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Atlantic salmon aquaculture companies in British Columbia (BC) must report fish health events to Fisheries and Oceans Canada (DFO) as part of their licensing conditions. Our study aimed to summarize these fish health events reported by Atlantic salmon sites in BC to identify spatial and spatio-temporal clusters. We conducted descriptive, retrospective global, and local cluster analyses using Moran's I and scan statistics. Between 2016 and 2022, 265 fish health events were reported. The annual incidence ranged from 5.60 (95% CI: 3.90-7.80) to 6.86 (95% CI: 4.70-9.60) health events per 100 active site-months. The most common events were yellow mouth (60.75%; 161/265) and salmonid rickettsial septicaemia (SRS) (15.47%; 41/265). The Moran's I index was positive and significant for yellow mouth, SRS, and overall fish health events at different distance bands. Most of the spatial and spatio-temporal clusters were identified in the west-central and southwestern parts of Vancouver Island. Our study hypothesizes that management practices, environmental conditions, and water quality parameters may have influenced the increased reporting of fish health events in these regions. Overall, the study highlights the potential of publicly available data for practical risk mapping in understanding the patterns of farmed Atlantic salmon diseases in BC., (© 2024 The Author(s). Journal of Fish Diseases published by John Wiley & Sons Ltd.)

Microbiota analyses are key to understanding the bacterial communities within dairy cattle, but the impact of different storage conditions on these analyses remains unclear. This study sought to examine the effects of freezing at -80°C immediately after collection, refrigeration at 4°C for three days and seven days and absolute ethanol preservation on the microbiota diversity of pooled fecal samples from dairy cattle. Examining 16S rRNA gene sequences, alpha (Shannon, Pielou evenness, observed features and Faith PD indices) and beta (Bray-Curtis, βw and Weighted UniFrac) diversity were assessed. The effects of storage conditions on these metrics were evaluated using linear mixed models and PERMANOVA, incorporating the farm as a random effect. Our findings reveal that 7d and E significantly altered the Shannon index, suggesting a change in community composition. Changes in Pielou evenness for 3d and 7d storage when compared to 0d were found, indicating a shift in species evenness. Ethanol preservation impacted both observed features and Faith PD indices. Storage conditions significantly influenced Bray-Curtis, βw, and Weighted UniFrac metrics, indicating changes in community structure. PERMANOVA analysis showed that these storage conditions significantly contributed to microbiota differences compared to immediate freezing. In conclusion, our results demonstrate that while refrigeration for three days had minimal impact, seven days of refrigeration and ethanol preservation significantly altered microbiota analyses. These findings highlight the importance of sample storage considerations in microbiota research., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Jaramillo-Jaramillo et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

The objective of this randomized controlled trial was to assess the relative merits of offering unweaned calves 3 different types of diets to meet energy and water deficits that can occur during journeys. Six young unweaned male Holstein calves were randomly selected from within 2 body weight ranges (median 48 and 42 kg) from each of 29 loads (total n = 174 calves) transported from an auction market or a collection center to a calf sorting center before transport to a veal unit. The calves were then randomly allocated to one of 3 dietary treatments (n = 58 calves/dietary treatment). They were offered either a milk replacer diet (M), a glucose-electrolyte diet (G) or a whey-based diet with added electrolytes (W). The ability of these diets to provide sufficient nutrient energy to restore vigor, avoid hypoglycaemia and clinical signs of dehydration without increasing the risk of diarrhea was assessed. A clinical assessment of dehydration, health and vigor was made, and the calves were blood sampled before feeding, then 2 h and 4 h after feeding. The plasma glucose concentration was increased 2 h and 4 h after feeding the M and W diets. The increases in plasma glucose concentration were greater 2 and 4 h after (a) feeding the M than after the W diet and (b) feeding the M and W diets than after the G diet. Back-transformed means and 95% Confidence Intervals (CI) for the ratio of the plasma glucose concentration at 4 h compared with 0 h for the milk replacer, glucose-electrolytes and whey-based diets were 1.2 mM CI 1.21, 1.35; 0.95 mM CI 0.92, 0.97; and 1.09 mM CI 1.06, 1.14, respectively. There was no effect of diet on the change in serum total protein concentration between before feeding and 2 and 4 h after feeding. The serum osmolality was lower 2 h after feeding the G diet. The fall in serum osmolality was greater 2 h after feeding the G diet than after feeding the M and W diets. The changes in the serum osmolality between before feeding and 2 h after feeding for the milk replacer, glucose-electrolytes and whey-based diets were -0.68 mosmol CI -3.27, 1.91; -5.23 mosmol CI -7.82, and -2.64; -0.13 mosmol CI -2.77, 2.51, respectively. The diet offered at the sorting center had no effect on subsequent growth on the veal rearing farm between arrival and slaughter (milk replacer 1.22 kg/d, CI 1.17, 1.28; glucose-electrolyte diet 1.23 kg/d. CI 1.18, 1.28; whey-based diet 1.28 kg/d CI 1.23, 1.33). The M diet provided the calves with nutrients and water to replace energy and water deficits that had accumulated before arrival at the sorting center, and these dietary benefits were still apparent 4 h after feeding. The benefits of the W diet were similar to those of the M diet, but the M diet was better able to assist the calves in maintaining their plasma glucose concentration 4 h after feeding than the W diet. The G diet had some short-term benefits in providing energy and assistance to the calves to recover from dehydration, as indicated by a decrease in serum osmolality. However, the G diet was clearly inferior to the M and W diets in providing sufficient energy to assist the calves in recovering from the effects of transport and fasting. During the 4-h after feeding, no adverse effects of offering the calves the M or W diets were observed. The benefits of the W diet in replacing energy and water deficits were similar to those of the M diet, but the M diet was better able to assist the calves in maintaining their blood glucose concentration 4 h after feeding than the W diet., (The Authors. Published by Elsevier Inc. on behalf of the American Dairy Science Association®. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).)

Objective: The primary objective was to determine the youngest age group where bovine leukemia virus (BLV)-infected dairy animals were identified. The secondary objective was to investigate associations between age-specific management practices and BLV infection status of different age groups of dairy calves and heifers., Procedure: For enrolled herds, BLV status was determined using blood samples from pre-weaned calves, weaned calves, and breeding-age heifers; and bulk tank milk from the adult herd. A questionnaire investigating age-specific management factors was administered for each herd. Ordinal logistic regression was performed to identify management factors associated with the youngest age range in which BLV was identified., Results: Fifty-three dairy herds from the 4 provinces in Atlantic Canada were enrolled. Bovine leukemia virus was most commonly earliest identified in pre-weaned heifers (18 herds, 32.1%) and the adult herd (18 herds, 32.1%). Ordinal logistic regression revealed that BLV was first identified in older age groups more often than in younger age groups when herds regrouped weaned heifers at least once, when fly control was used for breeding-age heifers, when herds practiced foot trimming on breeding-age heifers, and when bred heifers were brought in., Conclusion: Producers can use results to identify the youngest age group(s) in which BLV is identified and to tailor management strategies to prevent new infections., (Copyright and/or publishing rights held by the Canadian Veterinary Medical Association.)

Salmonellosis is one of the leading causes of gastrointestinal infections in humans. In Canada, it is estimated that approximately 87,500 cases of salmonellosis occur every year in humans, resulting in 17 deaths. In the United States, it is estimated that 26,500 hospitalizations and 420 deaths occur every year. In dairy cattle, infections caused by nontyphoidal Salmonella enterica can cause mild to severe disease, including enteritis, pneumonia, and septicemia. Our study objectives were to determine the proportion of fecal samples positive for Salmonella in dairy cattle in Canada and determine the resistance pattern of these isolates. We used data collected through the Canadian Dairy Network for Antimicrobial Stewardship and Resistance (CaDNetASR). Pooled fecal samples from preweaning calves, postweaning heifers, lactating cows, and manure storage were cultured for Salmonella, and the isolates were identified using matrix-assisted laser desorption/ionization-time of flight mass spectrometry. Antimicrobial susceptibilities were determined using the minimum inhibitory concentration test, and resistance interpretation was made according to the Clinical and Laboratory Standards Institute. A 2-level, multivariable logistic regression model was built to determine the probability of recovering Salmonella from a sample, accounting for province, year, and sample source. The proportion of farms with at least one positive sample were 12% (17/140), 19% (28/144), and 17% (24/144) for the sampling years 2019, 2020, and 2021, respectively. Out of the 113 Salmonella isolates, 23 different serovars were identified. The occurrence of Salmonella appeared to be clustered by farms and provinces. The most common serovars identified were Infantis (14%) and Typhimurium (14%). Overall, 21% (24/113) of the Salmonella isolates were resistant to at least one antimicrobial. Resistance to tetracycline was commonly observed (17%); however, very limited resistance to category I antimicrobials (categorization according to Health Canada that includes third-generation cephalosporins, fluoroquinolones, polymyxins, and carbapenems) was observed, with one isolate resistant to amoxicillin and clavulanic acid. The proportion of Salmonella isolates resistant to 2 and 3 antimicrobial classes was 3.5% and 8.8%, respectively. Our study provided valuable information on the proportion of fecal samples positive for Salmonella, the serovars identified, and the associated resistance patterns across CaDNetASR herds, at regional and national levels., (The Authors. Published by Elsevier Inc. on behalf of the American Dairy Science Association®. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).)

Host-microbe dynamics are of increasing interest in marine research due to their role in host health and productivity. Changes in the shell microbiome of American lobsters have been associated with epizootic shell disease, a syndrome that is spreading northwards across the eastern U.S. and Canadian Atlantic coast. This study analyzed differences in alpha and beta diversity, as well as differentially abundant taxa, in the shell-associated bacterial community of apparently healthy lobsters from four lobster fishing areas (LFAs) in Atlantic Canada. Over 180 lobsters from New Brunswick, Nova Scotia and Prince Edward Island (PEI) were sampled during seven sampling events over four sampling months. The bacterial community was identified using novel PacBio long-read sequencing, while alpha and beta diversity parameters were analyzed using linear regression models and weighted UniFrac distances. The bacterial richness, diversity and evenness differed by sampling location, sampling month, and molt stage, but not by lobster sex or size, nor sampling depth. Similarly, based on LFA, sampling month, year and lobster molt stage, the shell microbiome differed in microbial community composition with up to 34 out of 162 taxa differing significantly in abundance between sampling groups. This large-scale microbial survey suggests that the shell microbial diversity of apparently healthy lobsters is influenced by spatial and temporal factors such as geographic location, as well as the length of time the carapace is exposed to the surrounding seawater., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2024 Koepper, Clark, McClure, Revie, Stryhn and Thakur.)

Calf management and health are essential for setting up the foundation of a productive cow. The objectives of this study were to estimate the impact of preweaning practices on milk production parameters while accounting for an animal's genetic potential in New Brunswick, Canada. A retrospective cohort study was performed on 220 heifer calves from eight herds born in 2014-2015. Preweaning practices and health data were recorded by producers and reviewed by the herd veterinarian for each calf. The herd veterinarian also visited the farms to collect serum samples from calves and frozen colostrum samples. The production outcomes assessed were milk, protein and fat yields, standardized to 305 d for the first lactation (L1) and a combined group of lactations two and three (L2 + 3). The genomic potential was determined as genomic parent averages (GPA) for the associated production parameters. Analysis was performed with multivariable linear (L1) and linear mixed (L2 + 3) regression models. In L1, for every 1.0 kg increase in weaning weight, milk, protein, and fat yield increased by 25.5, 0.82, and 1.01 kg, respectively (P < 0.006). Colostrum feeding time (CFT) positively impacted L1 milk and protein production, with feeding between 1-2 h of life producing the greatest estimates of 626 kg of milk and 18.2 kg of protein yield (P < 0.007), compared to earlier or later CFT. Fat yield production was decreased by 80.5 kg (P < 0.006) in L1 when evaluating animals that developed a preweaning disease and were not treated with antibiotics compared to healthy untreated animals. Impacts on L2 + 3 were similar across all production outcomes, with a positive interaction effect of CFT and weaning weight. Compared to CFT < 1 h, the later CFT groups of 1-2 h and > 2 h produced greater yield outcomes of 68.2 to 72.6 kg for milk (P < 0.006), 2.06 to 2.15 kg for protein (P < 0.005), and 1.8 to 1.9 kg for fat (P < 0.045) for every 1 kg increase of weaning weight, respectively. The fit of all models was significantly improved with the inclusion of GPA. These results indicate that colostrum management and preweaning health measures impacted production parameters as adults. The inclusion of GPA significantly improved the accuracy of the models, indicating that this can be an important parameter to include in future studies., (© The Author(s) 2024. Published by Oxford University Press on behalf of the American Society of Animal Science.)

Objective: This study determined the in vitro efficacy of 6 common anthelmintics (eprinomectin, ivermectin, milbemycin oxime, moxidectin, selamectin, and fenbendazole) on motility (viability) of infectious third-stage larvae (L3) of Crenosoma vulpis, Angiostrongylus vasorum, and Aelurostrongylus abstrusus, which are important causes of canine and feline cardiopulmonary disease., Samples: First-stage larvae (L1) from C vulpis, An vasorum, and Ae abstrusus., Procedures: Naïve Limax maximus slugs were fed 1,000 to 2,000 L1 and held at 16 °C for at least 4 weeks to produce live L3. Approximately 50 to 100 L3/well were subsequently incubated in culture media alone or media containing 6 separate test anthelmintics at 4 concentrations, to bracket expected in vivo drug plasma levels in anthelmintic-treated dogs and cats. Drug effects on L3 motility (viability) were analyzed by multilevel logistic models, generating dose-response relationships. Experiments were completed 1-9/2019., Results: Drug concentration estimates corresponding to a 50% larval mortality rate identified that C vulpis was the most sensitive species to the anthelmintics tested. Ae abstrusus was most susceptible to moxidectin and selamectin, while An vasorum was insusceptible to all anthelmintics tested, except for selamectin at high drug concentrations., Clinical Relevance: The in vitro anthelmintic response to antiparasitic agents may guide and improve disease therapy and prevention. Considering the observed lack of efficacy against L3, monthly anthelmintic treatment for protection against An vasorum infection in dogs would primarily rely on the anthelmintic's adulticidal activity. Maximal preventive control for An vasorum would, therefore, require at least 1 treatment administered a minimum of 1 week after the end of the transmission season.

Size distribution and size frequency information of American lobsters (Homarus americanus) are often used to help estimate the age distributions, and reproductive output for the species and to guide the determination of appropriate minimum legal sizes for the fishery. This study used truncated linear regression models to estimate the effects of sampling year, sampling month, lobster sex and water depth on the lobster size. A dataset of almost 130,000 trap-caught lobsters from the two most important lobster fishing areas of Atlantic Canada collected over a 12-year period (2004-2015) was analyzed. It was shown that truncated models can help to account for biases due to the trap sampling method from vessels and from wharf samplings. There were significant annual and seasonal changes in size distribution, and data collected outside the fishing season showed a significant increase in carapace length in 2014 and 2015, potentially reflecting a northward shift of the range of lobster populations due to more favourable settlement and recruitment habitats. Size also increased in late summer, likely due to moult. Our results demonstrated that landed lobsters, especially females, were smaller than the predicted size-at-maturity in the region (96.5 mm carapace length), which could have long-term repercussions for the stock's reproductive potential., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Koepper et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: Data extraction (DE) is a challenging step in systematic reviews (SRs). Complex SRs can involve multiple interventions and/or outcomes and encompass multiple research questions. Attempts have been made to clarify DE aspects focusing on the subsequent meta-analysis; there are, however, no guidelines for DE in complex SRs. Comparing datasets extracted independently by pairs of reviewers to detect discrepancies is also cumbersome, especially when the number of extracted variables and/or studies is colossal. This work aims to provide a set of practical steps to help SR teams design and build DE tools and compare extracted data for complex SRs., Methods: We provided a 10-step guideline, from determining data items and structure to data comparison, to help identify discrepancies and solve data disagreements between reviewers. The steps were organised into three phases: planning and building the database and data manipulation. Each step was described and illustrated with examples, and relevant references were provided for further guidance. A demonstration example was presented to illustrate the application of Epi Info and R in the database building and data manipulation phases. The proposed guideline was also summarised and compared with previous DE guidelines., Results: The steps of this guideline are described generally without focusing on a particular software application or meta-analysis technique. We emphasised determining the organisational data structure and highlighted its role in the subsequent steps of database building. In addition to the minimal programming skills needed, creating relational databases and data validation features of Epi info can be utilised to build DE tools for complex SRs. However, two R libraries are needed to facilitate data comparison and solve discrepancies., Conclusions: We hope adopting this guideline can help review teams construct DE tools that suit their complex review projects. Although Epi Info depends on proprietary software for data storage, it can still be a potential alternative to other commercial DE software for completing complex reviews., (© 2023. The Author(s).)

The shell microbial community of lobsters-a key factor in the development of epizootic shell disease (ESD)-is still insufficiently researched in Atlantic Canada and many knowledge gaps remain. This study aimed to establish a baseline description and analysis of the shell microbiome of apparently healthy lobsters from four locations in the region. More than 180 lobster shell swab samples were collected from New Brunswick, Nova Scotia and Prince Edward Island (PEI). PacBio long-read 16S rDNA sequencing and bioinformatic analyses in QIIME2 identified the shell-associated bacteria. The shell microbiome of healthy lobsters consisted mainly of the bacterial classes Gammaproteobacteria , Saprospiria , Verrucomicrobiae , Alphaproteobacteria , Flavobacteriia , Acidimicrobiia and Planctomycetia . The microbial composition differed regionally and seasonally, with some classes showing decreased or increased relative abundances in the PEI samples as well as in the winter and spring samples in Nova Scotia. The core shell microbiome included potentially pathogenic as well as beneficial bacterial taxa, of which some were present only in certain regions. Bacterial taxa that have previously been associated with ESD were present on healthy lobsters in Atlantic Canada, but their frequency differed by location, sampling time, and moult stage. This study indicated that geographical and seasonal factors influenced the shell microbiome of apparently healthy lobsters more than host factors such as sex, size, and moult stage. Our results provide valuable reference microbial data from lobsters in a disease-free state., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Koepper, Clark, McClure, Revie, Stryhn and Thakur.)

Antimicrobial resistance (AMR) in animals, including dairy cattle, is a significant concern for animal and public health worldwide. In this study, we used data collected through the Canadian Dairy Network for Antimicrobial Stewardship and Resistance (CaDNetASR) to: (1) describe the proportions of AMR in fecal E. coli, and (2) investigate the relationship between antimicrobial use (AMU) (intramammary and systemic routes, while accounting for confounding by other variables) and AMR/multidrug resistance (MDR - resistance to ≥ 3 antimicrobial classes) in fecal E. coli from Canadian dairy farms. We hypothesized that an increase of the AMU was associated with an increase in AMR in E. coli isolates. A total of 140 dairy farms across five provinces in Canada were included in the study. Fecal samples from pre-weaned calves, post-weaned heifers, lactating cows, and farm manure storage were cultured, and E. coli isolates were identified using MALDI-TOF MS. The minimum inhibitory concentrations (MIC) to 14 antimicrobials were evaluated using a microbroth dilution methodology. AMU was quantified in Defined Course Dose (DCD - the dose for a standardized complete treatment course on a standard size animal) and converted to a rate indicator - DCD/100 animal-years. Of 1134 fecal samples collected, the proportion of samples positive for E. coli in 2019 and 2020 was 97.1% (544/560) and 94.4% (542/574), respectively. Overall, 24.5% (266/1086) of the E. coli isolates were resistant to at least one antimicrobial. Resistance towards tetracycline was commonly observed (20.7%), whereas resistance to third-generation cephalosporins, fluoroquinolones, and carbapenems was found in 2.2%, 1.4%, and 0.1% of E. coli isolates, respectively. E. coli isolates resistant to two or ≥ 3 antimicrobial classes (MDR) was 2.7% and 15%, respectively. Two multilevel models were built to explore risk factors associated with AMR with AMU being the main exposure. Systemic AMU was associated with increased E. coli resistance. For an increase in systemic AMU equivalent to its IQR, the odds of resistance to any antimicrobial in the model increased by 18%. Fecal samples from calves had higher odds of being resistant to any antimicrobial when compared to other production ages and farm manure storage. The samples collected in 2020 were less likely to be resistant when compared to samples collected in 2019. Compared to previous studies in dairy cattle in North America, AMR in E. coli was lower., Competing Interests: Declaration of Competing Interest The authors declared no conflict of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Campylobacteriosis is one of the most common zoonotic diseases in North America. As opposed to humans, animal infections caused by Campylobacter spp. are often asymptomatic. In this study, data collected through the Canadian Dairy Network for Antimicrobial Stewardship surveillance system were used to determine the proportion of Campylobacter spp. and antimicrobial resistant isolates recovered from dairy cattle herds. Additionally, the association of antimicrobial use (AMU) with fecal carriage and antimicrobial resistance (AMR) of Campylobacter spp. were investigated. Pooled fecal samples from 5 animals from each production phase (pre-weaned calves, post-weaned heifers, lactating cows), and a manure storage sample were collected from 140 dairy herds across Canada. Samples were cultured using selective media, and Campylobacter isolates were speciated using matrix-assisted laser desorption/ionization-time of flight mass spectrometry. Antimicrobial susceptibilities were determined using the minimum inhibitory concentration test, and interpretation was made according to the Clinical and Laboratory Standards Institute. Two multilevel logistic regression models were used to investigate the association between the AMU with the isolation and antimicrobial resistance in Campylobacter spp. Of 560 samples, 63.8% were positive for Campylobacter spp., and 96% of the participating farms had at least one sample source (i.e., calves, heifers, lactating cows, or manure storage) positive for Campylobacter spp. Overall, 54.3% of the Campylobacter spp. isolates were resistant to at least one antimicrobial. Resistance to tetracycline was observed in 49.7% of the Campylobacter spp. isolates, followed by ciprofloxacin (19.9%) and nalidixic acid (19.3%). The proportion of multi-drug resistant (≥3 antimicrobial classes) Campylobacter spp. isolates was low (0.3%); however, 15.6% were resistant to two different classes of antimicrobials. Samples collected from lactating cows, heifers, and manure storage were more likely to be positive for Campylobacter spp. compared to calves. Total AMU was associated with a decreased probability of recovering Campylobacter spp. In addition, AMR to either tetracycline or ciprofloxacin had an interaction with antimicrobial use. The probability of resistance to tetracycline increased for each unit increase in the total AMU (Defined Course Dose/100 animal-years), while the probability of resistance to ciprofloxacin decreased. Campylobacter coli isolates were more likely to be resistant to ciprofloxacin and tetracycline when compared to C. jejuni. Our study demonstrated that Campylobacter spp. is widespread among Canadian dairy farms, and a higher proportion of resistance to tetracycline was identified. The total AMU was associated with increased resistance to tetracycline in Campylobacter spp. isolates; however, for ciprofloxacin the AMU was associated with decreased resistance., Competing Interests: Conflict of Interest The authors declared no conflict of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Widespread overuse of anthelmintics has produced a growing population of intestinal parasites resistant to control measures. A paradigm shift in equine parasite control is warranted to prevent continued resistance development and maintain equine health. Small strongyles, which are ubiquitous in horses, are currently the most important intestinal parasites of adult horses. Sustainable management programs consider the variation in egg shedding by individual horses, and varied risks associated with age, use, density, climate, and environment. To develop regional recommendations for Prince Edward Island (PEI), Canada, it is important to first characterize strongyle egg shedding patterns and parasite management practices in use. Study objectives were to conduct a cross-sectional observational survey and risk factor analysis of parasite control programs, strongyle egg shedding and Strongylus vulgaris serology. A total of 339 horses from 40 PEI farms were sampled. Mean farm size was 8 horses and ranged from 2 to 30. Mean horse age was 11.6 years (Std. Dev. =7.2) and ranged from 2 months to 32 years. Mean fecal egg count (FEC) was 322 eggs per gram (EPG) (Std. Dev. =648). On average, 32% (Std. Dev. =16%) of horses shed 80% of strongyle eggs across 32 eligible farms. When considering all horses (n = 313) as one large herd, 18.7% of horses shed 80% of strongyle eggs. Use of FEC was identified in 4.6% of horses at 15% (n = 6) of PEI farms. Reported deworming intervals included 37.4% (n = 123) every 2-3 months and 58% (n = 191) every 3-4 months. Positive S. vulgaris titers were identified in 60% of horses (n = 200). Univariate analysis revealed that months since last deworming, age, and body condition score (BCS) were associated with strongyle shedding. The estimated odds of being in the high FEC category (>500 EPG) was 1.4 (95% CI, 1.1-1.8) times higher when last deworming increased by one month. Under-conditioned (BCS <4.5) horses had 3.6 (95% CI, 1.2-10.6) times odds of being in the higher FEC category than over-conditioned horses. Non-racing horses had 5.4 times odds of having a positive S. vulgaris titer than racehorses. This cross-sectional observational study is the first to report on the occurrence, risk factors and control of equine strongyle nematode infections in PEI, Canada. We conclude that the 80:20 rule can be used to develop control recommendations in PEI. Very few farms in PEI currently use FEC to guide parasite management. These findings provide a basis for future client education and investigations aimed at providing region specific recommendations., Competing Interests: Declaration of Competing Interest Authors declare no conflict of interest., (Copyright © 2023. Published by Elsevier B.V.)

Teat sealants (TSs) consist of sterile formulations with no antibacterial activity. Alone or in combination with antimicrobial (AM) or non-AM treatments, TSs have been commonly used in dairy cows at dry-off to prevent intra-mammary infections (IMIs) during the dry period. This study aimed to identify and synthesise the available evidence on the efficacy of combining TSs with AM treatments on the incidence and prevalence of IMIs. A comprehensive search of three electronic databases, two relevant conference proceedings, and reference lists of reviews and eligible articles was conducted to retrieve and identify studies that could answer the following question: in dairy cows, how does the efficacy of an AM-TS combination administered at dry-off compare with an AM alone for preventing new IMI? In addition to the general IMIs, bacterial species-specific data were extracted and combined into nine distinct pathogen groups: coagulase-positive and negative staphylococci; S. dysgalactiae; non-dysgalactiae Streptococci; E. coli; non-E. coli Enterobacteriaceae; Corynebacterium spp.; yeast and other frequent mastitis pathogens. The structural relationship between each study's prevalence and incidence, as the new (incidence) and persistent (uncured) infections make up the prevalence, was utilised to approximate a variance-covariance matrix for the within-study correlation between their study-specific log odds ratios (ORs). A bivariate random-effects meta-analysis was employed, utilising the within- and between-study correlations to synthesise both outcomes simultaneously. The risk of bias was assessed using the Cochrane ROBINS-I tool, and the quality of the body of evidence was rated using the GRADE approach. A total of 17 trials (16 studies), providing either IMIs incidence (n = 4), prevalence (n = 3) or both (n = 10), were identified. Overall, quarters infused with AM-TS combinations showed lower odds of new IMIs post-calving (OR=0.70; 95% CI=0.57-0.86; Wald test P < 0.001) than those which received only AMs. Across the pathogen groups, varying levels of reduction of new IMIs were found, where administration of TSs was most effective against S. dysgalactiae (OR=0.47; 95% CI=0.23-0.98), non-dysgalactiae streptococci (OR=0.60; 95% CI=0.49-0.74), E. coli (OR=0.62; 95% CI=0.50-0.77), Corynebacterium spp. (OR=0.68; 95% CI=0.52-0.90) and coagulase-negative staphylococci (OR=0.85; 95% CI=0.76-0.94). However, additional TS infusion did not significantly reduce new IMIs in the remaining pathogen groups. The current meta-analytic evidence supports the efficacy of using TS add-on infusions in dairy cows at dry-off for reducing the incidence and prevalence of IMIs post-calving; however, pathogen group differences should be considered., Competing Interests: Declarations of interest None., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Background: There is currently no commercially available method in Canada to identify bovine leukemia virus (BLV)-positive cows with high proviral load (PVL)., Objectives: First, develop a model to predict PVL using common, commercially available, cost-effective diagnostic tests. Second, investigate the relationship between lymphocyte count and PVL in BLV-positive cows., Animals: A total of 339 BLV-positive and 62 BLV-seronegative cows on 15 dairy farms., Methods: Cross-sectional study. Blood and milk samples were collected from all lactating BLV-positive cows on each farm and 5 to 10 BLV-seronegative cows depending on herd size. Blood and milk samples were tested for anti-BLV antibodies using enzyme-linked immunosorbent assay (ELISA). Complete blood counts were performed on blood samples, and standard components analyses were obtained for milk samples. Proviral load was determined by quantitative polymerase chain reaction for each cow., Results: The inverse of lymphocyte count, the square of the inverse of lymphocyte count, and milk ELISA percent positivity were positively associated with increasing PVL in BLV-positive cows. For BLV-positive cows, lymphocyte count >5.2 × 10 9 /L predicted a high PVL (BLV:Bovine DNA of >1 in blood) with a sensitivity of 92.4% and a specificity of 79.8%. For BLV-positive cows, white blood cell count >10.8 × 10 9 /L predicted a high PVL, with a sensitivity of 85.5% and a specificity of 83.6%., Conclusions and Clinical Importance: Based on these results, producers can implement commonly available diagnostic tests to identify cows with high probability of having high PVL, which may help in designing effective disease control strategies for BLV-positive herds., (© 2022 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals LLC on behalf of American College of Veterinary Internal Medicine.)

Objective: To investigate the effects of dexmedetomidine (DXM) and its subsequent reversal with atipamezole (APM) on the echocardiogram and circulating concentrations of cardiac biomarkers in cats., Animals: 14 healthy cats., Procedures: Cats underwent echocardiography and measurements of circulating cTn-I and NT-proBNP concentrations before (PRE) and during (INTRA) DXM sedation (40 µg/kg IM) and 2 to 4 (2H POST) and 24 (24H POST) hours after reversal with APM., Results: Administering DXM significantly decreased heart rate, right ventricular and left ventricular (LV) outflow tract velocities, and M-mode-derived LV free-wall thickness; increased LV end systolic diameter and volume; and caused valvar regurgitation. While sedative effects resolved within 25 minutes of APM reversal, the evolution of echocardiographic changes was mixed: LV ejection fraction and mitral valvar regurgitation score were different at 2H POST than at both INTRA and PRE (partial return toward baseline), LV end-diastolic volume was different PRE to INTRA and INTRA to 2H POST but not different PRE to 2H POST (full return toward baseline), and M-mode-derived LV free-wall thickness was significantly different from PRE to INTRA and PRE to 2H POST (no return toward baseline). Serum cTn-I and plasma NT-proBNP concentrations increased significantly with DXM, which remained significant 2H POST., Clinical Relevance: Administration of DXM and APM reversal produced changes in echocardiographic results and in circulating cTn-I and NT-proBNP concentrations. Understanding these changes could help veterinarians differentiate drug effects from cardiac disease.

An approximate 1:1 sex ratio of American lobsters can be skewed due to environmental factors or fisheries 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 fishing 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 effect logistic regression model evaluated the effect of spatial, temporal and environmental factors as well as size on the sex ratio of lobsters. There were significant temporal patterns in sex ratios that differed by LFA. After the effects 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 first 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 influenced by environmental factors and fisheries. In view of future climate change scenarios, monitoring the population dynamics of this iconic fishery species is crucial to ensure sustainable fisheries and healthy lobster stocks., (© 2021. The Author(s).)

Introduction: The proliferation of unmanned aerial vehicle (UAV) technology has the potential to change the situational awareness of medical incident commanders' (ICs') scene assessment of mass gatherings. Mass gatherings occur frequently and the potential for injury at these events is considered higher than the general population. These events have generated mass-casualty incidents (MCIs) in the past. The aim of this study was to compare UAV technology to standard practice (SP) in scene assessment using paramedic students during a mass-gathering event (MGE)., Methods: This study was conducted in two phases. Phase One consisted of validation of the videos and accompanying data collection tool. Phase One was completed by 11 experienced paramedics from a provincial Emergency Medical Services (EMS) service. Phase Two was a randomized comparison with 47 paramedic students from the Holland College Paramedicine Program (Charlottetown, Prince Edward Island, Canada) of the two scene assessment systems. For Phase Two, the paramedic students were randomized into a UAV or a SP group. The data collection tool consisted of two board categories: primary importance with 20 variables and secondary importance with 25 variables. After a brief narrative, participants were either shown UAV footage or the ground footage depending on their study group. After completion of the videos, study participants completed the data collection tool., Results: The Phase One validation showed good consensus in answers to most questions (average 79%; range 55%-100%). For Phase Two, a Fisher's exact test was used to compare each variable from the UAV and SP groups using a P value of .05. Phase Two demonstrated a significant difference between the SP and UAV groups in four of 20 primary variables. Additionally, significant differences were found for seven out of 25 secondary variables., Conclusion: This study demonstrated the accurate, safe, and feasible use of a UAV as a tool for scene assessment by paramedic students at an MGE. No observed statistical difference was noted in a majority of both primary and secondary variables using a UAV for scene assessment versus SP.

The objective of this study was to estimate the impact of infestation pressures on the abundance of the parasitic sea louse, Lepeophtheirus salmonis, in the Bay of Fundy, New Brunswick (NB), Canada, using the Fish-iTrends database for the years 2009-2018. Infestation pressures were calculated as time-lagged weighted averages of the abundance of adult female (AF) sea lice within a site (internal infestation pressure: IIP) and among sites (external infestation pressure: EIP). The EIP weights were calculated from seaway distances among sites and a Gaussian kernel density for bandwidths of 5 to 60 km. The EIP with a bandwidth of 10 km had the best fit, as determined with Akaike's information criterion, and historical AF sea lice abundance. This estimated dispersal distance of 10 km was similar to previous studies in Norway, Scotland and in New Brunswick. The infestation pressures estimated from empirical AF sea lice abundance within and among sites significantly increased the abundance of AF sea lice (p < .001). This study concludes that sea lice burdens within Atlantic salmon farms in the Bay of Fundy, NB, are affected by within site management and could be improved by synchronizing treatments between sites., (© 2021 The Authors. Journal of Fish Diseases published by John Wiley & Sons Ltd.)

Introduction: The interpretation of electrocardiograms (ECGs) is an essential competency in modern paramedicine. Although educational guidelines for paramedic ECG interpretation exist, they are broad, not evidence-based, and lack prioritization in a prehospital clinical context. We conducted this study to gain consensus among stakeholders (EMS physicians, paramedic educators, and paramedic clinicians) regarding which ECG diagnoses or findings are most important for a practising advanced care paramedic to know.  Methods: This study was an internet-based Delphi survey. We purposefully sampled participants in pairs (physician/paramedic) from all 10 Canadian provinces. Individuals rated a previously developed comprehensive list of emergency ECG diagnoses or findings on the importance of paramedic recognition and impact on prehospital care using a 4-point Likert scale. The consensus was achieved with a minimum of 75% agreement on Likert rating for a single diagnosis or finding during survey rounds one to three. When consensus was not reached, stability was defined as a shift of individual ratings between rounds of 20% or less., Results: All 20 participants completed the first and second rounds of the survey, and 17 (85%) completed three rounds. Overall, 32 (26.4%) of 121 potentially important ECG diagnoses or findings reached consensus, 2 (1.7%) reached stability and 87 (71.9%) reached neither consensus nor stability. Twenty-one (17.4%) diagnoses or findings were considered "Very Important", six (4.9%) "Important", and five (4.1%) "Minimally Important". In the first round of the survey, the mean rating of the importance of a paramedic knowing a specific ECG diagnosis or finding was lower in the physician group than the paramedic group on 85 (72%) of 118 initial diagnoses or findings., Conclusion: We have created a list of ECG diagnoses or findings prioritized for the prehospital context that may assist paramedic educators in focusing on educational interventions. Many ECG diagnoses or findings failed to reach consensus or stability, demonstrating potential disagreement regarding clinical expectations for ECG knowledge among paramedics or physicians., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2021, Sibley et al.)

Co-cultivation has been used as a promising tool to turn on or up-regulate cryptic biosynthetic pathways for microbial natural product discovery. Recently, a modified culturing strategy similar to co-cultivation was investigated, where heat-killed inducer cultures were supplemented to the culture medium of producer fermentations to induce cryptic pathways. In the present study, the repeatability and effectiveness of both methods in turning on cryptic biosynthetic pathways were unbiasedly assessed using UHPLC-HRESIMS-based metabolomics analysis. Both induction methods had good repeatability, and they resulted in very different induced metabolites from the tested producers. Co-cultivation generated more induced mass features than the heat-killed inducer cultures, while both methods resulted in the induction of mass features not observed using the other induction method. As examples, pathways leading to two new natural products, N -carbamoyl-2-hydroxy-3-methoxybenzamide ( 1 ) and carbazoquinocin G ( 5 ), were induced and up-regulated through co-culturing a producer Streptomyces sp. RKND-216 with inducers Alteromonas sp. RKMC-009 and M. smegmatis ATCC 120515, respectively.

Over the past 30 yr, the prevalence of bovine leukemia virus (BLV) infection has increased in North America, including Atlantic Canada, at both the herd and individual cow levels. This has occurred despite increased awareness of the disease and its deleterious effects and despite implementation of management practices aimed at reducing disease transmission. Our objectives were to identify risk factors associated with the within-herd prevalence of BLV-infected cows by using a risk assessment and management program workbook, as well as to determine the current level of BLV prevalence in the Atlantic Canada region. We hypothesized that previously established risk factors, including management practices associated with calf rearing and fly control, would affect within-herd BLV prevalence. Bulk tank milk (BTM) samples were collected in January and April of 2016 and again during the same months in 2017 and 2018 from all dairy farms shipping milk in the region. Samples were tested with ELISA for levels of anti-BLV antibodies to estimate within-herd prevalence. Regional BLV prevalence at the herd level was 88.39% of dairy herds infected in 2016 and 89.30% in 2018. All dairy farms shipping milk and who had BTM samples collected in 2017 (n = 605) were eligible to participate in the risk assessment and management program questionnaire (RAMP), which was developed and distributed to all bovine veterinarians in Atlantic Canada. One hundred and six RAMP were returned, with representation from all 4 provinces. The RAMP results were combined with the mean BTM ELISA results, and univariable logistic regression followed by multivariable logistic regression was performed to investigate the association between RAMP risk factors and the estimated within-herd BLV prevalence. Factors in the multivariable model significantly associated with the odds of a herd being classified as >25% estimated within-herd prevalence included history of diagnosis of clinical BLV and calves receiving colostrum from cows with unknown BLV status. Differences in within-herd prevalence were not associated with hypodermic needle and injection practices, rectal sleeve practices, or using bulls for natural breeding, based on these 106 dairy farms., (Copyright © 2020 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)

Objective: The aim of this study was to determine the relationship between milk urea nitrogen (MUN) and reproductive performance in dairy cows in western Thailand., Design: All cows calving from November 2014 to April 2015 were included in the study, a total of 486 cows from 47 farms. Each cow had milk constituents and MUN tested monthly up to confirmed conception or until the 8th month after parturition. Each farm had a dietary assessment completed. Cox proportional hazard models with shared frailty were used to determine associations of conception rate., Results: Cows became pregnant increasingly quickly over time, except during 100-150 days of lactation. A change in MUN from 12.5 to 13.5 mg/dL on the closet day to breeding was associated with a 5% decrease in conception. Milk protein was negatively associated with hazard of conception, whereas milk lactose and dietary protein:energy ratio had positive associations with conception rate. Breeding season was also significant; the highest conception rate was observed in cows inseminated during winter, whereas insemination during the humid rainy season resulted in the lowest conception rates. The farm random effect in the model was strongly significant., Conclusion: Detrimental effects of higher MUN on rate of conception were identified. The rate of conception was positively associated with protein:energy ratio in the study. Therefore, good nutritional management leading to positive energy balance should benefit conception rates., (© 2020 Australian Veterinary Association.)

The objective of this observational cohort study was to identify management factors associated with lamb mortality risk for sheep flocks in Prince Edward Island, Canada. Data were collected from 50 lambing groups from 36 sheep flocks during 3 farm visits before, during and after the lambing seasons in 2014-15. Variables of interest included flock management practices, ewe health indicators, ewe nutrition, litter size and lamb birth weight. Principal component analysis was performed and resulting component scores were used for further analysis using a mixed Poisson regression model with lamb mortality risk as the outcome. The median group-level lamb mortality in the first 8 weeks of life was 10.0 % (0 %-30.3 %), with 25 groups having lamb mortality greater than 10 %, which is considered higher than the standard productivity goal. Four principal component scores were retained in the final model identifying generalized factors associated with lamb mortality: 1) flock factors, 2) forage factors, 3) lamb health factors, and 4) general health factors. Specifically, the following management factors were indirectly through the 4 principal components associated with lower lamb mortality: using goal setting; having a strong working relationship with a veterinarian; seeking veterinary advice for animal treatment; using benzimidazole-class anthelmintics; feeding forage with high crude protein, digestible energy, and net energy for maintenance and low acid detergent fiber to late-gestation ewes; applying visual lamb identification methods; using anti-coccidial prophylactic medication to lambs; administering clostridial vaccines to lambs; avoiding separation of hypothermic lambs from their dams; and treatment/prevention of neurological and/or wasting disease. Although this study is exploratory, and confirmation is required, the results should help sheep farmers and researchers direct attention to management variables that could reduce lamb mortality in sheep flocks., Competing Interests: Declaration of Competing Interest None., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Sea lice are ectoparasites of salmonids, and are considered to be one of the main threats to Atlantic salmon farming. Sea lice infestation on a farm is usually initiated by attachment of the free-living copepodid stage derived from the surrounding water, frequently originating from adult lice on the same farm or from neighboring salmonid farms, referred to as internal and external sources, respectively. Various approaches have been proposed to quantify sea lice infestation pressure on farms to improve the management of this pest. Here, we review and compare five of these methods based on sea lice data from 20 farms located near Grand Manan island in the Bay of Fundy, New Brunswick, Canada. Internal and external infestation pressures (IIP and EIP, respectively) were estimated using different approaches, and their effects were modeled either by a unique parameter for all production cycles or by different parameters for each production cycle, using a multivariate state-space model. Predictive variables, such as water temperature and sea lice treatments, were included in the model, and their effects across production cycles were estimated along with those of other model parameters. Results showed that models with only EIP explained the variation in the data better than models with only IIP, and that models with unique IIP and unique EIP for all cycles were generally associated with the best model fit. The simplest, fixed lag method for calculating infestation pressure had the best predictive performance in our models among the methods studied., Competing Interests: Declaration of Competing Interest The authors have no conflicts of interest to declare., (Copyright © 2020. Published by Elsevier B.V.)

Bacterial Kidney Disease (BKD) is an economically significant disease in salmonid aquaculture and commonly requires antibiotic treatments to reduce its impact. Once a pen of fish is diagnosed with BKD, fish are considered chronically infected, potentially until harvest. Although there appears to be little or no evidence to support it, it is often assumed that subclinical infections affect productivity over the long term. We used a 2-stage hierarchical interrupted time series (ITS) analysis in an attempt to quantify the effect of subclinical BKD on mortality, growth, and food conversion ratio (FCR) of Atlantic salmon cultured in marine farms in Atlantic Canada. For all three outcomes, BKD had for some site cycles a positive effect, and for others a negative effect. Overall, the effect of BKD on mortality and growth could not be detected (effect -0.08 ((95% ci: -0.51, 0.35) and 0.00 (-0.02, 0.02)), while a very small effect showing an increase in FCR was detected (0.07 (-0.01, 0.15)). We hypothesized that minimal interference with fish performance may be compatible with the ecology of Renibacterium salmoninarum, the causative agent of BKD. For this organism, vertical transmission is a primary mode of propagation in low-density host populations as found in the wild. Since farms are always adapting and optimizing their farm management of BKD, these constant adjustments may also have negated our ability to detect the effect of many factors contributing to BKD productivity impacts. Hierarchical ITS analysis is considered an appropriate methodology to investigate the complex relationships with productivity measures over time under farming conditions. In the highly innovative salmon aquaculture industry, health records generating data available for time-series analysis is expected to become more accurate and abundant in the future, providing more opportunities for time-series regression studies., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Reliable assessment of the susceptibility of animal bacterial pathogens to antimicrobials is of paramount importance in the fight against antimicrobial resistance. This work aims to estimate the repeatability (intra-laboratory agreement) and reproducibility (inter-laboratory agreement) of the disc diffusion assay in veterinary laboratories to understand further if the assay has a role in the surveillance of antimicrobial resistance in animals. Seven major veterinary laboratories from all States in Australia participated, and each tested the same panel of isolates five times at three to four-week intervals, against six antimicrobial agents using Clinical and Laboratory Standards Institute protocols. The panel consisted of twenty different isolates from porcine Escherichia coli from clinical cases and a single reference strain (ATCC 25922). Laboratories were blinded to the identity of the isolates, replicates, and to each other. In total, 4200 inhibition zone diameters (mm) were collected, and analysed descriptively, graphically, and with linear mixed models. Regardless of the laboratories and isolate/antimicrobial combinations, the overall very major error rate (proportion of isolates classified as susceptible when actual status is resistant) was 1.6%; the major error rate (proportion of isolates classified as resistant when actual status is susceptible) was 1.6%; and the 'minor error' rate (proportion of isolates with intermediate susceptibility that measure fully susceptible or resistant or vice versa) was 2.4%. The variation between repeated measurements ranged between 4.4-7.2 mm depending on the antimicrobial agent assessed. The reproducibility was always more variable than the repeatability, which suggested some laboratory effects. The repeatability coefficient of disc diffusion was lowest for tetracycline (4.4 mm, 95% CI: 3.8-5.0 mm) and ampicillin (4.6 mm, 95% CI: 4.2-5.2 mm) and highest for trimethoprim-sulfamethoxazole (6.6 mm, 95% CI: 5.9-7.4 mm). The reproducibility coefficient of disc diffusion was lowest for gentamicin (5.4, 95% CI: 4.0-7.2) and highest for trimethoprim-sulfamethoxazole (7.2 mm, 95%CI: 4.5-11.7 mm). The precision of the disc diffusion assay was deemed satisfactory for use in a national surveillance program for clinical porcine E. coli isolates. However, measurement variation of the disc diffusion assay is of concern for isolates with marginal susceptibility or resistance due to increased risk of misclassification., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Background: A small proportion of the population consumes the majority of health care resources. High-cost health care users are a heterogeneous group. We aim to segment a provincial population into relevant homogenous sub-groups to provide actionable information on risk factors associated with high-cost health care use within sub-populations., Methods: The Canadian Institute for Health Information (CIHI) Population Grouping methodology was used to define mutually exclusive and clinically relevant health profile sub-groups. High-cost users (> = 90th percentile of health care spending) were defined within each sub-group. Univariate analyses explored demographic, socio-economic status, health status and health care utilization variables associated with high-cost use. Multivariable logistic regression models were constructed for the costliest health profile groups., Results: From 2015 to 2017, 1,175,147 individuals were identified for study. High-cost users consumed 41% of total health care resources. Average annual health care spending for individuals not high-cost were $642; high-cost users were $16,316. The costliest health profile groups were 'long-term care', 'palliative', 'major acute', 'major chronic', 'major cancer', 'major newborn', 'major mental health' and 'moderate chronic'. Both 'major acute' and 'major cancer' health profile groups were largely explained by measures of health care utilization and multi-morbidity. In the remaining costliest health profile groups modelled, 'major chronic', 'moderate chronic', 'major newborn' and 'other mental health', a measure of socio-economic status, low neighbourhood income, was statistically significantly associated with high-cost use., Interpretation: Model results point to specific, actionable information within clinically meaningful subgroups to reduce high-cost health care use. Health equity, specifically low socio-economic status, was statistically significantly associated with high-cost use in the majority of health profile sub-groups. Population segmentation methods, and more specifically, the CIHI Population Grouping Methodology, provide specificity to high-cost health care use; informing interventions aimed at reducing health care costs and improving population health.

Background: Fine-needle aspiration (FNA) is a common procedure as a diagnostic tool in veterinary medicine. However, it is unclear whether the gauge of the needle affects the quality of cytology., Objective: This study compared the quality of cytologic samples obtained via FNA using 22- or 25-gauge needles., Methods: Fine-needle aspiration was performed on 50 masses (cutaneous, subcutaneous, or intracavitary) obtained from client-owned animals. The size of the needle was randomly assigned using either of the following two sequences: 22-25-22 gauge or 25-22-25 gauge. Samples were evaluated by two board-certified clinical pathologists to assess cellularity, blood contamination, amount of cellular debris, degree of cellular trauma, and the overall ability to make a diagnosis for each sample., Results: No significant difference was detected between the 22- and 25-gauge needle samples for cellularity, whereas a significant difference was present for blood contamination, amount of cellular debris, and degree of cellular trauma. The overall ability to make a diagnosis was not significantly affected by the needle gauge. The degree of cellular trauma was significantly increased in intracavitary samples., Conclusions and Clinical Relevance: Needle gauge is a contributing factor to FNA sample quality. However, it did not affect the overall ability to make a diagnosis. Samples obtained using 25-gauge needles resulted in less blood contamination yet increased cellular trauma compared to 22-gauge needle samples., (© 2019 American Society for Veterinary Clinical Pathology.)

The parasitic salmon louse constrains growth in the Norwegian salmon farming industry through density dependent host-parasite interaction. Hence, there is a need for insight into how increases in salmon production, varying spatial organisation of the production and pest control strategies affect salmon louse population dynamics. Here we present a new salmon louse model for exploring effects of varying salmon farming conditions on spatio-temporal abundances of the parasite. The salmon louse model is partly stage-structured, comprising of (i) adult female lice and (ii) other mobile stages of lice. The abundance of adult females depend on survival of females from previous weeks and recruitment from the other mobile group of lice. The other mobiles also depend on survival of other mobiles from previous weeks, as well as recruitment from the previous generation of reproducing adult females from the same farm or from farms in the neighbourhood. In addition, expected abundances of the two stage-groups are modelled as functions of biological and physical covariates. The model is fitted to weekly salmon farm data covering all marine farms producing salmonids along the Norwegian cost over the years 2012-2016. Among novel results from fitting the model are estimates of the time-lag structure representing recruitment of other mobile lice from the previous generation adult females for different temperatures. Furthermore, the model estimates how various factors affect the susceptibility of fish on farms to louse infection and effects of treatments to control infection. Finally, the model estimates density dependent effects of increasing the number of fish in farms and of increasing the numbers of farms, on the rate of recruitment of other mobile lice. Analytically, the parameters representing density dependencies suggest that few farms with many fish and large between farm distances is effective in terms of minimising the overall output of salmon lice infection., (Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.)

Undetected injury of horses sustained during road transport to slaughter is a welfare concern. This study evaluated digital infrared thermography (DT) for the detection of ante-mortem bruising in horses following transport to a slaughter plant. The sensitivity and specificity of DT for the detection of bruises following transport was evaluated. DT images were obtained from 93 horses (2-3 horses per load; 40 loads) at a Canadian federally approved slaughter plant. From an elevated platform 5 m from the horses, left and right lateral DT images, and one caudal pelvic area image were obtained from each horse. After slaughter the carcasses were examined for bruising (a visually discolored area on the carcass caused by damage to the blood vessels) and findings documented. Sensitivity, specificity, and predictive values were calculated for DT assessment of bruising. The prevalence of bruising on post mortem inspection was 54%. The DT approach to bruise detection at the region of interest level of 93 horses ( n = 186 sides) resulted in a sensitivity of 42% and specificity of 79%. As the sensitivity was low, a more sensitive DT camera and allowing for a longer equilibration time for horses after transport may improve this approach to post transport assessment of subclinical injury.

Objective: A small proportion of the population accounts for the majority of healthcare costs. Mental health and addiction (MHA) patients are consistently high-cost. We aimed to delineate factors amenable to public health action that may reduce high-cost use among a cohort of MHA clients in Saskatoon, Saskatchewan., Methods: We conducted a population-based retrospective cohort study. Administrative health data from fiscal years (FY) 2009-2015, linked at the individual level, were analyzed (n = 129,932). The outcome of interest was ≥ 90th percentile of costs for each year under study ('persistent high-cost use'). Descriptive analyses were followed by logistic regression modelling; the latter excluded long-term care residents., Results: The average healthcare cost among study cohort members in FY 2009 was ~ $2300; for high-cost users it was ~ $19,000. Individuals with unstable housing and hospitalization(s) had increased risk of persistent high-cost use; both of these effects were more pronounced as comorbidities increased. Patients with schizophrenia, particularly those under 50 years old, had increased probability of persistent high-cost use. The probability of persistent high-cost use decreased with good connection to a primary care provider; this effect was more pronounced as the number of mental health conditions increased., Conclusion: Despite constituting only 5% of the study cohort, persistent high-cost MHA clients (n = 6455) accounted for ~ 35% of total costs. Efforts to reduce high-cost use should focus on reduction of multimorbidity, connection to a primary care provider (particularly for those with more than one MHA), young patients with schizophrenia, and adequately addressing housing stability.

Caligus rogercresseyi is a host-dependent parasite that affects rainbow trout and Atlantic salmon in Chile. Numbers of sea lice on fish increase over time at relatively predictable rates when the environment is conducive to the parasite's survival and fish are not undergoing treatment. We developed a tool for the salmon industry in Chile that predicts the abundance of adult sea lice over time on farms that are relatively isolated. We used data on sea louse abundance collected through the SalmonChile INTESAL sea lice monitoring program to create series of weekly lice counts between lice treatment events on isolated farms. We defined isolated farms as those with no known neighbors within a 10 km seaway distance and no more than two neighbors within a 20 km seaway distance. We defined the time between sea lice treatments as starting the week immediately post treatment and ending the week before a subsequent treatment. Our final dataset of isolated farms consisted of 65 series from 32 farms, between 2009 and 2015. Given an observed abundance at time t = 0, we built a model that predicted 8 consecutive weekly sea louse abundance levels, based on the preceding week's lice prediction. We calibrated the parameters in our model on a randomly selected subset of training data, choosing the parameter combinations that minimized the absolute difference between the predicted and observed sea louse abundance values. We validated the parameters on the remaining, unseen, subset of data. We encoded our model and made it available as a Web-accessible applet for producers. We determined a threshold, based on the upper 97.5% predictive interval, as a guideline for producers using the tool. We hypothesize that if farms exceed this threshold, especially if the sea lice levels are above this threshold 2 and 4 weeks into the model predictions, the sea louse population on the farm is likely influenced by sources other than lice within the farm., (Copyright © 2018 Elsevier B.V. All rights reserved.)

IntroductionThe proliferation of unmanned aerial vehicles (UAV) has the potential to change the situational awareness of incident commanders allowing greater scene safety. The aim of this study was to compare UAV technology to standard practice (SP) in hazard identification during a simulated multi-vehicle motor collision (MVC) in terms of time to identification, accuracy and the order of hazard identification., Methods: A prospective observational cohort study was conducted with 21 students randomized into UAV or SP group, based on a MVC with 7 hazards. The UAV group remained at the UAV ground station while the SP group approached the scene. After identifying hazards the time and order was recorded., Results: The mean time (SD, range) to identify the hazards were 3 minutes 41 seconds (1 minute 37 seconds, 1 minute 48 seconds-6 minutes 51 seconds) and 2 minutes 43 seconds (55 seconds, 1 minute 43 seconds-4 minutes 38 seconds) in UAV and SP groups corresponding to a mean difference of 58 seconds (P=0.11). A non-parametric permutation test showed a significant (P=0.04) difference in identification order., Conclusion: Both groups had 100% accuracy in hazard identification with no statistical difference in time for hazard identification. A difference was found in the identification order of hazards. (Disaster Med Public Health Preparedness. 2018;12:631-634).

Sea lice are marine parasites affecting salmon farms, and are considered one of the most costly pests of the salmon aquaculture industry. Infestations of sea lice on farms significantly increase opportunities for the parasite to spread in the surrounding ecosystem, making control of this pest a challenging issue for salmon producers. The complexity of controlling sea lice on salmon farms requires frequent monitoring of the abundance of different sea lice stages over time. Industry-based data sets of counts of lice are amenable to multivariate time-series data analyses. In this study, two sets of multivariate autoregressive state-space models were applied to Chilean sea lice data from six Atlantic salmon production cycles on five isolated farms (at least 20 km seaway distance away from other known active farms), to evaluate the utility of these models for predicting sea lice abundance over time on farms. The models were constructed with different parameter configurations, and the analysis demonstrated large heterogeneity between production cycles for the autoregressive parameter, the effects of chemotherapeutant bath treatments, and the process-error variance. A model allowing for different parameters across production cycles had the best fit and the smallest overall prediction errors. However, pooling information across cycles for the drift and observation error parameters did not substantially affect model performance, thus reducing the number of necessary parameters in the model. Bath treatments had strong but variable effects for reducing sea lice burdens, and these effects were stronger for adult lice than juvenile lice. Our multivariate state-space models were able to handle different sea lice stages and provide predictions for sea lice abundance with reasonable accuracy up to five weeks out., (Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.)

IntroductionThe proliferation of unmanned aerial vehicle (UAV) technology has the potential to change the way medical incident commanders (ICs) respond to mass-casualty incidents (MCIs) in triaging victims. The aim of this study was to compare UAV technology to standard practice (SP) in triaging casualties at an MCI., Methods: A randomized comparison study was conducted with 40 paramedic students from the Holland College Paramedicine Program (Charlottetown, Prince Edward Island, Canada). Using a simulated motor vehicle collision (MVC) with moulaged casualties, iterations of 20 students were used for both a day and a night trial. Students were randomized to a UAV or a SP group. After a brief narrative, participants either entered the study environment or used UAV technology where total time to triage completion, GREEN casualty evacuation, time on scene, triage order, and accuracy were recorded., Results: A statistical difference in the time to completion of 3.63 minutes (95% CI, 2.45 min-4.85 min; P=.002) during the day iteration and a difference of 3.49 minutes (95% CI, 2.08 min-6.06 min; P=.002) for the night trial with UAV groups was noted. There was no difference found in time to GREEN casualty evacuation, time on scene, or triage order. One-hundred-percent accuracy was noted between both groups., Conclusion: This study demonstrated the feasibility of using a UAV at an MCI. A non-clinical significant difference was noted in total time to completion between both groups. There was no increase in time on scene by using the UAV while demonstrating the feasibility of remotely triaging GREEN casualties prior to first responder arrival.Jain T, Sibley A, Stryhn H, Hubloue I.Comparison of unmanned aerial vehicle technologyassisted triage versus standard practice in triaging casualties by paramedic students in a mass-casualty incident scenario. Prehosp Disaster Med. 2018;33(4):375-380.

Synthetic pyrethroids have been widely used in Chile to control the sea lice Caligus rogercresseyi, a major ectoparasite of farmed salmon. Although resistance of C. rogercresseyi to pyrethroids has been reported in Chile, there is no information regarding the geographic extent of this problem. In this study we explored the spatial and temporal variation of C. rogercresseyi's response to pyrethroids in Chile from 2012 to 2013. We modeled lice abundance one week after treatment with a linear mixed-effects regression, and then we performed spatial and spatio-temporal cluster analyses on farm-level effects and on treatment-level residuals, respectively. Results indicate there were two areas where the post-treatment lice counts were significantly higher than in the rest of the study area. These spatial clusters remained even once we adjusted for environmental and management predictors, suggesting unmeasured factors (e.g. resistance) were causing the clustering. Further investigation should be carried out to confirm this hypothesis., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

In dairy herds, application of antimicrobials at drying-off is a common mastitis control measure. This article describes a protocol for systematic review and meta-analysis to address three crucial points regarding antimicrobial usage at drying-off: (1) comparative efficacy of antimicrobials used for preventing new and eliminating existing intramammary infections (IMI); (2) comparison of selective and blanket dry cow therapy approaches in preventing new and eliminating existing IMI; and (3) assessment of the extra prevention against new IMI that can be gained from using antimicrobial-teat sealant combinations versus antimicrobials alone. Five PICO (Population, Intervention, Comparator, Outcome) questions were formulated to cover the three objectives of the review. Medline, CAB Abstracts, Web of Science, and conference proceedings will be searched along with iterative screening of references. Articles will be eligible if: (1) published after 1966; (2) written in English or French; and (3) reporting field clinical trials and observational studies, conducted on dairy cows at drying-off, with at least one antimicrobial-treated group and one IMI-related outcome. Authors will independently assess the relevance of titles and abstracts, extract data, and assess bias and the overall quality of evidence. Results will be synthesized and analyzed using pairwise and network meta-analysis. The proposed study will significantly update previously conducted reviews.

Bulk tank milk (BTM) samples are used to determine the infection status and estimate dairy herd prevalence for bovine leukaemia virus (BLV) using an antibody ELISA assay. BLV ELISA variability between samples from the same herd or from different herds has not been investigated over long time periods. The main objective of this study was to determine the within-herd and between-herd variability of a BTM BLV ELISA assay over 1-month, 3-month, and 3-year sampling intervals. All of the Canadian Maritime region dairy herds (n = 523) that were active in 2013 and 2016 were included (83.9% and 86.9% of total herds in 2013 and 2016, respectively). BLV antibody levels were measured in three BTM samples collected at 1-month intervals in early 2013 as well as two BTM samples collected over a 3-month interval in early 2016. Random-effects models, with fixed effects for sample replicate and province and random effects for herd, were used to estimate the variability between BTM samples from the same herd and between herds for 1-month, 3-month, and 3-year sampling intervals. The majority of variability of BTM BLV ELISA results was seen between herds (1-month, 6.792 ± 0.533; 3-month, 7.806 ± 0.652; 3-year, 6.222 ± 0.528). Unexplained variance between samples from the same herd, on square-root scale, was greatest for the 3-year (0.976 ± 0.104), followed by the 1-month (0.611 ± 0.035) then the 3-month (0.557 ± 0.071) intervals. Variability of BTM antibody levels within the same herd was present but was much smaller than the variability between herds, and was greatest for the 3-year sampling interval. The 3-month sampling interval resulted in the least variability and is appropriate to use for estimating the baseline level of within-herd prevalence for BLV control programs. Knowledge of the baseline variability and within-herd prevalence can help to determine effectiveness of control programs when BTM sampling is repeated at longer intervals., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Clinical mastitis (CM) is one of the most frequent and costly diseases in dairy cows. A frustrating aspect of CM is its recurrent nature. This review was conducted to synthesize knowledge on risk of repeated cases of CM, effects of recurrent CM cases, and risk factors for CM recurrence. A systematic review methodology was used to identify articles for this narrative review. Searches were performed to identify relevant scientific literature published after 1989 in English or French from 2 databases (PubMed and CAB Abstracts) and 1 search platform (Web of Science). Fifty-seven manuscripts were selected for qualitative synthesis according to the inclusion criteria. Among the 57 manuscripts selected in this review, a description of CM recurrence, its risk factors, and effects were investigated and reported in 33, 37, and 19 selected manuscripts, respectively. Meta-analysis and meta-regression analyses were used to compute risk ratio comparing risk of CM in cows that already had 1 CM event in the current lactation with risk of CM in healthy cows. For these analyses, 9 manuscripts that reported the total number of lactations followed and the number of lactations with ≤1 and ≤2 CM cases were used. When summarizing results from studies requiring ≥5 d between CM events to consider a CM event as a new case, we observed no significant change in CM susceptibility following a first CM case (risk ratio: 0.99; 95% confidence interval: 0.86-1.14). However, for studies using a more liberal CM recurrence definition (i.e., only 24 h between CM events to consider new CM cases), we observed a 1.54 times greater CM risk (95% confidence interval: 1.20-1.97) for cows that already had 1 CM event in the current lactation compared with healthy cows. The most important risk factors for CM recurrence were parity (i.e., higher risk in older cows), a higher milk production, pathogen species involved in the preceding case, and whether a bacteriological cure was observed following the preceding case. The most important effects of recurrent CM were the milk yield reduction following a recurrent CM case, which was reported to be similar to that of the first CM case, and the increased risk of culling and mortality, which were reported to surpass those of first CM cases., (Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)

Aim: The study was to determine seasonal fluctuations and non-nutritional factors associated with bulk tank milk urea nitrogen(BTMUN)., Materials and Methods: A total of 58,364 BTM testing records were collected from 2364 farms in Central Thailand during September 2014-August 2015. Using square root BTMUN as the outcome, other milk components, farm effect, and sampling time were analyzed by univariable repeated measures linear regression, and significant variables were included in multivariable repeated measures linear regression., Results: The average BTMUN (standard deviation) was 4.71 (±1.16) mmol/L. In the final model, BTM fat and protein percentages were associated with BTMUN as quadratic and cubic polynomials, respectively. BTM lactose percentage and the natural logarithm of somatic cell counts were negatively linearly associated with BTMUN. At the farm level, the BTM lactose association was negatively linear; herd BTMUN decreased following an increase of herd lactose average, and BTM lactose slopes were quite different among farms as well. Sampling time had the highest potency for the estimation of BTMUN over time, with lows and highs occurring in August and October, respectively. The variation in test level BTMUN was decreased by 18.6% compared to the null model, and 6% of the variance could be explained at the farm level., Conclusion: The results clarify seasonal variation in BTMUN and the relationships among other BTM constituents and BTMUN, which may be useful for understanding how to manage lactating dairy cattle better to keep BTM constituents within normal ranges.

Multilevel data occur frequently in many research areas like health services research and epidemiology. A suitable way to analyze such data is through the use of multilevel regression models. These models incorporate cluster-specific random effects that allow one to partition the total variation in the outcome into between-cluster variation and between-individual variation. The magnitude of the effect of clustering provides a measure of the general contextual effect. When outcomes are binary or time-to-event in nature, the general contextual effect can be quantified by measures of heterogeneity like the median odds ratio or the median hazard ratio, respectively, which can be calculated from a multilevel regression model. Outcomes that are integer counts denoting the number of times that an event occurred are common in epidemiological and medical research. The median (incidence) rate ratio in multilevel Poisson regression for counts that corresponds to the median odds ratio or median hazard ratio for binary or time-to-event outcomes respectively is relatively unknown and is rarely used. The median rate ratio is the median relative change in the rate of the occurrence of the event when comparing identical subjects from 2 randomly selected different clusters that are ordered by rate. We also describe how the variance partition coefficient, which denotes the proportion of the variation in the outcome that is attributable to between-cluster differences, can be computed with count outcomes. We illustrate the application and interpretation of these measures in a case study analyzing the rate of hospital readmission in patients discharged from hospital with a diagnosis of heart failure., (© 2017 The Authors. Statistics in Medicine published by John Wiley & Sons Ltd.)

Methicillin-resistant Staphylococcus pseudintermedius (MRSP) has emerged as a major pathogen in dogs and has been implicated as a hospital-acquired pathogen in veterinary hospitals. We attempted to determine if selective culture methods will detect more MRSP when compared to the traditional culture methods in clinical samples from dogs in Atlantic Canada with a high risk for MRSP infection. Each sample was tested using 4 culture methods: traditional culture; mannitol salt agar with 2 μg/mL of oxacillin (MSAox); enrichment broth (EB) with MSAox; and EB with traditional culture. Detection of penicillin-binding protein 2', via latex agglutination, was used as a confirmatory test for oxacillin resistance. We analyzed 741 samples from 556 dogs between February 2013 and April 2014. The prevalence of MRSP in samples detected by any method was estimated at 13.4% (95% CI: 11.1-16.0%). When the prevalence of MRSP was determined according to culture method, EB with MSAox detected the highest prevalence (11.2% [9.1-13.7%]), followed by EB with traditional (10.8% [8.8-13.2%]), traditional (10.1% [8.1-12.5%]), and MSAox (8.9% [7.1-11.2%]). The prevalence using the traditional culture method did not differ significantly from any of the 3 selective culture methods. Culture with MSAox detected significantly fewer MRSP than either of the EB methods. The addition of EB to current methodology is recommended, particularly for patients considered at high risk for MRSP infection.

Infection with Renibacterium salmoninarum, the cause of Bacterial Kidney Disease (BKD) occurs in salmon populations in many locations, including the east coast of Canada. However, information about risk factors for BKD and their effects in the saltwater phase of the salmon aquaculture industry in the region is inadequate. We conducted a retrospective observational cohort study using industry health records in which BKD was recorded in New Brunswick, Canada, between 2006 and 2012. Several risk factors for BKD, such as stocking season, mortality percentage in the first four weeks, food conversion ratio (FCR), lice treatment, Bay Management Area (BMA), and production year were analyzed in a survival analysis using Cox proportional hazards models with cross-classified random effects to account for the structure of the data. The models incorporated effects on two different time scales, time since stocking and calendar time. The risk period was from stocking in salt water to first occurrence of clinical BKD in a pen. Results were time varying. Stocking season had a pronounced effect on time to clinical BKD after middle October of the first year after stocking, with clinical cases occurring less frequently in fall/winter-stocked fish compared to summer and spring-stocked fish; for example, in middle October, the Hazard Ratio of spring- compared to fall/winter-stocked fish was 15.8 (95% CI; 1.05, 354). Differences lasted until June and July of the second year after stocking. Effects of final hatchery before transfer to seawater, and egg source were not detected, but a limitation of this study was that this information was not available for 44.3% of the fish groups in our dataset. BKD status of a site/pen before fallow period and distance to nearest site with BKD were also not detected. Feed conversion ratio and mortality during the first four weeks affected BKD, indicating that better performing fish have a reduced hazard for BKD or vice versa, and implying that good general husbandry practices and BKD are correlated., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Choices made by cats between different types of environmental enrichment may help shelters to prioritize how to most effectively enrich cat housing, especially when limited by space or funds. This study investigates the environmental enrichment use of cats in a choice test. Twenty-six shelter cats were kept singularly in choice chambers for 10days. Each chamber had a central area and four centrally-linked compartments containing different types of environmental enrichment: 1) an empty control, 2) a prey-simulating toy, 3) a perching opportunity, and 4) a hiding opportunity. Cat movement between compartments was quantitatively recorded using a data-logger. Enriched compartments were visited significantly more frequently during the light period than during the dark period. Cats spent a significantly greater percentage of time in the hiding compartment (median=55%, IQR=46) than in the toy compartment (median=2%, IQR=9), or in the empty control compartment (median=4%, IQR=4). These results provide additional evidence to support the value of a hiding box to cats housed in a novel environment, in that they choose hiding relative to other types of environmental enrichment., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Evidence suggests that rabies vaccine may have non-specific protective effects in animals and children. We analyzed four years of data (2012-2015) from an observational study of the health and demographics of a population of owned, free-roaming dogs in a low-income community in South Africa. The objective of this analysis was to assess the association between rabies vaccine and all-cause mortality in dogs, stratified by age group (0-3months, 4-11months, and 12months and older), and controlling for the effects of sex and number of dogs in the residence. Rabies vaccination reduced the risk of death from any cause by 56% (95% CI=16-77%) in dogs aged 0-3months, by 44% (95% CI=21-60%) in dogs aged 4-11months and by 16% (95% CI=0-29%) in dogs aged 12months and older. We hypothesize that the protective association between rabies vaccination status and all-cause mortality is due to a protective effect of rabies vaccine against diseases other than rabies. Existence of a strong non-specific protective effect of rabies vaccine on mortality in dogs would have implications for the design of dog rabies control programs that aim to eliminate dog-mediated human rabies cases. Further, we propose that owned domestic dogs in high mortality settings provide a useful animal model to better understand any non-specific protective effect of rabies vaccine in children, due to dogs' high numbers, high morbidity and mortality rates, relatively short lifespan, exposure to a variety of infectious and parasitic diseases, and shared environment with people., (Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.)