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1.
Service dogs are an essential aid to persons with disabilities, providing independence, mobility, and improved self-esteem. Because of these proven benefits, the growing use of service dogs is creating a demand and supply crisis. One major cause is the 50% average dropout rate for dogs selected for training. Weiss and Greenber (1997) recently found that a dog, successful on the most commonly used selection test items, was as likely to be either a poor or a good candidate for service work. The experiment presented here evaluated test items developed by the author in 15 years of experience with dogs. The test items were administered to 75 dogs from the Kansas Humane Society. Once tested, the dogs received obedience and retrieval training. The experiment assessed each dog on behavior over 5 weeks of training versus performance on each selection test item. A subset of the selection items, combined in a regression analysis, accounted for 36.4% of the variance with R = 0.603. This research also revealed a reliable test for dog aggression without risking injury to dog or tester. Items for testing included fear, motivation, and submission. Another set of selection items reliably predicted the trait of “high energy ”commonly described as “high strung. ”Future research should involve investigating the effectiveness of both cortisol levels and blood pressure in predicting traits to help strengthen the predictive value of the tool and then testing on dogs trained to be full service dogs.  相似文献   

2.
Summary Many dogs are found to be unsuitable for training as guide dogs for the blind. Consequently the Royal Guide Dogs for the Blind Association of Australia has embarked on a breeding program to produce a strain of labrador dogs which is suitable for guide dog training.The most common reasons for rejecting dogs are fearfulness, dog distraction, excitability, health and physical reasons and hip dysplasia. The selection program seems to have been successful in improving the success rate mainly by lowering fearfulness, but there has not been a continuing improvement. This is probably due to continual introduction of dogs from other populations into the breeding program.Males suffer from a higher rejection rate due to dog distraction and a lower rejection rate due to fearfulness and excitability than females, so that there is little sex difference in overall success rate.The heritability of success (0.44) is high enough to predict further progress from selection, again mainly against fearfulness.Variation in environment prior to 6 weeks of age, in age when dogs were placed into a private home and in age when males were castrated, had little effect on the success rate.  相似文献   

3.
Domesticated dogs occasionally exhibit predatory behaviour towards domestic sheep when running loose in pasture. Both young and old dogs of either sex may chase sheep. Electronic dog collars applying electric shocks are utilised as one method of training dogs to refrain from attacking sheep. This device is used for a number of other training purposes which have raised concern for the welfare of the dogs being trained. This study aims at testing long-term learning effects of previous sheep tests on sheep chasing in hunting dog breeds (Norwegian elkhounds (grey), English setters, and hare hunting dogs), in particular with use of electronic dog collars, in addition to uncovering potential secondary negative effects on dogs' behaviour and mental stability. The dogs (N=114) were subjected to three tests for two subsequent years, the second year being reported here. Dogs were tested for reactions to different stimuli, including a sheep, in a path test. In a sheep confrontation test, dogs were fenced in with a sheep group and given el. shocks when approaching 1-2m from sheep. A questionnaire to the dog owners reported differences in dogs' behaviour between the years.Dogs showed weaker or delayed behavioural responses in both tests in the second year. No dogs showed interest in or attacked a lone sheep in the path test in the second year, while almost two thirds of them did so the first year. In the sheep confrontation test, the dogs exhibited comparatively hesitant initial hunting motivation the second year, being more evident in dogs which received el. shocks the first year. No dogs chased or attacked sheep as their first response in this test, while half of them did so the first year. The proportion of dogs attacking sheep during the entire test was reduced to almost one fourth. The number of el. shocks administered reduced by the second year, and only one of the dogs that received el. shocks the first year received el. shocks the second year. The owners reported no negative effect on the dogs' behaviour during the year ensuing el. shock treatment. Eighteen of the 24 dogs reported by owners to exhibit behavioural changes lost their previous interest in sheep.The second-year tests indicate that aversive conditioning with the use of electronic dog collar may be an efficient method for reducing the probability of a dog chasing or attacking grazing sheep. No adverse effects were observed with our test procedure.  相似文献   

4.
In the last 50 years, there has been a growing need for storage and management systems for the production and maintenance of large numbers of dogs. Unwanted dogs and strays, detained in kennels, stay for various lengths of time. Large kennels also produce dogs for sale as companion animals, for the service dog industry (police and guide dogs), for biomedical research, and for use by dog food companies. Across the United States, literally tens of thousands of dogs are born in kennels and spend their lives in kennels. The laboratory dog, the kennel dog, the service dog, and the companion dog are in an evolutionary transition period, accompanied by concomitant adaptation to stresses signaled by a high frequency of genetic disease and behavioral abnormalities. For kennel enrichment programs, such as socialization and exercise, the modern kenneled dog is a genetically moving target. Specific recommendations apply neither to all breeds nor to the variations within a single breed.  相似文献   

5.
It is often claimed that certain behavioral problems in domestic dogs can be triggered by the games played by dog and caregiver (owner). In this study, we examine possible links between the types of games played and dimensions of the dog-owner relationship that are generally considered to affect such problems. Fifty dog-owner partnerships were filmed during 3-min play sessions in which the owner was allowed to choose the games played. All partnerships then undertook a 1-hr test designed to measure elements of behavior commonly ascribed to "dominance" and "attachment." Principal components analysis of the data produced 2 dominance-related factors (Amenability and Confident Interactivity) and 4 factors describing aspects of attachment (Nonspecific Attention Seeking, Preference for Owner, Preference for Unfamiliar Person, and Separation-Related Behavior). Amenability, in particular, varied significantly between breeds. In the study, we then compared types of games played to each of these factors. Dogs playing rough-and-tumble scored higher for Amenability and lower on Separation-Related Behavior than did dogs playing other types of games. Dogs playing tug-of-war and fetch scored high on Confident Interactivity. Winning or losing these games had no consistent effect on their test scores. If the dog started the majority of the games, the dog was significantly less amenable and more likely to exhibit aggression. The results suggest that how dogs play reflects general attributes of their temperament and relationship with their owner. This study provides no evidence that games play a major deterministic role on dominance dimensions of dog-human relationships, but the results suggest that playing games involving considerable body contact may affect attachment dimensions.  相似文献   

6.
Trained service dogs assist and also add pride, self-reliance, and personal satisfaction to an individual's daily life. However, well-bred, trained dogs are very expensive. To explore decreasing the cost of a service dog by increasing the number of dogs successfully completing training, the authors analyzed tasks that service dogs are expected to perform, measuring some of the inherent physical stresses the dogs encounter and considering training techniques to better prepare the dogs for more successful completion of tasks. Observing working dogs, the authors found that undue stress was placed on many of the dogs while performing tasks; that motivational gestures for performance were not fully extended; and that, many times, handlers did not instruct the dogs properly. The working dogs observed often were required to perform tasks that put them at risk of injury and performance failure. Important future considerations for training and handling working dogs will include proper training of handlers and a better understanding of the complexities of the instinctive and physical capabilities and limitation of dogs.  相似文献   

7.
A detector dog for screwworms (Diptera: Calliphoridae)   总被引:1,自引:0,他引:1  
A male German wirehaired pointer, Canis familiaris L., was trained to search for and locate screwworm, Cochliomyia hominivorax (Coquerel); pupae; and animals infested with screwworms. The command, "find it" led to the detection of a screwworm-infested animal and the command "search" led to the detection of screwworm pupae. After approximately 5 mo of training, the dog could detect screwworm-infested animals. After 3 mo more of training, the dog could detect screwworm pupae. Through 7 August 1989, the dog had a success rate of 100% (265 tests) with training dummies and 94.7% (18 successes for 19 tests) with screwworm-infested animals, for an overall success rate of 99.7% (285 successes for 286 tests). Use of detector dogs at quarantine stations could result in increased efficiency, economic savings, and decreased possibility of reintroduction of screwworms into eradicated areas.  相似文献   

8.
Book Review     
《Anthrozo?s》2013,26(2):173-188
ABSTRACT

Previous studies conducted in the United States and Venezuela have demonstrated that people can correctly match portraits of unknown purebred dogs with their owners at statistically significant levels, suggesting that the popular belief in dog–owner physical resemblance is empirically valid. We investigated the perceived physical resemblance of dog–owner pairs in Japan, where the owners are racially more homogenous than in the countries in which the previous studies were conducted. In experiment 1, the matching performance by naïve judges was statistically significant, and a supplementary test suggested that perceived dog–owner physical resemblance plays a critical role in this. Experiment 2 presented a new procedure to test the perceived dog–owner physical resemblance and demonstrated that two-thirds of the judges selected a set of 20 real dog–owner pairs over a set of 20 fake dog–owner pairs, irrespective of whether it was an ownership-guessing task or a resemblance-based choice task. The ability to match correct dog–owner pairs (experiment 1) and the sensitivity to differentiate between real and fake dog–owner pairs (experiment 2) were not unique to the characteristics of the judges (e.g., whether or not they were dog lovers) because the task performance was independent of any measured judge-related factor. These results, taken together, provide another piece of positive evidence for the popular belief that there is a physical resemblance between dogs and their owners. Furthermore, the demonstration of dog–owner physical resemblance with racially homogeneous owner samples supports the generality and robustness of this phenomenon. The mechanism underlying this phenomenon (i.e., owners' selection of dogs that look like themselves or the convergence of appearance over time), however, remains to be elucidated by future studies.  相似文献   

9.
Bull breeds are commonly kept as companion animals, but the pit bull terrier is restricted by breed-specific legislation (BSL) in parts of the United States and throughout the United Kingdom. Shelter workers must decide which breed(s) a dog is. This decision may influence the dog's fate, particularly in places with BSL. In this study, shelter workers in the United States and United Kingdom were shown pictures of 20 dogs and were asked what breed each dog was, how they determined each dog's breed, whether each dog was a pit bull, and what they expected the fate of each dog to be. There was much variation in responses both between and within the United States and United Kingdom. UK participants frequently labeled dogs commonly considered by U.S. participants to be pit bulls as Staffordshire bull terriers. UK participants were more likely to say their shelters would euthanize dogs deemed to be pit bulls. Most participants noted using dogs' physical features to determine breed, and 41% affected by BSL indicated they would knowingly mislabel a dog of a restricted breed, presumably to increase the dog's adoption chances.  相似文献   

10.
《Anthrozo?s》2013,26(4):457-473
ABSTRACT

Many displaced dogs are unable to find new homes in developed countries, including Australia, each year, even though demand for dogs in general remains high. Understanding community attitudes towards shelter dogs and beliefs about common shelter practices, particularly behavioral assessments conducted by shelters, may help shed light on this issue. To investigate what current and potential dog owners think about shelter dogs, we used an internet-based survey to probe the beliefs and attitudes of 1647 self-selected adult participants, using the online Public Attitudes towards Animal Welfare Shelter-Dogs (PAAWS-D) Survey. Over 80% of the sample indicated they would be likely or very likely to obtain a future pet dog from an animal shelter or rescue organization. Nonetheless, one-third of the participants believed that adult shelter dogs often have behavioral problems. Most participants were aware of routine shelter procedures, such as health and behavioral checks, and the consequences of a dog failing these. Moreover, most participants considered the assessment of shelter dog behavior, using scientific methods, for adoption suitability important. These findings may be used to inform strategies to increase the number of shelter dogs adopted, by clarifying the content of tests used to assess adoption suitability. This could be complemented by daily training and rehabilitation programs to improve shelter dog behavior, increase adoptability, and enhance public perceptions of shelter dogs.  相似文献   

11.
Family dogs and dog owners offer a potentially powerful way to conduct citizen science to answer questions about animal behavior that are difficult to answer with more conventional approaches. Here we evaluate the quality of the first data on dog cognition collected by citizen scientists using the Dognition.com website. We conducted analyses to understand if data generated by over 500 citizen scientists replicates internally and in comparison to previously published findings. Half of participants participated for free while the other half paid for access. The website provided each participant a temperament questionnaire and instructions on how to conduct a series of ten cognitive tests. Participation required internet access, a dog and some common household items. Participants could record their responses on any PC, tablet or smartphone from anywhere in the world and data were retained on servers. Results from citizen scientists and their dogs replicated a number of previously described phenomena from conventional lab-based research. There was little evidence that citizen scientists manipulated their results. To illustrate the potential uses of relatively large samples of citizen science data, we then used factor analysis to examine individual differences across the cognitive tasks. The data were best explained by multiple factors in support of the hypothesis that nonhumans, including dogs, can evolve multiple cognitive domains that vary independently. This analysis suggests that in the future, citizen scientists will generate useful datasets that test hypotheses and answer questions as a complement to conventional laboratory techniques used to study dog psychology.  相似文献   

12.

Background

Canine Hip Dysplasia (CHD) is a common inherited disease that affects dog wellbeing and causes a heavy financial and emotional burden to dog owners and breeders due to secondary hip osteoarthritis. The Orthopedic Foundation for Animals (OFA) initiated a program in the 1960''s to radiograph hip and elbow joints and release the OFA scores to the public for breeding dogs against CHD. Over last four decades, more than one million radiographic scores have been released.

Methodology/Principal Findings

The pedigrees in the OFA database consisted of 258,851 Labrador retrievers, the major breed scored by the OFA (25% of total records). Of these, 154,352 dogs had an OFA hip score reported between 1970 and 2007. The rest of the dogs (104,499) were the ancestors of the 154,352 dogs to link the pedigree relationships. The OFA hip score is based on a 7-point scale with the best ranked as 1 (excellent) and the worst hip dysplasia as 7. A mixed linear model was used to estimate the effects of age, sex, and test year period and to predict the breeding value for each dog. Additive genetic and residual variances were estimated using the average information restricted maximum likelihood procedure. The analysis also provided an inbreeding coefficient for each dog. The hip scores averaged 1.93 (±SD = 0.59) and the heritability was 0.21. A steady genetic improvement has accrued over the four decades. The breeding values decreased (improved) linearly. By the end of 2005, the total genetic improvement was 0.1 units, which is equivalent to 17% of the total phenotypic standard deviation.

Conclusion/Significance

A steady genetic improvement has been achieved through the selection based on the raw phenotype released by the OFA. As the heritability of the hip score was on the low end (0.21) of reported ranges, we propose that selection based on breeding values will result in more rapid genetic improvement than breeding based on phenotypic selection alone.  相似文献   

13.
The excretory and secretory antigens from the evaginated scoleces of Taenia ovis were collected for 3 days in vitro, and used in an ELISA test to detect antibodies to T. ovis in the serum of dogs. When tested on sequentially collected sera, diagnostic ELISA values could be detected in many dogs 4 wk after infection, and remained for an average of a further 4 wk after worms were removed from dogs with an anthelmintic. Using an ELISA discriminant value that eliminated all false positives from 70 uninfected laboratory dog sera and from 57 uninfected farm dog sera, 54/62 true positives were found in sera from dogs infected with various numbers of T. ovis for various intervals. Sera from dogs infected with T. hydatigena gave 11/15 false positive reactions, whereas sera from 15 dogs infected with Echinococcus granulosus or 7 dogs infected with T. pisiformis were all negative. For T. ovis the test had a high repeatability, was not greatly influenced by the number of worms carried by the dog and higher titres were correlated with long-standing infections. Approximately 1,000 scoleces could be recovered from each experimentally infected sheep. Using the ELISA test with undiluted antigen and serum diluted 1:40, approximately 10 sera could be tested in duplicate with the excretions and secretions from each T. ovis scolex.  相似文献   

14.
Sheep grazing on unfenced mountain pasture may be attacked by loose dogs, which may chase and kill sheep and separate lambs from their mothers. We have earlier shown that testing dogs individually towards sheep with an electronic dog collar may effectively reduce the chasing propensity 1 year later. The aim of this study was to investigate whether and how a non-chasing and a chasing companion dog influence sheep chasing in test dogs (20 Norwegian Elkhounds, grey), and whether this varies with sex or age. The test dogs' predatory behaviour towards sheep was examined by observation of the dogs in a fenced enclosure with sheep in 5min tests together with, first, a non-chasing (Hamilton stoever, a hound breed) and 2-3 days later a chasing (Border collie) companion dog. Physical contact with sheep was prevented. Initially, the test dogs exhibited a higher chasing motivation towards sheep in tests with a chasing, as compared with a non-chasing, companion (P<0.001). During the entire test, 60% of the dogs attacked sheep when accompanied by the non-chaser. All dogs attacked sheep when the chasing companion was present (P=0.008), although in only 8 of 20 cases the companion dog chased simultaneously with the test dog. In the chasing-companion tests, the attack latency was shorter (P<0.001) than in tests with a non-chasing companion. The attack severity was higher when attacking alone than when attacking together with the chasing companion (P=0.033). In these tests, the higher the attack severity, the shorter was the attack latency (P=0.006). A sequence analysis on chasing-companion tests showed that test dogs generally started with observing or showing interest in sheep, followed by attacks, which increased in severity. No sex differences were observed. In non-chasing companion tests, dogs aged up to 2.5 years exhibited a weaker initial hunting motivation than older dogs (P=0.025), but during the entire test were more inclined to attack (P=0.019). Taken together, our findings indicate that a companion dog showing intentions of predatory behaviour stimulates predatory chase in another dog, while a non-chasing companion has a limited influence on this. In tests certifying dogs for their refrainment of chasing sheep, well trained Border collies approaching sheep on command might be used to reveal the full predatory potential of the dog being tested.  相似文献   

15.
The sandwich enzyme linked immunosorbent assay (ELISA) was used as a diagnostic test for Echinococcus granulosus infection by detecting coproantigens in 94 stray dogs Canis familiaris and eight red foxes (Vulpes vulpes) from northern Jordan. The results were analyzed in relation to actual helminth infection as revealed by necropsy. The infection rate of dogs with E. granulosus was 13.8% with a worm load ranging between 3-> 10,000 per infected dog. In contrast, eight of 13 E. granulosus infected dogs were coproantigen positive (overall sensitivity 61.5%). The sensitivity increased to 87.5% and 100% in dogs harboring > 20 and > 100 worms/dog, respectively. The specificity of coproantigen-ELISA was 91%. The greatest cross-reactivity was found in dogs infected with Dipylidium caninum. The positive and negative predictive values for the coproantigen-ELISA test were 50% and 94.2%, respectively. Thus, a coproantigen negative dog is most probably truly negative for E. granulosus. In contrast, a coproantigen positive dog may not be truly positive for E. granulosus, except if it has a high worm burden of > 100 worms/animal.  相似文献   

16.

Background

Rabies still poses a significant human health problem throughout most of Africa, where the majority of the human cases results from dog bites. Mass dog vaccination is considered to be the most effective method to prevent rabies in humans. Our objective was to systematically review research articles on dog rabies parenteral vaccination coverage in Africa in relation to dog accessibility and vaccination cost recovery arrangement (i.e.free of charge or owner charged).

Methodology/Principal Findings

A systematic literature search was made in the databases of CAB abstracts (EBSCOhost and OvidSP), Scopus, Web of Science, PubMed, Medline (EBSCOhost and OvidSP) and AJOL (African Journal Online) for peer reviewed articles on 1) rabies control, 2) dog rabies vaccination coverage and 3) dog demography in Africa. Identified articles were subsequently screened and selected using predefined selection criteria like year of publication (viz. ≥ 1990), type of study (cross sectional), objective(s) of the study (i.e. vaccination coverage rates, dog demographics and financial arrangements of vaccination costs), language of publication (English) and geographical focus (Africa). The selection process resulted in sixteen peer reviewed articles which were used to review dog demography and dog ownership status, and dog rabies vaccination coverage throughout Africa. The main review findings indicate that 1) the majority (up to 98.1%) of dogs in African countries are owned (and as such accessible), 2) puppies younger than 3 months of age constitute a considerable proportion (up to 30%) of the dog population and 3) male dogs are dominating in numbers (up to 3.6 times the female dog population). Dog rabies parenteral vaccination coverage was compared between “free of charge” and “owner charged” vaccination schemes by the technique of Meta-analysis. Results indicate that the rabies vaccination coverage following a free of charge vaccination scheme (68%) is closer to the World Health Organization recommended coverage rate (70%) than the achieved coverage rate in owner-charged dog rabies vaccination schemes (18%).

Conclusions/Significance

Most dogs in Africa are owned and accessible for parenteral vaccination against rabies if the campaign is performed “free of charge”.  相似文献   

17.
Brachycephalic obstructive airway syndrome (BOAS) is an important health and welfare problem in several popular dog breeds. Whole-body barometric plethysmography (WBBP) is a non-invasive method that allows safe and repeated quantitative measurements of respiratory cycles on unsedated dogs. Here respiratory flow traces in French bulldogs from the pet population were characterised using WBBP, and a computational application was developed to recognise affected animals. Eighty-nine French bulldogs and twenty non-brachycephalic controls underwent WBBP testing. A respiratory functional grading system was used on each dog based on respiratory signs (i.e. respiratory noise, effort, etc.) before and after exercise. For development of an objective BOAS classifier, functional Grades 0 and I were considered to have insignificant clinical signs (termed here BOAS-) and Grades II and III to have significant signs (termed here BOAS+). A comparison between owner-perception of BOAS and functional grading revealed that 60 % of owners failed to recognise BOAS in dogs that graded BOAS+ in this study.WBBP flow traces were found to be significantly different between non-brachycephalic controls and Grade 0 French bulldogs; BOAS- and BOAS+ French bulldogs. A classifier was developed using quadratic discriminant analysis of the respiratory parameters to distinguish BOAS- and BOAS + French bulldogs, and a BOAS Index was calculated for each dog. A cut-off value of the BOAS Index was selected based on a receiver operating characteristic (ROC) curve. Sensitivity, specificity, positive predictive value, and negative predictive value of the classifier on the training group (n=69) were 0.97, 0.93, 0.95, and 0.97, respectively. The classifier was validated using a test group of French bulldogs (n=20) with an accuracy of 0.95. WBBP offers objective screening for the diagnosis of BOAS in French Bulldogs. The technique may be applied to other brachycephalic breeds affected by BOAS, and possibly to other respiratory disease in dogs.  相似文献   

18.
This article reports the first known study on dogs in Port-au-Prince. Interviews with 1,290 residents provided information on 1,804 dogs. More than 57.7% of homes kept dogs. Not all the dogs received vaccinations for rabies (41.6%), even though 28.2% of households had had a household member bitten by a dog. Although the "owned" dog population had decreased as a result of the earthquake in January 2010, the number of roaming dogs appeared to have been uninfluenced by the disaster. Given that 64.8% of dogs probably had access to the street and only 6.0% of the females were spayed, to humanely contain the dog population will require both confinement and neutering. Although roaming dogs were considered a nuisance by 63.3% of respondents, 42.6% of households fed dogs they did not own.  相似文献   

19.
It is often claimed that certain behavioral problems in domestic dogs can be triggered by the games played by dog and caregiver (owner). In this study, we examine possible links between the types of games played and dimensions of the dog-owner relationship that are generally considered to affect such problems. Fifty dog-owner partnerships were filmed during 3-min play sessions in which the owner was allowed to choose the games played. All partnerships then undertook a 1-hr test designed to measure elements of behavior commonly ascribed to “dominance ”and “attachment. ”Principal components analysis of the data produced 2 dominance-related factors (Amenability and Confident Interactivity) and 4 factors describing aspects of attachment (Nonspecific Attention Seeking, Preference for Owner, Preference for Unfamiliar Person, and Separation-Related Behavior). Amenability, in particular, varied significantly between breeds. In the study, we then compared types of games played to each of these factors. Dogs playing rough-and-tumble scored higher for Amenability and lower on Separation-Related Behavior than did dogs playing other types of games. Dogs playing tug-of-war and fetch scored high on Confident Interactivity. Winning or losing these games had no consistent effect on their test scores. If the dog started the majority of the games, the dog was significantly less amenable and more likely to exhibit aggression. The results suggest that how dogs play reflects general attributes of their temperament and relationship with their owner. This study provides no evidence that games play a major deterministic role on dominance dimensions of dog-human relationships, but the results suggest that playing games involving considerable body contact may affect attachment dimensions.  相似文献   

20.
Dogs, in the age range 1–3 years old, were randomly selected from the largest animal insurance database in Sweden for inclusion in the study. The study was performed in 1997, and a total of 680 dog owners were selected for the study. A total of 461 dog owners completed the survey, at an overall response rate of 68%. Data was compared to a recent gallup performed on a sample of all dogs in Sweden. The demographic statistics of the insured dog population were in many aspects similar to the total dog population of Sweden. Typical for both insured dogs and the total population of dogs were a low proportion of neutered dogs, that many dogs were bought at an early age, that many dogs were in contact with a "breeder" when sold, and a similar profile of health status. However, "dog breeders" seemed to have their dogs insured to a higher extent than the general dog owner. It was concluded that as the populations were alike in many respects, it is reasonable to use the insurance database for epidemiological studies on diet and exercise in Swedish dogs.  相似文献   

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