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81.
A 7-year-old, male, castrated, Labrador Retriever with a history of pancreatitis and inflammatory bowel disease presented for vomiting and anorexia. Serum biochemistry findings were indicative of cholestasis, hepatocellular insult, and decreased hepatic function. Ultrasound examination showed sediment and gas within the gallbladder, and a diagnosis of emphysematous cholecystitis was made. Emergency gallbladder resection was performed. Cytologic examination of bile fluid collected at surgery showed a mixed population of bacteria (bactibilia) together with fungal organisms consistent with Cyniclomyces guttulatus (previously known as Saccharomycopsis guttulatus). Similar fungal organisms were seen on a fecal smear. Bacteria cultured were normal gastrointestinal flora, supporting ascending infection; the fungal organisms were interpreted as incidental. Histopathology of the gallbladder indicated active (suppurative) and chronic (lymphocytic) cholecystitis and sections of liver tissue had evidence of chronic liver disease. A positive liver culture indicated concurrent bacterial hepatitis or cholangiohepatitis. Despite supportive care, the dog continued to decline and was euthanized 30 days later. Necropsy results confirmed end stage liver disease, but an initiating cause was not found. This case highlights the role of bactibilia in the development of acute cholecystitis and the unique cytologic appearance of C guttulatus as an incidental finding in bile fluid.  相似文献   
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Weed control is fundamental in plantations of valuable broadleaved species. The most common weeding techniques are repeatedly applied herbicides and removable plastic mulching, both raising environmental concerns. We studied the performance of these techniques on a hybrid walnut plantation, compared with three biodegradable mulch alternatives: a prototype bioplastic film, a layer of composted woodchips and a layer of ramial chips. The durability and effect of the treatments on tree performance (survival, growth, physiological traits) and soil features (moisture and temperature) were evaluated over 4 years. Herbicide yielded the best results, while all the mulching treatments provided better results than controls for nearly all the variables. The performance of plastic and bioplastic films was similar, suggesting that the latter could replace plastic mulching. The performance of the two chip mulches was similar and slightly below that of the films, probably because of the excessive thickness of the former (13–14 cm). In summary, biodegradable mulches showed high effectiveness in controlling weeds and so could offer an alternative to herbicide application and plastic mulching when these are contra-indicated technically (accessibility, repeatability), economically (labour cost), legally or environmentally.  相似文献   
84.
In some diseases-in particular, tree root infection-stages of infection and inoculum production level and timing are not readily observable because of uncertainty or time lags in symptom appearance. Here, we pose a criterion, based on relative hazard of disease symptoms, to discriminate between healthy and asymptomatic infected individuals. We design a statistical procedure to estimate the criterion for a 6-year survey of alder decline along a northeastern French river. Individual tree symptom hazard was modeled with Cox's regression model, taking estimation of local infection pressure as a risk factor. From an inoculum production experiment, we thereafter assessed the inoculum production level of target trees, including symptomatic and asymptomatic trees ranked according to their symptoms hazard. Using receiver operating characteristic methods, we first evaluated the criterion performance and determined the discrimination threshold to sort out asymptomatic individuals into healthy and infected. Then, we highlighted the fact that the infected asymptomatic trees were among the major inoculum producers whereas severely declining and dead trees were found to be poor inoculum sources.  相似文献   
85.
Grazing behavior, diet selection and weight gain of heifers (with or without social models) were assessed in an unfamiliar site containing high plant diversity. The study was performed within a tropical forest ecosystem containing a mixture of grass forb/herb, shrub and tree species. Ten inexperienced crossbred Bos taurus × Bos indicus heifers (7 ± 1 months old) were randomly assigned to one of two groups: naive or naive + social model (sm) and two experienced heifers (16 months old) were assigned to the second group. Naive heifers were bottle-nursed from days 2 to 90 after birth and began grazing at 1 month of age in tropical grass monocultures, while experienced animals had been foraging in sites containing a high diversity of plant species for 3 months prior to the study. Each group grazed in separate paddocks for a 12-week period during the rainy season, and animals were observed using focal sampling from 7:00 to 19:30 h to assess diet composition based on bite counts. Weight gain was assessed every 14 days. Paddocks contained from 1481 to 1789 kg/ha of herbaceous dry matter, enough to support the heifers throughout the study without affecting diet selection. Shrub and tree cover ranged from 55.2 to 58.4% across treatments. Bites per minute were adjusted to a log-scaled quadratic-plateau model and the curves showed no differences between treatments (P = 0.756). However, diet composition differed between groups (P < 0.001), with naive + sm heifers ingesting a greater proportion of trees (P < 0.001) and shrubs (P = 0.02), while naive heifers ingested more forb/herbs (P = 0.02); no difference in grass consumption was observed (P = 0.92). Heifers in both treatments consumed the same plant species (50 from 26 families). Over time, utilization of several plant species increased or decreased (P < 0.05), eventually leveling off for the remainder of the study. Although differences in diet composition were observed, they did not affect overall weight gain (117 and 113 g/day in the naive and naive + sm groups, respectively; P = 0.913). However, initial post-weaning weight loss was avoided in the naive + sm group. Social learning facilitates a higher use of shrubs and trees in tropical pastures containing a high diversity of plant species with different growth habits. As many plant species have high potential as forage, more effort should be placed on developing mechanisms to increase their dietary inclusion by cattle.  相似文献   
86.
BACKGROUND: Chemosterilisation with lufenuron bait stations is a recently developed technique that is being implemented for Ceratitis capitata Wiedemann control. The aim of this work was to evaluate the chemosterilising effect of lufenuron against four economically important Latin American fruit flies species: Anastrepha ludens (Loew.), A. obliqua Macquart, A. serpentina Wiedemann and A. striata Schiner (Diptera: Tephritidae) in order to design a similar strategy for their control. RESULTS: Sexually mature adults were treated by ingestion with concentrations ranging from 0.1 to 30.0 mg g?1 of lufenuron in the diet. In addition, conspecific crosses with only one of the sexes being treated (30.0 mg g?1) were performed in order to appraise the contribution of each sex to the sterilising effect. In all cases, fecundity was not affected by the treatments, as opposed to fertility where all Anastrepha species studied were significantly affected, although to different extents. The conspecific crosses showed that treated males of A. ludens, A. obliqua and A. serpentina were not able to transmit the sterility to their respective untreated females. Only in the case of A. striata did crossing treated males with untreated females significantly reduced egg hatch. CONCLUSION: Although further investigations are required, the present results demonstrate that the use of lufenuron for controlling A. striata could be potentially viable. Copyright © 2010 Society of Chemical Industry  相似文献   
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88.
In order to evaluate the effect of protein supplementation on the productive and reproductive performance of heifers, 45 Bos indicus × Bos taurus heifers, 673 ± 146 days of age and weighing about 340 kg, were divided into two groups. The control group (n = 23) continued without supplementation, but the supplemented group (SG; n = 22) received concentrate at a rate of 1% BW kg per day. Animals were adapted to the concentrate over a 15-day period and then supplemented for 30 days, after which estrus was synchronized using a progesterone implant. Back fat thickness (BFT) was assessed by ultrasound. The SG had better average daily weight gain than the nonsupplemented group (0.63 ± 0.16 vs. 0.51 ± 0.13 kg/day, P < 0.05) and tended to show a better percentage ovulation (P < 0.10, 77% vs. 57%, respectively). However, this tendency was not reflected in the final pregnancy rates. No differences were observed between groups in dry matter intake and body condition scores. SG with a high BFT (>0.70 cm) showed a better ovulation percentage than those with low BFT (<0.69 cm; P < 0.01). Additionally, the pregnancy rate of supplemented heifers with high BFT tended to be better than heifers with low BFT in this same group (67% vs. 30%, respectively, P < 0.10). It is concluded that protein supplementation improved reproductive performance and that ultrasonography to measure BFT may be used to estimate reproductive performance.  相似文献   
89.
Background: Cytoplasmic fragments derived from fragile neoplastic lymphocytes are common in samples of lymph nodes collected from dogs with lymphoma. These cytoplasmic fragments interfere with accurate gating of target cells and quantification protocols used for flow cytometry because of their variable size and expression of lymphoid cell surface antigens on their membranes. Objective: The aim of this study was to develop a method to efficiently exclude cytoplasmic fragments from flow cytometric analysis of canine lymph nodes in which lymphoma was present. Methods: Single‐cell suspensions of neoplastic cells were prepared from biopsy samples and fine‐needle aspirates of lymph nodes from 23 dogs with lymphoma. Suspensions were stained using a violet laser‐excitable (405 nm) membrane‐permeable DNA‐binding fluorescent dye (DyeCycle Violet [DCV]), incubated with antibodies against CD3, CD5, CD21, CD22, and CD45, and then stained with 7‐amino‐actinomycin D (7‐AAD), an argon‐excitable (488 nm) membrane‐impermeable DNA‐binding fluorescent dye. Multiparameter flow cytometry was used for analysis based on selective uptake and laser‐activated fluorescence of these dyes. Results: Cytoplasmic fragments, which were DCV‐negative and CD45‐positive, and dead cells, which were positive for 7‐AAD, were efficiently separated from neoplastic cells. Conclusion: Staining with DCV is a useful method to improve flow cytometric gating methods and quantitative analyses of lymph node samples from dogs with lymphoma.  相似文献   
90.
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