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51.
A 6-year-old, male neutered mixed breed dog was presented emergently with a three-week history of hyporexia, vomiting, diarrhoea and weight loss. Upon examination, the patient was dull, had generalised muscle atrophy, moderate abdominal pain and a mild amount of peritoneal effusion. A fluid-filled, distended, corrugated small bowel with marked gastroparesis and moderate peritoneal effusion was noted on abdominal ultrasonography. Endoscopy revealed hyperaemic and friable mucosa and a subjectively narrowed pylorus. Emergency exploratory celiotomy was performed due to worsening patient condition and revealed thick, diffuse, fibrous adhesions of the abdominal cavity. Based on these findings, sclerosing encapsulating peritonitis (SEP) was suspected. A large mass of omentum adjacent to the greater curvature of the stomach had caused a pyloric outflow obstruction. Adhesiolysis was attempted but was unsuccessful due to the friability of the small intestines. The dog was humanely euthanased under anaesthesia. A diagnosis of SEP was confirmed via necropsy. No underlying cause was identified. This is the first known case of a pyloric outflow obstruction secondary to SEP in a dog. Although rare, this condition should be considered as a differential for dogs with signs of a pyloric outflow obstruction with concurrent ascites and abdominal pain, hyporexia, vomiting and diarrhoea.  相似文献   
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We investigated the effects of herbaceous and woody vegetation control on the survival and growth of planted eastern white pine (Pinus strobus L.) seedlings through six growing seasons. Herbaceous vegetation control involved the suppression of grasses, forbs, ferns, and low-shrubs, and was maintained for 0, 2, or 4 years after white pine seedlings were planted. Woody control involved the removal of all tall-shrub and deciduous trees, and was conducted at the time of planting, at the end of the second or fifth growing seasons, or not at all. Seedling height and basal diameter responded positively and proportionally to duration of herbaceous vegetation control. Gains associated with woody control were generally not significant unless some degree of herbaceous vegetation control was also conducted. Only herbaceous control increased pine crown closure and rate of crown closure. Herbaceous control and the presence of 5000–15,000 stems per ha of young overtopping aspen were associated with reduced weevil (Pissodes strobi Peck.) injury and increased pine height growth. The study suggests that white pine restoration strategies on clearcut sites should focus on the proactive, early management of understory vegetation and the gradual reduction of overtopping cover from woody vegetation to create a seedling light environment that supports acceptable growth with minimal weevil damage.  相似文献   
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Non-esterified fatty acid (NEFA) levels in housed, 3-month-old calves were monitored in two experiments designed to establish (i) the effect of diet and time of sampling in relation to feeding on blood levels; and (ii) the relationship between appetite and plasma NEFA in animals on chopped hay. In the first experiment, a significant drop in NEFA levels was recorded after feeding. Furthermore, the NEFA levels of calves maintained on concentrate were significantly lower than those on hay throughout the post-feeding period. In the second study, a significant negative correlation was established between NEFA levels and intake of chopped hay in (i) ad-lib-fed calves infected with the abomasal nematode Ostertagia ostertagi; (ii) worm-free animals pair-fed with those in group (i); and (iii) ad-lib-fed worm-free calves. Regression analysis of raw and transformed data from all three groups combined also yielded significant correlations. It is suggested that the measurement of blood NEFA may be a useful indirect indicator of feed intake in conditioned housed calves offered hay diets.  相似文献   
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OBJECTIVE: To develop an aerosol exposure method for induction of brucellosis in rhesus macaques (Macaca mulatta). ANIMALS: 10 adult rhesus macaques. PROCEDURE: 8 rhesus macaques were challenge exposed with 10(2) to 10(5) colony-forming units of Brucella melitensis 16M by use of an aerosol-exposure technique, and 2 served as control animals. All macaques were euthanatized 63 days after challenge exposure. Gross and microscopic lesions, bacterial burden in target organs, and histologic changes in tissues were evaluated. RESULTS: Grossly, spleen weights were increased in exposed macaques, compared with spleen weights in control macaques. Histologically, there was inflammation in the liver, kidneys, spleen, testes, and epididymides in exposed macaques. The spleen and lymph nodes had increased numbers of lymphohistiocytic cells. Morphometrically, the spleen also had an increased ratio of white pulp to red pulp. Areas of hepatitis and amount of splenic white pulp increased with increasing exposure dose. CONCLUSIONS AND CLINICAL RELEVANCE: Pathologic findings in rhesus macaques after aerosol exposure to B melitensis are similar to those observed in humans with brucellosis. IMPACT FOR HUMAN MEDICINE: These results may aid in the development of a vaccine against brucellosis that can be used in humans.  相似文献   
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OBJECTIVE: To estimate the specificity of an absorbed enzyme-linked immunosorbent assay kit for Johne's disease (JD) when used in mature cattle populations resident in northern Australia. DESIGN: Blood samples were collected from beef cattle in northern Queensland, the Northern Territory and northern Western Australia, and from dairy cattle in northern Queensland. The specificity of a serological test for JD was estimated by testing the blood samples with an absorbed ELISA kit. Further samples were collected from cattle with positive ELISA results to determine the presence or absence of infection with Mycobacterium avium subsp paratuberculosis. PROCEDURE: During 1995 and 1996, blood, tissue and gut contents were collected from beef cattle at abattoirs in Queensland and the Northern Territory; and blood and faecal samples were collected from dairy cattle in herds assessed to be most at risk for JD in northern Queensland. The blood samples were tested using an absorbed ELISA kit. Tissues and gut contents from beef cattle that had positive ELISA results were cultured for M. avium subsp paratuberculosis, and tissues were examined histologically. Faecal samples from dairy cattle with positive ELISA results were cultured for M. avium subsp paratuberculosis. RESULTS: Estimates of specificity for this absorbed ELISA in mature northern Australian cattle were 98.0% (97.0 to 98.8%, 95% CI) in beef cattle, and 98.3% (96.7 to 99.3%, 95% CI) in dairy cattle. CONCLUSION: Estimates of specificity in this study were lower for beef cattle from the Northern Territory and northern Western Australia and for dairy cattle from northern Queensland than those quoted from studies on cattle in southern Western Australia. This should be considered when serological testing using the JD ELISA is carried out on northern Australian cattle.  相似文献   
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The brown tree snake (Boiga irregularis) is invasive in Guam and presents a continuous threat of accidental export to new islands in outbound cargo. Current attempts to avoid that scenario rely primarily on canine teams to inspect outbound cargo and vehicles. In prior work, we showed that thermal fumigation could effectively elicit snake exit of cargo under conditions when free flow of air streams is feasible, but this method cannot work with tightly packed cargo. Here we show radiative heating can effectively induce snake exit from cargo refuges at temperatures of 44–48 °C; however, we find passive solar heating of cargo to be unreliable in attaining sufficiently high temperatures for cargo sterilization. Although passive solar radiant heating proved unreliable, an active radiant-heating system has promise as a reliable means of treating tightly packed cargo. Times needed for treatment in a closed, controlled setting are sufficiently short that routine application of the method should provide no serious interruption of normal cargo-handling procedures.  相似文献   
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