Faculty of Agricultural and Food Sciences Scholarly Works

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    Open Access
    The Food and Nutrition Security for Manitoba Youth (FANS) study: rationale, methods, dietary intakes and body mass index
    (2022-10-20) Slater, Joyce; Pilli, Bhanu; Hinds, Aynslie; Katz, Alan; Urquia, Marcelo L.; Sanguins, Julianne; Green, Chris; Cidro, Jaime; Chateau, Dan; Nickel, Nathan
    Abstract Background Good nutrition and access to healthy foods are essential for child growth and development. However, there are concerns that Canadian children do not have a healthy diet, which may be related to dietary choices as well as lack of access to healthy foods. The FANS (Food and Nutrition Security for Children and Youth) study examined the nutrition and food security status of youth in the province of Manitoba, Canada. This paper describes methods, dietary intakes, and body mass index for the FANS study.  Methods This cross-sectional study included 1587 Manitoba grade nine students who completed a self-administered web-based survey. Data was collected on demographic characteristics, dietary intake (24-h recall), food behaviors, food security, and self-report health indicators. Dietary data was compared to national dietary guidelines (Dietary Reference Intakes and Canada’s Food Guide). Mean and median nutrient and food group intakes were calculated with corresponding measures of variability. Chi-square tests compared percentage of respondents not meeting key nutrients and food groups. Significant differences in percentage of total servings for each food group were determined by a Kruskal–Wallis test, and differences between different caloric groups were assessed using Dunn’s test for post-hoc comparisons.  Results Half of study respondents were female (50.5%). Median energy intake was higher in males (2281 kcal) compared with females (1662 kcal), with macronutrient distribution of 52%, 16%, and 32% for carbohydrates, protein, and fats respectively. Most participants consumed inadequate fibre (94%), vitamin D (90%), and calcium (73%), while median sodium intakes exceeded recommendations for males but not females. A majority of participants did not meet Health Canada’s recommendations for food group servings: Vegetables and Fruit (93%), Milk and Alternatives (74%), Meat and Alternatives (57%) and Grain Products (43%). Other Foods, including sugar sweetened beverages and juice, were consumed by most participants. Higher energy consumers had a greater proportion of food servings coming from Other Foods. 72.1% of students were classified as having a healthy weight and 25% were classified as overweight or obese. Conclusion Poor dietary intakes and body mass index values indicate an urgent need for policy and program strategies to support healthy eating habits and food awareness in Manitoba youth.
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    Open Access
    Combining deep sequencing and conventional molecular approaches reveals broad diversity and distribution of fleas and Bartonella in rodents and shrews from Arctic and Subarctic ecosystems
    (2022-10-13) Buhler, Kayla J.; Fernando, Champika; Hill, Janet E.; Galloway, Terry; Carriere, Suzanne; Fenton, Heather; Fauteux, Dominique; Jenkins, Emily J.
    Abstract Background Bartonella are intracellular bacteria that are transmitted via animal scratches, bites and hematophagous arthropods. Rodents and their associated fleas play a key role in the maintenance of Bartonella worldwide, with > 22 species identified in rodent hosts. No studies have addressed the occurrence and diversity of Bartonella species and vectors for small mammals in Arctic and Subarctic ecosystems, which are increasingly impacted by invasive species and climate change. Methods In this study, we characterized the diversity of rodent fleas using conventional PCR targeting the mitochondrial cytochrome c oxidase II gene (COII) and Bartonella species in rodents and shrews (n = 505) from northern Canada using conventional PCR targeting the ITS (intergenic transcribed spacer) region and gltA (citrate synthase) gene. Metagenomic sequencing of a portion of the gltA gene was completed on a subset of 42 rodents and four rodent flea pools. Results Year, total summer precipitation the year prior to sampling, average minimum spring temperature and small mammal species were significant factors in predicting Bartonella positivity. Occurrence based on the ITS region was more than double that of the gltA gene and was 34% (n = 349) in northern red-backed voles, 35% (n = 20) in meadow voles, 37% (n = 68) in deer mice and 31% (n = 59) in shrews. Six species of Bartonella were identified with the ITS region, including B. grahamii, B. elizabethae, B. washoensis, Candidatus B. rudakovii, B. doshiae, B. vinsonii subsp. berkhoffii and subsp. arupensis. In addition, 47% (n = 49/105) of ITS amplicons had < 97% identity to sequences in GenBank, possibly due to a limited reference library or previously unreported species. An additional Bartonella species (B. heixiaziensis) was detected during metagenomic sequencing of the gltA gene in 6/11 rodents that had ITS sequences with < 97% identity in GenBank, highlighting that a limited reference library for the ITS marker likely accounted for low sequence similarity in our specimens. In addition, one flea pool from a northern red-backed vole contained multiple species (B. grahamii and B. heixiaziensis). Conclusion Our study calls attention to the usefulness of a combined approach to determine the occurrence and diversity of Bartonella communities in hosts and vectors. Graphical Abstract
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    Open Access
    The pangenome of the wheat pathogen Pyrenophora tritici-repentis reveals novel transposons associated with necrotrophic effectors ToxA and ToxB
    (2022-10-24) Gourlie, Ryan; McDonald, Megan; Hafez, Mohamed; Ortega-Polo, Rodrigo; Low, Kristin E.; Abbott, D. W.; Strelkov, Stephen E.; Daayf, Fouad; Aboukhaddour, Reem
    Abstract Background In fungal plant pathogens, genome rearrangements followed by selection pressure for adaptive traits have facilitated the co-evolutionary arms race between hosts and their pathogens. Pyrenophora tritici-repentis (Ptr) has emerged recently as a foliar pathogen of wheat worldwide and its populations consist of isolates that vary in their ability to produce combinations of different necrotrophic effectors. These effectors play vital roles in disease development. Here, we sequenced the genomes of a global collection (40 isolates) of Ptr to gain insights into its gene content and genome rearrangements. Results A comparative genome analysis revealed an open pangenome, with an abundance of accessory genes (~ 57%) reflecting Ptr’s adaptability. A clear distinction between pathogenic and non-pathogenic genomes was observed in size, gene content, and phylogenetic relatedness. Chromosomal rearrangements and structural organization, specifically around effector coding genes, were detailed using long-read assemblies (PacBio RS II) generated in this work in addition to previously assembled genomes. We also discovered the involvement of large mobile elements associated with Ptr’s effectors: ToxA, the gene encoding for the necrosis effector, was found as a single copy within a 143-kb ‘Starship’ transposon (dubbed ‘Horizon’) with a clearly defined target site and target site duplications. ‘Horizon’ was located on different chromosomes in different isolates, indicating mobility, and the previously described ToxhAT transposon (responsible for horizontal transfer of ToxA) was nested within this newly identified Starship. Additionally, ToxB, the gene encoding the chlorosis effector, was clustered as three copies on a 294-kb element, which is likely a different putative ‘Starship’ (dubbed ‘Icarus’) in a ToxB-producing isolate. ToxB and its putative transposon were missing from the ToxB non-coding reference isolate, but the homolog toxb and ‘Icarus’ were both present in a different non-coding isolate. This suggests that ToxB may have been mobile at some point during the evolution of the Ptr genome which is contradictory to the current assumption of ToxB vertical inheritance. Finally, the genome architecture of Ptr was defined as ‘one-compartment’ based on calculated gene distances and evolutionary rates. Conclusions These findings together reflect on the highly plastic nature of the Ptr genome which has likely helped to drive its worldwide adaptation and has illuminated the involvement of giant transposons in facilitating the evolution of virulence in Ptr.
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    Open Access
    Policy responses to the COVID-19 pandemic in the Manitoba grocery sector: a qualitative analysis of media, organizational communications, and key informant interviews
    (2022-06-21) Riediger, Natalie D.; Slater, Joyce J.; Mann, Kelsey; Pilli, Bhanu; Derksen, Hannah; Perchotte, Chantal; Penner, Avery L.
    Abstract Objectives The COVID-19 pandemic has impacted all aspects of the food system, including the retail grocery sector. We sought to (objective 1) document and (objective 2) analyze the policies implemented in the grocery sector during the first wave of the pandemic in Manitoba, Canada. Methods Our qualitative policy analysis draws from organizational communications (websites and social media) (n = 79), news media articles (n = 95), and key informant interviews with individuals (n = 8) working within the grocery sector in urban and rural, Manitoba. Media and communications were extracted between March 9-May 8, 2020 and interviews were conducted in July–August, 2020. Results Newly implemented policies due to the pandemic fell under four inter-related themes: Employee health and wellbeing, Safety measures, Operational measures, and Community support. Employee health and wellbeing included sub-themes of financial and social support, health recommendations and protocols, and new employee guidelines. Safety measures encompassed numerous policies pertaining to sanitation, personal protection, transmission prevention, physical distancing, and limiting access. Overall, new policies were discussed as effective in making grocery shopping as safe as possible given the situation. Compliance and enforcement, employee teamwork, and support for employees were key themes related to perceptions of policy success in a challenging and inequitable context. Nevertheless, government support and communication was needed as well to ensure safety within the grocery sector. Conclusions The grocery sector reacted to the pandemic with the swift implementation of policies to address food supply issues, prevent transmission of the virus, support their employees as essential workers, and better serve high-risk populations.
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    Open Access
    Calcium-sensing Receptor is not Expressed in the Absorptive Enterocytes of Weaned Piglets
    (2022-03-16) Zhao, Xiaoya; Hui, Qianqu; Azevedo, Paula A; Nyachoti, Charles M.; O, Karmin; Yang, Chengbo
    The calcium-sensing receptor (CaSR) is a kokumi receptor that plays an essential role in nutrient sensing and animal physiology, growth, and development. Pig CaSR (pCaSR) was identified and characterized in the intestine. However, further research is still needed to confirm the expression of CaSR in the epithelial cells isolated from weaned piglets. In this study, primary enterocytes were isolated and characterized from the ileum of weaned piglets by the Weiser distended intestinal sac technique and fluorescence-activated cell sorting (FACS) based on sucrase-isomaltase as an enterocyte-specific marker. The expression of CaSR was investigated in both primary enterocytes and the intestinal porcine enterocyte cell line (IPEC-J2) by droplet digital PCR (ddPCR), immunofluorescence staining, and western blotting. Results demonstrated that porcine enterocytes could be obtained using FACS with the sucrase-isomaltase as the enterocyte-specific marker and that pCaSR is not expressed in both porcine ileal enterocytes and IPEC-J2 cells, which specifically identified the expression of pCaSR in ileal enterocytes with sensitive and specific approaches.