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Retrospective serological and case diagnostic data of endemic bluetongue virus (BTV) and epizootic hemorrhagic disease virus (EHDV) provide evidence of viral transmission among livestock and wildlife from 2016 in Kansas and Nebraska. Serological testing of mature cattle in nine distinct regional zones of Kansas revealed 76% to 100% had detectable antibodies to BTV and/or EHDV. Specimens tested in the Kansas Veterinary Diagnostic Laboratory (55 submissions) were 51% test positive for antibodies to BTV and/or EHDV. Specimens tested in the Nebraska Veterinary Diagnostic Center (283 submissions) were 25% test positive for antibodies to BTV and/or EHDV. Low disease incidence in white-tailed deer and other susceptible wild ungulates was observed during 2016. However, there were no confirmed reports of disease in livestock in either state. The reasons for emergence of significant clinical disease in livestock and wildlife populations remain undefined.

The SARS-CoV-2 virus is the causative agent of COVID-19 and has undergone continuous mutations throughout the pandemic. The more transmissible Omicron variant has quickly spread and is replacing the Delta variant as the most prevalent strain globally, including in the United States. A new molecular assay that can detect and differentiate both the Delta and Omicron variants was developed. A collection of 660,035 SARS-CoV-2 full- or near-full genomes, including 169,454 Delta variant and 24,202 Omicron variant strains, were used for primer and probe designs. In silico data analysis predicted an assay coverage of >99% of all strains, including >99% of the Delta and >99% of Omicron strains. The Omicron variant differential test was designed based on the Δ31-33 aa deletion in the N-gene, which is present in the original B.1.1.529 main genotype, BA.1, as well as in BA.2 and BA.3 subtypes. Therefore, the assay should detect the majority of all Omicron variant strains. Standard curves generated with human clinical samples indicated that the PCR amplification efficiencies were 104%, 90.7% and 90.4% for the Omicron, Delta, and non-Delta/non-Omicron wild-type genotypes, respectively. Correlation coefficients of the standard curves were all >0.99. The detection limit of the assay was 14.3, 32.0, and 21.5 copies per PCR reaction for Omicron, Delta, and wild-type genotypes, respectively. The assay was designed to specifically detect SAR-CoV-2 strains. Selected samples with Omicron, Delta and wild-type genotypes identified by the RT-qPCR assay were also confirmed by sequencing. The assay did not detect any animal coronavirus-positive samples that were tested. Human nasal swab samples that previously tested positive (n = 182) or negative (n = 42) for SARS-CoV-2 by the ThermoFisher TaqPath COVID-19 Combo Kit, produced the same result with the new assay. Among positive samples, 55.5% (101/182), 23.1% (42/182), and 21.4% (39/182) were identified as Omicron, Delta, and non-Omicron/non-Delta wild-type genotypes, respectively., (© 2022 Wiley-VCH GmbH.)

Giardia spp. is a protozoal parasite capable of causing diarrhea in mammals. Certain Giardia assemblages are potentially zoonotic. As part of a public health study, a questionnaire-based cross-sectional web survey was distributed among U.S. small and mixed animal veterinarians to assess the perceived prevalence, the preferred testing and treatment methods, the recommended control measures, and the information communicated about the zoonotic potential of canine giardiasis. Between February and June 2021, over 123 veterinarians from 31 U.S. states participated in the survey. 77% of surveyed veterinarians indicated that they are aware of the prevalence of canine giardiasis in their areas of practice. 52% of veterinarians reported that they test all symptomatic dogs for Giardia, while 42.4% test dogs only some of the time. The preferred confirmatory tests were in the following order: commercial diagnostic lab > in-clinic SNAP® Test > in-clinic Direct Smear > in-clinic Fecal Flotation > state/university diagnostic lab. Several combinations of tests are frequently used to confirm diagnosis. Although there are no labelled products available for treating canine giardiasis in the U.S., 54% of respondents preferred using both fenbendazole and metronidazole simultaneously, 15% reported using fenbendazole only, and 20% reported using metronidazole only. 77.0% of respondents indicated they have dealt with treatment refractory cases often or rarely. 92.6% of veterinarians reported mentioning environmental control to pet owners sometimes or always, which included bathing the infected pet, cleaning toys/bowls/bedding, cleaning floors, and bathing other pets. 73.6% of veterinarians communicated to their clients that Giardia was potentially zoonotic. There are conflicting opinions on the importance of zoonotic transmission between humans and canines available to the general veterinary practitioner. Given that children are at a higher risk of developing Giardia infections, it is important for veterinarians to preserve the health of canine companions to protect their human owners. Thus, the contributions of veterinarians in managing canine giardiasis within the framework of One Health initiatives should not be overlooked., (Copyright © 2022 Elsevier B.V. All rights reserved.)

We report two near-complete bovine respiratory syncytial virus genome sequences collected from 10-month-old cattle with respiratory disease in Kansas in December 2021. No other respiratory pathogens were confirmed in the samples. These genome sequences update the currently circulating BRSV field strains in the United States.

Reverse transcription fluorescence resonance energy transfer-polymerase chain reaction (FRET-PCRs) were designed against the two most common mutations in severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) (A23403G in the spike protein; C14408T in the RNA-dependent RNA polymerase). Based on high-resolution melting curve analysis, the reverse transcription (RT) FRET-PCRs identified the mutations in american type culture collection control viruses, and feline and human clinical samples. All major makes of PCR machines can perform melting curve analysis and thus further specifically designed FRET-PCRs could enable active surveillance for mutations and variants in countries where genome sequencing is not readily available., (© 2021 Wiley Periodicals LLC.)

Research investigating the effects of feeding raw or pasteurized nonsaleable milk (NSM) on heifers' performance beyond the period of supplementation is limited. This study aimed to examine the effects of type of milk [NSM or milk replacer (MR)] and pasteurization of NSM on preweaning and first-lactation performance of heifers born with low (<36.3 kg) or normal birth weight (≥36.3 kg). Holstein heifers (n = 154) were sequentially assigned to 1 of 3 treatments: MR, pasteurized NSM, or raw NSM. Heifers assigned to raw NSM were fed raw colostrum, whereas heifers assigned to MR and pasteurized NSM were fed pasteurized colostrum. The low birth weight heifers were fed 1.4 L at each feeding until they reached 36.3 kg body weight, whereas normal birth weight heifers were fed 1.9 L at each feeding. A grain mix starter was offered throughout the study. Heifers were weaned ≥42 d old if consuming at least 0.9 kg/d of starter for 3 consecutive days. Data were analyzed with the MIXED procedure of SAS (SAS Institute Inc., Cary, NC), and the basic model included milk treatments, birth weight group, and treatment × birth weight group. The low birth weight heifers fed raw colostrum and NSM versus pasteurized colostrum and NSM had lower serum protein concentrations. Heifers fed MR versus NSM had or tended to have greater concentrations of hematocrit, red blood cells, and eosinophils but lesser concentrations of platelets, although some of those responses were temporary. Pasteurization tended to increase blood lymphocyte concentrations. Heifers with normal birth weight had greater concentrations of blood neutrophils, lymphocytes, and monocytes, compared with low birth weight heifers. For the first 42 d of life, low birth weight heifers fed pasteurized versus raw NSM had greater weight gain, grain intake, and feed efficiency and were weaned earlier (hazard ratio for weaning by 56 d: 2.90). These pasteurization effects for low birth weight heifers tended to be sustained through 24 wk of age, indicated by greater weight gain and hip height growth. In their first lactation, low birth weight heifers produced less mature-equivalent (MEq) protein and tended to produce less MEq milk and fat than normal birth weight heifers. However, the negative effects of low birth weight on MEq milk and fat yield was only evident in heifers fed raw NSM, whereas the performance of low birth weight heifers was similar to that of normal birth weight when fed MR or pasteurized NSM. These findings confirm that calf management practices influence future performance; in this case, failing to pasteurize milk and colostrum for low birth weight heifers had effects that remained apparent for more than 2 years., (Copyright © 2021 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)

The need for consortial programs to provide advanced education in food animal veterinary production medicine has been recognized and lauded for nearly three decades. This article describes one effort to create a dairy production medicine curriculum funded by a United States Department of Agriculture (USDA) Higher Education Challenge Grant. This National Center of Excellence in Dairy Production Medicine Education for Veterinarians is housed at the Dairy Education Center of the University of Minnesota and the project was a collaboration of the University of Minnesota, the University of Illinois, the University of Georgia, and Kansas State University. The article reviews the need for innovative ways to educate students who will optimally serve the dairy industry, provides a broad overview of the process of developing and delivering the eight-week dairy production medicine curriculum, and describes the challenges faced and lessons learned as a result of offering such a program.

Streptococcus equi subsp. equi is a Gram positive bacterial pathogen commonly associated with strangles in horses, a respiratory disease characterized by abscessation of submandibular and retropharyngeal lymph nodes which can lead to obstruction of the airway. Several real-time PCR (qPCR) assays have been developed for detection of S. equi from horses with many targeting conserved regions of the S. equi cell wall-associated M-protein (SeM), a major virulence factor and immunogen of S. equi. Our objective was to develop a nested PCR (nPCR) targeting SeM and an 18S rRNA internal control gene for detection of S. equi from horses with potential improvement in detection sensitivity compared to a qPCR. Primers and probes from the Kansas State Veterinary Diagnostic Laboratory (KSVDL) S. equi clinical testing assay were utilized for all qPCR testing. Primers flanking the SeM qPCR target region were selected for an initial end-point PCR step of the nested assay; PCR product from the end-point reaction then served as template for the qPCR reaction step of the nested assay. Sample nucleic acid was also tested directly with qPCR to allow for assay comparison. Nucleic acid from clinical specimens (n = 188) submitted to KSVDL were tested in parallel with each assay. The nPCR and qPCR assays identified 22.9% (43/188) and 13.3% (25/188) of samples positive for S. equi, respectively. None of the samples positive by qPCR were negative by nPCR. The PCR products from all positive samples were submitted for DNA sequencing. Each of the 25 samples positive by both assays had a high nucleotide identity match (>96%) to the SeM gene. Among the samples positive by nPCR but negative by qPCR, 17 of 18 were sequence confirmed for SeM at greater than 96% nucleotide identity. Based on the nPCR Ct (37.8) of the one sequence un-confirmed case, it is likely that the S. equi bacterial load in this sample was below the necessary concentration for successful sequencing. Limit of detection (LOD) for the nPCR was established at a Ct of 37, and based both on the LOD of the qPCR assay (Ct of 37), as determined by standard curve data, and on the highest nPCR Cts (~37) of clinical samples able to result in SeM sequence-confirmation. As demonstrated by sequencing confirmation, the nPCR assay targeting the SeM gene is highly specific to S. equi. The increased sensitivity of the nPCR, compared to the qPCR, may reduce the number of false negative sample results in clinical testing and provide a superior detection method during low bacterial shedding periods., Competing Interests: Declaration of Competing Interest Authors declare that there are no competing interests to this research., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Infectious bovine keratoconjunctivitis (IBK), also known as pinkeye, is one of the most common eye diseases in cattle. Several pathogens have been associated with IBK cases, however, Moraxella bovis, Moraxella bovoculi, Mycoplasma bovis, Mycoplasma bovoculi and bovine herpesvirus type 1 (BHV-1) are most frequently observed. A multiplex real-time PCR assay using two reactions was developed for the detection and differentiation of these five pathogens. Detection sensitivities of the multiplex assays were compared to singleplex reactions testing for the same targets. Correlation coefficients (R 2 ) of >0.99, and PCR efficiencies between 92 and 106% were demonstrated in all singleplex and multiplex real-time PCR reactions. The limits of detection (LOD) of multiplex assays for Moraxella bovis, Moraxella bovoculi, Mycoplasma bovis, Mycoplasma bovoculi and BHV-1 were 19, 23, 25, 24 and 26 copies per reaction, respectively. No cross amplification was observed for specificity testing of 179 IBK positive clinical samples and 55 non-target clinical samples. Percentage of clinical samples positive for Mycoplasma bovoculi, Moraxella bovoculi, Moraxella bovis, BHV-1 and Mycoplasma bovis were 88.8% (159/179), 75.9% (136/179), 60.3% (108/179), 11.7% (21/179) and 10.0% (18/179), respectively. Moraxella bovis, Moraxella bovoculi and Mycoplasma bovoculi were more prevalent than Mycoplasma bovis and BHV-1 in IBK samples collected from animals in this study population. Our data indicates that the multiplex real-time PCR panel assay is highly sensitive and highly specific for the detection and differentiation of the five major pathogens associated with bovine pinkeye., (Copyright © 2019 Elsevier B.V. All rights reserved.)

We identified influenza C virus (ICV) in samples from US cattle with bovine respiratory disease through real-time PCR testing and sequencing. Bovine ICV isolates had high nucleotide identities (≈98%) with each other and were closely related to human ICV strains (≈95%). Further research is needed to determine bovine ICV's zoonotic potential.

Influenza C virus (ICV) has been identified for the first time from bovine respiratory disease complex (BRDC) samples in the United States. Here, we report the complete genome sequence of the strain C/bovine/Montana/12/2016, identified from a nasal swab sample collected from a sick calf with clinical signs of respiratory disease in Montana.

Mollicutes nasal swab culture status and potential associations with health outcomes were determined in beef feeder calves. Mollicutes culture was positive in 7.6% (22/291) of calves at arrival and in 26.2% (34/130) of calves at first disease treatment. Positive Mollicutes culture at first treatment was associated with increased odds for subsequent retreatment or death.