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1.
SUMMARY The proposal by the Zoological Parks Board of New South Wales to import 10 southern black rhinoceros (Diceros bicornis) from Zimbabwe as part of an international project for conservation of the species presented the Australian Quarantine and Inspection Service (AQIS) with a unique challenge. This importation is, at least in the modern era, the first importation of live herbivores from the African continent. Many of the serious animal diseases in the world are endemic in parts of Africa. Knowledge of which of these diseases infect wild species and may be transmitted from the wild species to domesticated species, is limited. This paper describes the strategies adopted by AQIS to facilitate the importation of rhinoceros while maintaining protection of Australian consumers, rural industries, domestic livestock and fauna against the entry and spread of unwanted pests and diseases.  相似文献   
2.
The original article to which this Correction refers was published in Pest Management Science 58 (7): 649–662 (2002).Copyright © 2004 Society of Chemical Industry  相似文献   
3.
Streptococcus iniae has become one the most serious aquatic pathogens in the last decade causing high losses in farmed marine and freshwater finfish in warmer regions. Although first identified in 1976 from a captive Amazon freshwater dolphin, from which it derives its name, disease outbreaks had most likely been occurring for several decades in marine aquaculture in Japan. S. iniae is globally distributed throughout warm water finfish aquaculture. In common with other encapsulated beta-haemolytic streptococci and in direct contradiction to the phenomenal success story of bacterial vaccines in finfish aquaculture, control of S. iniae by vaccination has met with limited success. Thus, antibiotic usage is the current practice for reducing mortality and consequent economic loss. Vaccine failure appears to result in part from serotypic variation and, whilst 2 serotypes have been named, variation would appear to be more complex. S. iniae also has zoonotic potential, with human infections identified in the USA, Canada, and throughout Asia. In humans, infection is clearly opportunistic with all cases to date associated with direct infection of puncture wounds during preparation of contaminated fish, and generally in elderly or immunocompromised individuals. Significant progress has been made in terms of research into pathogenic mechanisms of S. iniae, with recent research elucidating the role of capsule in virulence for fish through antiopsonic activity. In light of this recent coverage in the literature, the present review centres on areas of direct veterinary interest including identification, epidemiology, therapy and prevention in farmed finfish. Clearly as the prevalence of S. iniae and associated economic losses continue to increase, further work towards developing a reliable vaccine is essential. This would appear to require a much better understanding of cell-surface variability amongst S. iniae isolates.  相似文献   
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5.
Diagnosis of avian mycobacteriosis, caused by Mycobacterium genavense or species belonging to the Mycobacterium avium complex (MAC), is problematic. Polymerase chain reaction (PCR) offers rapid and sensitive detection of minute quantities of DNA, and conventional protocols have been used for evaluating avian specimens. The recent development of real-time PCR offers several advantages over conventional PCR. In attempts to improve diagnosing avian mycobacteriosis, a real-time TaqMan PCR assay was developed targeting the 65-kD heat shock protein gene of M. genavense and MAC spp. Nineteen reference isolates, 16 clinical isolates, and 32 avian tissue samples were used to evaluate the assay. When sufficient amplicons were produced, the species of mycobacteria was determined by standard sequencing of TaqMan PCR products and compared with results from commercial mycobacteriology laboratories and/or standard sequencing of conventional PCR products. The TaqMan PCR detected DNA from reference isolates of M. genavense, MAC spp., and Mycobacterium tuberculosis complex spp. Of the clinical isolates, the TaqMan PCR detected DNA from 10 of 12 Mycobacterium avium avium isolates and two of three Mycobacterium avium intracellulare isolates. For the tissue samples, the TaqMan PCR amplified DNA in six of nine samples that were identified by sequencing of conventional PCR products and/or by commercial mycobacteriology laboratories as being MAC spp. positive and three of four samples that were positive for M. genavense. There was some disagreement between speciation results from the TaqMan PCR and those from commercial mycobacteriology laboratories or conventional PCR or both. This disagreement was suspected to be because of relatively small numbers of base pairs in the TaqMan PCR products. The TaqMan PCR may provide a useful tool for evaluating clinical samples for DNA from mycobacteria species that most commonly infect birds; however, further refinement is needed in order to improve sensitivity and provide more accurate speciation.  相似文献   
6.
OBJECTIVE: To describe the ultrasonographic and quantitative histologic effect of injecting 2% iodine in almond oil (IAO) and ethanolamine oleate (EO) in the medial and middle patellar ligaments of horses and to determine whether a difference in response exists between IAO and EO treatment. ANIMALS: 10 healthy horses. PROCEDURE: In 5 horses, the medial and middle patellar ligaments of 1 limb were injected with EO, whereas IAO was injected in the medial and middle patellar ligaments of another 5 horses. Ultrasonographic evaluation was performed on the experimental and control limb before injection of IAO and EO and prior to euthanasia to determine cross-sectional area and evaluate fiber pattern. The patellar ligaments were harvested 2 weeks after injection and examined histologically to evaluate the inflammatory response, fibroplasia, and chondroid metaplasia. RESULTS: Injection of the patellar ligaments with IAO resulted in a greater increase in cross-sectional area on ultrasonography than EO. Both agents caused a decrease in echogenicity of the ligament. Histologically, significantly greater infiltration of inflammatory cells and fibroplasia developed after injection with IAO, compared with EO. Both agents resulted in significantly greater fibroplasia relative to control specimens. CONCLUSIONS AND CLINICAL RELEVANCE: Injection of the medial and middle patellar ligaments with IAO induces more severe inflammation and fibroplasia than EO. Maturation of the inflammatory and fibrous response may contribute to resolution or attenuation of upward fixation of the patella by subsequent stiffening of the ligaments.  相似文献   
7.
An adult male black-necked swan (Cygnus melanocoryphus) was evaluated for a routine physical examination and West Nile virus vaccination. Nine days later, the swan was hospitalized for weakness, dehydration, tremors, and leukocytosis. Gradual clinical improvement was seen over a 2-wk course of supportive care. However, the animal became acutely weak and was found dead. Histopathology revealed severe granulomatous pneumonia and air sacculitis with dissemination to the liver, spleen, intestine, and coelom. Mycobacterial infection was confirmed by identification of acid-fast bacilli within tissue sections and by polymerase chain reaction. Concurrent West Nile virus infection was identified in sections of brain by using immunohistochemistry.  相似文献   
8.
Objective The aims of this work were to (1) develop a low-cost equine movement tracking collar based on readily available components, (2) conduct preliminary studies assessing the effects of both paddock size and internal fence design on the movements of domestic horses, with and without foals at foot, and (3) describe distances moved by mares and their foals. Additional monitoring of free-ranging feral horses was conducted to allow preliminary comparisons with the movement of confined domestic horses. Procedures A lightweight global positioning system (GPS) data logger modified from a personal/vehicle tracker and mounted on a collar was used to monitor the movement of domestic horses in a range of paddock sizes and internal fence designs for 6.5-day periods. Results In the paddocks used (0.8–16 ha), groups of domestic horses exhibited a logarithmic response in mean daily distance travelled as a function of increasing paddock size, tending asymptotically towards approximately 7.5 km/day. The distance moved by newborn foals was similar to their dams, with total distance travelled also dependent on paddock size. Without altering available paddock area, paddock design, with the exception of a spiral design, did not significantly affect mean daily distance travelled. Feral horses (17.9 km/day) travelled substantially greater mean daily distances than domestic horses (7.2 km/day in 16-ha paddock), even when allowing for larger paddock size. Conclusions Horses kept in stables or small yards and paddocks are quite sedentary in comparison with their feral relatives. For a given paddock area, most designs did not significantly affect mean daily distance travelled.  相似文献   
9.
Data from 286 beef cattle, obtained in total diet digestibility assessments, were used to examine effects of dietary and animal factors on N excretion in feces and urine and to develop prediction equations for N excretion in beef cattle. The animals used were mainly from beef breeds, at various ages (from growth to finishing) and live BW (153 to 580 kg), and offered diets containing grass silage at production feeding levels. Dietary forage proportion ranged from 199 to 1,000 g/kg of DM and dietary CP concentration from 108 to 217 g/kg of DM. Linear and multiple regression techniques were used to examine relationships between the efficiency of N utilization and dietary and animal variables with the experimental effects removed. The statistical analysis indicated that N excretion was related positively (P < 0.001) to live BW and intakes of DM, N, and ME, and negatively (P < 0.001) to dietary forage proportion. The prediction equation for N excretion, developed using N intake alone, produced a large r2 (0.898) and a small SE (12.3). Addition of live BW and forage proportion as supporting predictors to this relationship only marginally increased R2 to 0.915 and reduced SE to 11.2. Nitrogen excretion was less well related to live BW (r2 = 0.771, SE = 18.5) than to N intake. Addition of N intake as a proportion of DMI or ME intake to the relationship between live BW and N excretion increased R2 to 0.824 and reduced SE to 16.2. The internal validation of these equations revealed that using N intake as the primary predictor produced a very accurate prediction of N excretion. In situations where data on N intake are not available, prediction equations based on live BW and dietary N concentration together can produce a relatively accurate assessment of N excretion. A number of mitigation strategies to reduce N excretion in feces and urine in beef cattle are discussed, including manipulation of dietary N concentration, diet quality, and level of feeding. The prediction equations and mitigation strategies developed in the current study provide an approach for beef producers to quantify N excretion against production and to develop their own mitigation strategies to reduce N excretion.  相似文献   
10.
J. D. Agnew 《Plant Breeding》1986,97(2):183-186
Self-pollination of 2f species of vandaceous orchids was followed by later embryo culture carried out to determine which species are self-compatible (SC) or incompatible (SI): 10 are SC, 1 are SI and the remaining:8 require further study. In the SI species, a few progeny could usually be recovered and these are interpreted as arising from mutation at the incompatibility locus (loci). The implications of the findings for current models of incompatibility are discussed.  相似文献   
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