116 research outputs found
Evaluation of Egg Incubation Methods and Larval Feeding Regimes for North American Burbot
Incubation methods and larval feeding regimes were investigated for North American burbot Lota lota maculosa over 2 years. Three upwelling incubators were tested: 6.0‐L McDonald‐type jars, 2.0‐L pelagic egg jars, and 1.2‐L Imhoff cones. Larvae were allocated to five feeding regimes in year 1 (trial 1) and three feeding regimes in year 2 (trial 2). In trial 1, a live diet (marine rotifers Brachionus plicatilis and brine shrimp Artemia spp.) was administered from 11 d posthatch (dph) until introduction of a commercial diet at 21, 31, or 41 dph; the fourth treatment applied the commercial diet exclusively starting at 11 dph, and the fifth treatment used only the live diet. Trial 2 examined (1) exclusive use of live feed beginning at 16 dph; (2) use of live feed at 16–50 dph, which was combined with commercial feed at 31–50 dph, and use of only the commercial diet at 51–76 dph; and (3) use of the live diet at 16–50 dph, the addition of frozen brine shrimp at 31–50 dph, and use of the commercial diet at 51–76 dph. Approximate stocking densities for feeding trials were 25 larvae/L in trial 1 and 250 larvae/L in trial 2. Survival and total lengths (TLs) were measured at 52 dph in trial 1 and at 76 dph in trial 2. Incubation trials showed that Imhoff cones or pelagic egg jars significantly improved embryo survival relative to McDonald jars. Larvae fed a live diet for an extended time had significantly higher survival and TLs in both trials. Introduction of a commercial diet at 31 or 41 dph after live‐diet feeding was successful. This study provides a basis for further development of burbot aquaculture
Recommended from our members
Kootenai River Fisheries Investigation; Stock Status of Burbot, 2003-2004 Annual Report.
The main objective of this investigation was to monitor movement and spawning activity of burbot Lota lota in the Kootenai River, Idaho and British Columbia, Canada during the winter of 2003-2004. Due to low precipitation and snow pack, as well as low levels of Lake Koocanusa, the U.S. Army Corps of Engineers refrained from releasing discharges >113 m{sup 3}/s from Libby Dam for most of the winter. This situation provided suitable conditions for burbot migration and spawning in the mainstem river. Hoop nets captured 19 burbot, which ranged from 447 mm to 760 mm TL (mean = 630 mm) and weighed from 420 g to 4,032 g (mean = 1,937 g) with a mean W{sub r} of 99. One burbot (burbot 214) was captured for the fifth time since its first capture in 2000, and each capture was near Ambush Rock (rkm 244.4-244.8). Eleven burbot were tagged with five-month duration external sonic transmitters, and a 12th burbot, tagged with a 14-month transmitter, has been monitored since 2001. During the post-spawn period, three sonic-tagged burbot exhibited downstream and sedentary movement patterns, while five remained at Ambush Rock. Concentrations of tagged burbot near Ambush Rock (rkm 244.5) during January and February 2004 (eight tagged fish) may suggest that this area is critical spawning habitat. The appearance of burbot at Ambush Rock during the spawning period and upstream movements of tagged fish (PIT and sonic tagged) in previous years during the low discharges help validate results suggesting that discharges <113 m{sup 3}/s will permit burbot migration and may increase spawning habitat. Though it seems apparent that the Ambush Rock area is an important burbot spawning ground, no adult burbot were recaptured after the spawning period and no burbot larva were caught, despite considerable sampling efforts during the winter of 2003-2004
Characterization of a heat resistant beta-glucosidase as a new reporter in cells and mice.
BACKGROUND: Reporter genes are widely used in biology and only a limited number are available. We present a new reporter gene for the localization of mammalian cells and transgenic tissues based on detection of the bglA (SYNbglA) gene of Caldocellum saccharolyticum that encodes a thermophilic beta-glucosidase. RESULTS: SYNbglA was generated by introducing codon substitutions to remove CpG motifs as these are associated with gene silencing in mammalian cells. SYNbglA expression can be localized in situ or detected quantitatively in colorimetric assays and can be co-localized with E. coli beta-galactosidase. Further, we have generated a Cre-reporter mouse in which SYNbglA is expressed following recombination to demonstrate the general utility of SYNbglA for in vivo analyses. SYNbglA can be detected in tissue wholemounts and in frozen and wax embedded sections. CONCLUSIONS: SYNbglA will have general applicability to developmental and molecular studies in vitro and in vivo.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are
Recommended from our members
Predictors of Plasma Concentrations of DDE and PCBs in a Group of U.S. Women.
We evaluated predictors of plasma concentrations of dichlorodiphenyldichloroethylene (DDE), a metabolite of dichlorodiphenyltrichloroethane (DDT), and polychlorinated biphenyls (PCBs) in a group of 240 women, controls from a breast cancer case-control study nested in the Nurses' Health Study. We considered personal attributes such as age, serum cholesterol, region of residence, adiposity, lactation, and dietary intake. DDE levels increased 0.17 ppb/year of age ( = 0.0003), and PCBs increased 0.08 ppb ( = 0.0001). DDE and PCBs increased 0.20 ( = 0.02) and 0.13 ppb ( = 0.001), respectively, per 10 mg/dl serum cholesterol. Women living in the western United States had higher levels of DDE (mean = 11.0 ppb; = 0.003), and women in the Northeast and Midwest had higher levels of PCBs (mean = 5.6 ppb; = 0.0002) as compared to women from other parts of the country (mean DDE = 6.3; mean PCBs = 4. 5 ppb). Levels of DDE could not be predicted from consumption of meat, fish, poultry, dairy products, vegetables, fruits, and grains. There was a positive association between fish consumption and PCB concentrations among women in the Northeast and Midwest. Using data from the cases in the nested case-control study to assess the predictive ability of the models, we confirmed that the most reliable predictors of DDE were age and serum cholesterol, and the most important predictors of PCBs were age, serum cholesterol, and residence in the Midwest or Northeast. The null results for the majority of the food variables suggest that specific dietary factors, other than fish, are not currently a substantial contributor to human exposure to DDE and PCBs
Current Welfare Problems Facing Horses in Great Britain as Identified by Equine Stakeholders
Despite growing concerns about the welfare of horses in Great Britain (GB) there has been little surveillance of the welfare status of the horse population. Consequently we have limited knowledge of the range of welfare problems experienced by horses in GB and the situations in which poor welfare occurs. Thirty-one in-depth interviews were conducted with a cross -section of equine stakeholders, in order to explore their perceptions of the welfare problems faced by horses in GB. Welfare problems relating to health, management and riding and training were identified, including horses being under or over weight, stabling 24 hours a day and the inappropriate use of training aids. The interviewees also discussed broader contexts in which they perceived that welfare was compromised. The most commonly discussed context was where horses are kept in unsuitable environments, for example environments with poor grazing. The racing industry and travellers horses were identified as areas of the industry where horse welfare was particularly vulnerable to compromise. Lack of knowledge and financial constraints were perceived to be the root cause of poor welfare by many interviewees. The findings give insight into the range of welfare problems that may be faced by horses in GB, the contexts in which these may occur and their possible causes. Many of the problems identified by the interviewees have undergone limited scientific investigation pointing to areas where further research is likely to be necessary for welfare improvement. The large number of issues identified suggests that some form of prioritisation may be necessary to target research and resources effectively
Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis
BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London
Phosphorylation of GFAP is associated with injury in the neonatal pig hypoxic-ischemic brain
Glial fibrillary acidic protein (GFAP) is an intermediate filament protein expressed in the astrocyte cytoskeleton that plays an important role in the structure and function of the cell. GFAP can be phosphorylated at six serine (Ser) or threonine (Thr) residues but little is known about the role of GFAP phosphorylation in physiological and pathophysiological states. We have generated antibodies against two phosphorylated GFAP (pGFAP) proteins: p8GFAP, where GFAP is phosphorylated at Ser-8 and p13GFAP, where GFAP is phosphorylated at Ser-13. We examined p8GFAP and p13GFAP expression in the control neonatal pig brain and at 24 and 72 h after an hypoxic-ischemic (HI) insult. Immunohistochemistry demonstrated pGFAP expression in astrocytes with an atypical cytoskeletal morphology, even in control brains. Semi-quantitative western blotting revealed that p8GFAP expression was significantly increased at 24 h post-insult in HI animals with seizures in frontal, parietal, temporal and occipital cortices. At 72 h post-insult, p8GFAP and p13GFAP expression were significantly increased in HI animals with seizures in brain regions that are vulnerable to cellular damage (cortex and basal ganglia), but no changes were observed in brain regions that are relatively spared following an HI insult (brain stem and cerebellum). Increased pGFAP expression was associated with poor neurological outcomes such as abnormal encephalography and neurobehaviour, and increased histological brain damage. Phosphorylation of GFAP may play an important role in astrocyte remodelling during development and disease and could potentially contribute to the plasticity of the central nervous system
A manually annotated Actinidia chinensis var. chinensis (kiwifruit) genome highlights the challenges associated with draft genomes and gene prediction in plants
Most published genome sequences are drafts, and most are dominated by computational gene prediction. Draft genomes typically incorporate considerable sequence data that are not assigned to chromosomes, and predicted genes without quality confidence measures. The current Actinidia chinensis (kiwifruit) 'Hongyang' draft genome has 164\ua0Mb of sequences unassigned to pseudo-chromosomes, and omissions have been identified in the gene models
- …