Trends in companion animal access to veterinary care in Canada, 2007 to 2020.

Objective: Assess trends in access to veterinary care for companion animals in Canada. Procedure: Analysis and integration of available data, 2007 to 2020. Results: Cumulative growth in the Canadian veterinary workforce was 38%, and 49% for companion animal veterinarians. Clients per companion animal veterinarian decreased 30% from 2008 to 2020. Absolute client numbers increased 1.3%, compared to pet population growth of 17%. Medicalized pets (those that had received veterinary care in the past year) increased 25%, from 9.02 million in 2007 to 11.24 million in 2020. Non-medicalized pets increased 1.8%, from 4.48 million to 4.56 million. In 2007, 33% of pets were non-medicalized, compared to 29% (15% of dogs and 42% of cats) in 2020. There was a cumulative increase of 31% for total non-medicalized dogs, and a change of -5.6% for cats. Gross and net revenues per client increased by 99 and 112%, respectively, compared to cumulative inflation of 21%. Conclusion and clinical relevance: The analysis identified a large cohort of pets that had not received veterinary care each year. The trends were fewer clients per veterinarian, each paying higher veterinary costs, and suggested a relative, rather than absolute, veterinary capacity shortage overall. Accessible care-provision models must be encouraged, regulated for, and allowed to flourish alongside traditional models.

Tendances en matière d'accès des animaux de compagnie aux soins vétérinaires au Canada, 2007 à 2020. Objectif: Évaluer les tendances en matière d'accès aux soins vétérinaires pour les animaux de compagnie au Canada. Procédure: Analyse et intégration des données disponibles, 2007 à 2020. Résultats: La croissance cumulative de la main-d'œuvre vétérinaire canadienne était de 38 %, et de 49 % pour les médecins vétérinaires d'animaux de compagnie. Le nombre de clients par vétérinaire pour animaux de compagnie a diminué de 30 % entre 2008 et 2020. Le nombre absolu de clients a augmenté de 1,3 %, comparé à une croissance de la population d'animaux de compagnie de 17 %. Les animaux de compagnie médicalisés (ceux qui ont reçu des soins vétérinaires au cours de l'année écoulée) ont augmenté de 25 %, passant de 9,02 millions en 2007 à 11,24 millions en 2020. Les animaux de compagnie non médicalisés ont augmenté de 1,8 %, passant de 4,48 millions à 4,56 millions. En 2007, 33 % des animaux de compagnie étaient non médicalisés, contre 29 % (15 % des chiens et 42 % des chats) en 2020. Il y a eu une augmentation cumulée de 31 % pour le total des chiens non médicalisés, et une variation de ­5,6 % pour les chats. Les revenus bruts et nets par client ont augmenté respectivement de 99 et 112 %, par rapport à une inflation cumulée de 21 %. Conclusion et pertinence clinique: L'analyse a identifié chaque année une large cohorte d'animaux de compagnie qui n'avaient pas reçu de soins vétérinaires. Les tendances étaient moins de clients par vétérinaire, chacun payant des frais vétérinaires plus élevés, et suggéraient une pénurie globale de capacité vétérinaire relative plutôt qu'absolue. Les modèles de prestation de soins accessibles doivent être encouragés, réglementés et autorisés à prospérer aux côtés des modèles traditionnels.(Traduit par Dr Serge Messier).

Perspective: Hidden biases in isotope delta results and the need for comprehensive reporting.

Measurements of stable-isotope composition on an isotope-delta scale can be subject to bias between laboratories or over time within a single laboratory. This bias can arise not just from differences in method protocol but also from changes in reporting guidelines, or even to the isotope-delta scales themselves. Without a clear description of method protocols, including all sample preparation steps, instrumental parameters and settings, data processing including calibration of results and estimation of measurement uncertainty, the traceability and comparability of isotope-delta values cannot be assured as bias(es) may remain hidden. To address this need, there are now clear guidelines published by IUPAC for reporting isotope-delta values for the "light" elements hydrogen, carbon, nitrogen, oxygen and sulfur.1 We recommend that authors and reviewers adhere to those guidelines when preparing and reviewing future publications.

Guidance for characterization of in-house reference materials for light element stable isotope analysis.

RATIONALE: Preparation of in-house reference materials (RMs) is an important aspect of light element stable isotope analysis. While some relevant information is available, there is as yet no clear set of guidelines available covering all aspects of in-house production and characterization of RMs. METHODS: To address this need, the experience of production of certified reference materials under accreditation to ISO 17034:2016 and ISO/IEC 17025:2017 has been distilled into guidance for production of in-house RMs that are fit-for-purpose. RESULTS: The guidance provided covers five areas: (i) planning; (ii) material considerations including preparation, packaging, and storage; (iii) measurements and assessments; (iv) value and uncertainty assignment; and (v) monitoring and use. CONCLUSIONS: In-house RMs prepared by following this guidance can be used to provide traceability to measurement results when used for normalization or for quality control and/or assurance purposes.

Synergistic effects of harvest and climate drive synchronous somatic growth within key New Zealand fisheries.

Fisheries harvest has pervasive impacts on wild fish populations, including the truncation of size and age structures, altered population dynamics and density, and modified habitat and assemblage composition. Understanding the degree to which harvest-induced impacts increase the sensitivity of individuals, populations and ultimately species to environmental change is essential to ensuring sustainable fisheries management in a rapidly changing world. Here we generated multiple long-term (44-62 years), annually resolved, somatic growth chronologies of four commercially important fishes from New Zealand's coastal and shelf waters. We used these novel data to investigate how regional- and basin-scale environmental variability, in concert with fishing activity, affected individual somatic growth rates and the magnitude of spatial synchrony among stocks. Changes in somatic growth can affect individual fitness and a range of population and fishery metrics such as recruitment success, maturation schedules and stock biomass. Across all species, individual growth benefited from a fishing-induced release of density controls. For nearshore snapper and tarakihi, regional-scale wind and temperature also additively affected growth, indicating that future climate change-induced warming and potentially strengthened winds will initially promote the productivity of more poleward populations. Fishing increased the sensitivity of deep-water hoki and ling growth to the Interdecadal Pacific Oscillation (IPO). A forecast shift to a positive IPO phase, in concert with current harvest strategies, will likely promote individual hoki and ling growth. At the species level, historical fishing practices and IPO synergized to strengthen spatial synchrony in average growth between stocks separated by 400-600 nm of ocean. Increased spatial synchrony can, however, increase the vulnerability of stocks to deleterious stochastic events. Together, our individual- and species-level results show how fishing and environmental factors can conflate to initially promote individual growth but then possibly heighten the sensitivity of stocks to environmental change.

Food Matrix Reference Materials for Hydrogen, Carbon, Nitrogen, Oxygen, and Sulfur Stable Isotope-Ratio Measurements: Collagens, Flours, Honeys, and Vegetable Oils.

An international project developed, quality-tested, and measured isotope-delta values of 10 new food matrix reference materials (RMs) for hydrogen, carbon, nitrogen, oxygen, and sulfur stable isotope-ratio measurements to support food authenticity testing and food provenance verification. These new RMs, USGS82 to USGS91, will enable users to normalize measurements of samples to isotope-delta scales. The RMs include (i) two honeys from Canada and tropical Vietnam, (ii) two flours from C3 (rice) and C4 (millet) plants, (iii) four vegetable oils from C3 (olive, peanut) and C4 (corn) plants, and (iv) two collagen powders from marine fish and terrestrial mammal origins. An errors-in-variables regression model included the uncertainty associated with the measured and assigned values of the RMs, and it was applied centrally to normalize results and obtain consensus values and measurement uncertainties. Utilization of these new RMs should facilitate mutual compatibility of stable isotope data if accepted normalization procedures are applied and documented.

Absolute isotope ratios defining isotope scales used in isotope ratio mass spectrometers and optical isotope instruments.

RATIONALE: The isotope delta is calculated from the isotope ratio of a sample and the absolute isotope ratio of the zero reference point defining each stable isotope international scale (Rstd ). Therefore, Rstd requires accurate determination. However, the literature contains a large number of Rstd values, and selection of different Rstd may lead to inconsistency in reporting and recalculating stable isotope results. METHODS: We reviewed Rstd used in the proprietary software provided by the manufacturers of stable isotope instruments commonly employed for analyses of stable HCNOS compositions. We compared the Rstd values and assessed the potential implications of using different Rstd and the normalization versus tank working gas standard for consistency in reporting stable isotope results. RESULTS: Different Rstd values are used by different manufacturers of stable isotope analytical instruments. For R(2 H/1 H)VSMOW two different but very similar values are used, 0.00015575 and 0.00015576; for R(13 C/12 C)VPDB three different values are used, 0.0111802, 0.0112372 and 0.01118028; and for R(15 N/14 N)Air-N2 two values, 0.0036782 and 0.0036765, are used. All manufacturers are using the same value for R(18 O/16 O)VSMOW , 0.00200520, but three different values for R(18 O/16 O)VPDB , 0.002067200, 0.00208835 and 0.002088349. For R(34 S/32 S)VCDT four different Rstd are used, 0.0441509, 0.0441626, 0.044162589 and 0.0441520597. CONCLUSIONS: The use of different Rstd values may lead to differences in the isotope delta values obtained if the normalization versus working standard gas is applied. For the range of Rstd used in proprietary software, the potential differences are lowest for oxygen (< 0.002 ‰) and nitrogen (< 0.001 ‰), and highest for carbon (0.107 to 0.112 ‰) and sulfur (0.023 ‰). Evaluation of the existing Rstd values and recommendations for the best estimates are highly desirable to ensure worldwide consistency in stable isotope data reporting.

Recalculation of stable isotope expressions for HCNOS: EasyIsoCalculator.

RATIONALE: The stable HCNOS isotope compositions can be reported as (a) the isotope ratio of two stable isotopes (R); (b) the isotope delta value (δ); and (c) the atom fraction of the isotopes (x). Recalculations between these different expressions are needed frequently and require the use of the absolute isotope ratio for the zero points of the stable isotope delta scales (Rstd). The inconsistent use of Rstd values may lead to a discrepancy in recalculated results. METHODS: We summarised the recalculation procedures between different expressions of the stable isotope compositions and introduced a user-friendly EasyIsoCalculator that allows the recalculation between the main expressions of isotope compositions. We mathematically and empirically evaluated the possible inconsistencies in reporting of the stable isotope data due to the use of different Rstd and different normalisation methods. RESULTS: The recalculation between δ-values and other expressions of the stable isotope compositions always involves the use of Rstd. The choice of Rstd will have a significant influence on the recalculated values. The use of different Rstd values has a significant influence also on the normalisation of raw values but only when the normalisation is conducted versus the working standard gas value, causing discrepancy, e.g. for δ(13C/12C) up to ~ 0.3 ‰. CONCLUSIONS: Differences in the selection of Rstd value may lead to significant differences among different laboratories. The uncertainty in the calculations originates primarily from the uncertainty in the Rstd determination; however, it is lower than the discrepancy arising from the inconsistent use of Rstd. Consistent use of the same Rstd values is required to eliminate the unnecessary discrepancy if different data sets are recalculated from delta value to other expressions.

Systematic comparison of post-column isotope dilution using LC-CO-IRMS with qNMR for amino acid purity determination.

Determination of the purity of a substance traceable to the International System of Units (SI) is important for the production of reference materials affording traceability in quantitative measurements. Post-column isotope dilution using liquid chromatography-chemical oxidation-isotope ratio mass spectrometry (ID-LC-CO-IRMS) has previously been suggested as a means to determine the purity of organic compounds; however, the lack of an uncertainty budget has prevented assessment of the utility this approach until now. In this work, the previously published ID-LC-CO-IRMS methods have not only been improved by direct gravimetric determination of the mass flow of 13C-labelled spike but also a comprehensive uncertainty budget has been established. This enabled direct comparison of the well-characterised ID-LC-CO-IRMS method to quantitative nuclear magnetic resonance spectroscopy (qNMR) for purity determination using valine as the model compound. The ID-LC-CO-IRMS and qNMR methods provided results that were in agreement within the associated measurement uncertainty for the purity of a sample of valine of (97.1 ± 4.7)% and (99.64 ± 0.20)%, respectively (expanded uncertainties, k = 2). The magnitude of the measurement uncertainty for ID-LC-CO-IRMS determination of valine purity precludes the use of this method for determination of purity by direct analysis of the main component in the majority of situations; however, a mass balance approach is expected to result in significantly improved measurement uncertainty.

Practical and theoretical considerations for the determination of δ13 CVPDB values of methylmercury in the environment.

RATIONALE: Analytical methods that can identify the source and fate of mercury and organomercury compounds are likely to be useful tools to investigate mercury in the environment. Carbon isotope ratio analysis of methylmercury (MeHg) together with mercury isotope ratios may offer a robust tool to study environmental cycling of organomercury compounds within fish tissues and other matrices. METHODS: MeHg carbon isotope ratios were determined by gas chromatography/combustion-isotope ratio mass spectrometry (GC/C-IRMS) either directly or following derivatization using sodium tetraethylborate. The effects of a normalization protocol and of derivatization on the measurement uncertainty of the methylmercury δ13 CVPDB values were investigated. RESULTS: GC/C-IRMS analysis resulted in a δ13 CVPDB value for an in-house MeHg reference material of δ13 CVPDB = -68.3 ± 7.7‰ (combined standard uncertainty, k = 1). This agreed very well with the value obtained by offline flow-injection analysis/chemical oxidation/isotope ratio mass spectrometry of δ13 CVPDB = -68.85 ± 0.17‰ (combined standard uncertainty, k = 1) although the uncertainty was substantially larger. The minimum amount of MeHg required for analysis was determined to be 20 µg. CONCLUSIONS: While the δ13 CVPDB values of MeHg can be obtained by GC/C-IRMS methods with or without derivatization, the low abundance of MeHg precludes such analyses in fish tissues unless there is substantial MeHg contamination. Environmental samples with sufficient MeHg pollution can be studied using these methods provided that the MeHg can be quantitatively extracted. The more general findings from this study regarding derivatization protocol implementation within an autosampler vial as well as measurement uncertainty associated with derivatization, normalization to reporting scales and integration are applicable to other GC/C-IRMS-based measurements.

Lessons learned from inter-laboratory studies of carbon isotope analysis of honey.

Forensic application of carbon isotope ratio measurements of honey and honey protein to investigate the degree of adulteration with high fructose corn syrup or other C4 plant sugars is well established. These measurements must use methods that exhibit suitable performance criteria, particularly with regard to measurement uncertainty and traceability - low levels of adulteration can only be detected by methods that result in suitably small measurement uncertainties such that differences of 1‰ or less can be reliably detected. Inter-laboratory exercises are invaluable to assess the state-of-the art of measurement capabilities of laboratories necessary to achieve such performance criteria. National and designated metrology institutes from a number of countries recently participated in an inter-laboratory assessment (CCQM-K140) of stable carbon isotope ratio determination of bulk honey. The same sample material was distributed to a number of forensic isotope analysis laboratories that could not participate directly in the metrological comparison. The results from these studies have demonstrated that the majority of participants provided isotope delta values with acceptable performance metrics; that all participants ensured traceability of their results; and that where measurement uncertainties were reported; these were fit-for-purpose. A number of the forensic laboratories only reported precision rather than full estimates of measurement uncertainty and this was the major cause of the few instances of questionable performance metrics. Reporting of standard deviations in place of measurement uncertainties is common practice outside metrology institutes and the implications for interpretations of small differences in isotopic compositions are discussed. The results have also highlighted a number of considerations that are useful for organisers of similar inter-laboratory studies in the future.

Looking back to move forward: a twenty-year audit of herpes zoster in Asia-Pacific.

BACKGROUND: Herpes zoster (HZ) is a prevalent viral disease that inflicts substantial morbidity and associated healthcare and socioeconomic burdens. Current treatments are not fully effective, especially among the most vulnerable patients. Although widely recommended, vaccination against HZ is not routine; barriers in Asia-Pacific include long-standing neglect of adult immunisation and sparse local data. To address knowledge gaps, raise awareness, and disseminate best practice, we reviewed recent data and guidelines on HZ from the Asia-Pacific region. METHODS: We searched PubMed, Scopus, and World Health Organization databases for articles about HZ published from 1994 to 2014 by authors from Australia, China, Hong Kong, India, Indonesia, Japan, Korea, Malaysia, New Zealand, the Philippines, Singapore, Taiwan, Thailand, and Vietnam. We selected articles about epidemiology, burden, complications, comorbidities, management, prevention, and recommendations/guidelines. Internet searches retrieved additional HZ immunisation guidelines. RESULTS: From 4007 retrieved articles, we screened-out 1501 duplicates and excluded 1264 extraneous articles, leaving 1242 unique articles. We found guidelines on adult immunisation from Australia, India, Indonesia, Malaysia, New Zealand, the Philippines, South Korea, and Thailand. HZ epidemiology in Asia-Pacific is similar to elsewhere; incidence rises with age and peaks at around 70 years - lifetime risk is approximately one-third. Average incidence of 3-10/1000 person-years is rising at around 5% per year. The principal risk factors are immunosenescence and immunosuppression. HZ almost always causes pain, and post-herpetic neuralgia is its most common complication. Half or more of hospitalised HZ patients have post-herpetic neuralgia, secondary infections, or inflammatory sequelae that are occasionally fatal. These disease burdens severely diminish patients' quality of life and incur heavy healthcare utilisation. CONCLUSIONS: Several countries have abundant data on HZ, but others, especially in South-East Asia, very few. However, Asia-Pacific countries generally lack data on HZ vaccine safety, efficacy and cost-effectiveness. Physicians treating HZ and its complications in Asia-Pacific face familiar challenges but, with a vast aged population, Asia bears a unique and growing burden of disease. Given the strong rationale for prevention, most adult immunisation guidelines include HZ vaccine, yet it remains underused. We urge all stakeholders to give higher priority to adult immunisation in general and HZ in particular.

Evaluation of Two New Indices of Blood Pressure Variability Using Postural Change in Older Fallers.

To evaluate the utility of blood pressure variability (BPV) calculated using previously published and newly introduced indices using the variables falls and age as comparators.While postural hypotension has long been considered a risk factor for falls, there is currently no documented evidence on the relationship between BPV and falls.A case-controlled study involving 25 fallers and 25 nonfallers was conducted. Systolic (SBPV) and diastolic blood pressure variability (DBPV) were assessed using 5 indices: standard deviation (SD), standard deviation of most stable continuous 120 beats (staSD), average real variability (ARV), root mean square of real variability (RMSRV), and standard deviation of real variability (SDRV). Continuous beat-to-beat blood pressure was recorded during 10 minutes' supine rest and 3 minutes' standing.Standing SBPV was significantly higher than supine SBPV using 4 indices in both groups. The standing-to-supine-BPV ratio (SSR) was then computed for each subject (staSD, ARV, RMSRV, and SDRV). Standing-to-supine ratio for SBPV was significantly higher among fallers compared to nonfallers using RMSRV and SDRV (P = 0.034 and P = 0.025). Using linear discriminant analysis (LDA), 3 indices (ARV, RMSRV, and SDRV) of SSR SBPV provided accuracies of 61.6%, 61.2%, and 60.0% for the prediction of falls which is comparable with timed-up and go (TUG), 64.4%.This study suggests that SSR SBPV using RMSRV and SDRV is a potential predictor for falls among older patients, and deserves further evaluation in larger prospective studies.

Postural blood pressure electrocardiographic changes are associated with falls in older people.

OBJECTIVES: To determine the magnitude of postural blood pressure change, differences in ECG between fallers and non-fallers were measured. Postural blood pressure change is associated with symptoms of dizziness, presyncope, and syncope. METHODS: In this cross-sectional study were included participants from The Malaysian Falls Assessment and Intervention Trial: fallers, aged 65 years or older with two or more falls or one injurious fall in 12 months, from a teaching hospital; and non-fallers, aged 65 years and older found through word-of-mouth and advertising. Noninvasive beat-to-beat blood pressure was measured at 10 min supine rest and 3 min standing. The maximal drop in systolic and diastolic pressure was calculated from a 12-lead ECG interpreted by a cardiologist. Basic demographics, medical history, and symptoms of dizziness, presyncope, and syncope were recorded for all patients. RESULTS: We recruited 155 fallers and 112 non-fallers. Fallers had a significantly longer PR interval (179 ± 32 vs. 168 ± 27 ms, p = 0.013) and a longer corrected QT interval (449 ± 41 vs. 443 ± 39 msec, p = 0.008), and larger change in SBP (28 ± 14 vs. 19 ± 9 mmHg, p < 0.001) with posture change. SBP drop of ≥30mmHg associated with recurrent and injurious falls [odds ratio [95 % confidence interval] = 7.61 (3.18-18.21)]. The changes remained significant after adjustment for symptoms of dizziness, presyncope and syncope. INTERPRETATION: Older individuals with recurrent and injurious falls have significantly longer PR and QT intervals and larger SBP reduction with posture change as compared to non-fallers, and these are not explained by the presence of dizziness, presyncope, or syncope. SBP cut-off of ≥30mmHg considered for postural measurements using continuous BP monitors, the significance of this value needs to be evaluated.