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991.
The early life stages of the Antarctic silverfish (Pleuragramma antarctica), an important prey species for higher predators in the Southern Ocean ecosystem, dominate the larval fish assemblages of the Bransfield Strait, one of the most important areas for larval retention off the Antarctic Peninsula. Nevertheless, the spatial location of areas where they were spawned and the timing of larval hatching remain unknown. By linking Lagrangian particle tracking simulations with age data obtained using otolith microincrements from fish caught north of Joinville Island in a pelagic survey, we estimated the distribution of hatch dates and subsequent growth rates of silverfish reaching the Bransfield Strait, and predicted the areas where they were spawned. Larval hatching peaked during the last week of December, and the inner shelf and shelf break, east of the Larsen Ice shelf, were the dominant areas predicted to contribute to larval assemblages in the Bransfield Strait. Over simulated periods of 600–630 days, 35–40% of particles remained within the Bransfield Strait, suggesting an important source of supply to higher predators feeding off the northern Antarctic Peninsula. The daily growth rate at the mean size of 22.3 mm was 0.18 mm, corresponding to a daily change in size of approximately 0.82% standard length (SL), and large variability in growth rate suggested a wide range of environmental conditions experienced during the period of advection from the spawning areas. These results provide spatial predictions that can be tested empirically in future studies, using the simulated trajectories to inform sampling design and spatial coverage.  相似文献   
992.
993.
The efficacy of different silage additives on different mixtures of white lupin and spring wheat was investigated in four separate trials. The bicrop was harvested 96 days (trials 1 and 2) and 110 days (trials 3 and 4) after sowing. For each maturity stage, two mixtures of white lupin and spring wheat were reformed in the ratios of 1:2 and 2:1 on fresh matter (FM) basis respectively. The crops were treated with formic acid (FA), sodium nitrite–hexamine mixture (NaHe) or homofermentative lactic acid bacteria (LAB). The control silage was made without additive. Additives were not able to improve the quality of white lupin–wheat silage in all trials, compared with untreated silage. The treatment with LAB showed good results only at the first stage of crop maturity with sufficient amounts of water‐soluble carbohydrate in the pre‐ensiling crops. The FA treatment showed elevated butyric acid levels in all trials, which suggests that the FA application level used (4 L t?1 FM, 100% FA) was insufficient to decrease pH enough for preventing the growth of clostridia and butyric acid fermentation. NaHe was the only additive that was able to inhibit the activity of clostridia in all trials.  相似文献   
994.
995.
Flow cytometry is considered the only reliable method for the separation of X and Y chromosome bearing spermatozoa in equines. The MoFlo SX DP sorter is highly efficient, allowing the production of foals of the desired sex. However, to achieve acceptable pregnancy rates the currently used protocol requires working with fresh semen obtained close to, or at, the sorting facility. An alternative protocol was tested during two consecutive breeding seasons. Fresh stallion semen was cooled for 20 h, during which staining with Hoechst 33342 took place. On the following day, this sample was flow sorted and compared with spermatozoa from the same ejaculate that had been sexed on the previous day. All sperm parameters evaluated remained unchanged when fresh sorted and refrigerated sorted semen were compared. Pre‐sorting storage at 5°C did not alter sperm velocities nor kinetics, viability or membrane permeability, production of reactive oxygen species, mitochondrial membrane potential or DNA fragmentation index of the sorted sample. The findings open for the possibility of using semen from stallions housed far from the sorting facilities. Processed and stained sperm could be shipped refrigerated on the previous day, sorted and inseminated on the next day.  相似文献   
996.
Veiled chameleons (Chamaeleo calyptratus) and panther chameleons (Furcifer pardalis) are the most popular chameleons over the world, and consequently, two of the most frequent species presenting to veterinary practices. However, published studies on normal ultrasonographic anatomy for these lizards are currently lacking. The objectives of this prospective anatomic study were to develop an ultrasound protocol for evaluation of the coelomic cavity in these species and describe the normal ultrasonographic anatomy of the coelomic organs. Seventeen healthy veiled chameleons and 15 healthy panther chameleons were included. A linear 18 MHz transducer was used. Chameleons were sedated and restrained in right lateral recumbency by an assistant. Longitudinal and transverse images were acquired, and authors recorded qualitative and quantitative ultrasonographic characteristics of the coelomic structures. The kidneys, liver, caudal vena cava, hepatic veins, portal vein, gallbladder, wall of the stomach and intestine, gonads and, when distended, urinary bladder could be visualized during ultrasonography of the coelomic cavity in both species. The spleen, pancreas, and adrenal glands could not be identified. Findings from the current study supported the use of ultrasonography for veiled chameleons (Chamaeleo calyptratus) and panther chameleons (Furcifer pardalis) with suspected intracoelomic diseases and provided normal reference information for future studies of these chameleon species.  相似文献   
997.
Objectives : To determine which types of tumour occur in cats up to the age of 12 months based on biopsies submitted to Idexx Laboratories, Wetherby, UK. Methods : Retrospective review of histopathological diagnoses of tumours in cats up to the age of 12 months from biopsies received between September 1993 and March 2008. Results : A total of 4196 submissions from cats 12 months old or younger were identified; 233 biopsies (6%) were neoplastic and fulfilled the search criteria. Tumours were categorised as haematopoietic (n=73, 31%), malignant epithelial (n=44; 19%), malignant mesenchymal (n=38; 16%), benign epithelial (n=37; 16%), benign mesenchymal (n=30, 13%) and miscellaneous (n=11; 5%). The most frequent tumours were lymphoma (n=51; 22%), soft-tissue sarcoma (n=34; 15%), mast cell tumour (n=22; 9%) and squamous cell carcinoma (n=16; 7%). The most common tumour site was the skin and soft tissues (41% of tumours). In all, 164 neoplasms (70%) were malignant or had malignant potential. Clinical Significance : These data provide unique epidemiological information on a poorly characterised subgroup of feline cancer patients in the UK.  相似文献   
998.
A six-year-old cross breed dog was presented with a four-month history of seizure activity, which was unresponsive to anticonvulsive therapy and an acute deterioration in neurological status, evident as central blindness. Cyst-like structures and nodular enhancement within the subarachnoid space were shown on a magnetic resonance image (MRI) scan. Histopathological examination of brain tissue was consistent with meningeal carcinomatosis.  相似文献   
999.
1000.
Widdrol (1) was tested against the necrotrophic plant pathogens Botrytis cinerea and Colletotrichum gloeosporioides. While 1 was found to be inactive against C. gloeosporioides, it showed a selective and effective control of B. cinerea, significantly inhibiting the mycelial growth of the fungus at concentrations of 100 ppm and above. In addition, the biotransformation of 1 by both fungi was studied. Incubation with C. gloeosporioides and B. cinerea afforded four and one biotransformation products (2-6), respectively. Biotransformation with C. gloeosporioides was highly regioselective, yielding for the most part oxidation products at C-10: 10-oxowiddrol (2), 10beta-hydroxywiddrol (3), 10alpha-hydroxywiddrol (4), and 14alpha-hydroxywiddrol (5). The structures of all products were determined on the basis of their spectroscopic data, including coupling constants, two-dimensional NMR analysis (heteronuclear multiple quantum coherence, heteronuclear multiple bond correlation, and nuclear Overhauser enhancement spectroscopy), and nuclear Overhauser effect. The biotransformation products were then tested against B. cinerea and found to be inactive. These results shed further light on the structural modifications, which may be necessary to develop selective fungal control agents against B. cinerea.  相似文献   
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