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81.
  • 1. The lagoon fishery of Rodrigues has considerable socio‐economic importance; however, catches have declined by 50% in recent years. The bluespine unicornfish, Naso unicornis (Forsskål 1775) is an important component of the fishery.
  • 2. To begin to assess whether marine reserves might benefit this species, sonic telemetry was used to track individual fish in one of Rodrigues' four marine reserves. Seven unicornfish were caught in the Grand Bassin reserve and tagged with abdominally implanted acoustic tags.
  • 3. Over a period of 57 days their locations were determined up to 21 times using a hand held hydrophone and receiver. Individual minimum convex polygon (MCP) home ranges varied from ~10 000 m2 to ~274 000 m2 and were not correlated with fish size. Kernel estimates of core areas (50% utilization distribution) varied from ~5000 m2 to ~175 000 m2. All seven fish stayed within the marine reserve and the largest home range occupied less than ~2% of the area of the marine reserve.
  • 4. Fish remained on the outside edge of the lagoon on the shallow reef slope and among coral patches. These findings suggest that bluespined unicornfish biomass and numbers should increase if the Grand Bassin marine reserve is closed to fishing. Long‐term monitoring will, however, be required to demonstrate this outcome. Copyright © 2010 John Wiley & Sons, Ltd.
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82.
BACKGROUND: In dogs, treatment of pulmonic valve stenosis (PS) with pulmonary balloon valvuloplasty (PBV) is a viable method to decrease the pressure gradient across the valve. However, to the authors' knowledge, the variables that influence the selection of the correct balloon size for the procedure have not been explored. Moreover, the lesions caused by the procedure have not been detailed. HYPOTHESIS: Variables that influence the measurement of the annulus could affect selection of the balloon size. We sought to determine the effects of treatment when the balloon-to-annulus ratio (BAR) was or > 1.3, but within the recommended range of 1.2-1.5, regardless of whether dilation was performed with single or double balloon technique. ANIMALS: Twenty-five Beagles with PS were studied. METHODS: Inter- and intra-observer variability, echocardiography versus angiocardiography, and systolic versus diastolic timing were evaluated for the BAR. Assessment of right ventricular (RV) pressure, Doppler gradient, stenotic valve area, and RV wall thickness were compared before and 1, 90, and 180 days after treatment. Postmortem examination of the heart was done. RESULTS: Significant correlations existed in measurement of the annulus; however, variation existed that would change balloon size. Improvement in the degree of PS was significant regardless of the BAR or single or double ballooning. In the most severely affected dogs, continued improvement was noted on day 90. Postmortem examination revealed tears in the commissures and the valve leaflets. CONCLUSIONS: Multiple factors influenced determination of the BAR and a range of 1.2-1.5 was effective without detrimental consequences. Dogs with severe PS had continued decrease in RV pressure 3 months after treatment.  相似文献   
83.
The purposes of this study were 2-fold: (1) to determine the prevalence of splintered QRS complexes (Rr', RR', rR', rr') and other electrocardiographic abnormalities in dogs and cats with congenital right atrioventricular valve malformation (RAVM) and (2) to determine if the Labrador Retriever was at greater risk for RAVM and splintered QRS complexes. EKGs from 39 dogs and 6 cats with echocardiographically diagnosed RAVM were studied retrospectively. Splintered QRS complexes were commonly found in affected Labrador Retrievers (9 of 19, 47%), non-Labrador Retrievers (12 of 20, 60%), and cats (4 of 6, 67%). Right ventricular enlargement was most commonly detected by precordial leads (CV6LL[V2], CV6LU[V4]) in the dogs and by the standard limb leads in the cats. Arrhythmias were uncommon. The Labrador Retriever was significantly overrepresented (P < .001) in the RAVM group when compared to the general hospital population (50% versus 8%). Males were also significantly overrepresented ( P < .01). It was concluded that splintered QRS complexes are a distinctive and common electrocardiographic finding in dogs and cats with RAVM. Moreover, this congenital cardiac defect is most common in the Labrador Retriever, although this breed does not have proportionately more or less splintering of the QRS complexes than other breeds.  相似文献   
84.
Charles R.  Pugh  DVM  MS  Jeffrey A.  Wortman  VMD  PhD  H. Mark  Saunders  VMD  Darryl N.  Biery  DVM  W. Harker  Rhodes  VMD  MS  Sydney M.  Evans  VMD  MS  Lynn M.  Walker  VMD  Pamela  Green  DVM  Rosa  Mendez-Aguillar  DVM  Joan  Regan  VMD 《Veterinary radiology & ultrasound》1995,36(6):485-492
The relative quality and speed of a new ultraviolet-emitting screen, ultraviolet-sensitive film rare-earth system (DuPont Ultra-Vision®) was compared to an orthochromatic rare-earth system (Kodak Lanex®) in a clinical trial. Seven different sets of radiographs of a human foot phantom, or actual canine anatomical structures (tarsus, pelvis, skull, chest, abdomen) were evaluated independently by radiologists, radiology residents and technicians who were unaware of the screen/film combinations used. The 400-speed, Ultra-Vision® Rapid/UVG screen/film combination produced supervisor image detail compared to blue/green emitting 400 and 200-speed screen/film combinations. The image detail of the Ultra-Vision® Rapid/UVG system was nearly equivalent to that produced using a 100-speed, fine-detail blue/green emitting screen/film combination. A 200-speed Ultra-Vision® system was also tested and produced thoracic and abdominal radiographs of equivalent to slightly supervisor quality than those produced using blue/green emitting system.  相似文献   
85.
A survey to determine the nematode species in rural chickens reared extensively was carried out in six districts of Zimbabwe. Two-hundred-and-seventy chickens were randomly collected from the districts and processed for helminth recovery. One genus and 10 species were identified from the gastrointestinal tract but no parasites were found in the respiratory tract and eyes. Skrjabinocerca sp., Capillaria obsignata, Capillaria contorta and Trichostrongylus tenuis are new records in Zimbabwe. Allodapa brumpti and Tetrameres americana were the most common species with a prevalence of 64.8% and 64.1%, respectively.  相似文献   
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Twelve Tuli weaner steers aged 1 year were randomly subdivided into three groups of four animals and infected with different doses of Calicophoron microbothrium metacercariae. Each animal in Group I received a low dose (LD) of 5 000 metacercariae, Group II a medium dose (MD) of 15 000 metacercariae, Group III a high dose (HD) of 25 000 metacercariae and one additional animal was kept as an uninfected control (C). After infection, one animal from each group was slaughtered on Day 28, 42, 56 and 84 post infection (pi) and samples from the ileum, jejunum, duodenum, abomasum and the rumen were collected for histopathological and cytological examination. On Day 28 pi, the gross pathological lesions observed in the duodenum of the LD and the MD animals were similar and comprised duodenal thickening, corrugation, hyperaemia, petechiation and ulceration. In the HD animal the duodenal lesions were similar but more severe. The abomasal folds were severely oedematous in the MD group and nearly occluded the abomasal lumen. Moderate oedema of the abomasal folds was also present in the LD and HD animals. The gross pathological lesions regressed in all the infected groups with increasing age of infection and had disappeared completely by Day 56 pi. On Day 28 pi the histopathological lesions in the duodenum and jejunum of the LD and MD groups were similar, comprising subtotal villous atrophy, hyperplasia of Brunner's glands and Peyer's patches and moderate infiltration of eosinophils, mast cells and a few globule leukocytes, basophils and lymphocytes in the lamina propria. The HD group had total villous atrophy, severe hyperplasia and cystic dilatation of Brunner's glands, which had expanded to cover the entire submucosa. On Day 42 pi the histopathological lesions were still present in the MD and the HD groups comprising subtotal villous atrophy and hyperplasia of Brunner's glands. Heavy infiltrations of eosinophils, moderate amounts of mast cells and a few basophils, globule leukocytes and lymphocytes were still present in the lamina propria of all three groups. On Day 56 pi, a few glands were still cystic in the MD and the HD groups. Moderate cell infiltrations were still present in the lamina propria of all the three groups and by Day 84 pi complete regeneration had occurred in all animals.  相似文献   
90.
Histopathological examination was performed on cutaneous biopsies from 900 dogs with skin lesions from Zimbabwe, collected from 1996 to 2000. Clinical data were collected from medical records. Sixty per cent (540/900) of the cases were tumours and 40% (360/900) were non-neoplastic inflammatory or degenerative diseases. Thirty different histological types of tumour were diagnosed. The prevalence of epithelial, mesenchymal, lymphohistiocytic and melanocytic tumours was 39.4%, 44.4%, 7.4% and 8.7%, respectively. The 10 most common tumours, comprising 73.7% of all cutaneous neoplasms, were mast cell tumours, squamous cell carcinomas, perianal gland adenomas, lymphomas, benign melanomas, haemangiosarcomas, sebaceous gland adenomas, fibrosarcomas, lipomas and malignant melanomas. The prevalence of various neoplasms, age of affected dogs and sites of occurrence were similar to surveys in other countries, except that in Zimbabwe there was a greater prevalence of lymphomas and of tumours associated with increased exposure to ultraviolet light (squamous cell carcinomas, haemangiosarcomas and melanomas). For all classes of tumours the sex of the dog did not have any significant influence on the likelihood of developing a tumour. For a dog diagnosed with a tumour located on the trunk, the tumour was significantly more likely to be an epithelial tumour than a non-epithelial tumour The occurrence of melanocytic tumours on the trunk was significantly lower than at other sites. Lymphohistiocytic tumours were 10 times more likely to occur at multiple locations as opposed to single locations.  相似文献   
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