Flowmetry and spectrophotometry can detect reduced intestinal microperfusion in nonsurvivors during equine colic surgery for large intestinal strangulation.

OBJECTIVE: To evaluate the use of laser Doppler flowmetry and spectrophotometry (LDFS) for large intestinal viability assessment in horses with naturally occurring large intestinal strangulations. METHODS: By use of LDFS, intestinal microperfusion was quantified as tissue oxygen saturation (tSo2), hemoglobin (tHB), and blood flow (tBF) in cases with large colon volvulus and small colon strangulations undergoing colic surgery (n = 17). Intestinal biopsies were taken from the pelvic flexure in all large colon cases and in small colon cases that underwent intraoperative euthanasia. Measurements were compared between survivors and nonsurvivors, and the correlation between LDFS and (immuno)histology was tested (P < .05). RESULTS: The tSo2 and tBF were clearly lower and tHB was higher than previously reported in healthy horses. Following correction of the lesion, pelvic flexure tBF was significantly lower than that of the left ventral colon. Prior to correction of the lesion, microperfusion did not differ between survivors and nonsurvivors, but following release of the strangulation the survivors had a significantly higher tSo2 and tBF compared to the nonsurvivors. There was a negative correlation between tBF and interstitium-to-crypt ratio and a positive correlation between tHB and the histological hemorrhage score. There were no significant correlations between LDFS measurements and inflammatory cell counts or hypoxia-inducible factor-1α immunoreactivity. CONCLUSIONS: Large intestinal microperfusion was decreased in nonsurvivors compared to survivors and was correlated with histological injury, suggesting that LDFS has the potential to predict tissue injury and postoperative survival. CLINICAL RELEVANCE: The use of LDFS as an ancillary diagnostic aid may improve intraoperative viability assessment during colic surgery.

Storage of equine faecal microbiota transplantation solution has minimal impact on major bacterial communities and structure.

Management of diarrhoea in horses is usually non-specific and supportive. Faecal microbiota transplantations (FMT) are used to manage dysbiosis in horses with diarrhoea. There are few studies investigating the effects of storage on prepared FMT solutions. This study was an in vitro non-randomised controlled experiment that investigated the effects of FMT solution preparation and storage on the faecal microbiota. Fresh faeces were collected from five healthy adult horses and used for DNA extraction and preparation of FMT. From each FMT, seven aliquots were collected and DNA was extracted immediately after FMT preparation (0hr), after storage at 4oC for 24, 48 or 72hours, and after storage at -20°C for 7 days, 14 days or 28 days. The extracted DNA was used for 16S rRNA gene sequencing. The relative abundance, alpha diversity and beta diversity between fresh faeces and FMT 0hr showed no differences (P ≥ 0.05). There were minimal changes in the microbiota of FMT stored at 4°C for up to 72hours and -20°C for up to 28 days. The results of this study indicate that preparation of equine FMT solution has minimal effect on the microbiota in comparison to fresh faeces. FMT solution can be stored at 4°C for up to 3 days and -20°C for 28 days without major change in microbiota.

In vivo comparative study of hemp straw exposure and cannabidiol oil administration in horse urine.

The non-psychoactive cannabinoids cannabidiol (CBD) and cannabidiolic acid (CBDA) are available on the market in different forms, mostly for their anti-inflammatory and potential analgesic properties. These substances are prohibited during equine competitions. CBD and CBDA are naturally present in hemp straw, commonly used as a bedding substitute for wheat straw. Unfortunately, horses can eat it, which therefore could lead to a possible risk of positive findings for CBD/CBDA in biological samples after doping control tests. The goals of this study were, first, to provide recommendations on the use of hemp straw before competition and, second, to assess if discrimination between hemp bedding exposure and CBD oil administration is possible. Several CBD equine in vivo studies have been conducted, including one on hemp straw used as bedding and one after administration of CBD oil by topical and sublingual routes. In hemp straw, CBDA was detected in higher quantities than CBD, and other cannabinoids have been observed. After hemp straw exposure, CBDA was also detected in higher quantities than CBD in all urine samples. It appeared that hemp straw should not be used as bedding for equine competition except if a delay of at least 48 h is respected. Regarding the CBD oil product analysis, CBD was the main compound detected. After administration, 7-hydroxy CBD was identified in the urine. In conclusion, based on these data, we highlighted that it could be possible to discriminate the exposure of a horse to hemp straw from an administration of a CBD oil product thanks to the main presence of CBDA.

Evaluation of variants in the ENTPD1 and ENTPD2 genes in athletic horses with exercise-induced pulmonary haemorrhage.

BACKGROUND: Exercise-induced pulmonary haemorrhage (EIPH) in athletic horses is characterized by the presence of blood from the lungs in the tracheobronchial tree after intense exercise. Despite the high prevalence of EIPH in horses, the primary aetiology remains unknown. Variants in the genes encoding CD39 and CD39L1 (ENTPD1 and ENTPD2, respectively) were previously reported as potential genetic causes involved in EIPH pathogenesis. However, the role of these variants in haemostatic functions is unknown. RESULTS: To investigate the association between EIPH and missense variants in the ENTPD1 (rs1152296272, rs68621348, and rs68621347) and ENTPD2 genes (rs782872967), 76 Thoroughbred horses diagnosed with EIPH and 56 without clinical signs of EIPH (control group) by trachea-bronchial endoscopy were genotyped. The rs1152296272 and rs68621347 variants were linked, which explained why the same results were found in all horses. Approximately 96% and 95% of the EIPH and control horses, respectively, carried at least one nonreference allele for these variants. In contrast, 100% of the control horses and 96% of the EIPH horses were homozygous for the reference allele for the rs68621348 variant. In the EIPH group, 1.5% of the horses were homozygotes and 24% were heterozygous for the nonreference allele of the rs782872967 variant. In the control group, the nonreference allele of this variant was observed only in heterozygotes (16%). There were no significant differences between groups for any of the variants. CONCLUSIONS: The variants previously described in the genes encoding the CD39 and CD39L1 enzymes were highly present in the studied population. However, no association was found between the occurrence of EIPH and the presence of these variants in Thoroughbred horses in this study.

Culture and Immunomodulation of Equine Muscle-Derived Mesenchymal Stromal Cells: A Comparative Study of Innovative 2D versus 3D Models Using Equine Platelet Lysate.

Muscle-derived mesenchymal stromal cells (mdMSCs) hold great promise in regenerative medicine due to their immunomodulatory properties, multipotent differentiation capacity and ease of collection. However, traditional in vitro expansion methods use fetal bovine serum (FBS) and have numerous limitations including ethical concerns, batch-to-batch variability, immunogenicity, xenogenic contamination and regulatory compliance issues. This study investigates the use of 10% equine platelet lysate (ePL) obtained by plasmapheresis as a substitute for FBS in the culture of mdMSCs in innovative 2D and 3D models. Using muscle microbiopsies as the primary cell source in both models showed promising results. Initial investigations indicated that small variations in heparin concentration in 2D cultures strongly influenced medium coagulation with an optimal proliferation observed at final heparin concentrations of 1.44 IU/mL. The two novel models investigated showed that expansion of mdMSCs is achievable. At the end of expansion, the 3D model revealed a higher total number of cells harvested (64.60 ± 5.32 million) compared to the 2D culture (57.20 ± 7.66 million). Trilineage differentiation assays confirmed the multipotency (osteoblasts, chondroblasts and adipocytes) of the mdMSCs generated in both models with no significant difference observed. Immunophenotyping confirmed the expression of the mesenchymal stem cell (MSC) markers CD-90 and CD-44, with low expression of CD-45 and MHCII markers for mdMSCs derived from the two models. The generated mdMSCs also had great immunomodulatory properties. Specific immunological extraction followed by enzymatic detection (SIEFED) analysis demonstrated that mdMSCs from both models inhibited myeloperoxidase (MPO) activity in a strong dose-dependent manner. Moreover, they were also able to reduce reactive oxygen species (ROS) activity, with mdMSCs from the 3D model showing significantly higher dose-dependent inhibition compared to the 2D model. These results highlighted for the first time the feasibility and efficacy of using 10% ePL for mdMSC expansion in novel 2D and 3D approaches and also that mdMSCs have strong immunomodulatory properties that can be exploited to advance the field of regenerative medicine and cell therapy instead of using FBS with all its drawbacks.

"How long is life worth living for the horse?" A focus group study on how Austrian equine stakeholders assess quality of life for chronically ill or old horses.

BACKGROUND: Quality of life (QoL) provides a comprehensive concept underpinning veterinary decision-making that encompasses factors beyond physical health. It becomes particularly pertinent when seeking responsible choices for chronically ill or old horses that emphasise their well-being and a good QoL over the extension of life. How different stakeholders use the concept of QoL is highly relevant when considering the complexity of these decisions in real-life situations. METHODS: Seven focus group discussions (N = 39) were conducted to gain insights into how stakeholders assess and use equine QoL in veterinary care decisions for chronically ill and/or old horses. The discussions included horse owners (n = 17), equine veterinarians (n = 7), veterinary officers (n = 6), farriers (n = 4), and horse caregivers (n = 5). The combination of deductive and inductive qualitative content analysis of the group discussions focused on identifying both similarities and differences in the views of these groups regarding QoL for old and/or chronically ill horses. RESULTS: Findings show agreement about two issues: the importance of the individuality of the horse for assessing QoL and the relevance of QoL in making decisions about veterinary interventions. We identified differences between the groups with respect to three issues: the time required to assess QoL, stakeholders' contributions to QoL assessments, and challenges resulting from those contributions. While owners and caregivers of horses emphasised their knowledge of a horse and the relevance of the time they spend with their horse, the veterinarians in the study focused on the differences between their own QoL assessments and those of horse owners. In response to challenges regarding QoL assessments and decision-making, stakeholders described different strategies such as drawing comparisons to human experiences. CONCLUSIONS: Differences between stakeholders regarding equine QoL assessments contribute to challenges when making decisions about the care of chronically ill or old horses. The results of this study suggest that individual and collaborative reflection about a horse's QoL should be encouraged, for example by developing practicable QoL assessment tools that support relevant stakeholders in this process.

Review of Pseudomonas aeruginosa and Klebsiella pneumoniae as venereal pathogens in horses.

Three bacteria extensively acknowledged as venereal pathogens with the potential to induce endometritis include Taylorella equigenitalis, the causative agent of contagious equine metritis (CEM), specific strains of Pseudomonas aeruginosa, and certain capsule types of Klebsiella pneumoniae. The United Kingdom's Horserace Betting Levy Board recommends pre-breeding screening for these bacteria in their International Codes of Practice and >20 000 samples are tested per annum in the United Kingdom alone. While the pathogenesis and regulatory importance of CEM are well established, an evaluation of the literature pertaining to venereal transmission of P. aeruginosa and K. pneumoniae was lacking. The aim of this review was to evaluate published literature and determine the significance of P. aeruginosa and K. pneumoniae as venereal pathogens in horses. Literature definitively demonstrating venereal transmission was not available. Instead, application of molecular typing methods suggested that common environmental sources of contamination, such as water, or fomites be considered as modes of transmission. The presence of organisms with pathogenic potential on a horse's external genitalia did not predict venereal transmission with resultant endometritis and reduced fertility. These findings may prompt further investigation using molecular technologies to confirm or exclude venereal spread and investigation of alternative mechanisms of transmission are indicated.

Return to sport activity following ultrasonographic diagnosis and conservative management of spontaneous injuries of the serratus cervicis ventralis and serratus thoracis ventralis muscles in 11 endurance horses.

OBJECTIVE: To describe the clinical diagnosis, ultrasound findings, and outcome of 11 endurance horses with injuries to the serratus ventralis thoracis (SVT) or serratus ventralis cervicis (SVC) muscle. ANIMALS: 11 endurance horses competing in medium- to high-level competitions and presenting with lameness caused by injuries to the SVT or SVC muscle, as confirmed by ultrasonography. CLINICAL PRESENTATION: Physical examinations revealed swelling caudal to the shoulder region associated with dorsocranial displacement of the scapula and edema of the ventral thorax for horses with SVT injuries. Swelling cranial to the scapula and edema of the pectoral area were identified among horses with injuries to the SVC. RESULTS: Dynamic examinations revealed moderate-to-severe reduction of the cranial phase of the stride at the walk; at the trot, a lameness score of 2 to 3/5 was assigned (modified American Association of Equine Practitioners Lameness Scale). Ultrasonography revealed moderate-to-severe increases in size of the muscle body, heterogeneous echogenicity, loss of the striated muscle pattern, and varying degrees of perimuscular edema. All horses were able to resume full training and competition in an average of 216 days (range, 74 to 362 days) and 148 days (range, 112 to 309 days) for injuries of the SVT and SVC, respectively. CLINICAL RELEVANCE: This case series is the first to describe the clinical and ultrasonographic features of spontaneous injuries to the SVT or SVC. Ultrasonography for diagnosis was simple and well tolerated by the horses.

Segmentation of ovarian cyst in ultrasound images using AdaResU-net with optimization algorithm and deep learning model.

Ovarian cysts pose significant health risks including torsion, infertility, and cancer, necessitating rapid and accurate diagnosis. Ultrasonography is commonly employed for screening, yet its effectiveness is hindered by challenges like weak contrast, speckle noise, and hazy boundaries in images. This study proposes an adaptive deep learning-based segmentation technique using a database of ovarian ultrasound cyst images. A Guided Trilateral Filter (GTF) is applied for noise reduction in pre-processing. Segmentation utilizes an Adaptive Convolutional Neural Network (AdaResU-net) for precise cyst size identification and benign/malignant classification, optimized via the Wild Horse Optimization (WHO) algorithm. Objective functions Dice Loss Coefficient and Weighted Cross-Entropy are optimized to enhance segmentation accuracy. Classification of cyst types is performed using a Pyramidal Dilated Convolutional (PDC) network. The method achieves a segmentation accuracy of 98.87%, surpassing existing techniques, thereby promising improved diagnostic accuracy and patient care outcomes.

Peri-anaesthetic complications in 1798 equids undergoing high-field elective orthopaedic MRI at a tertiary referral hospital.

BACKGROUND: Antimicrobial prophylaxis for elective orthopaedic magnetic resonance imaging (MRI) in equids is a topic of debate among practitioners and can have negative detrimental effects on patients if used unnecessarily. OBJECTIVES: To describe the complications with elective orthopaedic MRI of horses, mules, and donkeys under general anaesthesia without the use of peri-anaesthetic antimicrobial prophylaxis at a single large tertiary referral centre. We hypothesised that horses, mules, and donkeys undergoing general anaesthesia for elective orthopaedic MRI, without antimicrobial prophylaxis, will not be at increased risk of complications, including increased risk of infectious respiratory disease. STUDY DESIGN: Retrospective cross-sectional study. METHODS: This retrospective study of 1798 systemically healthy equids that underwent elective orthopaedic MRI under general anaesthesia without peri-anaesthetic antimicrobial prophylaxis between January 2009 and May 2020. RESULTS: A total of 1655 MRIs were included in the study, with 25 (1.5%) horses having complications. The most common complication was post-anaesthetic fever in 11 (0.7%) horses, of which 4 (0.2%) horses went on to develop pneumonia and one horse was diagnosed with equine herpesvirus (respiratory). Seven (0.4%) horses developed transient post-anaesthetic femoral neuropathy and 7 (0.4%) horses had mild post-anaesthetic colic that resolved with initial medical management. No horses were euthanised or died in this study. MAIN LIMITATIONS: The retrospective nature of the study led to non-randomised case selection, and some records were incomplete. CONCLUSIONS: These findings suggest that peri-anaesthetic antimicrobial prophylaxis may not be necessary for performance and sport horses undergoing general anaesthesia for elective orthopaedic MRI.

Comparison of radiography and computed tomography for identification of third metacarpal structural change and associated assessment of condylar stress fracture risk in Thoroughbred racehorses.

BACKGROUND: Catastrophic injury has a low incidence but leads to the death of many Thoroughbred racehorses. OBJECTIVES: To determine sensitivity, specificity, and reliability for third metacarpal condylar stress fracture risk assessment from digital radiographs (DR) and standing computed tomography (sCT). STUDY DESIGN: Controlled ex vivo experiment. METHODS: A blinded set of metacarpophalangeal joint DR and sCT images were prepared from 31 Thoroughbreds. Four observers evaluated the condyles and parasagittal grooves (PSG) of the third metacarpal bone for the extent of dense bone and lucency/fissure and assigned a risk assessment grade for condylar stress fracture based on imaging features. Sensitivity and specificity for detection of subchondral structural changes in the condyles and PSG, and for risk assessment for condylar stress fracture were determined by comparison with a reference assessment based on sCT and joint surface examination. Agreement between observers and the reference assessment and reliability between observers were determined. Intra-observer repeatability was also assessed. RESULTS: Sensitivity for detection of structural change was lower than specificity for both imaging methods and all observers. For agreement with the reference assessment of structural change, correlation coefficients were generally below 0.5 for DR and 0.49-0.82 for sCT. For horses categorised as normal risk on reference assessment, observer assessment often agreed with the reference. Sensitivity for risk assessment was lower than specificity for all observers. For horses with a reference assessment of high risk of injury, observers generally underestimated risk. Diagnostic sensitivity of risk assessment was improved with sCT imaging, particularly for horses categorised as having elevated risk of injury from the reference assessment. Assessment repeatability and reliability was better with sCT than DR. MAIN LIMITATIONS: The ex vivo study design influenced DR image sets. CONCLUSIONS: Risk assessment through screening with diagnostic imaging is a promising approach to improve injury prevention in racing Thoroughbreds. Knowledge of sensitivity and specificity of fetlock lesion detection provides the critical guidance needed to improve racehorse screening programs. We found improved detection of MC3 subchondral structural change and risk assessment for condylar stress fracture with sCT ex vivo.

Biodiversity and probiotic potential of yeasts isolated from sumbawa horse milk.

BACKGROUND: The microbial composition of Sumbawa Horse Milk is influenced by various factors, including environmental elements that encompass geographical location, climate, and conditions specific to Sumbawa. This study aimed to determine the biodiversity and genetic diversity of the microbiome of Sumbawa Horse Milk, with an emphasis on yeast. METHODS: The diversity and group of yeast isolates were evaluated by the sequence-related amplified polymorphism (SRAP) method using ME2F-EM15R (1) and ME2F-EM12R (2) primers. Molecular identification using 18 S rRNA primers was then carried out on nine selected isolates (K_21, K_31, K_42, K_45, K_1, K_6, K_8, K_17, and K_19) to determine the type of yeast. Probiotic candidate tests were carried out on three isolates, namely K_1, K_6 and K_8. RESULTS: Analysis with NTSYS software on the SRAP results using Primer 1 revealed the presence of two major groups, where Group I was exclusively comprised of K_45 isolate, whereas the other isolates belonged to Group II. On the other hand, analysis with NTSYS software on the SRAP analysis with Primer 2 also showed two major groups with different compositions. Group I consisted of isolates K_39, 38, 37, 36, 35, 34, 33, 31, 29, 28, 27, 26, 25, 24, 23, 22, and 21, while the remaining isolates belonged to Group II. Results of 18 S rRNA analysis demonstrated that K_17 and K_19 had 99.8 and 100% similarity, respectively, and identified as Candida humilis. K_21, K_31, and K_45 were identified as having a 100% similarity to Clavispora lusitaniae, while K_42 had a 99.8% similarity to Candida parapsilosis. Three isolates were identified as belonging to the genus Ogataea, namely Ogataea polymorpha (K_6 and K_8) and Ogataea siamensis (K_1) with similarity of 100% and 99.8%, respectively. CONCLUSIONS: These findings suggest that the three yeast have potential as probiotics.

Assessment of fetal development during mid and late term pregnancies by standard B-Mode ultrasonography in Shetland ponies.

Transrectal and transabdominal ultrasonography is an established method to monitor pregnancy, fetal growth and wellbeing in different species. Growth charts with multiple bio-morphometric parameters to estimate days of gestation and days before parturition exist in small companion animals, sheep and goats, riding type horses and large ponies but not in small horse breeds like Shetland ponies. The aim of this study was to apply fetal biometric assessment and detailed description of physiologic fetal development to mid and late term pregnancies in Shetland mares and to generate reference data for clinical practice and for future research. Fetal parameters were collected starting on day 101 of pregnancy in five Shetland mares. The fetal biometric parameters determined consisted of aortic diameter, eye diameter, combined rib and intercostal distance (CRID), stomach length and width and different heart morphology parameters in sagittal and frontal plane. Additionally, fetal activity and organ development in terms of differentiation and changes in echogenicity were recorded. Considering reliably assessable parameters, fetal CRID was the best predictor for gestational age with ± 13.6 days and fetal aortic diameter the most accurate for prediction of days until parturition with ± 16.2 days.

Retrospective study of the changes in dynamic compliance and ventilation/perfusion mismatch following salbutamol inhalation in hypoxaemic mechanically ventilated anaesthetized horses.

OBJECTIVE: To study the changes in dynamic compliance (Cdyn), ventilation/perfusion (V˙/ Q˙) mismatch and haemodynamic variables in hypoxaemic anaesthetized horses whose PaO2 increased following salbutamol inhalation. STUDY DESIGN: Retrospective, clinical, cohort study. ANIMALS: A group of 73 client-owned horses treated with salbutamol when PaO2 <100 mmHg (13.3 kPa) during anaesthesia. METHODS: Horses were divided into two groups: responders (R), where PaO2 after salbutamol ≥1.2 PaO2 before treatment (i.e. ≥20% increase), and non-responders (NR), where PaO2 after salbutamol <1.2 PaO2 before treatment. Demographic data and intraoperative variables before treatment were compared between R and NR. Cdyn, arterial to end-tidal carbon dioxide difference [P(a-E´)CO2], estimated ratio of dead space to tidal volume (est.VD/VT), estimated shunt fraction (F-shunt), heart rate, systolic, mean and diastolic arterial pressure and dobutamine requirements were compared before and after treatment within R and NR. For each variable, the difference (Δ) between values pre- and posttreatment was calculated and compared between groups R and NR. Numerical data were compared using univariate or bivariate analysis and categorical data were compared using chi-square test; p < 0.05. RESULTS: Of the 73 horses 50 were classified as R while 23 horses were classified as NR. There was no statistical difference between R and NR for demographic data or initial intraoperative variables except for body weight [R: 531 (170-715) kg, NR: 540 (420-914) kg]. While salbutamol did not alter Cdyn in either group, it significantly decreased P(a-E´)CO2, est.VD/VT and F-shunt in R only. ΔP(a-E´)CO2, Δest.VD/VT and ΔF-shunt were significantly greater in R (-17.8%, -19.0% and -24.1%, respectively) than in NR (11.5%, 6.6% and -0.3%, respectively). CONCLUSIONS AND CLINICAL RELEVANCE: In hypoxaemic anaesthetized horses responding to inhaled salbutamol by a ≥1.2 increase in PaO2 no change in Cdyn was detected, but indicators of V˙/ Q˙ mismatch improved.

In search of epigenetic hallmarks of different tissues: an integrative omics study of horse liver, lung, and heart.

DNA methylation and microRNA (miRNA) expression are epigenetic mechanisms essential for regulating tissue-specific gene expression and metabolic processes. However, high-resolution transcriptome, methylome, or miRNAome data is only available for a few model organisms and selected tissues. Up to date, only a few studies have reported on gene expression, DNA methylation, or miRNA expression in adult equine tissues at the genome-wide level. In the present study, we used RNA-Seq, miRNA-seq, and reduced representation bisulfite sequencing (RRBS) data from the heart, lung, and liver tissues of healthy cold-blooded horses to identify differentially expressed genes (DEGs), differentially expressed miRNA (DE miRNA) and differentially methylated sites (DMSs) between three types of horse tissues. Additionally, based on integrative omics analysis, we described the observed interactions of epigenetic mechanisms with tissue-specific gene expression alterations. The obtained data allowed identification from 4067 to 6143 DMSs, 9733 to 11,263 mRNAs, and 155 to 185 microRNAs, differentially expressed between various tissues. We pointed out specific genes whose expression level displayed a negative correlation with the level of CpG methylation and miRNA expression and revealed biological processes that they enrich. Furthermore, we confirmed and validated the accuracy of the Next-Generation Sequencing (NGS) results with bisulfite sequencing PCR (BSP) and quantitative PCR (qPCR). This comprehensive analysis forms a strong foundation for exploring the epigenetic mechanisms involved in tissue differentiation, especially the growth and development of the equine heart, lungs, and liver.

Influence of haematological parameters on size of the advanced platelet-rich fibrin+ (A-PRF+) in the horse.

The advanced-PRF+ (A-PRF+) is a platelet concentrate, showing a higher concentration of growth factors, an increased number of cells and looser structure of the fibrin clot than leukocyte-PRF. A high variability in the size of PRF associated with patients, haematological features and centrifugation protocols was reported. The aims of this study were to evaluate the feasibility of A-PRF+ production in the field and the correlation between haematological parameters, macroscopic and microscopic features in equine A-PRF+. Samples from twenty Standardbred horses (3-7 years) were harvested with glass tubes without anticoagulants, previously heated at 37 °C. Blood samples were centrifugated at 1300 rpm for 8 min with a fixed-angle centrifuge and a horizontal centrifuge in the field, at a temperature of 15-17 °C. Clots were measured and placed on the Wound Box® for a 2-min compression. Membranes were measured and fixed in 10% formalin for histological examination. Clot and membrane surface did not differ between sex and centrifuge. Haematological parameters did not show a significant correlation to clot and membrane size. Membranes obtained from both centrifugation protocols showed a loose fibrin structure and cells evenly distributed throughout the clot. Tubes' warming was effective to obtain A-PRF+ clots from all samples, regardless the environmental temperature. Further studies are needed to evaluate the influence of other blood molecules on the A-PRF+ structure and size.

Comparison of inhaled salbutamol and salmeterol for the treatment of arterial hypoxaemia in anaesthetized horses: a randomized clinical trial.

OBJECTIVE: To compare the efficacy of inhaled salbutamol with salmeterol for the treatment of arterial hypoxaemia in anaesthetized horses. STUDY DESIGN: Prospective, randomized, clinical study. ANIMALS: A total of 108 client-owned horses (American Society of Anesthesiologists status I-V) anaesthetized for elective and emergency procedures. METHODS: Horses were premedicated with acepromazine [intramuscularly 0.1 mg kg-1 or intravenously (IV) 0.05 mg kg-1] and xylazine (0.6 mg kg-1 IV). Midazolam (0.06 mg kg-1 IV) and ketamine (2.2 mg kg-1 IV) were combined to induce anaesthesia, and isoflurane in oxygen/air mixture (inspired oxygen fraction 0.7) was used for maintenance of anaesthesia. Mechanical ventilation was initiated without delay using the following ventilator settings: tidal volume 10 mL kg-1, respiratory rate 8 breaths minute-1, inspiratory-to-expiratory time ratio 1:2, no positive end-expiratory pressure. If arterial blood gas analysis revealed PaO2 < 100 mmHg (13.3 kPa), the administration of either inhaled salbutamol (2 µg kg-1) or salmeterol (0.5 µg kg-1) was randomly assigned Blood gas analysis was repeated 15 and 30 minutes after treatment. The intervention was considered successful when PaO2 after treatment ≥ 1.2 × PaO2 before treatment (i.e. ≥20% increase). PaO2 at 15 and 30 minutes was compared between groups using Mann-Whitney U test; p < 0.05 was considered significant. RESULTS: Of the 108 horses, 60 were administered salbutamol, 65% and 60% responded successfully at 15 and 30 minutes, increasing their initial PaO2 by 38% and 44%, respectively. The other 48 horses were administered salmeterol, 35% responded successfully at 15 and 30 minutes, increasing their initial PaO2 by 3% and 4%, respectively. PaO2 was significantly higher after salbutamol than after salmeterol at 15 and 30 minutes. CONCLUSIONS AND CLINICAL RELEVANCE: Using the described protocol, inhaled salbutamol was more effective than salmeterol in improving PaO2 in anaesthetized horses with value < 100 mmHg (13.3 kPa).

Correlation between kinematic parameters, ataxia and ground-to-lip distance in detomidine sedated horses.

BACKGROUND: An accurate evaluation of the degree of sedation is mandatory to adjust the dosage of sedative drugs. OBJECTIVES: To determine the correlation between head height above the ground and ataxia degree in horses sedated with detomidine and the correlation existing between accelerometric variables and both parameters. STUDY DESIGN: Retrospective study. METHODS: Twelve horses were given 0.01 mg/kg of detomidine hydrochloride iv. Measured accelerometric parameters, with one accelerometer positioned between both sacral tuberosities, included speed, stride frequency and length, regularity, dorsoventral, longitudinal, mediolateral and total accelerometric activities, relative force index and dorsoventral, longitudinal and mediolateral parts of the accelerometric activities. Head height above the ground (cm) and subjective ataxia degree were also measured. Baseline values (-15 min) and values measured 5 and 15 min after the injection and then every 15 min for a period of 2 h were obtained. RESULTS: There was a negative and strong correlation between head height above the ground and ataxia degree (Pearson r = -0.78, p < 0.001), particularly during the first 45 min. A significant correlation was found between head height above the ground and almost all accelerometric parameters. This correlation was very strong with stride frequency, regularity and dorsoventral and total accelerometric activities in both cases, but for ataxia, also with total accelerometric activity. MAIN LIMITATIONS: Experimental conditions may not represent real clinical situations. CONCLUSIONS: Stride frequency and regularity are the most reliable parameters to determine degree of sedation and are related to the sedation produced. Ataxia should not be considered a separate property of sedation and does not need to be assessed separately to the depth of sedation.

HISTORIAL: Una evaluación precisa del grado de sedación es importante para ajustar la dosis de drogas sedantes. OBJETIVOS: Determinar la correlación entre la altura de cabeza con respecto al suelo y el grado de ataxia en caballos sedados con detomidina y la correlación que existe entre las variables acelerométricas y ambos parámetros. DISEÑO DEL ESTUDIO: Estudio retrospectivo. MÉTODOS: A doce caballos se les administró 0.01 mg/kg de hidrocloruro de detomidina por vía endovenosa. Parámetros acelerométricos fueron medidos, con un acelerómetro posicionado entre ambas tuberosidades sacrales, que incluyeron velocidad, frecuencia y largo del paso, regularidad, actividades acelerométricas dorso ventral, longitudinal, medio lateral y total, índice de fuerza relativo y partes dorso ventral, longitudinal, medio lateral de actividades acelerométricas. También se midieron la altura de la cabeza sobre el nivel del suelo (cm) y grado de ataxia subjetiva. Se obtuvieron valores de base (­15 min) y valores medidos 5 y 15 min después de la inyección y subsecuentemente cada 15 min por un periódo de 2h. RESULTADOS: Hubo una correlación fuerte, negativa, estadísticamente significativa entre la altura de la cabeza sobre el nivel del suelo y el grado de ataxia (Pearson r = ­0.78, p<0.001), con una correlación mayor durante los primeros 45 minutos. En cuanto a la ataxia, se encontró una correlación significativa entre cabeza sobre el suelo y casi todos los parámetros acelerométricos. Esta correlación fue muy fuerte con la frecuencia y regularidad del paso, actividades acelerométricas dorso ventral y total en ambos casos pero para ataxia también con actividad acelerométrica total. LIMITACIONES PRINCIPALES: Condiciones experimentales no imitan completamente las situaciones clínicas reales. CONCLUSIONES: La frecuencia y regularidad del paso parecen ser los parámetros más confiables para determinar el grado de sedación y están estrictamente relacionados con la sedación producida. Además, la ataxia no debería considerarse como una propiedad separada de la sedación y no necesita ser evaluada en forma separada a la profundidad de la sedación.

Owner-reported health and disease in U.S. senior horses.

BACKGROUND: Information on health care and health status of U.S. senior horses (≥15 years of age) is currently sparse. OBJECTIVES: (A) Provide an overview of owner-reported (1) medical conditions, (2) management/treatment practices for equine metabolic syndrome and pituitary pars intermedia dysfunction (PPID), (3) frequencies of routine health care practices and (4) supplement and pharmaceutical use in U.S. senior horses (≥15 years of age). (B) Evaluate potential risk factors for certain medical conditions and for low routine health care. STUDY DESIGN: Online survey. METHODS: Descriptive and inferential analysis (binomial logistic regression and ANOVA) of 2717 questionnaires from owners of U.S. senior horses. RESULTS: The most common owner-reported veterinary-diagnosed medical conditions were osteoarthritis (30%), dental disorders (15%), lameness (14%), PPID (12%) and ocular disorders (6%). Advancing age was found to be a risk factor for PPID (odds ratio [OR] [95% confidence interval, CI] = 1.14 [1.10-1.18]), dental (OR [95% CI] = 1.18 [1.15-1.22]) and ocular (OR [95% CI] = 1.05 [1.01-1.10]) disorders. Only 36% of horses were free of owner-reported veterinary-diagnosed medical conditions at the time of the survey. During the year prior to the survey, most routine healthcare practices (i.e., veterinary health care, dental care and anthelmintic treatment) were typically undertaken one to two times per year, while farrier visits occurred mostly every 5-6 weeks. Retired senior horses had a higher risk of no health care visits (OR [95% CI] = 2.1 [1.38-3.06]), no dental care (OR [95% CI] = 2.0 [1.31-3.00]) and low farrier attendance (i.e., ≤4 times/year) (OR [95% CI] = 2.4 [1.57-3.63]) compared with senior horses used for pleasure riding. The most frequently administered drug was firocoxib (18%) and joint supplements were the most provided supplements (41%). MAIN LIMITATIONS: Potential recall, response and sampling bias. Risk factor analyses do not establish causal relationships. CONCLUSIONS: Medical conditions are highly prevalent in U.S. senior horses. Retired senior horses have an increased risk of low routine health care.