DICTYOCAULUS CERVI-LIKE LUNGWORM INFECTION IN A ROCKY MOUNTAIN ELK (CERVUS CANADENSIS NELSONI) FROM WYOMING, USA.

Dictyocaulus spp. infections are common in North American cervids, with Dictyocaulus viviparus described as most common. A Rocky Mountain elk (Cervus canadensis nelsoni) was found dead in Wyoming, US with significant bronchitis and pneumonia. In the bronchi and trachea, numerous large nematodes were found and grossly identified as Dictyocaulus spp. lungworms. Macroscopic alterations, such as distended interlobular septa and edema with foam and mucus observed on cut surface and in trachea and bronchi, were consistent with those commonly described in D. viviparus infections. Female lungworms were identified to Dictyocaulus spp. level via morphologic examination and molecular analyses based on mitochondrial cyclooxygenase 1 and 18S ribosomal RNA genes. A phylogenetic analysis was conducted employing the maximum likelihood method. Based on both morphologic and genetic assays, the isolated lungworms were most likely a strain of Dictyocaulus cervi. Within the female adult worms, free first stage larvae were observed besides worm eggs, which had not been described for Dictyocaulus spp. Phylogenetic analysis revealed that our parasites clustered closely with D. cervi, forming a subclade with that species within a larger clade that includes Dictyocaulus eckerti. While the elk tested positive for chronic wasting disease, it is assumed that significant pathology in the present case was caused directly by infection with the D. cervi-like lungworm, not previously described in North America.

Infectious keratoconjunctivitis in free-ranging mule deer in Wyoming: a retrospective study and identification of a novel alphaherpesvirus.

We describe the clinicopathologic findings, relative prevalence, and pathogens associated with infectious keratoconjunctivitis in mule deer ( Odocoileus hemionus) in Wyoming. Seventeen cases with ocular lesions were identified among 1,036 mule deer postmortem submissions (1.6%) in an ~16 y period. Sixteen cases were observed in winter and most were in male (15 cases) and juvenile (13 cases) deer. Blindness was the most commonly reported clinical sign (10 cases). A herpesvirus was detected only in the 4 cases of bilateral necrotizing bulbar conjunctivitis. Phylogenetic analysis of glycoprotein amino acid sequences consistently identified this virus as a novel alphaherpesvirus. In 2 of these herpesvirus-positive cases, Actinomyces sp. and Moraxella ovis were also identified. Trueperella pyogenes was identified in 4 cases of unilateral ulcerative keratitis, keratoconjunctivitis, and panophthalmitis. M. ovis was cultured from 3 cases of bilateral conjunctivitis and keratoconjunctivitis. In the remaining cases, isolates included Moraxella bovis (1 case), Staphylococcus sp. and Streptococcus sp. (2), Flavobacterium sp. and Pseudomonas sp. (2), Escherichia coli and Enterobacter sp. (1), and bovine viral diarrhea virus 1 (1). No pathogens were identified in 2 cases. The relative prevalence of keratoconjunctivitis in mule deer in Wyoming appears to be low, and this disease is most commonly associated with infection by a novel alphaherpesvirus, T. pyogenes, and M. ovis.

Whole-genome sequences of Odocoileus hemionus deer adenovirus isolates from deer, moose and elk are highly conserved and support a new species in the genus Atadenovirus.

We present the first complete genome sequence of Odocoileus hemionus deer adenovirus 1 (OdAdV-1). This virus can cause sporadic haemorrhagic disease in cervids, although epizootics with high mortality have occurred in California. OdAdV-1 has been placed in the genus Atadenovirus, based on partial hexon, pVIII and fibre genes. Ten field isolates recovered from naturally infected mule deer (Odocoileus hemionus), white-tailed deer (Odocoileus virginiana) and moose (Alces alces) from Wyoming, black-tailed deer (Odocoileus hemionus columbianus) from California, and Rocky Mountain elk (Cervus elaphus nelsoni) from Colorado and Washington state were sequenced. The genome lengths ranged from 30 620 to 30 699 bp, contained the predicted proteins and gene organization typical of members of genus Atadenovirus, and had a high percentage of A/T nucleotides (66.7 %). Phylogenic analysis found that the closest ancestry was with ruminant atadenoviruses, while a divergence of the hexon, polymerase and penton base proteins of more than 15 % supports classification as a new species. Genetic global comparison between the 10 isolates found an overall 99 % identity, but greater divergence was found between those recovered from moose and elk as compared to deer, and a single variable region contained most of these differences. Our findings demonstrate that OdAdV-1 is highly conserved between 10 isolates recovered from multiple related cervid species, but genotypic differences, largely localized to a variable region, define two strains. We propose that the virus type name be changed to cervid adenovirus 1, with the species name Cervid atadenovirus A. Sequence data were used to develop molecular assays for improved detection and genotyping.

A baiting system for delivery of an oral plague vaccine to black-tailed prairie dogs.

Laboratory and field studies were conducted between July and October 1999 to identify bait preference, biomarker efficacy, and bait acceptance rates for delivering an oral plague vaccine to black-tailed prairie dogs (Cynomys ludovicianus). Twenty juvenile captive prairie dogs were offered alfalfa baits containing either alfalfa, alfalfa and 5% molasses, or alfalfa, 5% molasses and 4% salt. Based on the results of these trials we selected a bait containing alfalfa, 7% molasses, and 1% salt for field trials to determine bait acceptance rates by free-ranging animals. The biomarkers DuPont Blue dye, iophenoxic acid, and tetracycline hydrochloride were orally administered to captive prairie dogs to determine their efficacy. Only tetracycline proved effective as a biomarker. Two field trials were conducted at separate prairie dog colonies located at the Buffalo Gap National Grassland (Pennington County, South Dakota, USA). In Trial 1, three baits containing tetracycline were distributed around each active burrow entrance and an additional bait was placed inside the burrow (1,276 baits total). In Trial 2, baits were distributed at the same density per burrow as Trial 1, but along transects spaced 10 m apart (1,744 baits total). Trapping began 3 days after bait distribution, and 30 prairie dogs then were captured at each site to determine the percentage of animals marked. In Trial 1, 67% of the prairie dogs captured had tetracycline deposits indicative of bait consumption. In Trial 2, 83% of the prairie dogs had ingested a bait. Approximately 15% of the animals in both trials ate more than one bait. Fleas (Opisocrostis hirsutus) were found on 64 of 70 (91%) of the prairie dogs captured during this study.