MOTOR AND SENSORY NERVE CONDUCTION STUDY IN THE FERRET

Ferrets are considered a popular small mammal pet, and like other companion animals they are reported to suffer from diseases affecting the neuromuscular system. There currently is a lack of comprehensive electrodiagnostic study regarding the appendicular nerves of ferrets. In this research investigation, 25 domestic ferrets were used for electromyography and motor nerve conduction studies of the tibial, fibular, ulnar, and radial nerves, including H reflexes of the tibial and ulnar nerves, as well as sensory conduction of the fibular nerve. Mean and standard deviations for motor and sensory nerve studies were established. The hypothesis that weight would be correlated with all distal and proximal compound muscle action potential latencies was tested and confirmed for the tibial, fibular, and radial nerves but not the ulnar nerve.     

Connectivity of mule deer (Odocoileus hemionus) populations in a highly fragmented urban landscape

Context

Urbanization is a substantial force shaping the genetic and demographic structure of natural populations. Urban development and major highways can limit animal movements, and thus gene flow, even in highly mobile species. Characterizing varying species responses to human activity and fragmentation is important for maintaining genetic continuity in wild animals and for preserving biodiversity. As one of the only common and wide-ranging large wild herbivores in much of urban North America, deer play an important ecological role in urban ecosystems, yet the genetic impacts of development on deer are not well known.

Objectives

We assessed genetic connectivity for mule deer to understand their genetic response to habitat fragmentation, due to development and highway barriers, in an increasingly urbanized landscape.

Methods

Using non-invasive sampling across a broad region of southern California, we investigated genetic structure among several natural areas that were separated by major highways and applied least-cost path modelling to determine if landscape context and highway attributes influence genetic distance for mule deer.

Results

We observed significant yet variable differentiation between subregions. We show that genetic structure corresponds with highway boundaries in certain habitat patches, and that particular landscape configurations more greatly limit gene flow between patches.

Conclusions

As a large and highly mobile species generally considered to be well adapted to human activity, mule deer nonetheless showed genetic impacts of intensive urbanization. Because of this potential vulnerability, mule deer and other ungulates may require further consideration for effective habitat management and maintenance of landscape connectivity in human-dominated landscapes.

     

Application of multiplex quantitative polymerase chain reaction methods to detect common bacterial fish pathogens in Nile tilapia,Oreochromis niloticus,hatcheries in Costa Rica

Edwardsiella spp., Streptococcus spp., and Francisella noatunensis subsp. orientalis are some of the most important fish pathogens affecting global tilapia, Oreochromis spp., aquaculture. In Costa Rica, the aquaculture industry is dominated by freshwater‐cultured Nile tilapia, Oreochromis niloticus, which are raised in all seven national provinces. At present, little is known regarding the diversity of pathogens present in these facilities, and definitive identification of agents associated with disease outbreaks are rare. To evaluate the prevalence of common bacterial pathogens in these systems, this study used multiplex quantitative polymerase chain reaction (qPCR) assays targeting Edwardsiella, Streptococcus, and Francisella species as a diagnostic and surveillance tool. In 2017, seven different tilapia hatcheries were visited, and 350 fingerlings were subjected to necropsy and molecular diagnostic evaluation. Fish exhibiting gross signs of disease were subjected to histological and microbiological analysis. For the first time, Edwardsiella anguillarum was recovered and molecularly confirmed from diseased tilapia in Costa Rica. In addition, F. noatunensis subsp. orientalis was identified in a region of Costa Rica where it had not been previously reported.     

Chromobacterium violaceum infection in two dogs

Chromobacterium violaceum is a saprophyte of soil and water in tropical and subtropical environments that is associated with rare but highly fatal infections in animals and humans. Systemic infection was diagnosed in two critically ill dogs from Florida. Fever was absent in both dogs. Both dogs were treated surgically and provided with intensive care, but only one survived. The identification of characteristic, violet-pigmented bacterial colonies on routine microbial cultures should alert microbiologists and clinicians to the likelihood of this dangerous pathogen. Because of the rapidly progressive nature of this infection, empirical antibiotic administration with fluoroquinolones should be employed pending susceptibility testing.     

Evaluation of detemir in diabetic cats managed with a protocol for intensive blood glucose control

The aim of this study was to report outcomes using detemir and a protocol aimed at intensive blood glucose control with home monitoring in diabetic cats, and to compare the results with a previous study using the same protocol with glargine. Eighteen cats diagnosed with diabetes and previously treated with other insulins were included in the study. Data was provided by owners who joined the online German Diabetes-Katzen Forum. The overall remission rate was 67%. For cats that began the protocol before or after 6 months of diagnosis, remission rates were 81% and 42%, respectively (P = 0.14). No significant differences were identified between the outcomes for the glargine and detemir studies, with the exception of three possibly interrelated factors: a slightly older median age of the detemir cohort at diabetes diagnosis, a higher rate of chronic renal disease in the detemir cohort and lower maximal dose for insulin detemir.     

Cost estimation of heifer mastitis in early lactation by stochastic modelling

Heifer mastitis, reflected by an elevated somatic cell count (SCC) in early lactation (SCCel), results in a decreased milk production, a higher risk for subclinical and clinical mastitis during lactation, and an elevated culling hazard. The aims of this study were to calculate the costs of heifer mastitis defined as an elevated SCC in early lactation, and to show the variation of these costs in the Dutch/Belgian dairy sector. A stochastic model, in which the variation and uncertainty of heifer mastitis are taken into the account, was developed with input data from literature and expertise. Costs were estimated, using default values. The mean costs for an elevated SCCel that cured were on average euro 13/heifer present on a farm (range: euro 0-118), for an elevated SCC at calving proceeding in subclinical mastitis on average euro 5/heifer present on a farm (range: euro 0-euro 82), and for a clinical heifer mastitis case associated with an elevated SCC after calving on average euro 270. On average this results in euro 13/heifer present on a farm (range: euro 0-137). Combined, these three cost aspects result in a total cost of on average euro 31/heifer present on a farm (range: euro 0-220). The large variation in the costs is very important regarding farm management and farm support. The difference in costs reflects also the difference in room for investment. When the costs that can be prevented are estimated at farm level, these data can be of help in setting goals in herd health advice and farm management.     

Immunophenotyping of chicken peripheral blood lymphocyte subpopulations: individual variability and repeatability

T-cell lymphocyte populations can be delineated into subsets based on expression of cell surface proteins that can be measured in peripheral blood by monoclonal antibodies and flow cytometry percentages of the lymphocyte subpopulations. In order to accurately assess immunocompetence in birds, natural variability in both avian immune function and the methodology must be understood. Our objectives were to (1) further develop flow cytometry for estimating subpopulations of lymphocytes in peripheral blood from poultry, (2) estimate repeatability and variability in the methodology with respect to poultry in a free-range and environmentally diverse situation, and (3) estimate the best antibody and cell marker combination for estimating lymphocyte subpopulations. This work demonstrated the repeatability of using flow cytometry for measurements of peripheral blood in chickens using anti-chicken antibodies for lymphocyte subpopulations. Immunofluorescence staining of cells isolated from peripheral blood revealed that the CD3(+) antibodies reacted with an average of approximately 12-24% of the lymphoid cells in the blood, depending on the fluorescence type. The CD4(+) and CD8(+) molecules were expressed in a range of 4-31% and 1-10% of the lymphoid cells in the blood, respectively. Both fluorescence label and antibody company contribute to the variability of results and should be considered in future flow cytometry studies in poultry.