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51.
To determine the dietary protein and energy requirements of juvenile largemouth bass, 1350 feed‐conditioned fishes (average weight 14.46 ± 0.81 g) were stocked in ninety 60‐L cages, set up in 1000‐L tanks at three cages/tank, and fed for 64 days with a dry, extruded feed containing six levels of crude protein (CP) (340–540 g kg–1, with increases of 40 g kg–1) and five levels of energy (150.7–171.7 kJ g–1 feed, with increases of 5.2 kJ). The trial was set up in a 6 × 5 factorial, completely randomized design (n=3). Weight gain (WG), daily feed consumption (DFC), feed conversion rate (FCR), protein efficiency ratio (PER), specific growth rate (SGR), protein and energy retention were recorded and evaluated. There was no interaction between feed energy and protein levels with all parameters evaluated. Data analysis by the broken line method showed that the minimum dietary requirement for maximum daily weight gain of 8.0 g kg–1 is 435.9 g kg–1 CP; the best feed conversion ratio (1.04:1) was attained with a minimum of 448.2 g kg–1 CP; a minimum of 162.1 kJ g–1; DFC was reduced as dietary protein and energy levels increased; dietary levels of 460–500 g kg–1 CP led to best PER (1.665); best values for protein (33.14 g 100 g–1) and energy (26.87 g 100 g–1) retention were observed for fish feeding on the 420 g kg–1 CP ration. Limits of energy to protein ratio to feed largemouth bass are 25.01 and 26.89 mg protein kJ–1, enabling feed conversion ratios of 0.96–1.10.  相似文献   
52.
  1. Explorations of the Mediterranean deep sea using remotely operated vehicles have shown that the sea bed hosts rich habitats, supporting high biodiversity. However, there have been only a few studies dealing with the southern part of the basin, leading to limited protection and conservation efforts in this area.
  2. This study aimed to explore the sea bed off Linosa Island (Sicily Channel, southern Mediterranean Sea), which is considered a ‘sentinel area’ for alien species and global environmental changes owing to its geographic position, thus deserving special attention.
  3. Remotely operated vehicle surveys, carried out in 2016 and 2017, were analysed to provide the first ecological characterization of benthic assemblages at depths −19 – −384 m around Linosa Island.
  4. Communities were dominated by three priority habitats, amounting to 39% of the almost 5 km of the sea floor that was surveyed. These are represented in the euphotic zone by Posidonia oceanica meadows and, at greater depth, by newly discovered dense coral forests and extended rhodolith/maërl beds. Sixteen habitat-forming species included in the Red List of the International Union for Conservation of Nature (e.g. gorgonians Eunicella cavolini and Paramuricea clavata, and black corals Antipathella subpinnata and Leiopathes glaberrima) were recorded, as well as individuals of Sargassum sp. at −100 m depth.
  5. The volcanic island of Linosa represents a small, naturally preserved area, with very limited human pressure, hosting rich marine benthic biodiversity. Given the high species and habitat richness, we recommend its inclusion in the Special Protected Areas of Mediterranean Importance project (United Nations Environment Programme) and suggest a redefinition of the existing marine protected area extension.
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53.
The computed tomography (CT) imaging findings of a celiacomesenteric trunk (CMT) in a 1‐year‐old dog with primary hypoplasia of the portal vein (PHPV) are described. Computed tomography angiography revealed acquired porto‐systemic shunts secondary to portal hypertension and a common origin of the celiac and cranial mesenteric arteries. The imaging findings and the association of a CMT with other vascular diseases have never been reported in dogs. The recognition of this rare arterial anomaly should prompt to investigate possible concurrent vascular diseases and may influence the planning of abdominal surgeries.  相似文献   
54.
Genetic Resources and Crop Evolution - Sorghum [Sorghum bicolor (L.) Moench] is a subsistence crop and the main food for populations in arid or semiarid regions and it is appreciated for the...  相似文献   
55.
56.
Ovine enzootic abortion is an infectious and contagious disease clinically characterized by abortion and weak neonates, affecting sheep and goats. The etiological agent is Chlamydophila (C.) abortus, which is considered one of the most common animal pathogens of small ruminants; it has important economic implications and represents a significant zoonotic risk. Clinical diagnosis is often difficult because the clinical signs and the pathological lesions are not specific for C. abortus infection, in fact they can also be observed as a result of infections with other abortifacient agents. Moreover, the involvement of the laboratory is necessary to perform the definitive diagnosis. One hundred and seventeen vaginal swabs from sheep with clinical signs related to chlamydial infection were examined by a PCR-RFLP assay that demonstrated high specifity and sensitivity. Six samples were positive for C. abortus. Vaginal swabs are easy to handle and allow to deal with biohazardous material in safety conditions.  相似文献   
57.
Urinary bladder torsion is rare in dogs. It is characterised by rotation of the organ along its longitudinal axis and is potentially life‐threatening because of urinary flow obstruction with subsequent urine retention, hydroureter, hydronephrosis and azotaemia. This report describes the computed tomographic features of urinary bladder torsion in two dogs. In both cases, the hallmark indicative of torsion was the “whirl sign,” originating from the twisted pelvic urethra and urinary bladder neck encircling the ureters, blood vessels and bladder ligaments in a characteristic spiral pattern. The imaging features correlated well with surgical findings, demonstrating high sensitivity of computed tomography in the preoperative diagnosis of urinary bladder torsion.  相似文献   
58.
  • 1. European eel (Anguilla anguilla) is recognized as a critically endangered species in the northern hemisphere. Threats such as overfishing or pollution are well known as risks for eel populations. However, much less is known about the impact of introduced fish on European eels. In particular, introduced large‐bodied predators could become new predators to eels.
  • 2. The potential impact of European catfish (Silurus glanis L) on an eel population in the Camargue, southern France was studied using a combination of stable isotope and gut content analyses.
  • 3. Only large‐bodied catfish (>500 mm) can consume numerous fish prey. However, catfish mostly consumed crayfish (Procambarus clarkii), these prey items being found in 79% of the guts of the largest individuals. Eel was absent from the dissected catfish guts. A mixing model based on Bayesian inference revealed that catfish diet included only 5% (0–8.5%) of marine sources (both eel and mullet).
  • 4. While local economic interests prompted ecological studies to assess whether catfish exerted a new and strong predatory pressure on eel, this study found that European catfish behaved as an opportunistic omnivore, and as such was not a direct threat as a predator on eel populations in the Camargue. Copyright © 2011 John Wiley & Sons, Ltd.
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59.
Four fertilizer treatments were applied to 10 cultivars of durum wheat (Triticum turgidum var. durum L.) in three seasons of designed field trials. The fertilizer treatments were N0S0 ‐ neither N nor S applied; N1S0 ‐ only N applied; N1S1 ‐ both N and S applied; N0S1 ‐ only S applied. It was found, through densitometric SDS‐PAGE, that the relative proportion of different gliadin components was influenced by the distinct regimes, even though our region in the center of the Argentinean Pampa is not considered to be deficient in soil S‐availability. The effects observed were more marked in one particular season of the three studied, were principally associated with the treatment expected to produce the maximum degree of grain S‐deficiency (N1S0), and were consistent with the hypothesis that the relative content of S‐poor gliadins increases under conditions of S‐deficiency, as has been found in related crops. Multivariate reverse‐phase high‐performance liquid chromatography (RP‐HPLC) analysis of samples from the season most affected generally supported these observations, but refined them in identifying quantitative differences between all four fertilizer treatments for the cultivars studied. These findings imply that differences in industrial quality might also be expected between the fertilizer treatments. RP‐HPLC also identified numerous genetically controlled qualitative differences in the gliadins between the cultivars studied, adding to previous published work on these cultivars based on SDS‐PAGE. These observations confirmed that one particular cultivar of very low gluten strength showed a gliadin profile markedly distinct from the remaining cultivars studied.  相似文献   
60.
Proton high‐resolution magic angle spinning nuclear magnetic resonance (1H HR‐MAS NMR) has been applied for the analysis of two cultivars of durum wheat produced in different Italian geographical areas. Furthermore, on the same samples, isotopic ratios were measured by mass spectrometry (IRMS). The application of chemometrics to these results permitted the discrimination of semolina by cultivar and geographical origin. A similar approach has been applied to the results obtained from chemical analyses. The comparison showed that NMR spectroscopy can provide a faster method for the detection of differences among the durum wheat semolina according to geographical and varietal origin. Furthermore, IRMS data are suitable to provide information about the geographical origin of samples. This present investigation is part of an extensive research project to find a scientific method capable of classifying wheat foods for the assignment of a “denomination of origin” trademark.  相似文献   
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