The Experts below are selected from a list of 324 Experts worldwide ranked by ideXlab platform
Stanley D Gehrt - One of the best experts on this subject based on the ideXlab platform.
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Raccoon contact networks predict seasonal susceptibility to rabies outbreaks and limitations of vaccination.
Journal of Animal Ecology, 2015Co-Authors: Jennifer J. H. Reynolds, Stanley D Gehrt, Ben T Hirsch, Meggan E. CraftAbstract:1. Infectious disease transmission often depends on the contact structure of host populations. Although it is often challenging to capture the contact structure in wild animals, new technology has enabled biologists to obtain detailed temporal information on wildlife social contacts. In this study, we investigated the effects of Raccoon contact patterns on rabies spread using network modelling. 2. Raccoons (Procyon lotor) play an important role in the maintenance of rabies in the United States. It is crucial to understand how contact patterns influence the spread of rabies in Raccoon populations in order to design effective control measures and to prevent transmission to human populations and other animals. 3. We constructed a dynamic system of contact networks based on empirical data from proximity logging collars on a wild suburban Raccoon population and then simulated rabies spread across these networks. Our contact networks incorporated the number and duration of Raccoon interactions. We included differences in contacts according to sex and season, and both short-term acquaintances and long-term associations. Raccoons may display different behaviours when infectious, including aggression (furious behaviour) and impaired mobility (dumb behaviour); the network model was used to assess the impact of potential behavioural changes in rabid Raccoons. We also tested the effectiveness of different vaccination coverage levels. 4. Our results demonstrate that when rabies enters a suburban Raccoon population, the likelihood of a disease outbreak affecting the majority of the population is high. Both the magnitude of rabies outbreaks and the speed of rabies spread depend strongly on the time of year that rabies is introduced into the population. When there is a combination of dumb and furious behaviours in the rabid Raccoon population, there are similar outbreak sizes and speed of spread to when there are no behavioural changes due to rabies infection. 5. By incorporating detailed data describing the variation in Raccoon contact rates into a network modelling approach, we were able to show that suburban Raccoon populations are highly susceptible to rabies outbreaks, that the risk of large outbreaks varies seasonally and that current vaccination target levels may be inadequate to prevent the spread of rabies within these populations. Our findings provide new insights into rabies dynamics in Raccoon populations and have important implications for disease control.
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reduction of baylisascaris procyonis eggs in Raccoon latrines suburban chicago illinois usa
Emerging Infectious Diseases, 2014Co-Authors: Kristen Page, Timothy J Smyser, Elise Dunkerton, Emily Gavard, Bruce Larkin, Stanley D GehrtAbstract:Baylisascaris procyonis, a common roundworm of Raccoons, causes severe or fatal human infections, often in suburban areas. To evaluate the effectiveness of a baiting strategy requiring minimal labor, we distributed medicated baits near Raccoon latrines in suburban Chicago, Illinois, USA. This strategy lowered B. procyonis prevalence in Raccoons, possibly reducing risk to humans.
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patterns of latrine use by Raccoons procyon lotor and implication for baylisascaris procyonis transmission
Journal of Wildlife Diseases, 2014Co-Authors: Ben T Hirsch, Suzanne Prange, Stephanie A Hauver, Stanley D GehrtAbstract:Mammals often use latrine sites for defecation, yet little is known about patterns of latrine use in many common species such as Raccoons (Procyon lotor). Because Raccoon latrines are important foci for the transmission of Raccoon roundworm (Baylisascaris procyonis), documenting metrics of Raccoon latrine use may have public health implications. Although some studies have provided evidence that multiple Raccoons visit single latrine sites, exact latrine visitation patterns of Raccoons have never been documented. We monitored Raccoon latrine usage using proximity- logging collars placed at 15 latrine sites. We found that latrine sites were visited by multiple Raccoons (range 1-7), and Raccoons visited as many as six latrines during a 2-wk period. No sex differences were found in the number of latrines visited or time spent during visits. We posit that the use of multiple latrine sites by Raccoons may lead to the pattern that rates of B. procyonis infection at latrines are greater than infection rates found in individual Raccoon fecal samples. This in turn could lead to greater transmission of B. procyonis to paratenic hosts. Our results support the conclusion that Raccoon latrines can be major foci for the infection and spread of B. procyonis.
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Raccoon social networks and the potential for disease transmission.
PloS one, 2013Co-Authors: Ben T Hirsch, Suzanne Prange, Stephanie A Hauver, Stanley D GehrtAbstract:Raccoons are an important vector of rabies and other pathogens. The degree to which these pathogens can spread through a Raccoon population should be closely linked to association rates between individual Raccoons. Most studies of Raccoon sociality have found patterns consistent with low levels of social connectivity within populations, thus the likelihood of direct pathogen transmission between Raccoons is theoretically low. We used proximity detecting collars and social network metrics to calculate the degree of social connectivity in an urban Raccoon population for purposes of estimating potential pathogen spread. In contrast to previous assumptions, Raccoon social association networks were highly connected, and all individuals were connected to one large social network during 15 out of 18 months of study. However, these metrics may overestimate the potential for a pathogen to spread through a population, as many of the social connections were based on relatively short contact periods. To more closely reflect varying probabilities of pathogen spread, we censored the Raccoon social networks based on the total amount of time spent in close proximity between two individuals per month. As this time criteria for censoring the social networks increased from one to thirty minutes, corresponding measures of network connectivity declined. These findings demonstrate that Raccoon populations are much more tightly connected than would have been predicted based on previous studies, but also point out that additional research is needed to calculate more precise transmission probabilities by infected individuals, and determine how disease infection changes normal social behaviors.
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Age, but not Sex or Genetic Relatedness, Shapes Raccoon Dominance Patterns
Ethology, 2013Co-Authors: Stephanie A Hauver, Ben T Hirsch, Suzanne Prange, Jean Dubach, Stanley D GehrtAbstract:Raccoons are generally regarded as solitary, yet several studies have found that Raccoons frequently form social affiliations. One benefit to sociality in many mammal species is that relatives and close associates can form coalitions against third parties during agonistic encounters. We tested whether Raccoon dominance patterns were influenced by age, sex, genetic relatedness, and association patterns at two anthropogenic feeding stations in an urban forest. We found that genetic relatedness had no significant effect on patterns of agonism at one of the feeding stations. At the second feeding station, Raccoons were more likely to act aggressively toward close relatives, which is opposite of the predicted pattern. However, when we controlled for the number of times Raccoons arrived at feeding stations in close proximity, the effect of relatedness on dominance patterns was not significant at either feeding station. These results suggest that relatedness plays little or no role in shaping dominance patterns of Raccoons. Older Raccoons were ranked significantly higher in the dominance hierarchies regardless of sex. This pattern leads us to conclude that age is the primary factor driving the outcome of aggressive interactions in Raccoons at our study site. Despite frequent social interactions at the study site, the patterns of Raccoon dominance more closely resemble patterns found in solitary animals. To confirm the generality of these results and to better understand the evolution of Raccoon social behavior, similar studies need to be undertaken in other Raccoon populations.
Jane Parmley - One of the best experts on this subject based on the ideXlab platform.
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epidemiology of antimicrobial resistance in escherichia coli isolates from Raccoons procyon lotor and the environment on swine farms and conservation areas in southern ontario
PLOS ONE, 2016Co-Authors: Kristin J Bondo, David L Pearl, Nicol Janecko, Patrick Boerlin, Richard J Reidsmith, Jane ParmleyAbstract:Antimicrobial resistance is a global threat to livestock, human and environmental health. Although resistant bacteria have been detected in wildlife, their role in the epidemiology of antimicrobial resistance is not clear. Our objective was to investigate demographic, temporal and climatic factors associated with carriage of antimicrobial resistant Escherichia coli in Raccoons and the environment. We collected samples from Raccoon paws and feces and from soil, manure pit and dumpsters on five swine farms and five conservation areas in Ontario, Canada once every five weeks from May to November, 2011-2013 and tested them for E. coli and susceptibility to 15 antimicrobials. Of samples testing positive for E. coli, resistance to ≥ 1 antimicrobials was detected in 7.4% (77/1044; 95% CI, 5.9-9.1) of Raccoon fecal samples, 6.3% (23/365; 95% CI, 4.0-9.3) of paw samples, 9.6% (121/1260; 8.0-11.4) of soil samples, 57.4% (31/54; 95% CI, 43.2-70.8) of manure pit samples, and 13.8% (4/29; 95% CI, 3.9-31.7) of dumpster samples. Using univariable logistic regression, there was no significant difference in the occurrence of resistant E. coli in Raccoon feces on conservation areas versus farms; however, E. coli isolates resistant to ≥ 1 antimicrobials were significantly less likely to be detected from Raccoon paw samples on swine farms than conservation areas and significantly more likely to be detected in soil samples from swine farms than conservation areas. Resistant phenotypes and genotypes that were absent from the swine farm environment were detected in Raccoons from conservation areas, suggesting that conservation areas and swine farms may have different exposures to resistant bacteria. However, the similar resistance patterns and genes in E. coli from Raccoon fecal and environmental samples from the same location types suggest that resistant bacteria may be exchanged between Raccoons and their environment.
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impact of season demographic and environmental factors on salmonella occurrence in Raccoons procyon lotor from swine farms and conservation areas in southern ontario
PLOS ONE, 2016Co-Authors: Kristin J Bondo, David L Pearl, Nicol Janecko, Patrick Boerlin, Richard J Reidsmith, Jane ParmleyAbstract:Salmonella has been detected in the feces of many wildlife species, including Raccoons (Procyon lotor), but little is known about the epidemiology of Salmonella in wildlife living in different habitat types. Our objective was to investigate demographic, temporal, and climatic factors associated with the carriage of Salmonella in Raccoons and their environment on swine farms and conservation areas. Using a repeated cross-sectional study design, we collected fecal samples from Raccoons and environmental samples (soil, manure pits, dumpsters) on 5 swine farms and 5 conservation areas in Ontario, Canada once every five weeks from May to November, 2011–2013. Salmonella was detected in 26% (279/1093; 95% CI 22.9–28.2) of Raccoon fecal samples, 6% (88/1609; 95% CI 4.5–6.8) of soil samples, 30% (21/69; 95% CI 20.0–42.7) of manure pit samples, and 23% (7/31; 95% CI 9.6–41.0) of dumpster samples. Of samples testing positive for Salmonella, antimicrobial resistance was detected in 5% (14/279; 95% CI 2.8–8.3) of Raccoon fecal, 8% (7/89; 95% CI 3.2–15.5) of soil, 10% (2/21; 95% CI 1.2–30.4) of manure pit, and 0/7 dumpster samples. Using multi-level multivariable logistic regression analyses, we found location type (swine farm or conservation area) was not a significant explanatory variable for Salmonella occurrence in Raccoon feces or soil (p > 0.05). However, detection of Salmonella in Raccoon feces was associated with rainfall, season, and sex with various interaction effects among these variables. We detected a variety of Salmonella serovars that infect humans and livestock in the feces of Raccoons indicating that Raccoons living near humans, regardless of location type, may play a role in the epidemiology of salmonellosis in livestock and humans in southwestern Ontario.
Nicol Janecko - One of the best experts on this subject based on the ideXlab platform.
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epidemiology of antimicrobial resistance in escherichia coli isolates from Raccoons procyon lotor and the environment on swine farms and conservation areas in southern ontario
PLOS ONE, 2016Co-Authors: Kristin J Bondo, David L Pearl, Nicol Janecko, Patrick Boerlin, Richard J Reidsmith, Jane ParmleyAbstract:Antimicrobial resistance is a global threat to livestock, human and environmental health. Although resistant bacteria have been detected in wildlife, their role in the epidemiology of antimicrobial resistance is not clear. Our objective was to investigate demographic, temporal and climatic factors associated with carriage of antimicrobial resistant Escherichia coli in Raccoons and the environment. We collected samples from Raccoon paws and feces and from soil, manure pit and dumpsters on five swine farms and five conservation areas in Ontario, Canada once every five weeks from May to November, 2011-2013 and tested them for E. coli and susceptibility to 15 antimicrobials. Of samples testing positive for E. coli, resistance to ≥ 1 antimicrobials was detected in 7.4% (77/1044; 95% CI, 5.9-9.1) of Raccoon fecal samples, 6.3% (23/365; 95% CI, 4.0-9.3) of paw samples, 9.6% (121/1260; 8.0-11.4) of soil samples, 57.4% (31/54; 95% CI, 43.2-70.8) of manure pit samples, and 13.8% (4/29; 95% CI, 3.9-31.7) of dumpster samples. Using univariable logistic regression, there was no significant difference in the occurrence of resistant E. coli in Raccoon feces on conservation areas versus farms; however, E. coli isolates resistant to ≥ 1 antimicrobials were significantly less likely to be detected from Raccoon paw samples on swine farms than conservation areas and significantly more likely to be detected in soil samples from swine farms than conservation areas. Resistant phenotypes and genotypes that were absent from the swine farm environment were detected in Raccoons from conservation areas, suggesting that conservation areas and swine farms may have different exposures to resistant bacteria. However, the similar resistance patterns and genes in E. coli from Raccoon fecal and environmental samples from the same location types suggest that resistant bacteria may be exchanged between Raccoons and their environment.
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impact of season demographic and environmental factors on salmonella occurrence in Raccoons procyon lotor from swine farms and conservation areas in southern ontario
PLOS ONE, 2016Co-Authors: Kristin J Bondo, David L Pearl, Nicol Janecko, Patrick Boerlin, Richard J Reidsmith, Jane ParmleyAbstract:Salmonella has been detected in the feces of many wildlife species, including Raccoons (Procyon lotor), but little is known about the epidemiology of Salmonella in wildlife living in different habitat types. Our objective was to investigate demographic, temporal, and climatic factors associated with the carriage of Salmonella in Raccoons and their environment on swine farms and conservation areas. Using a repeated cross-sectional study design, we collected fecal samples from Raccoons and environmental samples (soil, manure pits, dumpsters) on 5 swine farms and 5 conservation areas in Ontario, Canada once every five weeks from May to November, 2011–2013. Salmonella was detected in 26% (279/1093; 95% CI 22.9–28.2) of Raccoon fecal samples, 6% (88/1609; 95% CI 4.5–6.8) of soil samples, 30% (21/69; 95% CI 20.0–42.7) of manure pit samples, and 23% (7/31; 95% CI 9.6–41.0) of dumpster samples. Of samples testing positive for Salmonella, antimicrobial resistance was detected in 5% (14/279; 95% CI 2.8–8.3) of Raccoon fecal, 8% (7/89; 95% CI 3.2–15.5) of soil, 10% (2/21; 95% CI 1.2–30.4) of manure pit, and 0/7 dumpster samples. Using multi-level multivariable logistic regression analyses, we found location type (swine farm or conservation area) was not a significant explanatory variable for Salmonella occurrence in Raccoon feces or soil (p > 0.05). However, detection of Salmonella in Raccoon feces was associated with rainfall, season, and sex with various interaction effects among these variables. We detected a variety of Salmonella serovars that infect humans and livestock in the feces of Raccoons indicating that Raccoons living near humans, regardless of location type, may play a role in the epidemiology of salmonellosis in livestock and humans in southwestern Ontario.
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SALMONELLA IN RaccoonS (PROCYON LOTOR) IN SOUTHERN ONTARIO, CANADA
Journal of Wildlife Diseases, 2011Co-Authors: Claire M. Jardine, Mike Allan, Nicol Janecko, Richard J. Reid-smith, Scott A. McewenAbstract:Numerous serotypes of Salmonella have been detected in a variety of wild animals, including Raccoons (Procyon lotor). Raccoons are common, mid-size omnivores that live in close association with people in urban and rural areas in Ontario. Although Raccoons are known to shed Salmonella, little is known about their potential long-term role in maintaining Salmonella infections. We sampled feces from Raccoons in three areas of Ontario: one primarily urban site around Niagara, one primarily rural site north of Guelph, and the grounds of the Toronto Zoo, in 2007 to identify which serotypes of Salmonella were commonly shed by Raccoons in southern Ontario. In addition, we conducted a longitudinal study at the Toronto Zoo site to determine if Raccoons remain persistently infected with Salmonella. Salmonella was found in 45% of samples. The prevalence of Salmonella in Raccoon feces ranged from 27% at the rural site to 65% at the urban site. We detected 16 serotypes of Salmonella in 83 positive samples. The most common serotype detected in Raccoons from the rural and zoo sites was Salmonella enterica serotype Typhimurium, whereas Salmonella Newport was detected most commonly in the urban site. Only one Raccoon of 11 that were captured in four or more consecutive trapping sessions shed the same Salmonella serotype for two consecutive months, suggesting that Raccoons regularly acquire new Salmonella serotypes from the environment.
Richard J Reidsmith - One of the best experts on this subject based on the ideXlab platform.
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epidemiology of antimicrobial resistance in escherichia coli isolates from Raccoons procyon lotor and the environment on swine farms and conservation areas in southern ontario
PLOS ONE, 2016Co-Authors: Kristin J Bondo, David L Pearl, Nicol Janecko, Patrick Boerlin, Richard J Reidsmith, Jane ParmleyAbstract:Antimicrobial resistance is a global threat to livestock, human and environmental health. Although resistant bacteria have been detected in wildlife, their role in the epidemiology of antimicrobial resistance is not clear. Our objective was to investigate demographic, temporal and climatic factors associated with carriage of antimicrobial resistant Escherichia coli in Raccoons and the environment. We collected samples from Raccoon paws and feces and from soil, manure pit and dumpsters on five swine farms and five conservation areas in Ontario, Canada once every five weeks from May to November, 2011-2013 and tested them for E. coli and susceptibility to 15 antimicrobials. Of samples testing positive for E. coli, resistance to ≥ 1 antimicrobials was detected in 7.4% (77/1044; 95% CI, 5.9-9.1) of Raccoon fecal samples, 6.3% (23/365; 95% CI, 4.0-9.3) of paw samples, 9.6% (121/1260; 8.0-11.4) of soil samples, 57.4% (31/54; 95% CI, 43.2-70.8) of manure pit samples, and 13.8% (4/29; 95% CI, 3.9-31.7) of dumpster samples. Using univariable logistic regression, there was no significant difference in the occurrence of resistant E. coli in Raccoon feces on conservation areas versus farms; however, E. coli isolates resistant to ≥ 1 antimicrobials were significantly less likely to be detected from Raccoon paw samples on swine farms than conservation areas and significantly more likely to be detected in soil samples from swine farms than conservation areas. Resistant phenotypes and genotypes that were absent from the swine farm environment were detected in Raccoons from conservation areas, suggesting that conservation areas and swine farms may have different exposures to resistant bacteria. However, the similar resistance patterns and genes in E. coli from Raccoon fecal and environmental samples from the same location types suggest that resistant bacteria may be exchanged between Raccoons and their environment.
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impact of season demographic and environmental factors on salmonella occurrence in Raccoons procyon lotor from swine farms and conservation areas in southern ontario
PLOS ONE, 2016Co-Authors: Kristin J Bondo, David L Pearl, Nicol Janecko, Patrick Boerlin, Richard J Reidsmith, Jane ParmleyAbstract:Salmonella has been detected in the feces of many wildlife species, including Raccoons (Procyon lotor), but little is known about the epidemiology of Salmonella in wildlife living in different habitat types. Our objective was to investigate demographic, temporal, and climatic factors associated with the carriage of Salmonella in Raccoons and their environment on swine farms and conservation areas. Using a repeated cross-sectional study design, we collected fecal samples from Raccoons and environmental samples (soil, manure pits, dumpsters) on 5 swine farms and 5 conservation areas in Ontario, Canada once every five weeks from May to November, 2011–2013. Salmonella was detected in 26% (279/1093; 95% CI 22.9–28.2) of Raccoon fecal samples, 6% (88/1609; 95% CI 4.5–6.8) of soil samples, 30% (21/69; 95% CI 20.0–42.7) of manure pit samples, and 23% (7/31; 95% CI 9.6–41.0) of dumpster samples. Of samples testing positive for Salmonella, antimicrobial resistance was detected in 5% (14/279; 95% CI 2.8–8.3) of Raccoon fecal, 8% (7/89; 95% CI 3.2–15.5) of soil, 10% (2/21; 95% CI 1.2–30.4) of manure pit, and 0/7 dumpster samples. Using multi-level multivariable logistic regression analyses, we found location type (swine farm or conservation area) was not a significant explanatory variable for Salmonella occurrence in Raccoon feces or soil (p > 0.05). However, detection of Salmonella in Raccoon feces was associated with rainfall, season, and sex with various interaction effects among these variables. We detected a variety of Salmonella serovars that infect humans and livestock in the feces of Raccoons indicating that Raccoons living near humans, regardless of location type, may play a role in the epidemiology of salmonellosis in livestock and humans in southwestern Ontario.
Kristen L Page - One of the best experts on this subject based on the ideXlab platform.
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development of an automated dispenser for the delivery of medicinal or vaccine laden baits to Raccoons procyon lotor
Journal of Wildlife Diseases, 2015Co-Authors: Timothy J Smyser, Kristen L Page, James V Redding, Crystal M Bevis, Robert K. SwihartAbstract:Abstract Medicinal baits are distributed to manage zoonotic diseases, including Raccoon (Procyon lotor) rabies, but efficient distribution strategies are needed for suburban environments. We developed an automated dispenser that transfers fishmeal polymer baits at user-specified intervals from a magazine to a receptacle fitted with a filter that exploits Raccoon dexterity to limit consumption by nontarget species. We introduce the concept of automated dispensers and describe bait removal success rates for Raccoons versus nontarget species. We monitored visitation with remote cameras after deploying a dispenser, programmed to present two baits per night, in three disjunct forest patches in northwest Indiana. Raccoons removed 72% of baits; nontarget, white-footed mice (Peromyscus leucopus) removed 11%; Virginia opossums (Didelphis virginiana) removed 9%. Bait removal success varied significantly between Raccoons (76%) and opossums (21%), improving bait delivery specificity relative to hand baiting. Accumula...
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the relationship between baylisascaris procyonis prevalence and Raccoon population structure
Journal of Parasitology, 2009Co-Authors: Kristen L Page, Stanley D Gehrt, Andrea Cascione, Kenneth F KellnerAbstract:Abstract Parasite transmission is a dynamic process that can be affected by factors including host and parasite population dynamics. Raccoons (Procyon lotor) are the definitive host of Baylisascaris procyonis, an intestinal roundworm. Transmission of this parasite has been linked to Raccoon behavior and human land-use patterns; however, we do not know the importance of host population structure. Therefore, the objective of this study was to determine the relationship between Raccoon population attributes and prevalence of B. procyonis. We necropsied 307 trapped or road-killed Raccoons collected during 2000–2006 from the Chicago area. In addition, we examined, via fecal samples (n = 433), the patterns of B. procyonis prevalence as they relate to population dynamics among 3 subpopulations within the larger study. Baylisascaris procyonis was seen in 39% of 307 necropsied Raccoons. There were differences in prevalence as a function of host age and sex. Baylisascaris procyonis was observed in 18% of 433 feca...
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land use effects on prevalence of Raccoon roundworm baylisascaris procyonis
Journal of Wildlife Diseases, 2008Co-Authors: Kristen L Page, Stanley D Gehrt, Nathaniel P RobinsonAbstract:The Raccoon (Procyon lotor) is the definitive host of Baylisascaris procyonis, a large intestinal roundworm that is zoonotic and can result in fatal or severe central nervous system disease in young children. Prevalence of infection among Raccoon populations often is high, and in the midwestern United States, B. procyonis has been reported in 68–82% of Raccoons. Raccoon populations have increased in response to changes in human land use, and often reach higher densities in urban and suburban landscapes than rural landscapes. However, shifts in foraging behavior among urban Raccoons could impact the transmission of B. procyonis if small vertebrate intermediate hosts are not a significant part of the Raccoon diet. The objective of this study was to compare prevalence of B. procyonis infection between urban and rural Raccoon populations on a regional scale. Necropsy was done on 204 Raccoons collected from September through February during 2000–2005 from seven states across the Midwest (regional sample). Bayl...
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measuring prevalence of Raccoon roundworm baylisascaris procyonis a comparison of common techniques
Wildlife Society Bulletin, 2005Co-Authors: Kristen L Page, Stanley D Gehrt, Kristin K Titcombe, Nathaniel P RobinsonAbstract:The Raccoon (Procyon lotor) is the definitive host of Baylisascaris procyonis, a large intestinal roundworm. The prevalence of infection among Raccoon populations often is high, and in the midwestern United States B. procyonis is documented in 68–82% of Raccoons. Because Raccoon populations appear to be increasing in response to changes in human land use and because B. procyonis is considered an emerging zoonotic disease, it is important to determine reliable methods to monitor prevalence of infection among Raccoons. We compared the relative sensitivity of 3 common methods used by wildlife biologists to determine prevalence in free-ranging Raccoon populations. We determined prevalence of infection among midwestern Raccoon populations from 456 Raccoon fecal samples, 742 Raccoon latrine samples, and 212 necropsies (gut analysis). We developed logistic regression models in order to predict the log likelihood of presence of B. procyonis in a given sample as a function of season, land use, and technique. Finally, we measured the sensitivity of fecal sampling by evaluating fecal samples taken from 72 necropsies for the presence of B. procyonis eggs. Necropsy analysis yielded the highest measure of prevalence (44%), followed by latrine samples (22.5%), and fecal samples (17.5%). Necropsy analysis explained the most variance in logistic models, suggesting that this is the most reliable method. However, this technique is labor-intensive and may not be the most efficient method for large-scale investigations of B. procyonis prevalence. Fecal analysis is a reliable method of determining prevalence among Raccoons as we observed B. procyonis eggs in 66% of fecal samples taken from positive necropsies. Latrine sampling may be the most efficient method and perhaps the best estimator of zoonotic potential; however, wildlife managers should realize that this measure often is an underestimate of prevalence among Raccoons and develop management plans accordingly.
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seed preferences and foraging by granivores at Raccoon latrines in the transmission dynamics of the Raccoon roundworm baylisascaris procyonis
Canadian Journal of Zoology, 2001Co-Authors: Kristen L Page, Robert K. Swihart, Kevin R. KazacosAbstract:Raccoons (Procyon lotor) habitually defecate at preferred sites (latrines). Feces at latrines often harbor eggs of the roundworm Baylisascaris procyonis, a parasite of Raccoons that is pathogenic to numerous species of small vertebrates. Undigested seeds are also commonly found in Raccoon feces, the composition varying with availability of seed types. Thus, feces at latrines may serve as a source of food and pose a mortality risk for small granivores. To examine this interaction, we manipulated the seed composition in feces at simulated Raccoon latrines and tested for differences in vertebrate visitation rates as a function of seed type. Treatments involved placing seeds, including corn, cherry ( Prunus virginiana), dogwood (Cornus racemosa), and a combination of the three types, at simulated Raccoon latrines. Using TrailmasterTM camera systems we documented 2406 vertebrate visits by 16 mammal and 11 bird species during 455 camera-nights. Small granivorous mammals, including white-footed mice (Peromyscus ...
