Beef Cow-calf Vaccine Knowledge Translation and Transfer (KTT) Project: Summary report on producer, veterinarian, and working group surveys regarding vaccine usage and recommendations.

Objective: The overall aim of this project was to create educational materials to support beef veterinarians and cow-calf producers in maximizing appropriate uptake of vaccine use in western Canada. The specific objective of the surveys reported here was to document current vaccine use by producers and vaccination recommendations by veterinarians and other industry stakeholders. Population: Cow-calf producers and veterinarians involved in the western Canadian beef cow-calf sector. Results: Surveys of western Canadian cow-calf producers and veterinarians were conducted in the fall of 2021 regarding current vaccine usage and recommendations, respectively. Uptake of beef cow-calf vaccines deemed "core" vaccines by the American Association of Bovine Practitioners (AABP) varied across cow-calf producers, and recommendations varied across veterinarians responding to the survey. Thirty members of the project working group, consisting of cow-calf producers, veterinarians, academics, and vaccine manufacturers, were also surveyed regarding vaccine recommendations. The recommendations of the working group aligned with AABP recommendations for core and risk-based vaccines. Conclusions: Uptake of core beef vaccines was not complete across the producers surveyed. Therefore, education of beef cow-calf producers regarding the importance of core vaccines is required. Clinical relevance: Findings from these surveys will guide creation of educational materials to promote the use of appropriate beef cow-calf vaccines.

Projet d'application et de transfert des connaissances sur les vaccins (KTT) du Beef Cattle Research Council (BCRC) : rapport sommaire sur les sondages auprès des producteurs, des vétérinaires et des groupes de travail concernant l'utilisation des vaccins et les recommandations. Objectif: L'objectif général de ce projet était de créer du matériel éducatif pour aider les vétérinaires de bovins de boucherie et les éleveurs de vaches-veaux à maximiser l'adoption appropriée de l'utilisation des vaccins dans l'Ouest canadien. L'objectif spécifique des enquêtes rapportées ici était de documenter l'utilisation actuelle des vaccins par les producteurs et les recommandations de vaccination par les vétérinaires et d'autres intervenants de l'industrie. Population: Éleveurs de vaches-veaux et vétérinaires impliqués dans le secteur des vaches-veaux de boucherie de l'Ouest canadien. Résultats: Des sondages auprès des éleveurs de vaches-veaux et des vétérinaires de l'Ouest canadien ont été menés à l'automne 2021 concernant l'utilisation actuelle des vaccins et les recommandations, respectivement. L'adoption des vaccins pour vaches-veaux de boucherie considérés comme des vaccins « de base ¼ par l'American Association of Bovine Practitioners (AABP) variait selon les producteurs de vaches-veaux, et les recommandations variaient selon les vétérinaires répondant à l'enquête. Trente membres du groupe de travail du projet, composé de producteurs de vaches-veaux, de vétérinaires, d'universitaires et de fabricants de vaccins, ont également été interrogés sur les recommandations en matière de vaccins. Les recommandations du groupe de travail sont alignées sur les recommandations de l'AABP pour les vaccins de base et basés sur les risques. Conclusion: L'adoption des vaccins de base pour le bœuf n'était pas complète parmi les producteurs interrogés. Par conséquent, l'éducation des producteurs de vaches-veaux de boucherie concernant l'importance des vaccins de base est nécessaire. Pertinence clinique: Les résultats de ces enquêtes guideront la création de matériel pédagogique pour promouvoir l'utilisation de vaccins appropriés dans les élevages vaches-veaux de boucherie.(Traduit par Dr Serge Messier).

Assessing anthelmintic resistance risk in the post-genomic era: a proof-of-concept study assessing the potential for widespread benzimidazole-resistant gastrointestinal nematodes in North American cattle and bison.

As genomic research continues to improve our understanding of the genetics of anthelmintic drug resistance, the revolution in DNA sequencing technologies will provide increasing opportunities for large-scale surveillance for the emergence of drug resistance. In most countries, parasite control in cattle and bison has mainly depended on pour-on macrocyclic lactone formulations resulting in widespread ivermectin resistance. Consequently, there is an increased interest in using benzimidazole drugs which have been used comparatively little in cattle and bison in recent years. This situation, together with our understanding of benzimidazole resistance genetics, provides a practical opportunity to use deep-amplicon sequencing to assess the risk of drug resistance emergence. In this paper, we use deep-amplicon sequencing to scan for those mutations in the isotype-1 ß-tubulin gene previously associated with benzimidazole resistance in many trichostrongylid nematode species. We found that several of these mutations occur at low frequency in many cattle and bison parasite populations in North America, suggesting increased use of benzimidazole drugs in cattle has the potential to result in widespread emergence of resistance in multiple parasite species. This work illustrates a post-genomic approach to large-scale surveillance of early emergence of anthelmintic resistance in the field.

Mycoplasma bovis-Induced Inhibition of Bovine Peripheral Blood Mononuclear Cell Proliferation Is Ameliorated after Blocking the Immune-Inhibitory Programmed Death 1 Receptor.

Mycoplasma bovis-induced immune suppression is a major obstacle faced by the host for controlling infections. M. bovis impairment of antigen-specific T-cell responses is achieved through inhibiting the proliferation of peripheral blood mononuclear cells (PBMCs). This impairment may contribute to the persistence of M. bovis infection in various sites, including lungs, and its systemic spread to various organs such as joints, with the underlying mechanisms remaining elusive. Here, we elucidated the role of the immune-inhibitory receptor programmed death 1 (PD-1) and its ligand (PD-L1) in M. bovis infection. Flow cytometry (FCM) analyses revealed an upregulation of PD-L1 expression on tracheal and lung epithelial cell lines after M. bovis infection. In addition, we found increased PD-L1 expression on purified lung lavage macrophages following M. bovis infection by FCM and determined its localization by immunofluorescence analysis comparing infected and control lung tissue sections. Moreover, M. bovis infection increased the expression of the PD-1 receptor on total PBMCs and in gated CD4+ and CD8+ T-cell subpopulations. We demonstrated that M. bovis infection induced a significant decrease in CD4+ PD-1INT and CD8+ PD-1INT subsets with intermediate PD-1 expression, which functioned as progenitor pools giving rise to CD4+ PD-1HIGH and CD8+ PD-1HIGH subsets with high PD-1 expression levels. We blocked PD-1 receptors on PBMCs using anti-PD-1 antibody at the beginning of infection, leading to a significant restoration of the proliferation of PBMCs. Taken together, our data indicate a significant involvement of the PD-1/PD-L1 inhibitory pathway during M. bovis infection and its associated immune exhaustion, culminating in impaired host immune responses.

Mycoplasma bovis isolates recovered from cattle and bison (Bison bison) show differential in vitro effects on PBMC proliferation, alveolar macrophage apoptosis and invasion of epithelial and immune cells.

In the last few years, several outbreaks of pneumonia, systemically disseminated infection, and high mortality associated with Mycoplasma bovis (M. bovis) in North American bison (Bison bison) have been reported in Alberta, Manitoba, Saskatchewan, Nebraska, New Mexico, Montana, North Dakota, and Kansas. M. bovis causes Chronic Pneumonia and Polyarthritis Syndrome (CPPS) in young, stressed calves in intensively-managed feedlots. M. bovis is not classified as a primary pathogen in cattle, but in bison it appears to be a primary causative agent with rapid progression of disease with fatal outcomes and an average 20% mature herd mortality. Thus, there is a possibility that M. bovis isolates from cattle and bison differ in their pathogenicity. Hence, we decided to compare selected cattle isolates to several bison isolates obtained from clinical cases. We show differences in modulation of PBMC proliferation, invasion of trachea and lung epithelial cells, along with modulation of apoptosis and survival in alveolar macrophages. We concluded that some bison isolates showed less inhibition of cattle and bison PBMC proliferation, were not able to suppress alveolar macrophage apoptosis as efficiently as cattle isolates, and were more or less invasive than the cattle isolate in various cells. These findings provide evidence about the differential properties of M. bovis isolated from the two species and has helped in the selection of bison isolates for genomic sequencing.

In vitro antimicrobial susceptibility of Mycoplasma bovis clinical isolates recovered from bison (Bison bison).

Mycoplasma bovis is a pathogen globally affecting cattle and bison herds, causing pneumonia, arthritis, mastitis, abortions, and other symptoms, leading to huge economic losses. Many studies have been done regarding the antimicrobial susceptibility of M. bovis isolated from cattle, but no such study is available for isolates recovered from bison. For the first time, in vitro susceptibilities of 40 M. bovis clinical isolates collected from bison herds in Canada are reported here. Minimal inhibitory concentration (MIC) values were determined using Sensititre® plates. The most effective MIC50 and MIC90 were for spectinomycin (1 and >64 µg/mL), tiamulin (1 and >32 µg/mL), and tulathromycin (16 and 64 µg/mL), whereas tetracyclines, fluoroquinolones, and florfenicol failed to inhibit growth of M. bovis bison isolates. Isolates were nonsusceptible to tetracyclines (100%), fluoroquinolones (97.5%), and tilmicosin (100%), whereas the highest susceptibility of bison clinical isolates was seen with spectinomycin (95%) and tulathromycin (67.5%). Two lung isolates (Mb283 and 348) were found resistant to both spectinomycin and tulathromycin. These results show a marked difference in antimicrobial susceptibility of bison isolates as compared with previously reported and laboratory reference cattle isolates, emphasizing the necessity of testing antimicrobial susceptibility of M. bovis bison isolates and to generate better therapeutic regime for improved recovery chances for infected bison herds across North America.

Limited efficacy of Fever Tag(®) temperature sensing ear tags in calves with naturally occurring bovine respiratory disease or induced bovine viral diarrhea virus infection.

Temperature sensing ear tags were tested in 1) auction-derived calves with 50% incidence of bovine respiratory disease, and 2) specific pathogen-free calves infected with bovine virus diarrhea virus. There were no false positives, but tag placement, probe displacement, and a high threshold for activation all contributed to failure to reliably detect sick calves.

Efficacité limitée des étiquettes d'oreille Fever TagMDpour mesurer la température chez les veaux atteints de maladies respiratoires d'origine naturelle ou d'une infection induite par le virus de la diarrhée virale des bovins. Les étiquettes d'oreille pour mesurer la température ont été testées chez 1) des veaux provenant d'encans ayant 50 % d'incidence de maladies respiratoires et 2) des veaux exempts d'agents pathogènes spécifiques infectés par le virus de la diarrhée virale bovine. Il n'y avait aucun faux positif, mais le placement des étiquettes, le déplacement de la sonde et un seuil d'activation élevé ont tous contribué à l'échec de la détection fiable des veaux malades.(Traduit par Isabelle Vallières).

Cardiopulmonary effects of administration of a combination solution of xylazine, guaifenesin, and ketamine or inhaled isoflurane in mechanically ventilated calves.

OBJECTIVE: To compare the cardiopulmonary effects of administration of a solution of xylazine, guaifenesin, and ketamine (XGK) or inhaled isoflurane in mechanically ventilated calves undergoing surgery. ANIMALS: 13 male calves 2 to 26 days of age. Procedures-In calves in the XGK group, anesthesia was induced (0.5 mL/kg) and maintained (2.5 mL/kg/h) with a combination solution of xylazine (0.1 mg/mL), guaifenesin (50 mg/mL), and ketamine (1.0 mg/mL). For calves in the isoflurane group, anesthesia was induced and maintained with isoflurane in oxygen. The rates of XGK infusion and isoflurane administration were adjusted to achieve suitable anesthetic depth. All calves received 100% oxygen and were mechanically ventilated to maintain end-tidal carbon dioxide concentrations from 35 to 40 mm Hg and underwent laparoscopic bladder surgery through an abdominal approach. Cardiopulmonary variables were measured before induction and at intervals up to 90 minutes after anesthetic induction. RESULTS: The quality of induction was excellent in all calves. The XGK requirements were 0.57 +/- 0.18 mL/kg and 2.70 +/- 0.40 mL/kg/h to induce and maintain anesthesia, respectively. Heart rate was significantly lower than baseline throughout the anesthetic period in the XGK group. Systolic arterial blood pressure was significantly higher in the XGK group, compared with the isoflurane group, from 5 to 90 minutes. Cardiac index was lower than baseline in both groups. Differences between groups in cardiac index and arterial blood gas values were not significant. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of XGK resulted in excellent anesthetic induction and maintenance with cardiopulmonary alterations similar to those associated with isoflurane in mechanically ventilated calves.