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11.
In 2011, a Diarrhetic Shellfish Poisoning (DSP) outbreak occurred in British Columbia (BC), Canada that was associated with cooked mussel consumption. This is the first reported DSP outbreak in BC. Investigation of ill individuals, traceback of product and laboratory testing for toxins were used in this investigation. Sixty-two illnesses were reported. Public health and food safety investigation identified a common food source and harvest area. Public health and regulatory agencies took actions to recall product and notify the public. Shellfish monitoring program changes were implemented after the outbreak. Improved response and understanding of toxin production will improve management of future DSP outbreaks.  相似文献   
12.
The purpose of the present study was to investigate the feasibility of improving the synchronisation of lambing after oestrus synchronisation and artificial insemination (AI). To this end, low doses of dexamethasone 21-isonicotinate (DEX) alone or in combination with prostaglandin F2a (PG) were used in five treated groups (n = 20 each) and one control group (n = 136) of Chios ewes. On day 143 of pregnancy 1.5 mg DEX was given in Group 5, while on day 146 the following treatments were applied: 0.0375 mg PG in Groups 4 and 5, and 1, 1.5 and 2 mg of DEX in ewes of Groups 1, 2 and 3, respectively. The control ewes received no treatment. The 1.5 and 2 mg dose of DEX was more effective in synchronising labour as regards the treatment to lambing interval and the proportion of ewes that gave birth within 3 days. However, obstetrical manipulations were needed, and dead lambs were born when 2 mg DEX was used. It was concluded that lambing can be safely synchronised in Chios ewes with 1.5 mg DEX given on day 146, without affecting the viability of lambs and without parturition complications.  相似文献   
13.
The fillet fatty acids (FAs) and volatile compounds (VCs) of gilthead sea bream, fed either fish oil‐based diet (FO) or plant oils (PO), were studied in dorsal and ventral fillet parts over a 12‐day ice storage. Fillet FA reflected the FA composition of the respective diets. Monounsaturated FAs were reduced with storage, while no FA differentiations occurred between fillet parts. VCs varied between diet treatments, with food chain‐transported compounds (α‐pinene and dimethylsulphide) showing higher abundance in the FO group. VCs proposed as fish spoilage indicators (trimethylamine, pentanal, propanal, 3‐methylbutanal and 1‐penten‐3‐ol) increased with storage, while concentration of carbon disulphide associated with fresh fish aroma decreased during the same period. VCs varied between fillet parts, with ventral part exhibiting higher concentrations in fat‐soluble (terpenes, aromatic hydrocarbons) and spoilage‐associated VCs. Sensory analysis revealed no significant differences between diet groups with the exception of fattiness, which was found significantly higher in the plant oil group.  相似文献   
14.
In an attempt to trace the origins of the science of ichthyology, we studied Aristotle's zoological works (21 books in total), aiming to give an exhaustive catalogue of his fishes, suitable for use by modern marine biologists, and to evaluate the great philosopher's knowledge of fish biology. Our investigation yielded 135 ichthyonyms used to describe 109 individual fish taxa (13 fishes had multiple names) and 12 terms that corresponded either to fish developmental stages or behavioural patterns. Because of the variable amount of information given in the texts, 54 fishes were identified to species or genus level, 24 fishes to higher categories (family, order), 27 fishes could only be classified as Actinopterygii or Elasmobranchii, while four could not be classified at all. Among the most easily recognizable fishes were Lophius spp., Conger conger, Muraena helena, Anguilla anguilla and Mugil cephalus. The latter two and the tunas (Τhunnus spp.) were the most frequently recorded fishes. Aristotle's inquiry was not limited or focused on fish that were of human interest, but he also reported or described species that fascinated him by their peculiar life history. He was interested in a wide array of aspects of fish biology ranging from body structure and function, reproduction and development to fish feeding habits, migrations and diseases. As evidenced by his work, Aristotle should be considered the first ichthyologist, preoccupied with the zoological, scientific study of fish, and a review of his writings can prove useful for current ichthyological research.  相似文献   
15.
Two feeding trials examined the replacement of fishmeal (FM) with poultry by‐product meal (PBM) in the diet of juvenile Sparus aurata. In Feeding trial I (100 days), three diets were formulated, where FM protein was replaced by 50% (PBM50) and 100% (PBM100) PBM, while in Feeding trial II (110 days), four diets were formulated using the same FM control diet, but FM was replaced at lower levels: 25% (PBM25), and 25% (PBM25 + ) and 50% (PBM50 + ) with the supplementation of lysine and methionine amino acids. PBM protein can successfully replace 50% of FM protein in the diet of Saurata without adverse effects on survival, feed intake, growth performance and feed utilization, given that the diet is balanced with lysine and methionine. The proximate composition of body and muscle was unaffected by the diet, but the total FM replacement resulted in reduced lipid and energy contents in fish. A fifty per cent FM replacement by PBM did not affect haematological parameters indicating a good fish health. Similarities in trypsin and chymotrypsin activities with FM‐fed fish suggest a high digestibility of PBM. High dietary levels of PBM reduced the liver gene expression of GH/IGF axis and of cathepsin D suppressing fish growth and modulating the protein turnover.  相似文献   
16.
We present novel dynamic mixture models for the monitoring of bumblebee populations on an unprecedented geographical scale, motivated by the UK citizen science scheme BeeWalk. The models allow us for the first time to estimate bumblebee phenology and within-season productivity, defined as the number of individuals in each caste per colony in the population in that year, from citizen science data. All of these parameters are estimated separately for each caste, giving a means of considerable ecological detail in examining temporal changes in the complex life cycle of a social insect in the wild. Due to the dynamic nature of the models, we are able to produce population trends for a number of UK bumblebee species using the available time-series. Via an additional simulation exercise, we show the extent to which useful information will increase if the survey continues, and expands in scale, as expected. Bumblebees are extraordinarily important components of the ecosystem, providing pollination services of vast economic impact and functioning as indicator species for changes in climate or land use. Our results demonstrate the changes in both phenology and productivity between years and provide an invaluable tool for monitoring bumblebee populations, many of which are in decline, in the UK and around the world. Supplementary materials accompanying this paper appear online.  相似文献   
17.
The enantiomeric naphthoquinones alkannins and shikonins (A/S) have been established as potent wound healing agents. The purpose of this study was to evaluate the effectiveness of an A/S based ointment for humans on second intention wound healing in the dog, as compared to wound flushing with Lactated Ringer's solution (LRS). Ten mixed breed dogs, aged 2 to 5 y, were used. One 2.5 × 2.5 cm full-thickness skin defect was created on the lateral aspect of each arm for subjective evaluation, laser-Doppler flowmetry (LDF), and planimetry. Additionally, 3 matching 2 × 2 cm wounds were created on opposite sides of the dorsal midline for histologic evaluation. Wounds were treated once daily with the A/S based ointment on the right side and by flushing with LRS on the left until healed (about 20 d). During the healing process, tissue perfusion (mean LDF value) was found to be significantly higher on the side treated with the A/S based ointment compared with the LRS-treated side. Histologically, angiogenesis (on days 4 and 11), collagen production score (on days 4, 11, and 20), and epithelial thickness score (on day 11) were significantly higher in the wounds treated with the A/S based ointment. Wound size, as evaluated by planimetry, decreased significantly from day 0 to day 20 on both sides, but no significant differences were found between the A/S based ointment and LRS-treated wounds.  相似文献   
18.
The aim of this study was the detailed characterization of the phenolic composition and the determination of the antioxidant activity of the Bord? grape (Vitis labrusca) cultivated in South Brazil. The edible parts of Bord? grapes (flesh and skin) contained 1130 mg/kg of total phenolic compounds (as gallic acid), mainly located in the skins. Anthocyanin content in the skins was high, largely as 3,5-diglucosides (1359 mg/kg, as malvidin 3,5-diglucoside). Total flavonols accounted for 154 μmol/kg, mainly located in the skins and with myricetin 3-glucoside as the principal flavonol in both grape parts. Very low amounts of flavan-3-ol monomers and dimers and low amounts of polymeric proanthocyanidins, with a composition similar to that reported for V. vinifera grape varieties, were found in Bord? grape skins. Hydroxycinnamic acid derivatives mainly derived from caffeic acid and were found in the skins in high amounts, ten times higher than in the flesh (total amount: 483 μmol/kg). Finally, the Bord? grape cultivar can be considered a high resveratrol producer (10.91 mg/kg) and also exhibited a high value of total antioxidant capacity (37.6 ± 1.0 mmol/kg, as Trolox).  相似文献   
19.
20.

The nematode species Meloidogyne incognita infects a large variety of cultivated crops and is one of nature’s most notorious pests. One cultivated plant which is prone to M. incognita infestation is the tomato. Knowing that in A. thaliana the PIN auxin efflux transporters distribution is being altered upon early invasion by M. incognita, the PIN1 allocation patterns in the giant cells of tomato plants after 15 and 25 days of infection were investigated. PIN1 was absent from the giant cells’ membrane in both assessment timings examined, indicating the maintenance of a local auxin maxima, which was also supported by IAA immunodetection. PIN1 distribution pattern could be attributed on either the nematodes nutritional needs throughout its life cycle or due to the tomato plants differential responses upon M. incognita infection.

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