Ministry of Agriculture, Fisheries and Food

Background/Objectives: The bacterium Brochothrix campestris is closely related to Brochothrix thermosphacta, a known food spoilage agent, and Listeria monocytogenes, the causative agent of listeriosis. B. campestris garnered attention several years ago because it produces brochocin-C, a bacteriocin capable of inhibiting the growth of certain pathogens. It has been recently suggested that phages play a significant role in the evolution of B. thermosphacta, similar to the role they play for L. monocytogenes. However, understanding the role of phages in the evolution of B. campestris has been challenging because only a draft of genome sequences of a single B. campestris strain was previously available. Methods: In this study, DNA from the B. campestris type strain DSM 4712 was sequenced using Oxford Nanopore and Illumina technologies to obtain complete, high-quality genome sequences. Results: The assembly revealed the presence of a plasmid and a phage-plasmid. Additionally, chromosomal analysis identified several genomic islands, including one harboring the brochocin genes, suggesting that these genes may have undergone horizontal transfer. Conclusions: This study underscores the potential importance of phages in the evolution of B. campestris, and also highlights the need for further research into the interactions between Brochothrix species and their associated phages to better understand these complex biological relationships.

Particular attention has been paid to the nutritional potential of edible insects as well as the health benefits associated with their bioactive compounds. This paper focused on an in-depth review compiling the most recent information on health benefits of insect bioactive metabolites as well as their purification and identification, in addition to consumer attitudes towards edible insects. It was found that, insect bioactive metabolites, including marcocarpal, grandinol, trolline, pancratistatin, narciclasin, ungeremin, cantharidin, cordycepin, roseoflavin, lecithin, reblastatin, chitin, chitosan and desmosterol deemed to have biological activities, such as tumor suppression, anticancer, antihypertensive, anti-inflammatory, antioxidant, immunomodulator, neuroprotective, glycemic and lipid regulation, blood pressure reduction, regulation of intestinal bacterial flora and cardiovascular protection among others. Furthermore, proper sample preparation and extraction is the first step in the purification of bioactive metabolites from edible insects. After concentration, bioactive metabolites are purified using chromatographic and separation techniques including High-Performance Liquid Chromatography (HPLC), Gas Chromatography (GC), Thin-Layer Chromatography (TLC), Size-Exclusion Chromatography (SEC). Finally, their nutritional potential, health benefits, environmentally friendly, great taste, traditions, taboo, safety concerns, unpleasant past experiences, allergies, and unnaturalness are among the main factors influencing attitudes towards insect consumption.

Dairy cows commonly experience uterine bacterial infections post-calving, which can lead to reproductive tract inflamma­tion. While diagnosing uterine infection requires bacteriologi­cal culture, on-farm identification of inflammation is quicker. Moreover, antimicrobial treatment has shown positive impacts on reproductive performance of cows identified with inflam­mation of the reproductive tract. In the face of antimicrobial resistance concerns, however, the diagnostic of uterine infec­tion might become essential. In this prospective cross-sectional study, our aim was to assess the diagnostic validity of various tests for identifying uterine infection (UI) in dairy cows, and to evaluate their utility under different scenarios.

Abstract Outbreaks caused by migrant pests such as the armyworm, Mythimna unipuncta (Haworth, 1809) (Lepidoptera: Noctuidae), are generally unpredictable. In the province of Quebec, Canada, the arrival and dispersal of armyworms is monitored by capturing males using pheromone traps. Because only males are captured in pheromone-baited traps, trap catch is not predictive of subsequent larval occurrence and damage. We used traps baited with a feeding attractant to capture both male and female armyworm moths and evaluate their flight period at 11 sites across the province in 2018 and 2019. The reproductive status of females was also investigated by dissecting their reproductive apparatus to determine if they were sexually active when captured. The results showed two peak flight periods between May and August but high variation at the different sites and between years. Both sexes migrate in Quebec at the same time but in variable and unpredictable proportions. All spring migrant females had mated before capture, whereas some unmated females were captured later in the season. These results provide useful information to better monitor the armyworm in Quebec and to develop more appropriate integrated pest management strategies.

The genus Flavobacterium comprises a diversity of species, including fish pathogens. Multiple techniques have been used to identify isolates of this genus, such as phenotyping, polymerase chain reaction genotyping, and in silico whole-genome taxonomy. In this study, we demonstrate that whole-genome-based taxonomy, using average nucleotide identity and molecular phylogeny, is the most accurate approach for Flavobacterium species. We obtained various isolated strains from official collections; these strains had been previously characterized by a third party using various identification methodologies. We analyzed isolates by PCR genotyping using previously published primers targeting gyrB and gyrA genes, which are supposedly specific to the genus Flavobacterium and Flavobacterium psychrophilum, respectively. After genomic analysis, nearly half of the isolates had their identities re-evaluated: around a quarter of them were re-assigned to other genera and two isolates are new species of flavobacteria. In retrospect, the phenotyping method was the least accurate. While gyrB genotyping was accurate with the isolates included in this study, bioinformatics analysis suggests that only 70% of the Flavobacterium species could be appropriately identified using this approach. We propose that whole-genome taxonomy should be used for accurate Flavobacterium identification, and we encourage bacterial collections to review the identification of isolates identified by phenotyping.

The taxonomic assignment of sequences obtained by high throughput amplicon sequencing poses a limitation for various applications in the biomedical, environmental, and agricultural fields. Identifications are constrained by the length of the obtained sequences and the computational processes employed to efficiently assign taxonomy. Arriving at a consensus is often preferable to uncertain identification for ecological purposes. To address this issue, a new tool called “ASVmaker” has been developed to facilitate the creation of custom databases, thereby enhancing the precision of specific identifications. ASVmaker is specifically designed to generate reference databases for allocating amplicon sequencing data. It uses publicly available reference data and generates specific sequences derived from the primers used to create amplicon sequencing libraries. This versatile tool can complete taxonomic assignments performed with pre-trained classifiers from the SILVA and UNITE databases. Moreover, it enables the generation of comprehensive reference databases for specific genes in cases where no directly applicable database exists for taxonomic classification tools.

Mycobacterium avium subsp. paratuberculosis (MAP) is the causal agent of paratuberculosis, a chronic, contagious, and incurable enteric disease of ruminants. An in-house IS900 PCR assay validated for MAP detection in sheep has been shown to have a higher sensitivity than a commercial PCR and fecal culture. We have now compared the performance of this in-house IS900 PCR assay with a commercial ISMap02 PCR assay for the detection of MAP DNA in bovine dairy farm environmental samples. We purposefully selected 30 culture-positive, 62 culture-negative, and 62 non-interpretable environmental samples. We applied the IS900 PCR assay directly to the frozen inoculum of these samples. Inocula were incubated in an automated system, and growth was confirmed by an acid-fast bacilli stain and the IS900 PCR assay. Among culture-positive samples before incubation, the IS900 PCR assay yielded significantly more positive results than the ISMap02 PCR assay; however, among culture-negative samples, the IS900 PCR assay yielded positive results both before and after incubation. The ISMap02 PCR assay did not flag positively among the culture-negative samples either before or after incubation. The IS900 PCR assay is a sensitive method that can be used to detect MAP DNA in environmental samples before incubation. The ISMap02 PCR assay is a specific method used to detect MAP DNA in environmental samples both before and after incubation.

The bacterium Staphylococcus hyicus causes porcine exudative epidermitis in piglets, which represents both health and welfare concerns. Few genome sequences of this pathogen are published. We provide four additional ones to help future genomic analysis of S. hyicus. These are genomes of strains isolated from Canadian swine.