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Fox serum proteomics analysis suggests host-specific responses to angiostrongylus vasorum infection in canids
No full textDogs infected with the cardiopulmonary nematode Angiostrongylus vasorum may suffer from respiratory distress and/or bleeding disorders. Descriptions of clinical signs in foxes are rare, despite high prevalence. To evaluate the impact of infection on coagulation and immune response, serum proteins from eight experimentally infected foxes before and after inoculation (day 0, 35, 84, 154) were subjected to differential proteomic analyses based on quantitative data and compared to available data from dogs. The number of proteins with differential abundance compared to the uninfected baseline increased with chronicity of infection. Bone marrow proteoglycan, chitinase 3-like protein 1 and pulmonary surfactant-associated protein B were among the most prominently increased proteins. The abundance of several proteins involved in coagulation was decreased. Enriched pathways obtained from both increased and decreased proteins included, among others, “platelet degranulation” and “haemostasis”, and indicated both activation and suppression of coagulation. Qualitative comparison to dog data suggests some parallel serum proteomic alterations. The comparison, however, also indicates that foxes have a more adequate immunopathological response to A. vasorum infection compared to dogs, facilitating persistent infections in foxes. Our findings imply that foxes may be more tolerant to A. vasorum infection, as compared to dogs, reflecting a longer evolutionary host–parasite adaptation in foxes, which constitute a key wildlife reservoir.‘Forschungskredit’ from the University of Zurich, SwitzerlandBayer Vital GmbH, Business Unit Animal Health, German
Fluid–structure interaction and non-fourier effects in coupled electro-thermo-mechanical models for cardiac ablation
No full textIn this study, a fully coupled electro-thermo-mechanical model of radiofrequency (RF)-assisted cardiac ablation has been developed, incorporating fluid–structure interaction, thermal relaxation time effects and porous media approach. A non-Fourier based bio-heat transfer model has been used for predicting the temperature distribution and ablation zone during the cardiac ablation. The blood has been modeled as a Newtonian fluid and the velocity fields are obtained utilizing the Navier–Stokes equations. The thermal stresses induced due to the heating of the cardiac tissue have also been accounted. Parametric studies have been conducted to investigate the effect of cardiac tissue porosity, thermal relaxation time effects, electrode insertion depths and orientations on the treatment outcomes of the cardiac ablation. The results are presented in terms of predicted temperature distributions and ablation volumes for different cases of interest utilizing a finite element based COMSOL Multiphysics software. It has been found that electrode insertion depth and orientation has a significant effect on the treatment outcomes of cardiac ablation. Further, porosity of cardiac tissue also plays an important role in the prediction of temperature distribution and ablation volume during RF-assisted cardiac ablation. Moreover, thermal relaxation times only affect the treatment outcomes for shorter treatment times of less than 30 s.Natural Sciences and Engineering Research Council (NSERC) of CanadaCanada Research Chairs (CRC) Progra
Species-specific PCR assay for the detection of Babesia odocoilei
No full textWe developed a PCR assay for the detection of Babesia odocoilei based on the 18S rRNA gene. Multiple specimens of B. odocoilei were examined, and the assay consistently produced a small specific PCR product of 306 bp. The PCR assay was also challenged with DNA from 13 other Babesia species and 2 Theileria species, originating from 10 different host species; however, nonspecific DNA amplification and multiple banding patterns were observed, and the amplicon banding patterns varied between different isolates of the same species. Sensitivity was determined to be 6.4 pg of DNA, and an estimated 0.0001% parasitism. This assay can be utilized for species-specific differential detection of B. odocoilei
Never‐ending repetitiveness, sadness, loss, and “juggling with a blindfold on”: Lived experiences of Canadian college and university faculty members during the COVID‐19 pandemic
No full textWe report on the lived experiences of faculty members during the early months of the COVID-19 pandemic, exploring the broader experiences of faculty members as individuals living multifaceted lives whose homes became their offices, their students scattered geographically and their home lives upended. Using a phenomenological approach for data collection and analysis, we conducted 20 in-depth interviews with faculty holding varied academic appointments at universities across Canada. Experiences during the early months of the pandemic were described as being overwhelming and exhausting, and participants described as being stuck in a cycle of never-ending repetitiveness, sadness and loss, or managing life, teaching and other professional responsibilities with little sense of direction. In keeping with phenomenological methods, this research paints a visceral picture of faculty experiences, seeking to contextualize teaching and learning during this time. Its unique contribution lies in portraying emergency remote teaching as an overlapping and tumultuous world of personal, professional and day-to-day responsibilities
Spatial and temporal patterns in the sex ratio of American lobsters (Homarus americanus) in southwestern Nova Scotia, Canada
No full textAn approximate 1:1 sex ratio of American lobsters can be skewed due to environmental factors or
fsheries management. Substantial skewness can impact mating behaviour and lower reproduction
which could have far-reaching ecological and economic consequences. The aim was to investigate
the sex ratio patterns of lobsters in two lobster fshing areas (LFAs) in southwestern Nova Scotia,
Canada and identify factors associated with skewed sex ratios. This study analyzed biological data
from more than 270,000 lobsters sampled over ten years (2010–2019) by the Fishermen and Scientists
Research Society. A mixed efect logistic regression model evaluated the efect of spatial, temporal
and environmental factors as well as size on the sex ratio of lobsters. There were signifcant temporal
patterns in sex ratios that difered by LFA. After the efects of sampling month, year and LFA were
accounted for, lower bottom temperature and deeper water depth were associated with a higher
prevalence of females, especially in larger lobsters. We present the frst long term analyses of sex ratio
patterns in H. americanus in Atlantic Canada’s most commercially important region for this species and
provide evidence that these patterns are infuenced by environmental factors and fsheries. In view of
future climate change scenarios, monitoring the population dynamics of this iconic fshery species is
crucial to ensure sustainable fsheries and healthy lobster stocks
Environmental refuges increase performance of juvenile mussels Mytilus chilensis: Implications for mussel seedling and farming strategies
No full textEstuarine ecosystems are characterized by a wide physical-chemical variation that in the context of global change scenarios may be exacerbated in the future. The fitness of resident organisms is expected to be influenced by such variation and, hence, its study is a priority. Some of that variation relates to water vertical stratification, which may create “environmental refuges” or distinct layers of water with conditions favoring the fitness of some individuals and species. This study explored the performance of juvenile mussels (M. chilensis) settled in two distinctive water depths (1 m and 4 m) of the Reloncaví fjord (southern Chile) by conducting a reciprocal transplants experiment. Salinity, saturation state and the contents of CO3 in seawater were among the factors that best explained the differences between the two layers. In such environmental conditions, the mussel traits that responded to such variation were growth and calcification rates, with significantly higher values at 4 m deep, whereas the opposite, increased metabolic stress, was higher in mussels raised and transplanted to the surface waters (1 m). Such differences support the notion of an environmental refuge, where species like mussels can find better growth conditions and achieve higher performance levels. These results are relevant considering the importance of M. chilensis as a shellfish resource for aquaculture and a habitat forming species. In addition, these results shed light on the variable responses exhibited by estuarine organisms to small-scale changes in the characteristics of the water column, which in turn will help to better understand the responses of the organisms to the projected scenarios of climate global change
Creating enriched training sets of eligible studies for large systematic reviews: the utility of PubMed's Best Match algorithm
No full textIntroduction
Solutions like crowd screening and machine learning can assist systematic reviewers with heavy screening burdens but require training sets containing a mix of eligible and ineligible studies. This study explores using PubMed's Best Match algorithm to create small training sets containing at least five relevant studies.
Methods
Six systematic reviews were examined retrospectively. MEDLINE searches were converted and run in PubMed. The ranking of included studies was studied under both Best Match and Most Recent sort conditions.
Results
Retrieval sizes for the systematic reviews ranged from 151 to 5,406 records and the numbers of relevant records ranged from 8 to 763. The median ranking of relevant records was higher in Best Match for all six reviews, when compared with Most Recent sort. Best Match placed a total of thirty relevant records in the first fifty, at least one for each systematic review. Most Recent sorting placed only ten relevant records in the first fifty. Best Match sorting outperformed Most Recent in all cases and placed five or more relevant records in the first fifty in three of six cases.
Discussion
Using a predetermined set size such as fifty may not provide enough true positives for an effective systematic review training set. However, screening PubMed records ranked by Best Match and continuing until the desired number of true positives are identified is efficient and effective.
Conclusions
The Best Match sort in PubMed improves the ranking and increases the proportion of relevant records in the first fifty records relative to sorting by recency
A focus group study of Ontario dairy producer perspectives on neonatal care of male and female calves
No full textProviding optimal calf care remains a challenge on
many dairy farms and has important implications for
the future health, welfare, and productivity of male
and female calves. Recent research suggests that male
dairy calves receive a lower quality of care early in life
than female calves, but further investigation is required
to determine the factors that influence this disparity.
The objectives of this study were to understand dairy
producer perspectives on neonatal calf care practices
and explore differences between male and female calf
care. Overall, 23 dairy producers in Ontario, Canada,
participated in 4 focus groups about calf care practices
that were recorded and evaluated qualitatively using
thematic analysis. Major barriers for good calf care
included lack of knowledge about the best management
practices for calf care and the prioritization of farm
resources toward the milking herd. Some producers
also noted that farm infrastructure (particularly during
challenging weather) and employee training were important limitations. The economic cost of providing good
neonatal calf care was important primarily for male
calves and acted as a motivation or a barrier depending
on the producer’s beliefs about calf care and how they
chose to market their calves. The primary source of
knowledge producers used to develop calf care practices
was their own experience, although many also relied
on dairy-industry advisors, most often veterinarians.
Producers were motivated by social norms, along with
intrinsic pride and obligation to provide good calf care,
and these motives were influenced by their emotional
state. Producers expressed beliefs about which aspects
of calf care are most important—notably colostrum
management—and appreciated simple and economical
solutions to calf-rearing challenges. Calf care practices
were varied, and we identified a diversity of knowledge,
motivations, and barriers to adopting best management
practices, which sometimes differed between male and
female calves. Some producers said that they did not
know what happened to their male calves after they
left the farm and tended to prioritize the care of female
over male calves in subtle ways, such as less timely provision of colostrum. The infrastructure investment and
other costs associated with caring for male calves often
limited their care, but producers were still motivated to
provide adequate care for male calves. These findings
represent potential targets for additional research and
intervention strategies to improve calf care practices on
dairy farms.National Institute of Food and Agricultur
Application of deep learning to detect Lamb’s quarters (Chenopodium album L.) in potato fields of Atlantic Canada
No full textExcessive use of herbicides for weed control increases the cost of crop production and can lead to environmental degradation. An intelligent spraying system can apply agrochemicals on an as-needed basis by detecting and selectively targeting the weeds. The objective of this research was to investigate the feasibility of using deep convolutional neural networks (DCNNs) for detecting lamb’s quarters (Chenopodium album) in potato fields. Five potato fields were selected in Prince Edward Island (PEI) and New Brunswick (NB), Canada to collect images of spatially and temporally varied potato plants and lamb’s quarters. The image database included pictures, taken under varying growth stages of potato, outdoor light (clear, cloudy, and partly cloudy), and shadowy conditions. The images were trained for DCNN models, namely GoogLeNet, VGG-16, and EfficientNet to classify lamb’s quarters and potato plants. Performance of two frameworks, namely TensorFlow and PyTorch, were compared in training, testing, and during inferring the DCNNs. Results showed excellent performance of DCNNs in lamb’s quarters and potato plant classification (accuracy > 90%). However, the EfficientNet with PyTorch framework showed a maximum accuracy of (0.92–0.97) for every growth stage of the plants. Inference times of DCNNs were recorded using three graphics processing units (GPUs), namely Nvidia GeForce 930MX, Nvidia GeForce GTX1080 Ti, and Nvidia GeForce GTX1050. All the DCNNs performed better with PyTorch than TensorFlow frameworks. It was concluded that the trained models can be used in automation of the spraying systems for the site-specific application of agrochemicals for weed control in potato fields. Such precision agriculture technologies will ensure economically viable and environmentally safe potato cultivation
Investigation of spatio‐temporal clusters of positive leptospirosis polymerase chain reaction test results in dogs in the United States, 2009 to 2016
No full textBackground
Leptospirosis is a zoonotic disease of concern and an investigation of recent spatio‐temporal trends of leptospirosis in dogs in the United States is needed. Leptospira PCR testing has become increasingly used in veterinary clinical medicine and these data might provide information on recent trends of disease occurrence.
Objectives
To identify and describe clusters of PCR‐positive Leptospira test results in dogs in the United States.
Animals
Leptospira real‐time PCR test results from dogs (n = 40 118) in the United States from IDEXX Laboratories, Inc., between 2009 and 2016 were included in the analysis.
Methods
In this retrospective study, spatio‐temporal clusters for a real‐time PCR‐positive test were identified using the space‐time permutation scan statistic and the centroid of the zip code reported for each test. A maximum spatial window of 20% of the population at risk, and a maximum temporal window of 6 months were used.
Results
Seven statistically significant space‐time clusters of Leptospira real‐time PCR‐positive test results were identified across the United States: 1 each located within the states of Arizona (2016), California (2014‐2015), Florida (2010), South Carolina (2015), and 1 each located within the south‐central region (2015), midwest region (2014), and northeast region (2011). Clusters ranged from 3 to 108 dogs and were identified during all years under study, except 2009, 2012, and 2013.
Conclusions and Clinical Importance
The spatial and temporal components of leptospirosis in dogs in this study are similar to those in previous work. However, clusters were identified in new areas, demonstrating the complex epidemiology of this disease.American Kennel Club Canine Health Foundatio