Luis Pardon Lamas

The ocular surface represents a unique microbial ecosystem continuously exposed to environmental microorganisms; however, the fungal component of the healthy equine ocular microbiome remains poorly characterized. This study aimed to characterize the ocular surface mycobiome of 12 clinically healthy Purebred Lusitano horses from three geographical regions in Portugal kept in two housing systems using Oxford Nanopore long-read sequencing and conventional fungal culture. Sequencing revealed a highly diverse fungal community with marked inter-individual variability. The most abundant genera were Wallemia, Podosphaera, Debaromyces, Aspergillus, Filobasidium, Kurtzmaniella, Metschnikowia, Malassezia and Spathaspora. Patterns of fungal community composition suggested that local environmental conditions may contribute to the observed inter-individual variability. Genera commonly associated with equine fungal keratitis, including Aspergillus, Fusarium and Penicillium, were detected in healthy horses irrespective of housing system. Overall, the healthy equine ocular surface was characterized by a diverse mycobiome dominated by environmentally associated fungi. There findings provide a baseline for future studies investigating ocular microbial dysbiosis, environmental determinants of fungal community structure, and equine ocular health.

Summary: Objectives: To evaluate the effectiveness of a two‐step hoof sterilisation protocol consisting of povidone–iodine (PI) scrub followed by dry heat application in reducing bacterial contamination in equine hooves. Study design: Ex vivo experimental study with limited clinical application. Sample population: Nine cadaveric equine limbs and description of five clinical cases. Methods: Hooves were frozen, thawed, rehydrated and recontaminated with faecal material to mimic in vivo clinical conditions. Core tissue samples were collected from the dorsal hoof wall (DHW), sole (SOL) and frog (FRG) at three timepoints: after recontamination (T0), after a 6‐min PI preparation (T1) and after 4‐min dry heat application at 200°C (T2). The effect of heat alone was evaluated in three additional limbs. Internal tissue temperature was monitored during heat application. Bacterial loads were quantified as log ₁₀ CFU/g. Statistical analyses included Friedman tests and Wilcoxon signed‐rank tests with Bonferroni correction. Results: Bacterial counts decreased by 94.4% between T0 and T1 ( p < 0.001), 98.0% between T1 and T2 (p < 0.001), and by 99.9% between T0 and T2 ( p < 0.00001). Heat alone produced reductions of 98–99%; in the sole and frog responses were more variable. Internal tissue temperatures remained within physiological limits throughout the procedure. The two‐step protocol was applied in five clinical cases without complications or surgical site infections. Main limitations: Ex vivo study design and limited clinical case numbers. Conclusion: The sequential application of PI scrub and a controlled dry heat protocol substantially reduced bacterial contamination across all regions of this surgical site model while the temperature of live tissues remained within a physiological range.

The diagnosis of gastrointestinal (GI) strongyle infections in equids is still mainly performed using quantitative coprological techniques, like the McMaster (McM), but more sensitive and precise techniques, like FLOTAC (FL) and Mini-FLOTAC (MF), have been proposed over the past 20 years. The present study aimed to compare the analytical performance of these three methods in the diagnosis of strongyle infections in horses. Between October 2023 and June 2024, 32 fecal samples were processed using the McM, FL and MF techniques to identify strongyles’ eggs, estimate their shedding (eggs per gram of feces, EPG), standard errors, sensitivities, precisions, and perform Spearman’s correlation and Cohen’s kappa analyses. The McM detected a higher shedding (584 ± 179 EPG), in comparison with FL and MF, with both these differences being statistically significant (p < 0.001); FL achieved the highest precision (72%), which differed significantly from McM (p = 0.03). All techniques were positively (r_s = 0.92–0.96) and significantly (p < 0.001) correlated and shared substantial (k = 0.67–0.76) and significant (p < 0.001) agreement. The MF achieved the highest diagnostic sensitivity (93%), followed by FL (89%) and McM (85%), although not significantly (p = 0.90). These results suggest the usefulness of implementing FL or MF methods in equine medicine for precise and, in the latter case, quick parasitological diagnosis.

Summary: Background: Established or ongoing septic arthritis requiring repeated joint flushing remains a treatment challenge with a poor survival outcome aggravated by the necessity of controlled antimicrobial usage. Objective: To describe the outcomes and survival rates of patients with synovial sepsis treated by lavage with a 0.05% chlorhexidine solution. Study design: Clinical retrospective observational study. Methods: Patients with synovial sepsis underwent standing needle or arthroscopic lavage under general anaesthesia with a 0.05% chlorhexidine solution, followed by Lactate Ringer Solution (LRS). Complementary systemic and regional antibiotics were used. Short‐ (6 months) and long‐term (>1 year) outcomes were assessed. Results: Ten horses met the inclusion criteria. Affected joints included metacarpophalangeal joints (2), tarsocrural joint (1), radiocarpal and intercarpal joints (2), distal interphalangeal joints and navicular bursa (3), distal interphalangeal joints (2). Time from onset to referral ranged from 1 to 20 days, with a mean of 8.3 days. Eighty per cent of horses survived for more than 1 year. Four horses were retired to the field, three returned to a light level of work and one went back to full work. Main limitations: Retrospective study of a limited group of horses initially treated by different clinicians before referral, as such, first‐line treatment had differences between cases. Resolution was evaluated on based clinical signs rather than clinical pathology of synovial fluid due to clinical decisions or difficulty in obtaining samples. Conclusion: With this series of challenging synovial sepsis cases treated by lavage with a chlorhexidine solution, we provide a treatment protocol, proof of clinical concept and report patients' short‐ and long‐term clinical outcomes. Short‐ and long‐term postoperative lameness should be expected despite the resolution of the septic arthritis. This treatment poses a novel option for challenging cases but should be regarded as a salvage procedure due to the possibility of long‐term mild lameness.

Terrestrial animals not only need to walk and run but also lie prone to rest and then stand up. Sit-to-stand (STS) and sit-to-walk (STW) transitions are vital behaviours little studied in species other than humans so far, but likely impose biomechanical constraints on limb design because they involve near-maximal excursions of limb joints that should require large length changes and force production from muscles. By integrating data from experiments into musculoskeletal simulations, we analysed joint motions, ground reaction forces, and muscle dynamics during STS and STW in a large terrestrial, bipedal and cursorial bird: the emu (Dromaius novaehollandiae; body mass ∼30 kg). Simulation results suggest that in both STS and STW, emus operate near the functional limits (∼50% of shortening/lengthening) of some of their hindlimb muscles, particularly in distal muscles with limited capacity for length change and leverage. Both movements involved high muscle activations (>50%) and force generation of the major joint extensor muscles early in the transition. STW required larger net joint moments and non-sagittal motions than STS, entailing greater demands for muscle capacity. Whilst our study involves multiple assumptions, our findings lay the groundwork for future studies to understand, for example, how tendon contributions may reduce excessive muscle demands, especially in the distal hindlimb. As the first investigation into how an avian species stands up, this study provides a foundational framework for future comparative studies investigating organismal morphofunctional specialisations and evolution, offering potential robotics and animal welfare applications.

Animals not only need to walk and run but also lie prone to rest and then stand up. Sit-to-stand (STS) and sit-to-walk (STW) transitions are vital behaviours little studied in species other than humans so far, but likely impose biomechanical constraints on limb design because they involve near-maximal excursions of limb joints that should require large length changes and force production from muscles. By integrating data from experiments into musculoskeletal simulations, we analysed joint motions, ground reaction forces, and muscle dynamics during the STS and STW transitions in a large terrestrial, bipedal, and cursorial bird: the emu (Dromaius novaehollandiae, ∼ 30 kg). Simulation results suggest that in both STS and STW, emus operate near the functional limits (∼ 50 % of shortening/lengthening) of some of their hindlimb muscles, particularly in distal muscles with limited capacity for length change and leverage. Both movements involved high muscle activations (> 50 %) and force generation of major joint extensor muscles early in the transition. STW also required larger net joint moments and non-sagittal motions, entailing greater demands for muscle capacity. Whilst our study involves multiple assumptions, our findings lay the groundwork for future studies to understand, for example, how tendon contributions may reduce excessive muscle demands, especially in the distal hindlimb. As the first investigation into how an avian species stands up, this study provides a foundational framework for future comparative studies investigating organismal morphofunctional specialisations and evolution, offering potential robotics and animal welfare applications. Summary statement The study demonstrates the dynamics, biomechanical constraints, and musculotendinous control strategies during the sit-to-stand/walk transitions for a large bipedal bird – the emu – informing morphology, evolution, and potential robotic applications.

The objective of this study was to describe prolonged surgical anaesthesia and recovery in fire salamanders ( Salamandra salamandra) using tricaine methanesulfonate (MS-222). A total of 14 salamanders were anaesthetised for electromyography wire implantation. Sodium bicarbonate buffered solutions (0.5–4 g l^–1) of MS-222 were prepared (adjusted to pH 7.0). Anaesthesia was induced by partial immersion in pre-oxygenated 3 g l^–1 solution for 20 min. Buprenorphine (0.5 mg kg^–1) was administered subcutaneously. During microsurgery, heart rate (HR), solution pH and temperature were recorded. Reflectance pulse oximeter (SpO2) (Masimo Rad-57) was recorded in two salamanders. Anaesthetic plane and MS-222 pH stability (pH 7.6) were maintained by renewing administration of oxygenated MS-222 solution (0.5–3 g l^–1) onto swabs that partially covered the body. Recovery started at the end of surgery (MS-222 0 g l^–1). Postoperatively, salamanders were given oral meloxicam (0.2 mg kg^–1). Mean time for loss of righting reflex during induction was 13.7 ± 2.2 min. Duration of anaesthesia and time to recovery were 111 ± 24.2 and 31 ± 10.3 min, respectively. Due to complications, two salamanders did not recover. Baseline HR was 67.4 ± 34.5 beats/min, and it decreased significantly until recovery ( p ≤ 0.0001). In two salamanders, baseline SpO2 was 85.5% ± 14.5, SpO2 during surgery was 61% ± 6.4, improving to 80.5% ± 2.1 on recovery. In conclusion, prolonged recovery anaesthesia is achievable with MS-222 dilutions in salamander. Reflectance SpO2 could prove valuable during immersion anaesthesia.

Meloxicam is a widely used nonsteroidal anti‐inflammatory drug in avian species. However, variability in pharmacokinetic (PK) and pharmacodynamic (PD) parameters in birds warrants species‐specific studies for dose and dosing interval optimization. We performed a perioperative PK study of meloxicam (0.5 mg/kg, intravenously) on emus of three different age groups: 3 chicks (5 weeks old, 3.5 kg), 4 juveniles (26 weeks old, 18.8 kg) and 6 adults (66 weeks old, 38.8 kg). A two‐compartment population PK model including weight as a significant covariate on clearance and central volume of distribution (V1) best fitted the data. The typical values (20 kg bird) for clearance and V1 were 0.54 L/kg/h and 0.095 L/kg. Both parameters significantly decreased with increasing weight/age. Meloxicam potency and selectivity for COX‐1 and COX‐2 were measured in whole blood assays (TxB₂ production endpoint). Meloxicam was partially selective in emus (IC₅₀ COX‐1:COX‐2 = 9.1:1). At the current empirical dose (0.5 mg/kg/24 hr), plasma meloxicam concentration is above IC₅₀ of COX‐2 for only 2 hr. PK/PD predicted dose required for 80% COX‐2 inhibition over 24 hr were 3.4, 1.4 and 0.95 L/kg/day in chicks, juveniles and adult emus, respectively. The safety, therapeutic efficacy and practicality of modifying the daily dose or dose interval should be considered for dose recommendations in emus.

The objective of this study was to identify the prognostic value for survival of blood parameters in the immediate post-caesarean surgery period in kids born from pregnancy toxaemia (PT) goats. This study involved 10 PT goats, in which a caesarean surgery was performed. Twenty-five kids were born after caesarean surgery of which 16 survived. A blood sample was collected from the jugular vein of the 10 goats and from the kids immediately after caesarean surgery (within 15 min). There were differences between the kids that survived and the kids that did not survive concerning the blood levels of pH (7.22 vs 7.00), base excess (− 9 vs − 18 mmol/L), pCO₂(46 vs 62 mmHg) and L-lactate (5.6 vs 16 mmol/L). Maternal ketoacidosis due to PT has a negative impact on the survival rate of the offspring. This appears to be associated to a metabolic acidosis of the offspring. However, the only blood parameter in which there was a strong association between the maternal and newborn kids was blood urea nitrogen (r = 0.97).

Colic is a serious disease for horses and the nutritional management of postoperative colic patients is an extremely important field. The aim of this retrospective study was to analyse the different factors, especially related to nutritional management, that may be associated with recovery length during hospitalization after a surgical intervention for colic, using a multivariate model. Data were collected from the records of horses presented to two hospitals and undergoing surgery for colic. The length (days) of recovery was the outcome of interest and was taken into account as a reference parameter (short, medium, long). The parameters collected (patient details, preoperative clinical and laboratory examinations, postoperative parameters and post‐surgery nutritional parameters) were subjected to multivariate analysis (MCA and PCoA). A ranking class dataset was used to calculate Kendall's tau correlation of the length of recovery with respect to other parameters. Descriptive statistic to identify differences in the recovery length among groups (Kruskal–Wallis and Dunn's Multiple Comparison Test) was also performed. p value was set at < 0.05. Groups were not different in preoperative clinical parameters (BCS, PCV, total protein), postoperative parameters (time to 1st defecation, time to the end of IV fluid therapy and time to first water drinking, anaesthesia) and patient details (age). The comparison among groups revealed differences on the post‐surgical nutritional parameters. Horses with short recovery consumed higher % of DM as forages in the 24 hr compared with the horses that have a long recovery and reach the minimum DM intake in a shorter period. Both Kendall and MCA analysis confirmed that the time to first feeding had a positive association with the length of recovery. Only 37 horses undergoing colic surgery were included in the study. From a clinical standpoint, this study has shown which nutritional parameters are associated with short recovery.