35(2):123-127
Coxiella burnetii, the causative agent of Q fever, is an obligatory intracellular bacterium with worldwide distribution. The aim of this study was to determine the prevalence of C. burnetii phase II antibodies in two different groups (high and low risk) of healthy human population and investigate the epidemiological characteristics of the infection in the island of Crete (southern Greece). Collection and testing by IFA of 493 sample sera for IgG and IgM antibodies against C. bumetii phase II antigen indicated a prevalence of IgG antibodies of 48.7%. Of the seropositive individuals, 34% also revealed IgM seropositive antibody titers. Analysis of 225 sample sera by IFA from high risk population presented a prevalence for C. burnetii of 62.2%. Our findings revealed that C. burnetii is highly endemic in Crete, indicating a high exposure of the population to the pathogen regardless of occupation or place of residence. 相似文献
26.
Ljusk Ola Eriksson Sofia Backéus Frederick Garcia 《European Journal of Forest Research》2012,131(4):1199-1209
Climate change is expected to have substantial effects on many aspects of forest ecosystems, including timber production. Temperatures in northern Europe are expected to increase considerably, although there is substantial uncertainty about both the seasonal and average changes that will occur. In Scandinavia, production is predicted to increase across most of the area covered by boreal forest, since the growth of trees in the region is currently limited by temperature. Therefore, we have analyzed the importance of adapting management practices to future climate changes and considered possible ways to address associated stand management problems. For this purpose, we simulated climate scenarios with temperature increases ranging from 2.5 to 6.0°C over a 100-year period, and effects on typical Swedish stands with several species, then optimized their management with simulated annealing. The results indicate that the maximum considered temperature trend would raise the economic value of the stands by almost 5% more than the minimum trend. However, the importance of optimizing management plans in accordance with the correct temperature scenario appears to be limited. The plan optimized for the minimum temperature trend was only marginally inferior to the plan optimized for the maximum temperature trend in the maximum trend scenario, and vice versa. It also seemed adequate to use a deterministic formulation of the problem, and in cases where a stochastic climate change model generated more robust plans, the advantage could be attributed to model artifacts rather than climate change per se. 相似文献
27.
María Ortuo Maria S. Latrofa María A. Iborra Pedro Prez‐Cutillas Luis J. Bernal Jos Risueo Clara Muoz Ana Bernal Pedro F. Snchez‐Lopez Manuel Segovia Giada Annoscia Carla Maia Sofia Cortes Lenea Campino Domenico Otranto Eduardo Berriatua 《Zoonoses and public health》2019,66(8):961-973
Leishmania infantum causes human and canine leishmaniosis. The parasite, transmitted by phlebotomine sand flies, infects species other than dogs and people, including wildlife, although their role as reservoirs of infection remains unknown for most species. Molecular typing of parasites to investigate genetic variability and evolutionary proximity can help understand transmission cycles and designing control strategies. We investigated Leishmania DNA variability in kinetoplast (kDNA) and internal transcribed spacer 2 (ITS2) sequences in asymptomatically infected wildlife (n = 58) and symptomatically and asymptomatically infected humans (n = 38) and dogs (n = 15) from south‐east Spain, using single nucleotide polymorphisms (SNPs) and in silico restriction fragment length polymorphism (RFLP) analyses. All ITS2 sequences (n = 76) displayed a 99%–100% nucleotide identity with a L. infantum reference sequence, except one with a 98% identity to a reference Leishmania panamensis sequence, from an Ecuadorian patient. No heterogeneity was recorded in the 73 L. infantum ITS2 sequences except for one SNP in a human parasite sequence. In contrast, kDNA analysis of 44 L. infantum sequences revealed 11 SNP genotypes (nucleotide variability up to 4.3%) and four RFLP genotypes including B, F and newly described S and T genotypes. Genotype frequency was significantly greater in symptomatic compared to asymptomatic individuals. Both methods similarly grouped parasites as predominantly or exclusively found in humans, in dogs, in wildlife or in all three of them. Accordingly, the phylogenetic analysis of kDNA sequences revealed three main clusters, two as a paraphyletic human parasites clade and a third including dogs, people and wildlife parasites. Results suggest that Leishmania infantum genetics is complex even in small geographical areas and that, probably, several independent transmission cycles take place simultaneously including some connecting animals and humans. Investigating these transmission networks may be useful in understanding the transmission dynamics, infection risk and therefore in planning L. infantum control strategies. 相似文献
28.
Rafael Guerra Ricardo Cabeças Jesus Diaz Tim Knott Inês Freitas Hugo Vilhena Sofia Duarte 《Topics in companion animal medicine》2018,33(4):109-113
Cataracts are among the most common ocular diseases, and are a leading cause of vision loss in humans and dogs. Jack Russell Terriers (JRT) and Labrador Retrievers (LR) are among the most popular canine breeds in the United Kingdom, and also among the most affected by cataracts.This study aimed to analyze the clinical features and the surgical outcome of cataracts in JRT and LR in an ophthalmologic reference Veterinary Hospital in the United Kingdom. For that purpose, medical records from JRT and LR diagnosed with cataracts between January 2015 and December 2016 were retrospectively evaluated. Data related to identification, clinical history, preoperative features, and surgical outcomes were analyzed.Forty-four dogs (81 eyes), including 26 JRT and 18 LR, were enrolled in the study. Mean ages were 10.2 ± 3.2 years in JRT and 8.5 ± 3.7 years in LR. Twenty-eight (63.6%) were females and 16 (36.4%) were males. Most dogs (84.1%) presented with bilateral cataracts. Nuclear and cortical cataracts were the most prevalent type in both breeds (JRT: n?=?30, 61.2%; LR: n?=?16, 50.0%), although subcapsular cataracts were also frequent in LR (n?=?10, 31.3%). Significant differences in cataract location within the lens were detected between the two breeds (P?=?.002).Senile in JRT (n?=?7) and genetic in LR (n?=?7) were the most common etiologies. Concomitant ocular lesions were more frequent in dogs presented with cataracts in advanced stages, and included lens (n?=?18; JRT: n?=?15; LR: n?=?3) and retinal alterations (n?=?8; JRT: n?=?2; LR: n?=?6), and glaucoma (n?=?6; JRT: n?=?5; LR: n?=?1). Thirty-three animals (75.0%, 51 eyes) were submitted to phacoemulsification with intraocular lens placement. Of these, 28 eyes (54.9%; JRT: n?=?21; LR: n?=?7) were visual, 19 eyes (37.3%; JRT: n?=?11; LR: n?=?8) presented impaired vision and four eyes (7.8%; JRT: n?=?0; LR: n?=?4) were blind at last clinical record. Postoperative complications were detected in 11 eyes (21.6%), and were more frequent in dogs presented with cataracts in advanced stages.These results and the multifactorial nature of cataracts call for further studies to identify and characterize the variables in a broader assessment, including other breeds and influencing factors. 相似文献
29.
Tatiana A. Acosta‐Pachn Mariana L. Muzquiz‐Villalobos Sofia Ortega‐García Raúl O. Martínez‐Rincn 《Fisheries Oceanography》2019,28(2):203-211
Striped marlin (Kajikia audax) is an epipelagic fish distributed in oceanic and coastal waters of the Pacific Ocean. This species is usually found in warm and coastal waters with high primary productivity. The main goal of this study was to describe the spatial segregation of striped marlin by average Eye‐Fork length (EFL) in the eastern Pacific Ocean (EPO) and its relationship with environmental variables using EFL data obtained from tuna purse‐seining and Generalized Additive Models (GAMs). The model suggested that larger individuals of striped marlin were more likely to be found in waters with high Chlorophyll‐a concentration (>2 mg/m3) and with temperatures lower than 25°C, within a region known as the “cold tongue” and the Humboldt current system, while smaller individuals were more likely to be found in warmer and low productive areas within a region known as the “warm pool of the EPO.” We observed that set type caused a large variation on average EFL of striped marlin; larger fish were captured in sets associated with floating objects (natural and manmade), while smaller fish were captured in sets associated with dolphins. Despite this, our findings suggest that striped marlin has a latitudinal gradient in average EFL; larger individuals occurred predominantly south of 10°N, while smaller ones occurred predominantly in coastal waters between 10°N and 20°N, thus demonstrating a spatial segregation of the species affected by its maturity stage. 相似文献
30.
Iris Biton Sofia Shevtsov Oren Ostersetzer Yair Mani Shimon Lavee Benjamin Avidan Giora Ben‐Ari 《Plant Breeding》2012,131(6):767-774
The olive (Olea europaea) is one of the most important oleaginous crops of the Mediterranean basin. Increased demand for olive oil creates a need for new olive varieties to help meet the requirements of the global market. However, olive breeding has been handicapped by such varied challenges as a prolonged juvenile period, agrotechnical problems and insufficient genetic knowledge. The use of DNA markers has the potential to overcome these problems and increase the effectiveness of classical breeding programmes. In this study, co‐dominant polymorphic simple sequence repeats (SSRs) were used as markers to analyse the genetic relationships between several local and other ‘non‐native’ olive cultivars. Cluster analysis revealed four major groups among the 15 cultivars examined in this study. Table and oil cultivars were clustered in different groups. However, the clusters did not differentiate between cultivars of different geographical origins. In addition, we used the data gathered to analyse genetic relationships to evaluate the effects of heterosis in agricultural traits. Genetic distances between cultivars were determined based on the SSR genotype data and were used for evaluating the possible effects of heterosis in various F1 populations. Interestingly, phenotypic data of F1 progenies from crosses between different cultivars indicated the potential effects of heterosis as expressed in several traits. Genetic distance between parents was significantly correlated to F1 performance for three traits: percentage of dry fruit weight, oil content and commercial oil production. Thus, crosses between olive cultivars exhibiting relatively extensive genetic distances one from the other are expected to result in better progeny performance in future Olea breeding programmes. Our study linked assessment of biodiversity of commercial olive cultivars with the application of this information in olive breeding programmes for selection of specific parents to generate superior new cultivars. 相似文献