Publications by authors named "Jaime Rudd"

9 Publications

  • Page 1 of 1

Generalized dermatophytosis caused by in 8 juvenile black bears in California.

J Vet Diagn Invest 2021 Nov 28:10406387211061143. Epub 2021 Nov 28.

California Animal Health and Food Safety Laboratory System, University of California-Davis, CA, USA.

From 2014-2019, 8 juvenile black bears () from different geographic regions were presented to the California Department of Fish and Wildlife because of emaciation, alopecia, and exfoliative dermatitis that resulted in death or euthanasia. Autopsy and histopathology revealed that all 8 bears had generalized hyperkeratotic dermatitis, folliculitis, and furunculosis. Skin structures were heavily colonized by fungal hyphae and arthrospores; fungal cultures of skin from 7 bears yielded , a zoophilic dermatophyte reported only rarely in non-equid species. Additional skin conditions included mites (5), ticks (2), and coagulase-negative sp. infections (2). No other causes of morbidity or mortality were identified. Molecular comparisons performed at the University of Texas Fungal Reference Laboratory determined that all isolates produced identical banding patterns, potentially representing a clonal population. Dermatophytosis is commonly localized and limited to the stratum corneum of the epidermis and hair follicles. Generalized disease with dermal involvement is rare in immunocompetent individuals; illness, malnutrition, age, or immunosuppression may increase susceptibility. Underlying causes for the severe disease impact in these bears were not evident after physical or postmortem examination. The mechanism by which bears from different geographic locations had severe, -associated dermatophytosis from a potentially clonal dermatophyte could not be explained and warrants further investigation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1177/10406387211061143DOI Listing
November 2021

LEPTOSPIRA PREVALENCE AND ITS ASSOCIATION WITH RENAL PATHOLOGY IN MOUNTAIN LIONS (PUMA CONCOLOR) AND BOBCATS (LYNX RUFUS) IN CALIFORNIA, USA.

J Wildl Dis 2021 01;57(1):27-39

Department of Veterinary Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, One Shields Avenue, Davis, California 95616, USA.

Leptospirosis is reported infrequently in wild and domestic felids. We estimated the prevalence of Leptospira spp. infection and exposure using real-time PCR and serology, respectively, in 136 mountain lions (Puma concolor) and 39 bobcats (Lynx rufus) that died or were euthanized between 2009 and 2017 from several regions of California, US. Felids were classified as Leptospira-positive if they were test-positive using real-time PCR targeting the LipL32 gene of pathogenic Leptospira spp. or microscopic agglutination test for six serovars of Leptospira spp. The overall Leptospira spp. prevalence was 46% (63/136) for mountain lions and 28% (11/39) for bobcats. The most common serovar detected in both felid species was Leptospira interrogans serovar Pomona. Age class and geographic location were significantly associated with Leptospira spp. in mountain lions, but not in bobcats. Interstitial nephritis, predominately lymphocytic, was diagnosed in 39% (41/106) of mountain lions and 16% (4/25) of bobcats evaluated histologically and was significantly associated with being Leptospira spp.-positive in both species. Our findings suggest that Leptospira spp. infection is common and widespread in California's wild felids and may have clinical impacts on renal and overall health of individuals. Key words: Bobcat, Leptospira spp., leptospirosis, Lynx rufus, mountain lion, nephritis, pathology, Puma concolor.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.7589/JWD-D-20-00070DOI Listing
January 2021

USE OF FLUMETHRIN-IMPREGNATED COLLARS TO MANAGE AN EPIDEMIC OF SARCOPTIC MANGE IN AN URBAN POPULATION OF ENDANGERED SAN JOAQUIN KIT FOXES ().

J Zoo Wildl Med 2020 Nov;51(3):631-642

School of Veterinary Medicine, Department of Medicine and Epidemiology, University of California, Davis, CA 95616, USA.

Sarcoptic mange epidemics can have long-lasting impacts on susceptible wildlife populations, potentially contributing to local population declines and extirpation. Since 2013, there have been 460 reported cases of sarcoptic mange in an urban population of endangered San Joaquin kit foxes () in Bakersfield, CA, with many of them resulting in fatality. As part of a multifaceted response to mitigate mange-caused mortalities and reduce this conservation threat, a 2-yr randomized field trial was conducted to assess the efficacy of long-acting flumethrin collars against sarcoptic mange in kit foxes. Thirty-five kit foxes living in a high-density population on a college campus were captured, examined, administered selamectin, and each fox randomly assigned to either receive a flumethrin collar placed within a VHF radio collar or a VHF radio collar without flumethrin. The survival and mange-infestation status of study animals was monitored via radio telemetry, remote cameras, and periodic recapture examinations and compared among treated and control kit foxes using a Cox proportional hazards model. The average time to onset of mange for treated kit foxes (176 days) was similar to controls (171 days) and treatment with flumethrin did not significantly reduce mange risk for all kit foxes. Kit foxes that had a mild mange infestation at the beginning of the study were four times more likely to develop mange again, regardless of flumethrin treatment, compared with kit foxes that had no signs at initial recruitment. This study demonstrates an approach to evaluating population-level protection and contributes to the limited literature on efficacy, safety, and practicality of acaricides in free-ranging wildlife.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1638/2019-0197DOI Listing
November 2020

Molecular epidemiology of a fatal sarcoptic mange epidemic in endangered San Joaquin kit foxes (Vulpes macrotis mutica).

Parasit Vectors 2020 Sep 7;13(1):456. Epub 2020 Sep 7.

Department of Medicine and Epidemiology, University of California, Davis, CA, 95616, USA.

Background: In 2013, sarcoptic mange, caused by Sarcoptes scabiei mites, precipitated a catastrophic decline of the formerly stable urban population of endangered San Joaquin kit foxes (Vulpes macrotis mutica) in Bakersfield, California, USA. In 2019, a smaller sarcoptic mange outbreak affected kit foxes 58 km southwest of Bakersfield in the town of Taft, California. To determine whether the Taft outbreak could have occurred as spillover from the Bakersfield outbreak and whether epidemic control efforts must involve not only kit foxes but also sympatric dogs (Canis lupus familiaris), coyotes (Canis latrans), and red foxes (Vulpes vulpes), we evaluated genotypes and gene flow among mites collected from each host species.

Methods: We used 10 Sarcoptes microsatellite markers (SARM) to perform molecular typing of 445 S. scabiei mites collected from skin scrapings from twenty-two infested kit foxes, two dogs, five coyotes, and five red foxes from Bakersfield, Taft, and other nearby cities.

Results: We identified 60 alleles across all SARM loci; kit fox- and red fox-derived mites were relatively monomorphic, while genetic variability was greatest in Bakersfield coyote- and dog-derived mites. AMOVA analysis documented distinct mite populations unique to hosts, with an overall F of 0.467. The lowest F (i.e. closest genetic relationship, F = 0.038) was between Bakersfield and Taft kit fox-derived mites while the largest genetic difference was between Ventura coyote- and Taft kit fox-derived mites (F = 0.843).

Conclusions: These results confirm the close relationship between the Taft and Bakersfield outbreaks. Although a spillover event likely initiated the kit fox mange outbreak, mite transmission is now primarily kit fox-to-kit fox. Therefore, any large-scale population level intervention should focus on treating kit foxes within the city.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s13071-020-04328-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7487715PMC
September 2020

Assessing the role of dens in the spread, establishment and persistence of sarcoptic mange in an endangered canid.

Epidemics 2019 06 8;27:28-40. Epub 2019 Jan 8.

Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA.

Sarcoptic mange is a skin disease caused by the mite Sarcoptes scabiei that can devastate populations of wild species. S. scabiei can survive off-host and remain infective for specific periods. In den-dwelling species, dislodged mites could be protected from the environmental conditions that impair their survival thus supporting pathogen transmission. To assess the potential role of dens in the spread, establishment, and persistence of sarcoptic mange in a population of hosts, we constructed an agent-based model of the endangered San Joaquin kit fox (SJKF; Vulpes macrotis mutica) population in Bakersfield, California, that explicitly considered the denning ecology and behavior of this species. We focused on this SJKF urban population because of their vulnerability and because a sarcoptic mange epizootic is currently ongoing. Further, SJKF is a social species that lives in family groups year-round and contact between individuals from different family groups is rare, but they will occupy the same dens intermittently. If mites remain infective in dens, they could support intra-family disease transmission via direct (den sharing) and indirect (contaminated den) contact, but also inter-family transmission if susceptible individuals from different families occupy contaminated dens. Simulations showed that den-associated transmission significantly increases the chances for the mite to spread, to establish and to persist. These findings hold for different within-den S. scabiei off-host survival periods assessed. Managers dealing with S. scabiei in this species as well as in other den-dwelling species should consider den-associated transmission as they could be targeted as part of the control strategies against this mite.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.epidem.2019.01.001DOI Listing
June 2019

Hematologic and Serum Chemistry values of Endangered San Joaquin Kit Foxes ( Vulpes macrotis mutica) with Sarcoptic Mange.

J Wildl Dis 2019 04 5;55(2):410-415. Epub 2018 Oct 5.

1 University of California-Davis, School of Veterinary Medicine, Department of Medicine and Epidemiology, One Shields Avenue, Davis, California 95616, USA.

A fatal outbreak of sarcoptic mange caused by Sarcoptes scabiei in San Joaquin kit foxes ( Vulpes macrotis mutica) in Bakersfield, California, US is causing the once-stable population to decline. Given the fatality of the disease in this already-endangered species experiencing continued population declines, city-wide interventions are underway. To optimize medical management of mange-infested kit foxes, we documented serum biochemistry and hematology values for 11 kit foxes with mange collected from January-May 2015 and compared them to historical data from 18 healthy Bakersfield kit foxes. Results from kit foxes with mange were consistent with chronic illness and inflammation, protein loss, hypoglycemia, and dehydration. These findings contribute to our understanding of this debilitating, multisystemic disease that can progress to death in individuals without intervention and will aid in the treatment and care of rehabilitated individuals.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.7589/2017-10-270DOI Listing
April 2019

Comparison of Flea (Siphonaptera) Burdens on the Endangered San Joaquin Kit Fox (Vulpes macrotis mutica (Carnivora, Canidae)) Inhabiting Urban and Nonurban Environments in Central Valley, California.

J Med Entomol 2018 06;55(4):995-1001

Department of Biological Sciences, California State University Sacramento, Sacramento, CA.

The San Joaquin kit fox (Vulpes macrotis mutica Merriam (Carnivora, Canidae)) is an endangered small carnivore endemic to the San Joaquin Valley of California. Commercial and agricultural land expansion has contributed to the species' decline and invasion of more cosmopolitan species, providing means for potential ecological shifts in disease vector and host species. Fleas are common ectoparasites that can serve as important indicators of cross-species interactions and disease risk. We compared flea load and species composition on kit foxes inhabiting urban and nonurban habitats to determine how urbanization affects flea diversity and potential disease spillover from co-occurring species. We identified Echidnophaga gallinacea (Westwood) (Siphonaptera, Pulicidae) and Pulex spp. (L.) in both urban and nonurban populations, and Ctenocephalides felis (Bouche) (Siphonaptera, Pulicidae) only in the urban population. Flea load scores differed significantly across capture sites and with respect to concomitant sarcoptic mange infestation in the urban population, with milder flea infestations more typical of healthy foxes. All observed flea species are known vectors for pathogens that have been detected in mesocarnivores. Further examination of kit fox fleas and their associated pathogens will help to direct conservation and disease preventive measures for both wildlife and humans in the region.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/jme/tjy031DOI Listing
June 2018

SARCOPTIC MANGE IN ENDANGERED KIT FOXES (VULPES MACROTIS MUTICA): CASE HISTORIES, DIAGNOSES, AND IMPLICATIONS FOR CONSERVATION.

J Wildl Dis 2017 01 26;53(1):46-53. Epub 2016 Sep 26.

2   California Department of Fish and Wildlife, Wildlife Investigations Laboratory, 1701 Nimbus Road, Rancho Cordova, California 95670, USA.

The San Joaquin kit fox ( Vulpes macrotis mutica) is a federally endangered small carnivore whose distribution is limited to the San Joaquin Valley in central California. Population decline is due to profound habitat loss, and conservation of all remaining populations is critical. A robust urban population occurs in the city of Bakersfield. In spring of 2013, putative cases of mange were reported in this population. Mites from affected animals were confirmed to be Sarcoptes scabiei morphologically and by DNA sequencing. By the end of 2014, 15 cases of kit foxes with mange had been confirmed. As with other species, sarcoptic mange in kit foxes is characterized by intense pruritus and dermatitis, caused by mites burrowing into the epidermal layers, as well as alopecia, hyperkeratosis, and encrustations, secondary bacterial infections, and finally extreme morbidity and death. Of the 15 cases, six foxes were found dead, six were captured but died during attempted rehabilitation, and three were successfully treated. We have no evidence that untreated kit foxes can recover from mange. Sarcoptic mange constitutes a significant threat to the Bakersfield kit fox population and could pose an even greater threat to this imperiled species if it spreads to populations in nearby natural lands.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.7589/2016-05-098DOI Listing
January 2017

Serum chemistry, hematologic, and post-mortem findings in free-ranging bobcats (Lynx rufus) with notoedric mange.

J Parasitol 2013 Dec 19;99(6):989-96. Epub 2013 Aug 19.

Department of Ecology and Evolutionary Biology, University of California, Los Angeles, California 90095.

Notoedric mange was responsible for a population decline of bobcats ( Lynx rufus ) in 2 Southern California counties from 2002-2006 and is now reported to affect bobcats in Northern and Southern California. With this study we document clinical laboratory and necropsy findings for bobcats with mange. Bobcats in this study included free-ranging bobcats with mange (n = 34), a control group of free-ranging bobcats without mange (n = 11), and a captive control group of bobcats without mange (n = 19). We used 2 control groups to evaluate potential anomalies due to capture stress or diet. Free-ranging healthy and mange-infected bobcats were trapped or salvaged. Animals were tested by serum biochemistry, complete blood count, urine protein and creatinine, body weight, necropsy, and assessment for anticoagulant rodenticide residues in liver tissue. Bobcats with severe mange were emaciated, dehydrated, and anemic with low serum creatinine, hyperphosphatemia, hypoglycemia, hypernatremia, and hyperchloremia, and sometimes septicemic when compared to control groups. Liver enzymes and leukocyte counts were elevated in free-ranging, recently captured bobcats whether or not they were infested with mange, suggesting capture stress. Bobcats with mange had lower levels of serum cholesterol, albumin, globulin, and total protein due to protein loss likely secondary to severe dermatopathy. Renal insufficiency was unlikely in most cases, as urine protein:creatinine ratios were within normal limits. A primary gastrointestinal loss of protein or blood was possible in a few cases, as evidenced by elevated blood urea nitrogen, anemia, intestinal parasitism, colitis, gastric hemorrhage, and melena. The prevalence of exposure to anticoagulant rodenticides was 100% (n = 15) in bobcats with mange. These findings paint a picture of debilitating, multisystemic disease with infectious and toxic contributing factors that can progress to death in individuals and potential decline in populations.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1645/12-175.1DOI Listing
December 2013
-->