Highlights of recent clinically relevant papers

This retrospective case series by UK-based Melissa Kamps and Safia Barakzai described the outcome for 20 cases after dental repulsion using small diameter repulsion pins. Clinical records of horses that underwent cheek tooth repulsion were reviewed (2014–2023). Inclusion criteria included: mandibular or maxillary cheek tooth extraction where oral extraction failed and repulsion was used to complete extraction, and where clinical follow-up information was available. Repulsions were carried out under sedation with a regional nerve block or under a short general anaesthetic, using a small diameter repulsion pin (3–5 mm). Intraoperative radiographs facilitated instrument placement. The alveolus was packed with polymethyl methacrylate post-extraction. Horses were re-examined at 4–6 weeks post-operatively. The 20 cases had a mean age of 10.3 years old (range: 5–16 years). The majority (75%) of teeth had pre-existing dental fractures. Maxillary (n = 15) and mandibular cheek teeth (n = 5) were all successfully repulsed, with 16 cases performed with the horse standing and four with the horse under general anaesthesia. Intraoperative complications included damage to the mandibular bone (n = 1). Short-term complications (n = 2) included superficial surgical site infection, and dehiscence of one sinus flap. Long-term complications included the recurrence of sinusitis (n = 1) and small intra-alveolar fragments causing persistent biting problems in another patient. When oral extraction fails, cheek tooth repulsion using small diameter repulsion pins is an effective extraction technique. The total intra and post-operative complication rate was 25%. This study by Giovane Olivo and co-workers in Brazil investigated the prevalence of methicillin-resistant Staphylococcus spp. (MRS) in hospitalised horses and contacting personnel (veterinarians and staff) and assessed possible interspecies transmission in a teaching veterinary hospital. Nasal swabs from horses (n = 131) and humans (n = 35) were collected. The microorganisms were identified by traditional biochemical tests and genotypic methods, that is, PCR, internal transcript spacer PCR (ITS-PCR) and gene sequencing. Staphylococcal species were isolated in 18% (23/131) of the horses, of which 8% (11/131) were S. hyicus, 4% (5/131) were S. aureus, 4% (5/131) were S. pseudintermedius, and 2% (2/131) were S. schleiferi subsp. coagulans. The mecA gene was detected in an S. pseudintermedius isolate. Staphylococcus spp. was isolated in 40% (14/35) of the human samples, all of which were S. aureus. In four samples of S. aureus, the clonal profile ST398 was identified; among them, a clonal similarity of 98.1% was observed between a horse and a contacting human. This finding supports the need for biosecurity measures to avoid the spread of multidrug-resistant staphylococci in humans and horses. This review article by Kajsa Gustafsson and co-workers in Italy, Australia and Belgium investigated whether trimethoprim-sulfonamide is a valid antimicrobial treatment in foals. Trimethoprim-sulfonamide (TMPS) combinations are widely used to treat a range of infectious diseases in horses, but some equine practitioners are reluctant to use them for treatment of both neonatal and older foals. Considering the emergence of increased antimicrobial resistance, the use of protected antimicrobials commonly prescribed to foals should be avoided and alternative first-line therapy considered, where appropriate. The characteristics and pharmacokinetics of TMPS and its suitability for treatment of foals were examined in this study. Data regarding dosage and route of administration are reported based on recent publications in foals. This review shares significant information about the common infections that are most likely responsive to TMPS treatment in foals and, as such, where TMPS might be considered a suitable first-line therapeutic option. This study by Kari Means and co-workers in the United States aimed to determine associations between vertical pelvic movement asymmetry and location of primary lameness in ipsilateral combined forelimb and hindlimb lameness cases where hindlimb lameness is solely impact or push-off type. Cases with a consistent, low-variability ipsilateral impact or ipsilateral push-off hindlimb lameness in a straight-line trot and that had definitive diagnoses were identified from a body-mounted inertial sensor-evaluated equine lameness database. Cases were categorised by lameness location to the limb(s), diagnosis and the ratio of the amplitude of forelimb to hindlimb lameness (Forea/Hinda). Differences in the numbers of ipsilateral impact and ipsilateral push-off cases in these categories were analysed with chi-square tests, effect sizes and odds ratios. In total, 49 ipsilateral impact and 36 ipsilateral push-off cases met the criteria for consistency, low variability and definitive diagnosis. Ipsilateral impact cases were more likely than ipsilateral push-off cases to have forelimb-only lameness causes when Forea/Hinda was >1 (OR = 43, 95% CI = 2.3–798). Ipsilateral push-off cases were more likely than ipsilateral impact cases to have hindlimb-only causes when Forea/Hinda was >1.0 (OR = 20, 95% CI = 2.2–200) and < 1.0 (OR = 14, 95% CI = 2.9–66.7). Compared with ipsilateral impact, ipsilateral push-off cases were more frequently diagnosed with tendon, suspensory ligament or high-motion joint disorders in hindlimbs (OR = 3.6, 95% CI = 1.1–12.3) and less with unknown causes (OR = 13.2, 95% CI = 3.2–75.2). In ipsilateral impact cases, positive forelimb regional anaesthesia often reduced hindlimb lameness, whereas in ipsilateral push-off cases, positive hindlimb regional anaesthesia typically lessened forelimb lameness. This study by Rafael Françoso and co-workers in Brazil evaluated the feasibility of using the FreeStyle Libre (a continuous glucose monitoring system [CGMS]) for instantaneous continuous monitoring of interstitial glucose in adult horses and examined the applicability and accuracy of this system in horses submitted to combined glucose-insulin test (CGIT). Ten healthy stallions were assigned to one of two groups based on their body condition scores (BCS). Group 1 (G1, n = 5) consisted of nonobese horses with a BCS of 5 or 6, while Group 2 (G2, n = 5) consisted of obese horses with a BCS of 7 or higher. A CGMS sensor was attached to the dorsolateral aspect of the proximal one third of each horse's neck. Laboratory blood glucose measurements and CGMS interstitial glucose readings were compared at different time points for up to 7 days after sensor fixation. Obese horses were also submitted to CGIT on Day 4. Laboratory measurements and CGMS readings were analysed using a 2 × 2 factorial statistical model with repeated measures over time. This analysis assessed the effects of the test (factor 1), group (factor 2) and their interactions (test × group, test × time, and group × time). Pearson's correlation analysis was applied to blood glucose values. Mean comparisons were conducted using the t-test, and agreement between techniques was assessed via the Bland–Altman method, with a 95% confidence interval. A comparative analysis of glucose measurements obtained in G1 and G2 horses using the CGMS, and enzymatic methods revealed significant group × time interactions (p < 0.001) and time effects (p < 0.001). No interactions were detected between group (p = 0.45), test (p = 0.62), group and test (p = 0.28) or time and test (p = 0.92). In G1 and G2, tests were significantly correlated (r = 0.84 and p = 0.00) at all time points (T0–T5). Agreement between the glucose values obtained using different methods was excellent despite a small time delay in CGMS detection of rapid changes in blood glucose. The authors concluded that the CGMS can be used for indirect assessment of glycaemic status (i.e. based on interstitial glucose measurements) in nonobese and obese adult horses submitted to CGIT.