Denver, CO, United States
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Shipley B.K.,Denver Zoological Gardens | Chiszar D.,University of Colorado at Boulder | Fitzgerald K.T.,Alameda East Veterinary Hospital | Saviola A.J.,University of Northern Colorado
Herpetological Conservation and Biology | Year: 2013

We analyzed movements of three groups of radio-telemetered Prairie Rattlesnakes (Crotalus viridis) hibernating in three Black-tailed Prairie Dog (Cynomys ludovicianus) colonies within short-grass prairie in Arapahoe County, Colorado. Movements were short and frequent, with mean R values (measuring straightness-of-path) not exceeding 0.6. Mean total distance traveled during the entire active season was 3007 m. On average, snakes moved 0.7 times per day, traveling 89 m per movement. Home range sizes varied from 0.3-31.4 ha. All snakes returned in autumn to the same colony in which they hibernated the previous winter. Increased foraging opportunities in our study site may have supported shorter migrations than have been reported for C viridis in Wyoming. Greater body mass of our rattlesnakes and a Nebraska population of C viridis relative to a Wyoming population of C viridis indirectly supports this idea. We discuss conservation implications of these findings. © 2013. Bryon Shipley. All Rights Reserved.


Gyimesi Z.S.,Louisville Zoological Garden | Burns R.B.,Louisville Zoological Garden | Campbell M.,Cincinnati Zoo and Botanical Garden | Knightly F.,Denver Zoological Gardens | And 4 more authors.
Journal of Zoo and Wildlife Medicine | Year: 2011

Fatal abomasal impaction, often combined with omasal impaction, was diagnosed in 11 bongo (Tragelaphus eurycerus) from five different zoologic collections in the United States between 1981 and 2009. Nine of 11 cases occurred in young females (10 mo-7 yr old) and typical clinical signs prior to diagnosis or death included partial or complete anorexia, dehydration, and scant fecal production. Although the clinical histories in several of the earlier cases are incomplete, clinical signs were known to begin shortly after an anesthetic event in five of 11 bongo (45%). Pedigree analysis indicates that affected bongo were descendants of multiple founders and not from a single family line, suggesting that the development of abomasal impaction is not a strictly inheritable trait. Treatment, when attempted, was variable and included abomasotomy and removal of impacted ingesta, drug therapy (prokinetic drugs, nonsteroidal anti-inflammatories, antimicrobials), fluid therapy, and administration of oral lubricants or intralesional stool softeners. Based on the outcomes in the cases presented here, the prognosis for bongo with abomasal impaction is considered poor to grave. Copyright 2011 by American Association of Zoo Veterinarians.


Fitzgerald K.T.,VCA Alameda East Veterinary Hospital | Shipley B.K.,Denver Zoological Gardens | Newquist K.L.,VCA Alameda East Veterinary Hospital | Vera R.,VCA Firehouse Veterinary Hospital | Flood A.A.,VCA Alameda East Veterinary Hospital
Topics in Companion Animal Medicine | Year: 2013

On account of their unique anatomy, physiology, natural history, ecology, and behavior, rattlesnakes make ideal subjects for a variety of different scientific disciplines. The prairie rattlesnake (Crotalus viridis) in Colorado was selected for investigation of its relationship to colonies of black-tailed prairie dogs (Cynomys ludovicianus) with regard to spatial ecology. A total of 31 snakes were anesthetized and had radiotransmitters surgically implanted. In addition, at the time of their capture, all snakes underwent the following: (1) they had bacterial culture taken from their mouths for potential isolation of pathogenic bacteria; (2) similarly, they had cloacal bacterial cultures taken to assess potentially harmful bacteria passed in the feces; and (3) they had blood samples drawn to investigate the presence of any zoonotic agents in the serum of the snakes. The results of the study and their implications are discussed here. Traditionally, a low incidence of bacterial wound infection has been reported following snakebite. Nevertheless, the oral cavity of snakes has long been known to house a wide variety of bacterial flora. In our study, 10 different bacterial species were isolated from the mouths of the rattlesnakes, 6 of which are capable of being zoonotic pathogens and inducing human disease. More studies are necessary to see why more rattlesnake bites do not become infected despite the presence of such pathogenic bacteria. The results of fecal bacteria isolated revealed 13 bacterial species, 12 of which can cause disease in humans. Of the snakes whose samples were cultured, 26% were positive for the presence of the pathogen Salmonella arizonae, one of the causative agents of reptile-related salmonellosis in humans. It has long been reported that captive reptiles have a much higher incidence than wild, free-ranging species. This study shows the incidence of Salmonella in a wild, free-ranging population of rattlesnakes. In addition, Stenotrophomonas maltophilia was isolated. This bacterium is associated with wound and soft tissue infections that can lead to sepsis, endocarditis, meningitis, and peritonitis. In addition, this bacterium has been increasingly implicated as an opportunistic pathogen to humans during pregnancies, hospitalizations, malignancies and chemotherapy, chronic respiratory diseases, and presurgical endotracheal intubation. Furthermore, S. maltophilia has an intense resistance to broad-spectrum antibiotics, the results of our study showed the bacterium was resistant to multiple antibiotics. Our results indicate that anyone working with snake feces, dead skin, or their carcasses must follow reasonable hygiene protocols. Rattlesnakes tested for West Nile antibodies had positive results but these were invalidated owing to possible cross-reactivity with other unknown viruses, interference with snake serum proteins, and the fact that the test was not calibrated for rattlesnake serum. Still, the interesting implication remains, should we be regularly testing these animals as sentinels against potentially zoonotic diseases. The results of this study clearly show the value of veterinarians in a multidisciplinary study of this sort and the particular skill set they can offer. Veterinarians must get involved in conservation studies if the biodiversity of the planet is to be preserved. © 2013.


PubMed | VCA Firehouse Veterinary Hospital, VCA Alameda East Veterinary Hospital and Denver Zoological Gardens
Type: Journal Article | Journal: Topics in companion animal medicine | Year: 2013

On account of their unique anatomy, physiology, natural history, ecology, and behavior, rattlesnakes make ideal subjects for a variety of different scientific disciplines. The prairie rattlesnake (Crotalus viridis) in Colorado was selected for investigation of its relationship to colonies of black-tailed prairie dogs (Cynomys ludovicianus) with regard to spatial ecology. A total of 31 snakes were anesthetized and had radiotransmitters surgically implanted. In addition, at the time of their capture, all snakes underwent the following: (1) they had bacterial culture taken from their mouths for potential isolation of pathogenic bacteria; (2) similarly, they had cloacal bacterial cultures taken to assess potentially harmful bacteria passed in the feces; and (3) they had blood samples drawn to investigate the presence of any zoonotic agents in the serum of the snakes. The results of the study and their implications are discussed here. Traditionally, a low incidence of bacterial wound infection has been reported following snakebite. Nevertheless, the oral cavity of snakes has long been known to house a wide variety of bacterial flora. In our study, 10 different bacterial species were isolated from the mouths of the rattlesnakes, 6 of which are capable of being zoonotic pathogens and inducing human disease. More studies are necessary to see why more rattlesnake bites do not become infected despite the presence of such pathogenic bacteria. The results of fecal bacteria isolated revealed 13 bacterial species, 12 of which can cause disease in humans. Of the snakes whose samples were cultured, 26% were positive for the presence of the pathogen Salmonella arizonae, one of the causative agents of reptile-related salmonellosis in humans. It has long been reported that captive reptiles have a much higher incidence than wild, free-ranging species. This study shows the incidence of Salmonella in a wild, free-ranging population of rattlesnakes. In addition, Stenotrophomonas maltophilia was isolated. This bacterium is associated with wound and soft tissue infections that can lead to sepsis, endocarditis, meningitis, and peritonitis. In addition, this bacterium has been increasingly implicated as an opportunistic pathogen to humans during pregnancies, hospitalizations, malignancies and chemotherapy, chronic respiratory diseases, and presurgical endotracheal intubation. Furthermore, S. maltophilia has an intense resistance to broad-spectrum antibiotics, the results of our study showed the bacterium was resistant to multiple antibiotics. Our results indicate that anyone working with snake feces, dead skin, or their carcasses must follow reasonable hygiene protocols. Rattlesnakes tested for West Nile antibodies had positive results but these were invalidated owing to possible cross-reactivity with other unknown viruses, interference with snake serum proteins, and the fact that the test was not calibrated for rattlesnake serum. Still, the interesting implication remains, should we be regularly testing these animals as sentinels against potentially zoonotic diseases. The results of this study clearly show the value of veterinarians in a multidisciplinary study of this sort and the particular skill set they can offer. Veterinarians must get involved in conservation studies if the biodiversity of the planet is to be preserved.


Valkiunas G.,Nature Research Center | Mobley K.,Denver Zoological Gardens | Iezhova T.A.,Nature Research Center
Parasitology Research | Year: 2016

Blood parasites of the genus Hepatozoon (Apicomplexa, Hepatozoidae) infect all groups of terrestrial vertebrates, and particularly high prevalence and species diversity have been reported in reptiles and mammals. A few morphologically similar species, in which gamonts inhabit mononuclear leukocytes and red blood cells, have been described in birds. Here, we report a new Hepatozoon species, which was found in wild-caught secretary birds Sagittarius serpentarius, from Tanzania. Hepatozoon ellisgreineri n. sp. can be readily distinguished from all described species of avian Hepatozoon because its gamonts develop only in granulocytes, predominantly in heterophils, a unique characteristic among bird parasites of this genus. Additionally, this is the first reported avian apicomplexan blood parasite, which inhabits and matures in granulocytes. We describe H. ellisgreineri based on morphological characteristics of blood stages and their host cells. This finding broadens knowledge about host cells of avian Hepatozoon spp. and other avian apicomplexan blood parasites, contributing to the better understanding of the diversity of haematozoa. This is the first report of hepatozoonosis in endangered African birds of the Sagittariidae. © 2015, Springer-Verlag Berlin Heidelberg.

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