The effects of danofloxacin and tilmicosin on peripheral neutrophils in healthy cattle, on peripheral neutrophils in cattle with induced Pasteurella haemolytica pneumonia, and on body temperature measured via radiotelemetry in cattle with induced Pasteurella haemolytica pneumonia

Three studies are described in this report. In the first study, the effects of danofloxacin and tilmicosin on neutrophil function were examined in healthy mixed-breed weaned beef heifers. Neutrophils were isolated from peripheral blood samples pre- and post-treatment. The neutrophil function assays performed were: random migration under agarose, Cytochrome C reduction, iodination, Staphylococcus aureus ingestion, chemotaxis under agarose, and antibody-independent and antibody-dependent cell-mediated cytotoxicity. The results suggest that at therapeutic drug concentrations, danofloxacin and tilmicosin have little clinically significant effect on bovine neutrophil function. In the second study, a model was developed for the induction of pneumonic pasteurellosis (using 6 x 109 CFU of a log-phase culture of Pasteurella haemolytica intrabronchially) in weaned, pre-conditioned beef calves that consistently produced rectal temperatures of at least 40°C 24 hours after bacterial challenge, a clinical score of ≥1, and measurable lung consolidation. In the third study, Pasteurella pneumonia was induced in weaned beef heifer calves using the model from the second study, and calves were treated with danofloxacin or tilmicosin. Neutrophils were collected at 3, 24 and 48 hours after treatment. Neutrophil function assays were as performed in study 1, and apoptosis was determined using a cell death detection kit. The results suggest that danofloxacin and tilmicosin have no clinically significant effects on neutrophil function or apoptosis. There were also no significant differences in percent lung consolidation among treatments. Significant differences were found between non-challenged calves and the challenged non-treated calves in several neutrophil assays, which were attributed to an effect of the Pasteurella infection. Body temperature was also examined in this study via intravaginally implanted radiotransmitters. Temperatures were monitored prior to challenge until necropsy at 72 hours after treatment. The areas under the curve of the temperature-time plot (and over a baseline temperature established for each animal) calculated for 3-hour intervals were not significantly different for any of the time intervals when challenged animals were compared. Analysis of the mean 3-hour interval temperatures showed significantly higher temperatures for saline-treated as compared to antimicrobialtreated animals for the majority of the time intervals, but no differences were found between the danofloxacin- or tilmicosin-treated animals

Temperatures of storage areas in large animal veterinary practice vehicles in the summer and comparison with drug manufacturers’ storage recommendations

Background: Large animal veterinarians carry drugs in their practice vehicles in storage areas that are not typically refrigerated. The most common upper limits of manufacturers’ storage temperatures for United States (U.S.)-approved non-refrigerated drugs are 25 or 30 °C. Because ambient temperatures in many locations in the U.S. exceed these temperatures during the summer, we measured storage area temperatures over 4 months in the summer of 2013 to evaluate the extent to which labeled storage temperatures are exceeded. Methods: A convenience sample of 12 vehicles from 5 central Texas practices and 12 vehicles from 4 south central Nebraska practices was used. Temperatures were recorded in one drug storage compartment in each vehicle from May 15 – September 16, 2013, at 15-minute intervals using a self-contained, battery operated temperature recording device. Results: The highest temperatures recorded in a storage unit were 54.4 and 47.7 °C in Texas and Nebraska, respectively. The mean temperature recorded across all 24 storage units was 29.1 °C, with a mean of 26.9 °C in Nebraska and 31.4 °C in Texas. In Nebraska, at least one temperature over 25 °C was recorded on a mean of 111/124 days and a mean of 63 % of total logger readings. In Texas, temperatures over 25 °C were recorded on a mean of 123/124 days and a mean of 95 % of total logger readings. Conclusions: Temperatures in storage units in participating veterinary practice vehicles exceeded labeled drug storage temperatures a significant portion of the summer of 2013. More research is needed to determine whether these excursions above the manufacturers’ recommended storage temperatures alter efficacy of stored drugs

Building searching skills early in the veterinary school curriculum to support evidence- based practice

Presentation given at the 2022 EAHIL Conference in Rotterdam, the NetherlandsEuropean Association for Health Information and Librarie

Proper Use of Sulfonamides in Market Show Animals

4 pp., 1 tableWhen administering a drug to a show animal, the owner is responsible for ensuring that there will be no drug residues in the animal's urine when it is tested at a show. Sulfonamides are of special concern because, even when they are administered correctly and the proper withdrawal times are observed, their residues can remain. This publication explains how and why sulfonamides are used and what you must do to maintain an animal's show eligibility

Temperatures of storage areas in large animal veterinary practice vehicles in the summer and comparison with drug manufacturers’ storage recommendations

Background: Large animal veterinarians carry drugs in their practice vehicles in storage areas that are not typically refrigerated. The most common upper limits of manufacturers’ storage temperatures for United States (U.S.)-approved non-refrigerated drugs are 25 or 30 °C. Because ambient temperatures in many locations in the U.S. exceed these temperatures during the summer, we measured storage area temperatures over 4 months in the summer of 2013 to evaluate the extent to which labeled storage temperatures are exceeded. Methods: A convenience sample of 12 vehicles from 5 central Texas practices and 12 vehicles from 4 south central Nebraska practices was used. Temperatures were recorded in one drug storage compartment in each vehicle from May 15 – September 16, 2013, at 15-minute intervals using a self-contained, battery operated temperature recording device. Results: The highest temperatures recorded in a storage unit were 54.4 and 47.7 °C in Texas and Nebraska, respectively. The mean temperature recorded across all 24 storage units was 29.1 °C, with a mean of 26.9 °C in Nebraska and 31.4 °C in Texas. In Nebraska, at least one temperature over 25 °C was recorded on a mean of 111/124 days and a mean of 63 % of total logger readings. In Texas, temperatures over 25 °C were recorded on a mean of 123/124 days and a mean of 95 % of total logger readings. Conclusions: Temperatures in storage units in participating veterinary practice vehicles exceeded labeled drug storage temperatures a significant portion of the summer of 2013. More research is needed to determine whether these excursions above the manufacturers’ recommended storage temperatures alter efficacy of stored drugs

Using telehealth clinical case vignettes to enhance clinical confidence and competence in veterinary students

Veterinarians contribute substantially to the health of their patients and enhance the communities in which they live. Delivery of veterinary curricula continues to evolve to ensure that veterinary graduates are prepared to meet their professional obligations on Day One of their careers. In this study, veterinary practitioners were recruited to deliver telehealth case rounds to veterinary students at Kansas State University and Texas A&M University. Case discussions were hosted virtually once per month in the 2020–2021 and 2021–2022 academic years for a total of 16 sessions. Each presenting practitioner was instructed to develop a brief presentation for a case routinely seen in their practice, and to discuss important clinical decision points in diagnosis, treatment and management. Cases could also highlight important ethical or communication issues encountered in veterinary medicine. The overall goals of this project were to increase the quantity and diversity of clinical cases to which veterinary students were exposed during their professional training and to evaluate the feasibility and acceptability of telehealth technology as a teaching strategy. Student participants were surveyed to determine the effectiveness of telehealth sessions in increasing overall confidence and competence in case management, and veterinary presenters were surveyed to determine motivations for participating in the project and perceived value of the telehealth sessions. More than 95% of students indicated that participation in telehealth sessions increased their clinical confidence and competence. Presenting practitioners unanimously indicated that they would participate in similar instruction in the future. Recommendations are provided to improve the educational experience for future adopters of telehealth teaching sessions

Synovial pharmacokinetics of tulathromycin, gamithromycin and florfenicol after a single subcutaneous dose in cattle

Background: Deep digital septic conditions represent some of the most refractory causes of severe lameness in cattle. The objective of this study was to determine the distribution of tulathromycin, gamithromycin and florfenicol into the synovial fluid of the metatarsophalangeal (MTP) joint of cattle after single subcutaneous administration of drug to evaluate the potential usefulness of these single-dose, long-acting antimicrobials for treating bacterial infections of the joints in cattle. Results: Twelve cross-bred beef cows were randomly assigned to one of the drugs. Following subcutaneous administration, arthrocentesis of the left metatarsophalangeal joint was performed at various time points up to 240 hours post-injection, and samples were analyzed for drug concentration. In synovial fluid, florfenicol pharmacokinetic parameters estimates were: mean Tmax 7 +/− 2 hours, mean t½ 64.9 +/− 20.1 hours and mean AUC0-inf 154.0 +/− 26.2 ug*h/mL. Gamithromycin synovial fluid pharmacokinetic parameters estimates were: mean Tmax 8 hours, mean t½ 77.9 +/− 30.0 hours, and AUC0-inf 6.5 +/− 2.9 ug*h/mL. Tulathromycin pharmacokinetic parameters estimates in synovial fluid were: Tmax 19 +/− 10 hours, t½ 109 +/− 53.9 hours, and AUC0-inf 57.6 +/− 28.2 ug h/mL. Conclusions: In conclusion, synovial fluid concentrations of all three antimicrobials were higher for a longer duration than that of previously reported plasma values. Although clinical data are needed to confirm microbiological efficacy, florfenicol achieved a synovial fluid concentration greater than the MIC90 for F. necrophorum for at least 6 days.The open access fee for this work was funded through the Texas A&M University Open Access to Knowledge (OAK) Fund

Metronidazole for the treatment of Tritrichomonas foetus in bulls

Abstract Background: Tritrichomonas foetus is a sexually transmitted protozoon that causes reproductive failure, among cattle, so disruptive that many western US states have initiated control programs. Current control programs are based on the testing and exclusion of individual bulls. Unfortunately, these programs are utilizing screening tests that are lacking in sensitivity. Blanket treatment of all the exposed bulls and adequate sexual rest for the exposed cows could provide a more viable disease control option. The objectives of this study were twofold. The first objective was to demonstrate effectiveness for metronidazole treatment of a bull under ideal conditions and with an optimized treatment regime. This type of study with a single subject is often referred to as an n-of-1 or single subject clinical trial. The second objective of the current study was to review the scientific basis for the banning of metronidazole for use in Food Animals by the Animal Medicinal Drug Use Clarification Act of 1994 (AMDUCA). Results: Results from an antimicrobial assay indicated that metronidazole at a concentration of 0.5 μg/mL successfully eliminated in vitro protozoal growth of bovine Tritrichomonas foetus. The estimated effective intravenous dose was two treatments with 60 mg/kg metronidazole, 24 h apart. A bull that had tested positive for Tritrichomonas foetus culture at weekly intervals for 5 weeks prior to treatment was negative for Tritrichomonas foetus culture at weekly intervals for five consecutive weeks following this treatment regimen. An objective evaluation of the published evidence on the potential public health significance of using metronidazole to treat Tritrichomonas foetus in bulls provides encouragement for veterinarians and regulators to consider approaches that might lead to permitting the legal use of metronidazole in bulls. Conclusion: The study demonstrated successful inhibition of Tritrichomonas foetus both in vitro and in vivo with metronidazole. The current status of metronidazole is that the Animal Medicinal Drug Use Clarification Act of 1994 prohibits its extra-label use in food-producing animals. Veterinarians and regulators should consider approaches that might lead to permitting the legal use of metronidazole in bulls. Keywords: Tritrichomonas feotus, metronidazole, cattleTexas A&M University Department of Large Animal Clinical Sciences

Demographic factors associated with joint supplement use in dogs from the Dog Aging Project

Osteoarthritis (OA) is one of the most prevalent age-related chronic conditions that afflict companion dogs, and multiple joint supplements are available to prevent or treat OA, though the efficacy of these treatments is controversial. While the demographic factors that are associated with OA diagnosis are well established, the factors that are associated with joint supplement use are not as well studied. Using data collected from the Dog Aging Project, we analyzed owner survey responses regarding joint supplement administration and OA diagnosis for 26,951 adult dogs. In this cross-sectional analysis, logistic regression models and odds-ratios (OR) were employed to determine demographic factors of dogs and their owners that were associated with joint supplement administration. Forty percent of adult dogs in our population were given some type of joint supplement. Perhaps not surprisingly, dogs of older age, larger size, and those that were ever overweight were more likely to receive a joint supplement. Younger owner age, urban living, owner education, and feeding commercial dry food were associated with a reduced likelihood of administration of joint supplements to dogs. Interestingly, mixed breed dogs were also less likely to be administered a joint supplement (OR: 0.73). Dogs with a clinical diagnosis of OA were more likely to receive a joint supplement than those without a reported OA diagnosis (OR: 3.82). Neutered dogs were more likely to have a diagnosis of OA, even after controlling for other demographic factors, yet their prevalence of joint supplement administration was the same as intact dogs. Overall, joint supplement use appears to be high in our large population of dogs in the United States. Prospective studies are needed to determine if joint supplements are more commonly administered as a preventative for OA or after an OA clinical diagnosis

EBVM Teaching Materials

These documents from the collection "Assignments, templates, and rubrics for teaching the skills of evidence-based veterinary medicine in veterinary professional programs" are edited by Virginia R. Fajt and Heather K. Moberly at Texas A&M University and freely available in the institutional repository. They are licensed with a Creative Commons CC-BY-NC-SA license. You may use the materials as is. You may also remix, transform and build on the material as long as you give credit, provide a link to the license, and indicate if changes were made; you may not apply any terms or measures that would restrict others from doing anything the copyright license permits. (See https://creativecommons.org/licenses/by-nc-sa/4.0/ for details.) Acknowledgements: The following individuals have provided content or feedback on these assignments: Christine Budke and Annette O’Connor. The authors also acknowledge that some of the products were adapted from the following works: S.P. Arlt and W. Heuwieser, Journal of Veterinary Medical Education, 38(2), 135-140, 2011; A. O’Connor and V.R. Fajt, Vet Clinics of North America: Food Animal, 31(1), 2015; S.P. Arlt and W. Heuwieser, The Staircase of Evidence – a New Metaphor Displaying the Core Principles of Evidence-based Veterinary Medicine, Veterinary Evidence, 2016, 1(1), https://doi.org/10.18849/ve.v1i1.18.The documents contained in this collection are assignments, templates, and rubrics used for teaching the skills of evidence-based veterinary medicine in a 4-year veterinary professional program. They are grouped by unit within a semester, starting with the first semester of the first year of the program and ending with assignments used in the last clinical year on two different clinical rotations. The skills we focus on are writing PICO-style clinical questions, searching the biomedical literature for evidence, critically appraising evidence, and applying evidence to the clinical question