Machine learning models provide modest accuracy in predicting clinical impact of porcine reproductive and respiratory syndrome type 2 in Canadian sow herds.

Objective: To determine the predictive potential of the open reading frame 5 nucleotide sequence of porcine reproductive and respiratory syndrome (PRRS) virus and the basic demographic data on the severity of the impact on selected production parameters during clinical PRRS outbreaks in Ontario sow herds.

Methods: A retrospective longitudinal study of clinical outbreaks in Ontario sow herds at various points between September 5, 2009, and February 5, 2019, was conducted using herds as units of analysis. Data were gathered from study sow farms in Ontario at the start of each clinical outbreak.

Avian reovirus infection in turkeys with neurological disease in Alberta.

Avian reoviruses (ARVs) are ubiquitous and play a role in diseases affecting various organs in chickens and turkeys. In recent years, tenosynovitis and lameness emerged as the most frequently reported clinical conditions. In this report, we describe a case of neurological disease associated with ARV infection in 4-week-old turkeys in Alberta.

Transmission dynamics of highly pathogenic avian influenza virus at the wildlife-poultry-environmental interface: A case study.

Avian influenza viruses (AIVs) regularly circulate between wild and domestic bird populations. Following several high-profile outbreaks, highly pathogenic AIVs (HPAIV) with zoonotic potential have been the subject of increasing attention. While we know that HPAIV is transmitted between domestic birds, wildlife, and the environment, little is known about persistence and spillover/back at these interfaces.

Genotyping of infectious bronchitis virus in Canada.

From 2014-2023, infectious bronchitis virus (IBV) was detected in 6,589 samples from Canada, and partial nucleotide (nt) sequences of the IBV spike protein () gene were determined for 1,678 samples. Based on their gene nt sequence identities and origin, Canadian IBVs could be classified into 4 groups: 1) 50.3% were variant viruses related to strains described in the United States; 2) 45.

Canine distemper virus infection of vaccinal origin in a 14-week-old puppy.

The body of a 14-wk-old puppy () was submitted to the Animal Health Laboratory, University of Guelph, Ontario for postmortem examination following a history of intermittent anorexia and lethargy progressing to pyrexia, pruritic skin rash, mucoid nasal discharge, decreased mentation, dysphagia, muscle twitches, and focal seizures. Gross examination revealed rhinitis and pulmonary edema. Histologically, there was fibrinonecrotizing bronchopneumonia, tracheitis, and neutrophilic and lymphohistiocytic rhinitis; rarely within the cortical gray and white matter of the brain were small clusters of glial cells, with rare individual neutrophils in the choroid plexus.

Development of a multivalent adjuvanted inactivated vaccine against variant arthrotropic avian reoviruses.

Variant avian reoviruses (ARVs) are economically important emerging pathogens of poultry, which mainly affect young broiler chickens and cause significant production losses. Currently, there are no effective commercial vaccines available for control and prevention of emerging variant ARVs. In this study, monovalent inactivated adjuvated (20% Emulsigen D) broiler breeder vaccines containing antigens from ARV genotype cluster (C) group -2, -4, -5, or -6, and a multivalent vaccine containing antigens from all the four indicated genotypic cluster groups were developed and evaluated for their efficacy in protecting broiler progenies against homologous or heterologous ARV challenge.

Development of interactive dashboards for monitoring endemic animal pathogens in Ontario, Canada: Ontario interactive animal pathogen dashboards.

The advancement of web-based technologies makes it possible to build user interfaces or web pages that present and summarize complex data in easy-to-read graphical formats that emphasize key information. Taking advantage of this technologic progress, we addressed the need for real-time visualizations of trends for major pathogens in the largest livestock industries in Ontario: poultry, swine, and cattle. These visualizations were built using test data from the laboratory information management system of the Animal Health Laboratory at the University of Guelph, a large veterinary diagnostic laboratory in Ontario.

CANINE DISTEMPER VIRUS ECOLOGY: INSIGHTS FROM A LONGITUDINAL SEROLOGIC STUDY IN WILD RACCOONS (PROCYON LOTOR).

Increasing reports of canine distemper virus (CDV) in a variety of hosts, and changing CDV dynamics, have led to renewed interest in the ecology of CDV infections in wildlife. Longitudinal serologic studies provide insights into intrapopulation and intraindividual pathogen dynamics, but few studies in wildlife have been conducted. We used data from 235 raccoons (Procyon lotor) captured on more than one occasion between May 2011 and November 2013 to investigate CDV dynamics in Ontario, Canada.

Bronchopneumonia with interstitial pneumonia in beef feedlot cattle: Characterization and laboratory investigation.

Bronchopneumonia with interstitial pneumonia (BIP) has been considered a variant of acute interstitial pneumonia (AIP) rather than a distinct disease. This study compared 18 BIP, 24 bronchopneumonia (BP), and 13 AIP cases in feedlot beef cattle. Grossly, BIP cases typically had cranioventral lung lesions of similar morphology and extent as BP cases, but the caudodorsal lung appeared overinflated, bulged on section, and had interlobular edema and emphysema.

Assessment of seasonality of rotavirus PCR detection in swine from Ontario and Quebec between 2016-2020 using submissions to a diagnostic laboratory.

The goal of this study was to determine if seasonality of rotavirus A, B, and C infection is present in Ontario and Quebec swine herds by investigating submissions to a diagnostic laboratory. Samples (N = 1557) within 755 case submissions from Canadian swine herds between 2016 and 2020 were tested for rotaviruses A, B, and C using a real-time polymerase-chain reaction assay and described. Data from Ontario and Quebec were additionally analyzed using boxplots, 6-week rolling averages, time-series decomposition, and negative binomial regression models.

Genotyping and In Silico Analysis of Delmarva (DMV/1639) Infectious Bronchitis Virus (IBV) Spike 1 (S1) Glycoprotein.

Genetic diversity and evolution of infectious bronchitis virus (IBV) are mainly impacted by mutations in the spike 1 (S1) gene. This study focused on whole genome sequencing of an IBV isolate (IBV/Ck/Can/2558004), which represents strains highly prevalent in Canadian commercial poultry, especially concerning features related to its S1 gene and protein sequences. Based on the phylogeny of the S1 gene, IBV/Ck/Can/2558004 belongs to the GI-17 lineage.

Evaluation of five circulating strains of variant infectious bursal disease virus (varIBDV) for their immunogenicity as broiler breeder vaccines and protective efficacy in neonatal broiler chicks.

The majority of infectious bursal disease virus (IBDV) strains circulating in the broiler chicken industry in Canada are variant strains (varIBDV). Despite high levels of maternally derived antibodies (MtAb), the circulating varIBDVs can establish infection and cause severe immunosuppression in broiler chicks. The objective of this study was to evaluate circulating varIBDVs as broiler breeder vaccine candidates and investigate their protective efficacy against varIBDV challenge in their progeny chicks.

Comparative full genome sequence analysis of wild-type and chicken embryo origin vaccine-like infectious laryngotracheitis virus field isolates from Canada.

Infectious laryngotracheitis (ILT), caused by infectious laryngotracheitis virus (ILTV), occurs sporadically in poultry flocks in Canada. Live attenuated chicken embryo origin (CEO) vaccines are being used routinely to prevent and control ILTV infections. However, ILT outbreaks still occur since vaccine strains could revert to virulence in the field.

Laboratory investigation of cases of fatal bacterial pneumonia in dairy cows.

Objective: Bacterial bronchopneumonia occurs in mature dairy cows but much of the information is extrapolated from knowledge of the disease in calves. The study was prompted by perceptions of an increasing occurrence and a paucity of information on fatal pneumonia in dairy cows in Ontario. The study objectives were to describe the seasonality, main pathogens involved, and suggested predisposing factors for cases of fatal bacterial bronchopneumonia in mature dairy cows submitted for postmortem examination to a diagnostic laboratory, and to evaluate if the frequency of such submissions has increased over time.

Phylogenetic analysis of porcine circovirus 3 circulating in Canadian pigs.

Introduction: Porcine circovirus 3 (PCV3) has been detected in pigs worldwide and associated with several clinical signs.

Methods: To investigate the genetic diversity of PCV3 strains circulating in Canada, 44 PCV3 positive samples from Saskatchewan (2/44), Manitoba (2/44), Quebec (4/44), Alberta (11/44) and Ontario (25/44) submitted to diagnostic laboratories in Canada between 2019 and 2021 were sequenced and analyzed.

Results: Phylogenetic analysis of capsid genes showed that all of the 44 Canadian strains classified into PCV3a and segregated into seven lineages with common amino acid changes observed at A24V, R27K, N56D, T77S, Q98R, L150I (F) and R168K positions.

Virulence of Emerging Arthrotropic Avian Reoviruses Correlates With Their Ability to Activate and Traffic Interferon-γ Producing Cytotoxic CD8 T Cells Into Gastrocnemius Tendon.

Newly emerging arthrotropic avian reoviruses (ARVs) are genetically divergent, antigenically heterogeneous, and economically costly. Nevertheless, the mechanism of emerging ARV-induced disease pathogenesis and potential differences in virulence between virus genotypes have not been adequately addressed. In this study, the life cycle of ARV, including the formation of cytoplasmic ARV neo-organelles, paracrystalline structures, and virus release mechanisms, were characterized in the infected host cell by transmission electron microscopy (TEM).

IN SITU HYBRIDIZATION AND VIRUS CHARACTERIZATION OF SKUNK ADENOVIRUS IN NORTH AMERICAN WILDLIFE REVEALS MULTISYSTEMIC INFECTIONS IN A BROAD RANGE OF HOSTS.

Skunk adenovirus-1 (SkAdV-1) has been reported infecting several North American wildlife species; however, lesions associated with disease have not yet been completely characterized, particularly in porcupines. We describe and characterize the tissue distribution and lesions associated with SkAdV-1 infection in 24 wildlife diagnostic cases submitted between 2015 and 2020, including 16 North American porcupines (Erethizon dorsatum), three striped skunks (Mephitis mephitis), and five raccoons (Procyon lotor), which constitute a new host species. The most common lesion in all species was severe necrotizing bronchopneumonia with (n=12) or without (n=10) interstitial involvement.

Comparative Susceptibility of Madin-Darby Canine Kidney (MDCK) Derived Cell Lines for Isolation of Swine Origin Influenza A Viruses from Different Clinical Specimens.

Madin-Darby canine kidney (MDCK) cells are commonly used for the isolation of mammalian influenza A viruses. The goal of this study was to compare the sensitivity and suitability of the original MDCK cell line in comparison with MDCK-derived cell lines, MDCK.2, MDCK SIAT-1 and MDCK-London for isolation of swine-origin influenza A viruses (IAV-S) from clinical specimens.

Pathogenesis and host responses in lungs and kidneys following Canadian 4/91 infectious bronchitis virus (IBV) infection in chickens.

The infectious bronchitis virus (IBV) 4/91 was one of the common IBV variants isolated in Eastern Canada between 2013 and 2017 from chicken flocks showing severe respiratory and production problems. We designed an in vivo experiment, using specific pathogen free (SPF) chickens, to study the pathogenesis of, and host response to, Canadian (CAN) 4/91 IBV infection. At one week of age, the chickens were infected with 4/91 IBV/Ck/Can/17-038913 isolate.

Genetic characterization of canine distemper virus from wild and domestic animal submissions to diagnostic facilities in Canada.

Traditionally considered an agent affecting domestic dogs, canine distemper virus (CDV) is now well known for an ability to infect a broad range of hosts. In Ontario, domestic dogs are routinely vaccinated and clinical disease attributed to CDV infection in this population is infrequent. CDV has been regularly documented in Ontario wildlife spanning at least 4 decades however, the molecular identity of circulating CDV strains is currently unknown.

Molecular Characterization of 4/91 Infectious Bronchitis Virus Leading to Studies of Pathogenesis and Host Responses in Laying Hens.

Infectious bronchitis virus (IBV) initially establishes the infection in the respiratory tract and then spreads to other tissues depending on its virulence. During 2011-2018, the 4/91 IBV strain was isolated from poultry flocks affected by decreased egg production and quality in Eastern Canada. One of the Canadian 4/91 IBV isolates, IBV/Ck/Can/17-038913, was propagated in embryonated chicken eggs and molecularly characterized using whole genome sequencing.

Classification of porcine reproductive and respiratory syndrome virus in Ontario using Bayesian phylogenetics and assessment of temporal trends.

Porcine reproductive and respiratory syndrome virus (PRRSV) is one of the most important swine viruses globally, including in Ontario, Canada. Understanding the evolution and relation of the various PRRSV genotypes in Ontario can provide insight into the epidemiology of the virus. The objectives of this study were to i) describe the variability of PRRSV genotypes in Ontario swine herds, and ii) evaluate possible groupings based on PRRSV genomic data.