Splenic Infarction in 16 Dogs: A Retrospective Study

Sixteen dogs with splenic infarction due to causes other than splenic torsion were identified. Dogs with splenic infarction often had multiple concurrent diseases, and surgical management of splenic infarction was associated with high mortality. Splenic infarction occurred in dogs with hypercoagulable conditions associated with liver disease, renal disease, and hyperadrenocorticism, or as a consequence of uniform splenomegaly, neoplasia, or thrombosis associated with cardiovascular disease. Clinical signs and common laboratory findings generally reflected the underlying disease process. A variety of splenic abnormalities were detected by abdominal ultrasound in 15 dogs, with the ventral extremity of the spleen being most often abnormal. Four dogs were euthanized or died because of the presence of severe systemic disease, whereas 12 dogs underwent laparotomy. Complete splenectomy was performed in 9 dogs and partial splenectomy was performed in 2 dogs. Seven dogs died in the immediate postoperative period, 3 required chronic veterinary care, and 2 had uncomplicated long-term recoveries. Splenic infarction should be regarded as a sign of altered blood flow and coagulation, rather than as a primary disease, and surgical management should be reserved for patients with life-threatening complications such as hemoabdomen or sepsis.     

Incidence of and risk factors for adverse events associated with distemper and rabies vaccine administration in ferrets

OBJECTIVE: To determine incidence of and risk factors for adverse events associated with distemper and rabies vaccine administration in ferrets. DESIGN: Retrospective cohort study. ANIMALS: 3,587 ferrets that received a rabies or distemper vaccine between January 1, 2002, and December 31, 2003. PROCEDURES: Electronic medical records were searched for possible vaccine-associated adverse events. Adverse events were classified by attending veterinarians as nonspecific vaccine reactions, allergic reactions, or anaphylaxis. Patient information that was collected included age, weight, sex, cumulative number of distemper and rabies vaccinations received, clinical signs, and treatment. The association between potential risk factors and occurrence of an adverse event was estimated with logistic regression. RESULTS: 30 adverse events were recorded. The adverse event incidence rates for administration of rabies vaccine alone, distemper vaccine alone, and rabies and distemper vaccines together were 0.51%, 1.00%, and 0.85%, respectively. These rates were not significantly different. All adverse events occurred immediately following vaccine administration and most commonly consisted of vomiting and diarrhea (52%) or vomiting alone (31%). Age, sex, and body weight were not significantly associated with occurrence of adverse events, but adverse event incidence rate increased as the cumulative number of distemper or rabies vaccinations received increased. In multivariate logistic regression analysis, only the cumulative number of distemper vaccinations received was significantly associated with the occurrence of an adverse event. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that in ferrets, the risk of vaccine-associated adverse events was primarily associated with an increase in the number of distemper vaccinations.     

Vaccination with recombinant NetB toxin partially protects broiler chickens from necrotic enteritis

NetB toxin from Clostridium perfringens is a major virulence factor in necrotic enteritis in poultry. In this study the efficacy of NetB as a vaccine antigen to protect chickens from necrotic enteritis was examined. Broiler chickens were immunized subcutaneously with purified recombinant NetB (rNetB), formalin treated bacterin and cell free toxoid with or without rNetB supplementation. Intestinal lesion scores and NetB antibody levels were measured to determine protection after mild oral gavage, moderate in-feed and heavy in-feed challenges with virulent C. perfringens isolates. Birds immunized with rNetB were significantly protected against necrotic enteritis when challenged with a mild oral dose of virulent bacteria, but were not protected when a more robust challenge was used. Bacterin and cell free toxoid without rNetB supplementation did not protect birds from moderate and severe in-feed challenge. Only birds immunized with bacterin and cell free toxoid supplemented with rNetB showed significant protection against moderate and severe in-feed challenge, with the later giving the greatest protection. Higher NetB antibody titres were observed in birds immunized with rNetB compared to those vaccinated with bacterin or toxoid, suggesting that the in vitro levels of NetB produced by virulent C. perfringens isolates are too low to induce the development of a strong immune response. These results suggest that vaccination with NetB alone may not be sufficient to protect birds from necrotic enteritis in the field, but that in combination with other cellular or cell-free antigens it can significantly protect chickens from disease.     

Assessing the relationship between patch type and soil mites: A molecular approach

An urgent need exists for indicators of soil health and patch functionality in extensive rangelands that can be measured efficiently and at low cost. Soil mites are candidate indicators, but their identification and handling is so specialised and time-consuming that their inclusion in routine monitoring is unlikely. The aim of this study was to measure the relationship between patch type and mite assemblages using a conventional approach. An additional aim was to determine if a molecular approach traditionally used for soil microbes could be adapted for soil mites to overcome some of the bottlenecks associated with soil fauna diversity assessment. Soil mite species abundance and diversity were measured using conventional ecological methods in soil from patches with perennial grass and litter cover (PGL), and compared to soil from bare patches with annual grasses and/or litter cover (BAL). Soil mite assemblages were also assessed using a molecular method called terminal-restriction fragment length polymorphism (T-RFLP) analysis. The conventional data showed a relationship between patch type and mite assemblage. The Prostigmata and Oribatida were well represented in the PGL sites, particularly the Aphelacaridae (Oribatida). For T-RFLP analysis, the mite community was represented by a series of DNA fragment lengths that reflected mite sequence diversity. The T-RFLP data showed a distinct difference in the mite assemblage between the patch types. Where possible, T-RFLP peaks were matched to mite families using a reference 18S rDNA database, and the Aphelacaridae prevalent in the conventional samples at PGL sites were identified, as were prostigmatids and oribatids. We identified limits to the T-RFLP approach and this included an inability to distinguish some species whose DNA sequences were similar. Despite these limitations, the data still showed a clear difference between sites, and the molecular taxonomic inferences also compared well with the conventional ecological data. The results from this study indicated that the T-RFLP approach was effective in measuring mite assemblages in this system. The power of this technique lies in the fact that species diversity and abundance data can be obtained quickly because of the time taken to process hundreds of samples, from soil DNA extraction to data output on the gene analyser, can be as little as 4 days.     

Soil quality and financial performance of biodynamic and conventional farms in new zealand

Biodynamic farming practices and systems show promise in mitigating some of the detrimental effects of chemical-dependent, conventional agriculture on the environment. The physical, biological, and chemical soil properties and economic profitability of adjacent, commercial biodynamic and conventional farms (16 total) in New Zealand were compared. The biodynamic farms in the study had better soil quality than the neighboring conventional farms and were just as financially viable on a per hectare basis.     

Use of enzyme-linked immunosorbent assay to detect potato leafroll virus in field grown potato,cv. Russet Burbank

Use of enzyme-linked immunosorbent assay (ELISA) in detecting potato leafroll infections in field grown potato, cv. Russet Burbank, was studied from 1986 to 1988 at Rosemount, Minnesota. The objective was to determine relative reliability of current season foliage ELISA, tuber tissue ELISA, and tuber progeny foliage ELISA. Serological tests were most accurate when foliage of tuber progenies was tested. ELISA underestimated total leafroll infection when current season foliage from the inoculated plant was used, in those plants inoculated during late tuber bulking stage. Current season foliage ELISA tests using newly expanded terminal leaflets were more reliable than were tests using older leaflets. Leafroll infection was detected in the current season foliage and tuber progenies (tuber tissue as well as tuber progeny foliage) of some plants seven days after inoculation. Most current season foliage infections were detected by day 14–28 depending on year. Differences among years were most likely caused by variation in quality of virus source plants and numbers of vectors used in inoculation. ELISA tests on tuber tissue were almost as effective as ELISA tests on tuber progeny foliage in detecting potato leafroll 20 days after inoculation, but ELISA on tuber tissue substantially underestimated infection if plants were sampled earlier. Maximum percent tuber infection occurred 20 days or more after inoculation. Movement of the virus from the inoculated stem to other stems decreased with increased plant age at inoculation. Percent infected tubers declined with increased plant age at inoculation. Action thresholds developed for aphids in managing potato leafroll virus should take into account the temporal change in percent infected tubers.     

Characterization of the trade in manta and devil ray gill plates in China and South‐east Asia through trader surveys

相似文献   

The role of technology in enhancing low resource agriculture in Africa

Traditional forms of farming, herding, and fishing are remarkably adapted to African conditions but these traditional approaches are being overtaken by modern pressures, particularly population growth. According to a report published by the Office of Technology Assessment (OTA), a nonpartisan analytical support agency of the U. S. Congress, one promising way to help African farmers and herders would be for development assistance organizations to focus more attention on the various forms of low-resource agriculture that predominate in Africa. In keeping with OTA's mission and primary audience, “Enhancing Agriculture in Africa: A Role for U. S. Development Assistance” (1988) is a policy-oriented synthesis of available technical information. The report provides Congress with a range of options that, if pursued, could help Africans enhance agriculture, increase their food security, and improve their lives. This paper is drawn from the larger OTA report, and it focuses on the role technology might play in enhancing low-resource agriculture. Readers should see the full assessment (OTA, 1988) for more information on policy considerations; the specific technologies mentioned; or a complete list of advisory panel members, workshops and participants, and commissioned papers. OTA's report comes at a critical time: for a variety of reasons—ranging from changing values to increased budget constraints—U. S. foreign assistance policy is undergoing a fundamental reevaluation. This review of the potential of low-resource agriculture, and options the United States might pursue to enhance this approach, was intended to aid in this reevaluation.