Analysis of antimicrobial sales data of the main distributor in Quebec from 2016 to 2019: An estimate of usage in dairy cattle,horses, and small animals

Because antimicrobial usage (AMU) data are crucial in understanding and dealing with the threat that antimicrobial resistance (AMR) poses to global health, data of the sale of antimicrobials from 2016 to 2019 of CDMV Inc. — a major distributor of veterinary products in Canada — were collected and analyzed for the province of Quebec. The primary objective was to describe the evolution of AMU sales data for dairy cattle, small animals, and horses; a secondary objective was to determine effects of a new provincial regulation on antimicrobials of very high importance (in Quebec) on sales for dairy cattle. Results are described in milligrams of antimicrobials per kilogram of animal biomass (mg/PCU) for dairy cattle, small animals, and horses; intramammary products were analyzed for number of treatments per 100 cow-years; and results for dairy cattle were compared in Canadian-defined course doses for cattle (DCDbovCA) per 100 cow-years to a recent study for this species in Quebec. Between 2016 and 2019, there were decreased sales of Category 1 antimicrobials for all species included in the study (Category 1-VI for small animals). This reduction was even more apparent for dairy cattle, for which a 76% decrease occurred from 2018 to 2019 (1.7 to 0.4 mg/PCU). This marked reduction was attributed to the new regulation implemented in February 2019. Since a farm- and clinic-level AMU monitoring system has not yet been implemented in Quebec, analysis of CDMV Inc. sales enabled observations of temporal trends in AMU for dairy cattle, horses, and small animals. These temporal trends based on CDMV Inc. sales will be useful for making comparisons and validating trends derived from farm- and clinic-level data generated by a monitoring system.     

Lyme disease prevention: A content analysis of Canadian patient group and government websites

The quality of information presented on health‐related websites—in terms of comprehensiveness, accuracy and consistency—is a public health concern. To date, the consistency of information across Canadian websites devoted to Lyme disease (LD) prevention has not been evaluated. The first aim of this study was to describe the contents and recommendations of LD prevention websites provided by two types of Canadian organizations: government (n = 3) and patient groups (n = 3). A second objective was to analyse the level of convergence among these websites in terms of their prevention‐related content. Initial coding of the content resulted in information segments grouped into 114 subthemes related to nine overarching themes: tick habitat suitability, risk period, transmission, personal protection, peridomestic environmental management, tick identification and removal, early symptoms, testing and diagnosis and preventive treatment. Comparative content analyses were performed both within and between the content of websites of the two organization types. The themes most frequently addressed by both organization types were personal protection (20% of the prevention‐related content in patient group websites and 22% of the prevention‐related content in government websites), transmission (12% and 16%, respectively) and tick identification and removal (19% and 15%, respectively). Government websites’ information was generally convergent with that of patient group websites (four highly convergent themes, three moderately convergent and two divergent). Nevertheless, of particular concern were divergent messages and inaccurate information found on 11 subthemes out of 103. Examples included other possible modes of transmission and the ineffectiveness of DEET insect repellent. These results suggest the need for public health and health communications research on the issue of the quality of LD prevention information found on the Internet.     

Air-liquid partition coefficients of aroma volatiles in frozen sugar solutions

Static headspace gas chromatography was used to measure air-solution partition coefficients of homologous series of methyl ketones and ethyl esters in aqueous sugar solutions. The measurements were performed in a temperature range from 25 to -25 degrees C. A rather unexpected temperature dependence of the partition coefficients was observed at subzero temperatures; that is, partition coefficients were found to increase in the temperature interval from 0 to -10 degrees C. A simple model, based on the freeze concentration effect, is proposed to explain the observed temperature dependence.     

Mineralogical control of organic carbon dynamics in a volcanic ash soil on La Réunion

In soil carbon dynamics, the role of physicochemical interactions between organic matter and minerals is not well understood nor quantified. This paper examines the interactions between soil organic matter and poorly crystalline aluminosilicates in a volcanic ash soil on La Réunion in the southern tropics. The soil examined is a profile composed of a surface soil (L-Ao-E-Bh) overlying four buried horizons (horizons 2Bw, 3Bw, 4Bw, 5Bw) that have all developed from successive tephra deposits. Non-destructive spectroscopy (XRD, FTIR and NMR of Si and Al) showed that the mineralogical composition varies from one buried horizon to another. Further, we show that buried horizons characterized by large amounts of crystalline minerals (feldspars, gibbsite) have the least capacity to store organic matter and the fastest carbon turnover. In contrast, buried horizons containing much poorly crystalline material (proto-imogolite and proto-imogolite allophane, denoted LP-ITM) store large amounts of organic matter which turns over very slowly. To understand the mechanism of interactions between LP-ITM and organic matter better, we focused on a horizon formed exclusively of LP-ITM. We demonstrate, using Δ¹⁴C and δ¹³C values, that even though LP-ITM is extraordinarily effective at stabilizing organic matter, C linked to LP-ITM is still in dynamic equilibrium with its environment and cycles slowly. Based on Δ¹⁴C values, we estimated the residence time of organic C as ∼ 163 000 years for the most stabilized subhorizon, a value that is comparable to that for organic carbon stabilized in Hawaiian volcanic soils. However, this calculation is likely to be biased by the presence of microcharcoal. We characterized the organo-mineral binding between organic matter and LP-ITM by ²⁷Al NMR, and found that the organic matter is not only chelated to LP-ITM, but it may also limit the polymerization of mineral phases to a stage between proto-imogolite and proto-imogolite allophane. Our results demonstrate the important role of poorly crystalline minerals in the storage of organic C, and show that mineral and organic compounds have to be studied simultaneously to understand the dynamics of organic C in the soil.     

In-field development of a conceptual crop functioning and management model: A case study on cotton in southern Mali

West African cotton production has increased rapidly in recent years. Cotton is being cropped under new ecological conditions by new cotton-producing farmers, but the cropping techniques recommended by developers have essentially remained the same. Methodologies are needed to generate a broad scope of recommendations on cropping techniques to deal with the increasing diversity concerning farmers and cropping conditions.

A conceptual model of a cotton field was developed that approaches a crop field as a biophysical system under the influence of a “technical system” (i.e. the combination of farmers’ practices implemented in the field). The system outputs were restricted to yield and the main yield components. A theoretical model was first designed on the basis of published data and expert knowledge on cotton physiology, local soil–climate conditions and farmers’ practices. It was based on five specific hypotheses on links between technical and biophysical systems. The hypotheses were tested in a local farmers’ network. Thirty “cropping situations” (soil–crop–technique combinations) were selected in farmers’ fields around Katogo village (Mali), a village that had been previously selected for a cotton crop management prototyping program. Homogeneous groups of situations were drawn up on the basis of the dynamics of crop aerial biomass accumulation. They were compared for their management and environment features. The initial conceptual model was then simplified, while taking the measured variability in its components and the sensitivity of the outputs to these components into account. This conceptual model is being evaluated in other villages, where we have partnerships with farmers, in order to develop a version adapted to a broad range of situations.     

Grazing by nematodes on rhizosphere bacteria enhances nitrate and phosphorus availability to Pinus pinaster seedlings

The microbial loop is thought to play a major role in the mineralization of nutrients such as nitrogen (N) and phosphorus (P) in terrestrial ecosystems. This microbial loop is based on the grazing of bacteria by predators such as bacterial-feeding nematodes. However, little is known about the impact of grazing by nematodes on the mineral nutrition of woody plants. This study was undertaken to quantify the effect of nematode grazing on bacteria in the rhizosphere on the root architecture, growth and mineral nutrition (N and P) of a woody species (Pinus pinaster). Young P. pinaster seedlings were cultivated for 35 days in a simplified sterile experimental system with bacteria (Bacillus subtilis) and bacterivorous nematodes (Rhabditis sp.) isolated from soil samples collected from a 15-year old stand of maritime pine. To check the hypothesis that bacteria could be a source of nutrients, especially N, two N sources were supplied in the medium: (i) bacterial N labeled with ¹⁵N and (ii) nitrate. Phosphorus was supplied as insoluble inorganic tri-calcium phosphate (TCP). The results showed that the ¹⁵N flow from the bacteria to the plant shoots was only significant when nematodes were present, with an average accumulation of 14 ± 5 μg plant⁻¹ of ¹⁵N. Plants cultivated with nematodes also accumulated significantly more total N in their shoots than sterile ones or inoculated with bacteria, resulting in a net average increase in N of 700 μg plant⁻¹. The same result was observed for the total P accumulation in the shoots, as plants with nematodes accumulated an average of 300 μg plant⁻¹ more P than sterile ones or inoculated with bacteria. However, the presence of bacteria, whether alone or with nematodes, did not modify the root architecture. These results demonstrated that the presence of bacterial-feeding nematodes significantly enhanced N and P availability to P. pinaster seedlings, probably by improving plant use of nitrate and insoluble P supplied in the medium.     

Specific features and survival of French bulldogs with congenital pulmonic stenosis: a prospective cohort study of 66 cases

Introduction

The objectives of this study were to characterize the epidemiological, clinical, and echocardiographic features of French bulldogs (FBs) with congenital pulmonic stenosis and document their survival times and risk factors for cardiac death (CD).