Lipidomic Analysis of Immune Activation in Equine Leptospirosis and \u3cem\u3eLeptospira\u3c/em\u3e-Vaccinated Horses

Currently available diagnostic assays for leptospirosis cannot differentiate vaccine from infection serum antibody. Several leptospiral proteins that are upregulated during infection have been described, but their utility as a diagnostic marker is still unclear. In this study, we undertook a lipidomics approach to determine if there are any differences in the serum lipid profiles of horses naturally infected with pathogenic Leptospira spp. and horses vaccinated against a commercially available bacterin. Utilizing a high-resolution mass spectrometry serum lipidomics analytical platform, we demonstrate that cyclic phosphatidic acids, diacylglycerols, and hydroperoxide oxidation products of choline plasmalogens are elevated in the serum of naturally infected as well as vaccinated horses. Other lipids of interest were triacylglycerols that were only elevated in the serum of infected horses and sphingomyelins that were increased only in the serum of vaccinated horses. This is the first report looking at the equine serum lipidome during leptospiral infection and vaccination

Comparaison du suivi médical longitudinal contrôlé et des méthodologies d'entraînement entre les chevaux de polo et les athlètes de haut niveau pratiquant des efforts analogues (hockey sur glace, roller hockey, water polo)

Le suivi médical longitudinal contrôlé, instauré par divers textes législatifs, est le garant de la santé des athlètes humains de haut niveau. Même si pour le polo, de telles règles ne sont pas applicables, le vétérinaire joue un rôle de premier ordre quant-à la santé et au bien-être des poneys de polo, soumis à rude épreuve dans ce sport de contact explosif se jouant à vive allure. Comparativement aux disciplines humaines que sont le hockey sur glace, le roller hockey et le water polo, on note de grandes similitudes dans la physiologie de l'effort requis pour les athlètes équins au polo, avec une intrication étroite des différentes filières bioénergétiques, où le métabolisme anaérobie, lactique et surtout alactique, jouent un rôle majeur, malgré un effort de fond d'ordre aérobie. De toutes ces singularités dérivent des méthodologies d'entraînement fondées sur les mêmes principes empiriques, en attente d'une approche plus scientifique et rationnelle, afin d'obtenir des performances maximales d'athlètes, humains et équins, exerçant leurs efforts parfois au-delà de leurs limites physiologiques.MAISONS-ALFORT-Ecole Vétérin (940462302) / SudocSudocFranceF

Mise en place, utilisation et intérêts en pratique itinérante d'un endoscope embarqué (Dynamic Respiratory Scope Optomed) chez le cheval

L'examen endoscopique des voies respiratoires supérieures permet de visualiser la morphologie et le fonctionnement de diverses structures laryngées et pharyngées chez le cheval. Cet examen est particulièrement indiqué lors de bruit respiratoire et/ou d'insuffisance à l'effort. L'intérêt de l'endoscopie à l'effort par l'utilisation du Dynamic Respiratory Scope est de diagnostiquer des obstructions dynamiques. Après plusieurs versions, l'endoscope est actuellement un outil de diagnostique précis, adapté et facile d'utilisation en pratique vétérinaire itinérante. Il sera donc intéressant dans les années à venir, de proposer des traitements pour les nouvelles pathologies découvertes grâce à ce type d'examen. De plus ce type d'endoscopie pourra être proposé comme examen complémentaire au cours des visites d'achat ou lors de contre performance évaluées par le vétérinaire praticien sans la nécessité de référer le client vers par un centre de référence.MAISONS-ALFORT-Ecole Vétérin (940462302) / SudocSudocFranceF

Intérêt du dosage sanguin de la protéine D de surfactant (SP-D) lors d'inflammation des voies respiratoires profondes

peer reviewedLa protéine D de surfactant (SP-D), principalement synthétisée par les pneumocytes de type II est un composant important de l'immunité pulmonaire innée. L'objectif de cette étude était de comparer les concentrations sériques de SP-D chez des chevaux souffrant d'inflammation des voies respiratoires profondes (IAD) avec des chevaux contrôles. Des échantillons de sang ont été collectés sur 42 Trotteurs Français au repos et 60 minutes après un test d'effort standardisé sur tapis roulant. Sur base de la cytologie du lavage bronchoalvéolaire, 22 chevaux souffraient d'IAD et 20 chevaux ont été utilisés comme contrôles. Les concentrations sériques de SP-D chez les chevaux avec IAD étaient significativement augmentées par rapport à celles des chevaux contrôles. L'exercice n'a pas significativement influencé les concentrations sériques de SP-D. Ces résultats mettent en évidence que l'IAD est associé à une augmentation détectable, quoique modérée, des taux sanguins de SP-D. La concentration sérique en protéine D de surfactant pourrait représenter un biomarqueur sanguin potentiellement utile et facilement accessible lors d'inflammation des voies respiratoires chez le cheval.Surfactant protein D (SP-D), mainly synthetised by alveolar type II tells, isone important component of innate pulmonary immunity. The aim of the study was te sompare serum SP-D concentrations in horses with and without inflammatory airway disease (IAD). Venous blond samples were collected from 42 Standardbred racehorses at rest and 60 min after performing a standardised treadmill exercise test. Based on bronchoalveolar lavage cytology, 22 horses were defined as IAD-affected and 20 classified as controls. Serum concentrations of SP-D in IAD-affected horses were significantly higher than those of control horses, both at rest and after exercise. Within each group of horses (IAD and control), no significant influence of exercise was found on serum SP-D levels. This is he first study determining serum SP-D concentrations in a noninfectious, naturally occuring form of louver airway inflammation in horses. The results highlight that IAD is associated with a detectable, though moderate, increase of circulating SP-D levels. Serum concentration of surfactant protein D could represent a potentially valuable and readily accessible blond biomarker of equine louver airway inflammation

Measurement of ascorbic acid concentration and glutathione peroxidase activity in biological samples collected from horses with recurrent airway obstruction

Objective—To measure the ascorbic acid (AA) concentration in bronchoalveolar lavage fluid (BALF) and cellular glutathione peroxidase (cGPx) activity in RBCs and WBCs from peripherally obtained blood and in cells from BALF to determine whether differences existed between the 2 major redox systems in recurrent airway obstruction (RAO)-affected and -nonaffected (control) horses and between systemic and local pulmonary responses in the glutathione redox system. Animals—16 adult horses in pairs: 8 healthy (control) and 8 RAO-affected horses. Procedures—Physical examination data and biological samples were collected from horses before (remission), during, and after (recovery) environmental challenge with dusty straw and hay. At each stage, BALF cell AA concentration and RBC, WBC, and BALF cell cGPx activity were measured. Results—Compared with control horses, RAO-affected horses had significantly higher cGPx activity in RBCs at all points and in WBCs during remission and challenge. The BALF cell cGPx activity was higher in RAO-affected horses during recovery than during remission The BALF cell AA concentration did not differ significantly in control horses at any point, but total and free AA concentrations were significantly lower in RAO-affected horses during the challenge period than during remission and recovery periods. Conclusions and Clinical Relevance—High cGPx activity suggested this redox system was upregulated during exposure to dusty straw and hay to combat oxidative stress, as AA was depleted in RAO-affected horses. The relative delay and lack of comparative increase in cGPx activity within the local environment (represented by BALF cells), compared with that in RBCs and WBCs, might contribute to disease in RAO-affected horses

Surfactant alterations in horses with recurrent airway obstruction at various clinical stages

Objective — To evaluate the phospholipid composition and function of surfactant in horses with recurrent airway obstruction (RAO) at various clinical stages and compare these properties with findings in horses without RAO.\ud \ud Animals — 7 horses with confirmed RAO and 7 without RAO (non-RAO horses).\ud \ud Procedures — Pairs of RAO-affected and non-RAO horses were evaluated before, during, and after exposure to hay. Evaluations included clinical scoring, lung function testing, airway endoscopy, and bronchoalveolar lavage fluid (BALF) absolute and differential cell counts. Cell-free BALF was separated into crude surfactant pellet and supernatant by ultracentrifugation, and phospholipid and protein concentrations were determined. Phospholipid composition of crude surfactant pellets and surface tension were evaluated with high-performance liquid chromatography and a pulsating bubble surfactometer, respectively. Findings were compared statistically via mixed-effects, repeated-measures ANOVA.\ud \ud Results — Total phospholipid concentration in BALF was lower in RAO-affected versus non-RAO horses at all sample collection times. In the RAO-affected group, total phospholipid concentration was lower during exposure to hay than before or after exposure. There were no significant differences in BALF protein concentration, percentages of phospholipid classes, or surface tension between or within groups of horses.\ud \ud Conclusions and Clinical Relevance — All clinical stages of RAO-affected horses were characterized by low surfactant concentration in BALF. Exacerbation of RAO led to an additional decrease in surfactant concentration. Causes for low surfactant concentration in RAO-affected horses remain to be determined. Low phospholipid concentration may render RAO-affected horses more susceptible than unaffected horses to surfactant alterations and contribute to clinical disease status and progression

Equine serum levels of choline plasmalogen (PlsC) hydroperoxides (N = 15 per group).

<p>Con: controls; Vacc: vaccinated; Infect: infected. *, p < 0.01; **, p < 0.05. R = ratio of the ion intensity for the endogenous hydroperoxide to the ion intensity of the stable isotope internal standard.</p