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41.
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In a 10-year retrospective study, we evaluated the clinicopathologic features and renal immunofluorescence patterns of glomerulonephritis in 41 dogs. On the basis of results of histologic examinations, the dogs were segregated into 3 groups, including membranous (n = 12), mesangioproliferative (n = 15), or membranoproliferative glomerulonephritis (n = 14). No significant differences existed among groups in regard to age or duration of illness. Most dogs had been ill for one month or longer. The proportion of dogs with azotemia, anemia, and hyperphosphatemia were not different among the disease groups. Proportion of dogs with hypoalbuminemia and the severity of hypoalbuminemia were not different among groups. Highest urine protein losses and 24-hour urine protein/creatinine ratios developed in dogs with membranous glomerulonephritis. Although hypoalbuminemia and hypercholesterolemia were common (49%), the formation of edema or ascites was not (15%) and, therefore, few dogs had all of the classic features of the nephrotic syndrome. Few dogs suffered thromboembolic complications. Antinuclear antibody titers developed in 11 dogs, the highest titers developing in dogs with polyarthritis and systemic lupus erythematosis. Cellulose acetate electrophoresis detected alpha 2 and beta 1 globulin spikes in most dogs (87%). Results of renal immunofluorescence testing were positive in 36 dogs, using polyvalent antisera for immunoglobulins (Ig)G, IgA, IgM, and/or antisera for complement factor C3. When monovalent antisera for IgG, IgA, and IgM, and fibrinogen were used, immunofluorescence was not observed as often. The major fluorescent pattern was discrete multifocal segmental granular glomerular fluorescence, consistent with immune-complex deposition. Two dogs had linear glomerular staining patterns; however, antibodies directed against normal glomerular basement membrane were not found via elution studies. A high prevalence of glucocorticoid excess (treatment with glucocorticoids and spontaneous hyperadrenocorticism) (34%), chronic inflammatory skin disease (27%), neoplasia (17%), polyarthritis (12%), and systemic lupus erythematosis (7%) were observed as clinical problems concurrent with glomerulonephritis. In 5 dogs, treatment of glomerulonephritis with prednisolone (0.5 to 1.1 mg/kg) did not result in beneficial effects and in fact appeared to be detrimental, leading to azotemia and worsening proteinuria and physical condition in some of the dogs.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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Fifty Suffolk-crossbred wether lambs, with an initial live weight of 29 +/- 2.1 kg, were allocated to one of five concentrate-based diets formulated to have a similar fatty acid content (60 g/kg DM), but containing either linseed oil (high in 18:3n-3); fish oil (high in 20:5n-3 and 22:6n-3); protected linseed and soybean (PLS; high in 18:2n-6 and 18:3n-3); fish oil and marine algae (fish/algae; high in 20:5n-3 and 22:6n-3); or PLS and algae (PLS/algae; high in 18:3n-3 and 22:6n-3). Lambs were slaughtered when they reached 40 kg. Growth performance and intake were similar (P > 0.35) among treatments. By contrast, gain:feed was higher (P < 0.05) in lambs fed the fish oil compared with the linseed oil or PLS/algae diets. Total fatty acid concentration (mg/100 g) in the neutral lipid of the longissimus muscle was not affected by treatment (P > 0.87) but was least (P < 0.05) in the phospholipid fraction in lambs fed the linseed oil diet. Lambs fed either diet containing marine algae contained the highest (P < 0.05) percentage of 22:6n-3 in the phospholipid (mean of 5.2%), 2.8-fold higher than in sheep fed the fish oil diet. In lambs fed the fish/algae diet, the percentage of 20:5n-3 was highest (P < 0.05), contributing some 8.7, 0.8, and 0.5% of the total fatty acids in the muscle phospholipid, neutral lipids, and adipose tissue, respectively. The percentage of 18:3n-3 in the phospholipid fraction of the LM was highest (P < 0.05) in lambs fed the linseed oil diet (6.9%), a value double that of sheep fed the PLS diet. By contrast, lambs fed the PLS diet had twice the percentage of 18:3n-3 in the muscle neutral lipids (3.8%) than those offered the linseed oil diet, and 5.5-fold greater than lambs fed the fish/algae treatment (P < 0.05), an effect that was similar in the adipose tissue. The percentage of 18:2n-6 was highest (P < 0.05) in lambs fed the PLS diet, where it contributed 33.7, 10.1, and 11.2% in the muscle phospholipid, neutral lipids, and adipose tissue, respectively. The highest (P < 0.05) muscle PUFA-to-saturated fatty acid (P:S) ratio was obtained in lambs fed the PLS diet (0.57), followed by the PLS/algae diet (0.46), and those fed the fish oil or linseed oil diets had the lowest ratios (0.19 and 0.26, respectively). The favorable P:S ratio of lambs fed the PLS/algae diet, in conjunction with the increased levels of 20:5n-3 and 22:6n-3, enhanced the nutritional qualities of lamb to more closely resemble what is recommended for the human diet.  相似文献   
45.
The feline odontoclastic resorptive lesion (FORL) status (presence or absence of odontoclastic resorptive lesions) of 423 clinically healthy cats was determined based on radiographic findings in a series of full mouth radiographs (eight views). This status was compared with the FORL status based on evaluation of only two views, namely the right and left mandibular premolar and molar views. Using the FORL status of the right and left third mandibular premolars (307 and 407) alone correctly predicted overall FORL status in 93.4 per cent of cats. The sensitivity of the new technique (FORL cases correctly diagnosed as positive by the test) was 78.5 per cent, while the negative predictive value (negative FORL cases correctly diagnosed by the test) was 91.3 per cent. Overall FORL status can therefore be confidently diagnosed in nine out of 10 cats by assessing FORL status in just two teeth (307 and 407) using two films, which has benefits for the cat (less anaesthetic time and reduced exposure to radiation) and the owner (reduced cost of screening).  相似文献   
46.
The diet of 745 Oreochromis mossambicus (Peters) of less than 0,5 up to 2000 g wet mass, in Hartbeespoort Dam, was determined from stomach content analysis. Samples of fish were selected to cover a whole annual cycle. Small fish fed initially on zoobenthos and zooplankton, but fish with a mass of over 4 g fed increasingly on Microcystis aeruginosa Kutzing and detritus until these food items formed the dominant food source in O. mossambicus over 8 g. Some cannibalism was encountered in fish up to 64 g in the summer months. The ratio of intestinal length to total length of fish ranged from 0,58 in the smaller fish to 11,02 in larger fish and this indicated that there was an ontogenetic adaptation from a carnivorous to a phytoplanktivorous/detritivorous diet. Feeding in juvenile fish studied over 24 h was found to be most intense in the early morning and late afternoon but remained high throughout daylight hours decreasing considerably at night. The daily ingestion rate of food in O. mossambicus in Hartbeespoort Dam was estimated at 453 mg/g of fish. This comprised 45% M. aeruginosa and 55% detritus. It was apparent that of this matter ingested only a small percentage would be assimilated. Oreochromis mossambicus shows feeding and breeding preadaptations which enable it to successfully exploit a lacustrine environment. These adaptations enable it to maintain a large population in Hartbeespoort Dam despite frequent winter mortalities caused by water temperatures below their tolerance limits.  相似文献   
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Chronic enteropathy (CE) in dogs is common worldwide, but little data is available from Australia. The aim of this study was to describe treatment response and long‐term outcome in a cohort of dogs with CE. Dogs were prospectively enrolled at Murdoch University and the University of Melbourne. After diagnostic investigation to rule out diseases other than CE, dogs underwent sequential therapeutic trials until achieving a clinical response (diet then antibiotics, and finally immunosuppressants). Success was defined as 75% reduction of clinical severity for a minimum of five weeks. A total of 21 dogs were enrolled, and 19 completed the study. One dog was euthanised for lack of response to treatment and one excluded for lack of owner compliance. Most dogs responded to diet (n = 10), followed by antibiotics (n = 7) and immunosuppressants (n = 2). Long‐term remission (median 21.1 months, [3.0‐44.7]) was achieved in eight out of ten dietary responders without additional treatment. In contrast, only two dogs with antibiotic response remained in long‐term remission, of which one needed on‐going antibiotic treatment. Longer term remission was achieved in the two dogs treated with immunosuppressants with on‐going low dose therapy. This study concludes that most dogs referred for CE in Australia respond to dietary treatment (even after previous dietary interventions), and remission is long‐term compared to dogs treated with an antibiotic. Furthermore, the need for long‐term antibiotics in some dogs to maintain response may lead to antibiotic resistance. This study supports adequate dietary trials for CE in dogs, and a need for alternative second‐line treatments.  相似文献   
49.
Bovine tuberculosis (TB) is an important economic problem. The incidence of TB in cattle herds has steadily risen in the UK, and badgers are strongly implicated in spreading disease. Since the mid-1970s the UK government has adopted a number of badger culling strategies to attempt to reduce infection in cattle. In this report, an established model has been used to simulate TB in badgers, transmission to cattle, and control by badger culling. Costs were supplied by the UK Government's Department for Environment Food and Rural Affairs (Defra) for badger trapping and gassing. Regardless of culling intensity or area simulated, an overall reduction in the herd breakdown rate was seen. With a high culling efficacy and no social perturbation, the mean Net Present Value of a few simulated culling strategies in an "ideal world" was positive, meaning the economic benefits outweighed the costs. Further work is required before these results could be considered definitive, as it is necessary to evaluate uncertainties and simulate less than perfect conditions.  相似文献   
50.
A partial skeleton of a primitive bird, Rahona ostromi, gen. et sp. nov., has been discovered from the Late Cretaceous of Madagascar. This specimen, although exhibiting avian features such as a reversed hallux and ulnar papillae, retains characteristics that indicate a theropod ancestry, including a pubic foot and hyposphene-hypantra vertebral articulations. Rahona has a robust, hyperextendible second digit on the hind foot that terminates in a sicklelike claw, a unique characteristic of the theropod groups Troodontidae and Dromaeosauridae. A phylogenetic analysis places Rahona with Archaeopteryx, making Rahona one of the most primitive birds yet discovered.  相似文献   
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