Compressive myelopathy due to intervertebral disk extrusion in a llama (Lama glama).

A 12-year-old intact female llama was euthanized following acute onset of spastic tetraparesis and recumbency with inability to rise. Postmortem examination revealed caudal cervical spinal cord compression due to a mass within the ventral spinal canal arising from the C6-C7 intervertebral disk space and attached to an irregularly thickened annulus fibrosis. On histopathologic examination, the mass was composed of amorphous acellular basophilic to amphophilic material admixed with irregularly arranged collagen bundles. The amorphous material was metachromatic and contained multiple small foci of markedly vacuolated round cells, characteristic of origin from the nucleus pulposus. Severe necrosis of all white matter tracts with astrocytic reaction was present in the overlying spinal cord segment. Ascending and descending Wallerian degeneration and dissecting interstitial astrogliosis were present within white matter tracts above and below the lesion, respectively. The diagnosis was compressive myelopathy due to chronic extrusion of the nucleus pulposus of the C6-C7 intervertebral disk. To the authors' knowledge, this is the first report of intervertebral disk disease in a camelid.     

Survey of equine cutaneous neoplasia in the Pacific Northwest.

A retrospective study examined data regarding equine cutaneous and mucocutaneous neoplasms submitted to the Veterinary Diagnostic Laboratory at Oregon State University in a 3.5-year period. A total of 536 neoplasms were identified, accounting for 30% of the total equine pathology submissions. Sarcoid, squamous cell carcinoma, melanocytic tumors, papillomas, and mast cell tumors were the most common neoplasms, constituting 87.5% of all cutaneous neoplasms. Sarcoids represented 51.4% of all neoplasms and 15.18% of total equine accessions. Sarcoid was most common in paints, quarter horses, and Arabians, and was the only common tumor in donkeys and mules. Mean age at diagnosis of equine sarcoid was 9 years. Squamous cell carcinoma constituted 18.3% of all neoplasms and 5.41% of total equine accessions. Ocular squamous cell carcinoma was most common in paints and quarter horses, and penile/preputial squamous cell carcinoma was most common in appaloosas and quarter horses. The mean age of horses with ocular squamous cell carcinoma (13 years) and squamous cell carcinoma of the skin (15 years) was significantly less (P < 0.5) than that of horses with squamous cell carcinoma of the penis and prepuce (21 years) or vulva, anal, and perianal skin (19 years). Findings suggest that equine sarcoid and squamous cell carcinoma occur more frequently in the Pacific Northwest than in the northeastern United States.     

Prevalence of neoplasia in llamas and alpacas (Oregon State University, 2001-2006).

Prevalence and type of neoplastic disease were determined in 551 camelid submissions (368 alpacas [Lama pacos], 180 llamas [Lama glama], and 3 cases in which species was not identified) over a 5-year period. Forty neoplasms were identified in 38 animals (6.9%). Prevalence of neoplasia in llamas was higher (11%) than in alpacas (4.9%). Mean age of camelids with neoplasia was 9.42 +/- 4.9 years. Mean age of alpacas with neoplasia (5.48 +/- 3.7 years) was significantly less than of llamas with neoplasia (12.53 +/- 3.2 years; P < 0.001). Cutaneous and mucocutaneous fibroma/fibropapilloma was most common (10 animals), followed by cutaneous and mucocutaneous squamous cell carcinoma (6 animals), disseminated lymphoma (5 animals), and fibrosarcoma (4 animals). Four of 5 animals with lymphoma were alpacas, aged 0.21 to 4 years. Lymphoma occurred in 1 aged llama (15 years). Disseminated carcinoma and adenocarcinoma occurred in 4 llamas and 2 alpacas, and included biliary (2), gastrointestinal (2), mammary gland (1), and unknown (1) origin. Mean age of camelids with any type of carcinoma or adenocarcinoma (12.36 +/- 2.8 years) was significantly greater than that of camelids with lymphoma (4.24 +/- 6.2 years; P = 0.02). Results indicate that neoplasia is relatively common in camelids and that there are differences between llamas and alpacas as regards prevalence of neoplasia, tumor types, and age at diagnosis.     

Muscular pseudohypertrophy (steatosis) in a bovine fetus.

Muscular pseudohypertrophy was diagnosed in the cervical musculature of a full-term crossbred Simmental fetus delivered by fetotomy. Only head and cervical regions were submitted for pathologic examination; the rest of the fetal body was reportedly normal. The neck musculature of the fetus was markedly deformed by 23 cm and 18 cm in diameter, firm, spherical masses that consisted of enlarged and pale left splenius and right serratus ventralis cervicis muscle, respectively, covered by intact skin. Additionally, lipomatous masses were present within the cervical vertebral canal, compressing the spinal cord. Microscopically, the prominent muscular enlargement was due to massive adipose and fibrous connective tissue replacement of atrophic muscle. Focal myelodysplasia and astrocytosis affecting the grey matter was detected in the mid-cervical region of the spinal cord, accompanied by degeneration in the ascending and descending tracts of the remaining cord segments. Abnormal spinal cord development as a result of severe spinal cord compression by the lipomatous masses within the spinal canal leading to replacement of muscle by fat and fibrous tissue was considered to be the cause of the muscular malformation in this fetus.     

Landscape characteristics of <Emphasis Type="Italic">Rhizophora mangle</Emphasis> forests and propagule deposition in coastal environments of Florida (USA)

Field dispersal studies are seldom conducted at regional scales even though reliable information on mid-range dispersal distance is essential for models of colonization. The purpose of this study was to examine the potential distance of dispersal of Rhizophora mangle propagules by comparing deposition density with landscape characteristics of mangrove forests. Propagule density was estimated at various distances to mangrove sources (R. mangle) on beaches in southwestern Florida in both high-and low-energy environments, either facing open gulf waters vs. sheltered, respectively. Remote sensing and Geographic Information Systems were used to identify source forests and to determine their landscape characteristics (forest size and distance to deposition area) for the regression analyses. Our results indicated that increasing density of propagules stranded on beaches was related negatively to the distance of the deposition sites from the nearest stands of R. mangle and that deposition was greatly diminished 2 km or more from the source. Measures of fragmentation such as the area of the R. mangle forests were related to propagule deposition but only in low-energy environments. Our results suggest that geographic models involving the colonization of coastal mangrove systems should include dispersal dynamics at mid-range scales, i.e., for our purposes here, beyond the local scale of the forest and up to 5 km distant. Studies of mangrove propagule deposition at various spatial scales are key to understanding regeneration limitations in natural gaps and restoration areas. Therefore, our study of mid-range propagule dispersal has broad application to plant ecology, restoration, and modeling.     

Efficacy and toxicity of a dose-intensified doxorubicin protocol in canine hemangiosarcoma

The purpose of this study was to evaluate the efficacy and toxicity of a single-agent, dose-intensified doxorubicin protocol in canine hemangiosarcoma (HSA). Canine HSA is a highly malignant tumor, and most affected dogs die within 6 months of diagnosis. Doxorubicin is the most, and possibly the only, effective chemotherapeutic drug for this malignancy, but it provides only moderate improvement in survival. On the basis of previous studies reporting similar survival in dogs treated with doxorubicin as a single agent and doxorubicin-based combination chemotherapy and the concept of summation dose intensity, a dose-intensified single-agent doxorubicin protocol was initiated. Twenty dogs with HSA were recruited to participate in this study. Workup and staging were performed according to standard practice. Chemotherapy was initiated within 3 weeks of surgery. Doxorubicin was scheduled to be administered at 30 mg/m2 i.v. every 2 weeks for a total of 5 treatments. The dogs were monitored for toxicity and signs of recurrence during and at regular intervals after chemotherapy. The protocol was tolerated well. No dogs were hospitalized because of adverse effects or developed clinical signs consistent with doxorubicin-induced cardiomyopathy. There was a significant difference in survival in dogs with stage I and I1 HSA compared with dogs with stage III HSA. with median survival times of 257, 210, and 107 days, respectively. These results are slightly better than the historical control with respect to toxicity and efficacy but are not statistically different from what is achieved with standard treatments. There was no association between dose intensity and outcome.     

Equine congenital papilloma: pathological findings and results of papillomavirus immunohistochemistry in five cases

Abstract Congenital cutaneous papillomas were identified in five foals. Age at diagnosis ranged from 305 days' gestation to 2 days of age. Breeds were thoroughbred (2), standard-bred (1), warmblood (1) and paint (1). Two were female, one was male and the gender of two cases was not specified. Masses were pedunculated with a roughened, wart-like (verrucous) or a smoother, cauliflower-like surface. Masses occurred as single lesions on the forelimb, lip and face, or as multiple lesions on the trunk. Histological features included relatively uniform epidermal papillary hyperplasia with variable melanin pigment within basal layers and vacuolization of keratinocytes in all layers, but with no evidence of nuclear or cytoplasmic changes (koilocytes) characteristic of viral infection. One case showed epidermal proliferation with proliferation of pilosebaceous units. Results of immunohistochemical studies for the detection of papillomavirus antigens were negative in all cases. These results suggest that equine congenital papilloma may be a hamartomatous lesion (epidermal nevus) and not a viral-induced growth.     

“Si no comemos tortilla,no vivimos:” women,climate change,and food security in central Mexico

In recent years, it has become clear that food security is intimately related to complex environmental, social, political, and economic issues. Even though several studies document the impact of climate on food production and agriculture, a growing segment of research examines how climate change impacts food systems and associated livelihoods. Furthermore, while women play a crucial role in providing food security for their families, little research exists that examines the nexus among gender relations, climate change, and household food security. This study investigates these relationships by asking: (1) how is the production and reproduction of knowledge about food security and climate change shaped by gender and lived experience, and (2) how does this knowledge influence attitudes and strategies for maintaining food security in a changing climate? Drawing on the results of research in two communities in central Mexico, I argue that women’s perceptions of and strategies for maintaining food security are derived from their socio-political, environmental, and economic contexts. This study contributes to both the growing literature on the gender dynamics of climate change, as well as debates about the role of bioengineered seeds in helping farmers to adapt to a changing climate.     

The importance of localized culling in stabilizing chronic wasting disease prevalence in white-tailed deer populations

Strategies to contain the spread of disease often are developed with incomplete knowledge of the possible outcomes but are intended to minimize the risks associated with delaying control. Culling of game species by government agencies is one approach to control disease in wild populations but is unpopular with hunters and wildlife enthusiasts, politically unpalatable, and erodes public support for agencies responsible for wildlife management. We addressed the functional differences between hunting and government culling programs for managing chronic wasting disease (CWD) in white-tailed deer by comparing prevalence over a 10-year period in Illinois and Wisconsin. When both Illinois and Wisconsin were actively culling from 2003 – 2007, there were no statistical differences between state CWD prevalence estimates. Wisconsin government culling concluded in 2007 and average prevalence over the next five years was 3.09 ± 1.13% with an average annual increase of 0.63%. During that same time period, Illinois continued government culling and there was no change in prevalence throughout Illinois. Despite its unpopularity among hunters, localized culling is a disease management strategy that can maintain low disease prevalence while minimizing impacts on recreational deer harvest.     

Evaluation of ELISA coupled with Western blot as a surveillance tool for Trichinella infection in wild boar (Sus scrofa)

Trichinella surveillance in wildlife relies on muscle digestion of large samples which are logistically difficult to store and transport in remote and tropical regions as well as labour-intensive to process. Serological methods such as enzyme-linked immunosorbent assays (ELISAs) offer rapid, cost-effective alternatives for surveillance but should be paired with additional tests because of the high false-positive rates encountered in wildlife. We investigated the utility of ELISAs coupled with Western blot (WB) in providing evidence of Trichinella exposure or infection in wild boar. Serum samples were collected from 673 wild boar from a high- and low-risk region for Trichinella introduction within mainland Australia, which is considered Trichinella-free. Sera were examined using both an ‘in-house’ and a commercially available indirect-ELISA that used excretory–secretory (E/S) antigens. Cut-off values for positive results were determined using sera from the low-risk population. All wild boar from the high-risk region (352) and 139/321 (43.3%) of the wild boar from the low-risk region were tested by artificial digestion. Testing by Western blot using E/S antigens, and a Trichinella-specific real-time PCR was also carried out on all ELISA-positive samples. The two ELISAs correctly classified all positive controls as well as one naturally infected wild boar from Gabba Island in the Torres Strait. In both the high- and low-risk populations, the ELISA results showed substantial agreement (k-value = 0.66) that increased to very good (k-value = 0.82) when WB-positive only samples were compared. The results of testing sera collected from the Australian mainland showed the Trichinella seroprevalence was 3.5% (95% C.I. 0.0–8.0) and 2.3% (95% C.I. 0.0–5.6) using the in-house and commercial ELISA coupled with WB respectively. These estimates were significantly higher (P < 0.05) than the artificial digestion estimate of 0.0% (95% C.I. 0.0–1.1). Real-time PCR testing of muscle from seropositive animals did not detect Trichinella DNA in any mainland animals, but did reveal the presence of a second larvae-positive wild boar on Gabba Island, supporting its utility as an alternative, highly sensitive method in muscle examination. The serology results suggest Australian wildlife may have been exposed to Trichinella parasites. However, because of the possibility of non-specific reactions with other parasitic infections, more work using well-defined cohorts of positive and negative samples is required. Even if the specificity of the ELISAs is proven to be low, their ability to correctly classify the small number of true positive sera in this study indicates utility in screening wild boar populations for reactive sera which can be followed up with additional testing.