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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   
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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   
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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   
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This project was developed to gather data on the general moral reasoning of practicing veterinarians and to compare the responses of small animal veterinarians vs large animal veterinarians and of male veterinarians vs female veterinarians. Using the Defining Issues Test for assessing moral reasoning, it was found that there is no significant difference between the levels of moral reasoning of small animal and large animal veterinarians. However, a slightly significant (P = 0.045) difference was found between the levels of moral reasoning of male and female veterinarians. Explanations of these findings are given. This report provides baseline data on the moral reasoning of veterinarians, which can serve as a foundation and stimulus for comparison in other studies.  相似文献   
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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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The successful development of phenology models from field studies depends on many factors, some of which are entirely under the control of pest managers. For example, one such factor is the choice of method for calculating thermal units. In this study, we have demonstrated that four methods for calculating thermal units provided for acceptable predictions of one phenological event of one insect species, while another method for calculating thermal units did not. The measure of central tendency (mean or median) that is used to estimate lower developmental temperatures and required thermal summations is another factor that pest managers can control when developing phenology models from field studies. Here, we show that predictions that were made when using phenology models based on median lower developmental temperatures and median required thermal summations were superior to predictions that were made when using phenology models based on mean lower developmental temperatures and mean required thermal summations. The use of bootstrap vs. non-bootstrap estimates of lower developmental temperatures and required thermal summations is yet another factor that pest managers can control when developing phenology models from field studies. In this study, we found that calculating and using bootstrap estimates of lower developmental temperatures and required thermal summations in phenology models did not improve the predictions of one phenological event for one insect species. The implications of these and other findings are discussed.  相似文献   
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Live weight loss (shrink) and liver conditions (abscesses) were determined on 3,570 crossbred steers of predominantly British breeding over a 5-yr period. Starting in November 1979, steers were placed on feed at bimonthly intervals and provided one of three housing treatments: no shelter, access to overhead shelter or confinement. All steers were implanted with Synovex during the first 3 yr and Compudose the last 2 yr and fed a diet consisting of high-moisture corn grain, which provided 85% of the energy, and corn silage, along with a protein, vitamin and mineral supplement. Cattle were processed into beef after a feeding period of approximately 160 d. Year affected shrink (P less than .001), and month on feed and housing type tended to alter shrink. Cattle marketed during summer and fall and those outside without overhead shelter tended to shrink more. Year, month on feed and housing type affected liver condition (P less than .01). Cattle started on feed in November and January and cattle housed in confinement or outside without overhead shelter had higher incidences of liver abscesses and slower average daily gains (P less than .01). Daily gains for steers with normal and abnormal livers were not different (P greater than .19) for any month started on feed or housing treatment. These results indicate that under the conditions of this study a 2 or 3% weight loss should be expected during the marketing of finished steers and a 16% incidence of liver abscesses should be anticipated, with some modification of the latter due to time of year and housing. The presence of liver abscesses at the time of processing steers into beef did not reduce feedlot performance.  相似文献   
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