ecology Archives - Prairie Dog Pals

A Novel Retrovirus (Gunnison’s Prairie Dog Retrovirus) Associated With Thymic Lymphoma in Gunnison’s Prairie Dogs in Colorado, USA

June 8, 2020 by PDP

Abstract

As part of research and wildlife disease surveillance efforts, we performed necropsy examinations of 125 free-ranging (n = 114) and captive (n = 11) prairie dogs in Colorado from 2009 to 2017. From these cases, we identified three cases of thymic lymphoma in free-ranging Gunnison’s prairie dogs (Cynomys gunnisoni), and we identified a novel retroviral sequence associated with these tumors. The viral sequence is 7700 nucleotides in length and exhibits a genetic organization that is consistent with the characteristics of a type D betaretrovirus. The proposed name of this virus is Gunnison’s prairie dog retrovirus (GPDRV). We screened all 125 prairie dogs for the presence of GPDRV using PCR with envelope-specific primers and DNA extracted from spleen samples. Samples were from Gunnison’s prairie dogs (n = 59), black-tailed prairie dogs (Cynomys ludovicianus) (n = 40), and white-tailed prairie dogs (Cynomys leucurus) (n = 26). We identified GPDRV in a total of 7/125 (5.6%) samples including all three of the prairie dogs with thymic lymphoma, as well as spleen from an additional four Gunnison’s prairie dogs with no tumors recognized at necropsy. None of the GPDRV-negative Gunnison’s prairie dogs had thymic lymphomas. We also identified a related, apparently endogenous retroviral sequence in all prairie dog samples. These results suggest that GPDRV infection may lead to development of thymic lymphoma in Gunnison’s prairie dogs.

Molly D Butler¹, Karen Griffin², Connie D Brewster¹, Marylee L Kapuscinski¹, Mark D Stenglein¹, Daniel W Tripp², Sandra L Quackenbush¹, Karen A Fox²

Affiliations

PMID: 32498297
DOI: 10.3390/v12060606

Am J Vet Res. 2019 Dec;80(12):1114-1121. doi: 10.2460/ajvr.80.12.1114. Comparison of the effects of a dexmedetomidine-ketamine-midazolam anesthetic protocol versus isoflurane inhalation anesthesia on echocardiography variables and plasma cardiac troponin I concentration in black-tailed prairie dogs (Cynomys ludovicianus).

December 7, 2019 by PDP

Ross E, Thomason JD, Browning GR, Beaufrère H, Eshar D.

Abstract

OBJECTIVE:

To compare the effects of a dexmedetomidine-ketamine-midazolam (DKM) anesthetic protocol versus isoflurane inhalation anesthesia on echocardiographic variables and plasma cardiac troponin 1 (cTnI) concentration in black-tailed prairie dogs (BTPDs; Cynomys ludovicianus)

ANIMALS:

Nine 6-month-old sexually intact male captive BTPDs.

PROCEDURES:

Each BTPD was randomly assigned to be anesthetized by IM administration of dexmedetomidine (0.25 mg/kg), ketamine (40 mg/kg), and midazolam (1.5 mg/kg) or via inhalation of isoflurane and oxygen. Three days later, each BTPD underwent the alternative anesthetic protocol. Echocardiographic data and a blood sample were collected within 5 minutes after initiation and just prior to cessation of each 45-minute-long anesthetic episode.

RESULTS:

Time or anesthetic protocol had no significant effect on echocardiographic variables. For either protocol, plasma cTnI concentration did not differ with time. When administered as the first treatment, neither anesthetic protocol significantly affected plasma cTnI concentration. However, with regard to findings for the second treatments, plasma cTnI concentrations in isoflurane-treated BTPDs (n = 4; data for 1 animal were not analyzed because of procedural problems) were higher than values in DKM-treated BTPDs (4), which was suspected to be a carryover effect from prior DKM treatment.

CONCLUSIONS AND CLINICAL RELEVANCE:

The DKM and isoflurane anesthetic protocols did not have any significant effect on echocardiographic measurements in the BTPDs. Increases in plasma cTnI concentration during the second anesthetic episode were evident when BTPDs underwent the DKM anesthetic protocol as the first of the 2 treatments, suggestive of potential myocardial injury associated with that anesthetic protocol. Clinicians should consider these findings, especially when evaluating BTPDs with known or suspected cardiac disease.

PMID: 31763940

Amyloid-producing Odontoameloblastoma in a Black-tailed Prairie Dog (Cynomys ludovicianus)

September 10, 2018 by PDP

A 6-year-old female black-tailed prairie dog (Cynomys ludovicianus) was presented with a space-occupying lesion in the left submandibular region. On computed tomography, a low attenuating, poorly circumscribed mass infiltrated the left mandibular bone, with osteolytic change. Microscopically, the lesion was composed of odontogenic epithelium proliferating in nests and embedded in abundant dental papilla-like ectomesenchyme, including dentine and enamel. Multifocal amyloid deposition was observed. Immunohistochemically, the neoplastic epithelial cells were positive for cytokeratin (CK) AE1/AE3, CK14 and p63. Some epithelial cells were positive for amelogenin and some adjacent to the amyloid deposits co-expressed S100. The ectomesenchymal cells expressed vimentin and strong S100 immunoreactivity was observed in odontoblast-like cells. The amyloid was immunolabelled with amelogenin. The tumour was diagnosed as amyloid-producing odontoameloblastoma.

Medieval diseases are making a grim comeback

October 21, 2017 by PDP

The Black Death was little short of a bacterial apocalypse. The outbreak of bubonic plague, imported along the Silk Road, is thought to have killed between 25m and 50m people as it rampaged through 14th-century Europe. The disease thence resurfaced sporadically: the Great Plague of London, for example, felled a fifth of city dwellers in the 1660s.

While the plague seems to us a medieval affliction, it has never fully disappeared. On average, about 500 cases are documented globally each year, mostly in Africa, South America and India. The infection is treatable with antibiotics if caught early.

Duggan: Prairie dogs score a victory in Fort Collins

February 10, 2017 by PDP

Prairie dogs have scored a victory in Fort Collins, or at least their advocates have.

The City Council on Tuesday gave initial approval to a set of changes to the city’s Land Use Code aimed at giving prairie dogs more protection from development than they have enjoyed during the last 20 years.