A survey of the selenium status of beef cows in Alberta.

An epidemiological survey was conducted in Alberta to measure the selenium status in blood of beef cows during the fall and to determine the risk of selenium deficiency among specific geographic regions of Alberta. Three census divisions of Alberta based on the Statistics Canada Census of Agriculture were chosen as the study areas for the project. Soils and plants in area A (Edmonton area) and area B (Calgary area) were known to be deficient in selenium, while soils and plants in area C (southeast corner of Alberta) were known to have adequate levels of selenium. Blood samples were collected from 335 cows on 29 farms from the 3 study areas. These samples were collected from cows that had recently been removed from pasture in October and November 1992. Answers to a short questionnaire pertaining to various herd characteristics and management practices were also obtained for each herd. The average value of selenium for all cows sampled was 2.20 mumol/L. The average value of selenium of cows in areas A and B was 1.93 mumol/L. The average value of selenium of cows in area C was significantly (P < 0.05) higher at 2.70 mumol/L. Nine percent of the cows in the study were considered marginal or deficient in selenium (< 1.27 mumol/L selenium). Herds located in area C, herds that were provided with supplemental feed on pasture, and herds that were pregnancy checked had higher average herd selenium values than did other herds. Cow-calf producers located in areas with selenium-deficient soils should pay particular attention to selenium supplementation for their cows. Some of the negative "geographic" effects on selenium values can be overcome by more progressive management practices.     

Spontaneous neoplasms of lagomorphs.

Many of the same neoplastic processes reported in companion animal medicine have been documented in lagomorphs. With only a few reports in the literature regarding rabbits and hares, the behavior of many of these tumors cannot be predicted. Further, based on limited current knowledge, the practitioner is left to make decisions for diagnostics and therapeutics in these cases based upon current recommendations for companion animals with adjustments for lagomorph physiology. We hope that this review of lagomorph neoplasia will inform the general practitioner of the occurrence of these tumors, promote further documentation and research of these processes in rabbits, and encourage the practitioner of rabbit medicine along with rabbit owners to consult with veterinary oncologists regarding neoplastic processes in rabbits rather than just giving a guarded prognosis.     

Suspected panosteitis in a camel

CASE DESCRIPTION: A 6-month-old male Bactrian camel was examined because of a 3-week history of lameness of the left hind limb. CLINICAL FINDINGS: Lameness was initially detected in the left hind limb but resolved and was detected in the right hind limb during treatment. Lameness increased during periods of rapid growth. Radiography revealed multiple small opacities of the medullary cavity of several long bones throughout treatment. Core bone biopsies of lesions in the tibiae revealed lamellar bone with areas of loose connective tissue, osteoblasts in the medullary cavity, and periosteal new bone formation, all which were consistent with panosteitis. TREATMENT AND OUTCOME: Palliative treatment was attempted with epidural and transdermal administration of analgesics. Flunixin meglumine was administered PO, which coincided with an abrupt increase in serum creatinine concentration. Performance of multiple diagnostic bone biopsies led to remission of clinical signs of pain. CLINICAL RELEVANCE: Panosteitis should be a differential diagnosis for shifting limb lameness in young camels. Bone biopsies can be useful for diagnosis of panosteitis and possible relief of pain associated with the disease. Bactrian camels may be susceptible to the renal toxicity of flunixin meglumine, especially when dehydrated.     

B-cell lymphoma in a dog with ehrlichiosis (Ehrlichia canis) and systemic histoplasmosis (Histoplasma capsulatum)

A mixed breed dog treated for ehrlichiosis and systemic histoplasmosis developed a refractory thrombocytopenia. When an abdominal mass was detected, exploratory laparotomy and biopsies confirmed lymphoma, which on immunohistochemical stains was determined to be of B-cell origin. Conceivably, the B-cell lymphoma in this dog was associated with chronic inflammation from ehrlichiosis, histoplasmosis, or both.     

Veterinary e-CPD: a new model for providing online continuing professional development for the veterinary profession

Continuing professional development (CPD) is widely recognized as an important element in effective lifelong learning for veterinary surgeons. Traditional methods of CPD do not suit all learners, as issues such as location, time, cost, and structure sometimes prevent individuals from completing the required number of CPD study hours per year. The rapid development of the Internet, and with it the increasing scope and sophistication of e-learning, provides new opportunities to address some of these constraints on the provision of CPD. This article describes one way in which e-learning has been deployed effectively to support veterinary surgeons in practice. Since 2003, a series of six-week e-CPD courses has been offered by the Royal Veterinary College (RVC) in an online format, with no face-to-face teaching component. Participants enrolled in courses from May 2006 to January 2007 were found to come from 23 different countries. Analysis of feedback forms indicates a general satisfaction with this new way of studying, with a significant majority of participants stating that they would wish to use this approach again in future. The feedback indicates that e-learning can offer an effective alternative to traditional face-to-face courses and that its popularity is likely to grow in future as veterinarians become increasing familiar with and confident about working online.     

Evaluation of the efficacy of tulathromycin as a metaphylactic antimicrobial in feedlot calves

The purpose of this study was to determine the efficacy and cost-effectiveness of tulathromycin (DRAX) versus tilmicosin (MIC) or oxytetracycline (TET) as a metaphylactic antimicrobial in feedlot calves. Calves that received DRAX had significantly (P<.05) lower initial undifferentiated fever (UF) treatment and relapse rates; lower overall chronicity, overall mortality, and cause-specific mortality rates; higher average daily gains; and improved quality grades. However, calves that received DRAX also had poorer (P<.05) yield grades compared with calves that received MIC or TET and worse feed conversion compared with calves that received MIC. Net advantages in the DRAX group were 3.79CanDollars/animal and 16.96CanDollars/animal compared with the MIC and TET groups, respectively. Based on these results, DRAX is a more efficacious and cost-effective metaphylactic antimicrobial than MIC or TET in feedlot calves at ultra-high risk of developing UF. In addition, this study presents a comparison between two methods ("deads out" and "deads in") of calculating feedlot performance variables.     

Habitat suitability and connectivity modeling reveal priority areas for Indiana bat (Myotis sodalis) conservation in a complex habitat mosaic

Context

Conservation for the Indiana bat (Myotis sodalis), a federally endangered species in the United States of America, is typically focused on local maternity sites; however, the species is a regional migrant, interacting with the environment at multiple spatial scales. Hierarchical levels of management may be necessary, but we have limited knowledge of landscape-level ecology, distribution, and connectivity of suitable areas in complex landscapes.

Objectives

We sought to (1) identify factors influencing M. sodalis maternity colony distribution in a mosaic landscape, (2) map suitable maternity habitat, and (3) quantify connectivity importance of patches to direct conservation action.

Methods

Using 3 decades of occurrence data, we tested a priori, hypothesis-driven habitat suitability models. We mapped suitable areas and quantified connectivity importance of habitat patches with probabilistic habitat availability metrics.

Results

Factors improving landscape-scale suitability included limited agriculture, more forest cover, forest edge, proximity to medium-sized water bodies, lower elevations, and limited urban development. Areas closer to hibernacula and rivers were suitable. Binary maps showed that 30% of the study area was suitable for M. sodalis and 29% was important for connectivity. Most suitable patches were important for intra-patch connectivity and far fewer contributed to inter-patch connectivity.

Conclusions

While simple models may be effective for small, homogenous landscapes, complex models are needed to explain habitat suitability in large, mixed landscapes. Suitability modeling identified factors that made sites attractive as maternity areas. Connectivity analysis improved our understanding of important areas for bats and prioritized areas to target for restoration.

     

Pesticidal compounds from higher plants

Higher plants offer an excellent source of biologically active natural products. Over the centuries numerous plants have been exploited as sources of insecticides, but nowadays traditional botanical insecticides play only a minor role in world agriculture. Nevertheless, plant natural products still have enormous potential to inspire and influence modern agrochemical research. Few plant natural products will ever reach the market as products per se, but others will provide lead structures for programmes of synthetic chemistry and hopefully follow the success story of the synthetic pyrethroids. Structurally complex compounds, which are not amenable to synthetic chemistry programmes, may also have a role to play by validating new modes of action for pesticides. Examples are presented of compounds exhibiting insecticidal, fungicidal and herbicidal effects. Consideration is also given to the development of screening programmes to detect new compounds with interesting biological properties. Careful experimental design and thorough recording of procedures and data are crucial to success. Badly designed programmes afford only weakly active compounds or show effects which cannot be reproduced at a later date. Natural product chemistry, whether based on higher plants, micro-organisms or other sources, is a very difficult science, but there is little doubt that dedicated research will eventually be rewarded with exciting new lead structures for industrial application.