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1.
Equine Vet J ; 53(2): 331-338, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33566387

RESUMEN

BACKGROUND: Recently, the blacklegged tick (Ixodes scapularis), which is the vector of Borrelia burgdorferi, has undergone a range expansion from the northeastern and mid-west United States to areas of southeastern Canada, including parts of Ontario. Understanding the seroprevalence of antibodies against B. burgdorferi in horses and risk factors for exposure is important for monitoring and preventing this emerging disease. STUDY DESIGN: Cross-sectional study of 551 horses in southern, central, and eastern Ontario, Canada. OBJECTIVES: To assess the seroprevalence of B. burgdorferi in horses in Ontario, Canada; to evaluate risk factors associated with seropositivity; and, to compare the performance of two diagnostic tests. METHODS: Serum samples were obtained from clinically healthy horses in Ontario, Canada, along with completed questionnaires that were used for the risk factor analysis. Sera were tested with a Multiplex ELISA (Animal Health Diagnostic Center, Cornell University) and C6 ELISA (IDEXX SNAP® 4Dx® Plus test, IDEXX Laboratories). RESULTS: The seroprevalence of B. burgdorferi on at least one test was 17% (91/551), though only 15 (16%) horses tested positive with both tests. A spatial cluster of cases was detected in Eastern Ontario. The odds of being seropositive for B. burgdorferi on the C6 ELISA were significantly increased when oak trees were present by pastures (OR = 7.3 (1.8-29.2), P = .005), while the odds were significantly decreased when regular tick checks were performed (OR = 0.1 (0.01-0.7), P = 0.02). MAIN LIMITATIONS: Recruitment focused on known areas with blacklegged ticks as well as areas of higher horse density, which may have led to selection bias. CONCLUSIONS: The expansion of blacklegged tick populations poses an ongoing risk for horses. Assessment of diagnostic testing options and risk factors is important for diagnosis and prevention, and with further investigation this information may be used to propose changes in management.


Asunto(s)
Anaplasma phagocytophilum , Borrelia burgdorferi , Enfermedades de los Caballos , Enfermedad de Lyme , Animales , Estudios Transversales , Enfermedades de los Caballos/epidemiología , Caballos , Enfermedad de Lyme/epidemiología , Enfermedad de Lyme/veterinaria , Ontario/epidemiología , Factores de Riesgo , Estudios Seroepidemiológicos
2.
J Anim Sci ; 99(2)2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33539534

RESUMEN

Conjugated linoleic acid (CLA) improves oxidative stress and mitochondrial biogenesis in various species but has not been thoroughly investigated in horses. We collected blood and muscle samples from lightly exercising horses before and 6 and 12 wk after receiving either soybean oil (CON; n = 5) or CLA (CLA; n = 5) supplementation. Samples were analyzed for markers of mitochondrial characteristics, antioxidant status, oxidative stress, and muscle damage. Data were analyzed using a linear model with repeated measures. In the triceps brachii (TB), citrate synthase (CS) activity was higher in CON than CLA horses (P = 0.003) but was unaffected by diet in the gluteus medius (GM). Integrative (relative to mg protein) cytochrome c oxidase (CCO) activity was higher in TB than the GM (P < 0.0001), while intrinsic (relative to CS) CCO was lower in the TB than the GM (P = 0.02) and tended to be lower in CON than CLA horses (P = 0.06). Neither CS nor integrative CCO activities were affected by time. In the GM, superoxide dismutase activity tended to increase in CON through week 12 (P = 0.10). Over both muscle groups, glutathione peroxidase activity tended to be higher in CON compared with CLA at week 12 (P = 0.06). Malondialdehyde was higher in the TB than the GM (P = 0.0004) but was unaffected by diet, while serum creatine kinase activity tended to be lower in CLA than CON horses (P = 0.07). These results suggest that CLA supplementation may lead to mitochondrial adaptations and prevent myofiber perturbation in skeletal muscle of young, lightly exercised horses.


Asunto(s)
Ácidos Linoleicos Conjugados , Animales , Antioxidantes , Suplementos Dietéticos , Caballos , Ácidos Linoleicos Conjugados/farmacología , Mitocondrias Musculares , Músculo Esquelético
3.
Am J Vet Res ; 82(3): 189-197, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33629894

RESUMEN

OBJECTIVE: To compare the effect of multiple wound dressings on microbial growth in a perfused equine wound model. SAMPLE: Abdominal musculocutaneous flaps from 16 equine cadavers. PROCEDURES: 8 full-thickness skin wound covered were created in each flap. Tissues were perfused with saline (0.9% NaCl) solution. Wounds were inoculated with methicillin-resistant Staphylococcus aureus (MRSA) or Pseudomonas aeruginosa (106 CFUs), incubated, and covered with a dressing containing activated charcoal, boric acid, cadexomer iodine, calcium alginate, manuka honey, nanoparticle silver, or polyhexamethylene biguanide or with a control (nonadherent gauze) dressing. Muscle biopsy specimens were obtained at baseline (immediately prior to dressing application) and 6, 12, 18, and 24 hours later for mean bacterial load (MBL) determination. The MBLs at each subsequent time point were compared with that at baseline within dressing types, and MBLs at each time point were compared among dressing types. RESULTS: MBLs in MRSA-inoculated wounds covered with cadexomer iodine dressings were significantly decreased from baseline at the 6- and 12-hour time points. For P aeruginosa-inoculated wounds, MBLs were significantly increased from baseline in all wounds at various times except for wounds with cadexomer iodine dressings. The MBLs of wounds with cadexomer iodine dressings were lower than all others, although not always significantly different from those for wounds with boric acid, manuka honey, nanoparticle silver, and polyhexamethylene biguanide dressings. CONCLUSIONS AND CLINICAL RELEVANCE: In this nonviable perfused wound model, growth of MRSA and P aeruginosa was most effectively reduced or inhibited by cadexomer iodine dressings. These results and the effect of the dressings on wound healing should be confirmed with in vivo studies.


Asunto(s)
Enfermedades de los Caballos , Staphylococcus aureus Resistente a Meticilina , Colgajo Miocutáneo , Infección de Heridas , Animales , Vendajes , Caballos , Pseudomonas aeruginosa , Cicatrización de Heridas , Infección de Heridas/veterinaria
4.
Am J Vet Res ; 82(3): 225-229, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33629895

RESUMEN

OBJECTIVE: To evaluate synoviocentesis of the equine forelimb digital flexor tendon sheath (DFTS) via a basilar sesamoidean approach (BSA) or distal approach (DA). ANIMALS: 21 healthy adult horses without DFTS-related lameness. PROCEDURES: The forelimbs of each horse underwent the BSA or DA (21 limbs/approach) performed by 1 individual. The volume of synovial fluid (SF) aspirated, time from skin puncture to collection of SF, and number of attempts to place a needle in the DFTS were compared between approaches. RESULTS: An SF sample was successfully aspirated from 16 of 21 (76%) limbs with the BSA and 20 of 21 (95%) limbs with the DA. For the BSA and DA, the number of attempts to obtain SF was 2 and 1, respectively; the median volume of SF obtained was 0.4 and 0.7 mL, respectively; and the median time to SF collection was 17.91 and 18.48 seconds, respectively. Between the approaches, the number of limbs with SF successfully aspirated and number of attempts to collect SF differed significantly, whereas the volume of SF aspirated and time to SF collection did not. CONCLUSIONS AND CLINICAL RELEVANCE: Regarding SF collection from forelimb DFTSs in horses without DFTS-related disease, use of the DA had a greater success rate with fewer attempts, compared with findings for the BSA, which may reflect the relative ease of identifying anatomic landmarks for the DA. Results suggested that a DA for DFTS synoviocentesis in horses appears efficient and effective and may minimize limb trauma by requiring fewer attempts for SF sample collection, compared with a BSA.


Asunto(s)
Miembro Anterior , Enfermedades de los Caballos , Animales , Caballos , Líquido Sinovial , Tendones/cirugía
5.
Am J Vet Res ; 82(3): 207-217, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33629897

RESUMEN

OBJECTIVE: To determine whether administration of trimethoprim-sulfadiazine (TMS), detomidine (DET), or TMS plus DET would be associated with changes in ECG repolarization parameters in horses. ANIMALS: 9 healthy adult horses. PROCEDURES: Each horse received 4 treatments in a blinded, randomized, crossover study design as follows: TMS, 16 to 24 mg/kg, IV; DET, 0.015 to 0.02 mg/kg, IV; TMS plus DET; and saline (0.9% NaCl) solution. Surface ECG traces were obtained over 24 hours, and repolarization parameters were measured at predefined time points after each treatment and compared with a 2-way ANOVA for repeated measures. RESULTS: Heart rate-corrected QT intervals (QTc) were significantly increased after administration of DET (mean ± SD difference in QTc, 36.57 ± 23.07 milliseconds; increase of 7%) and TMS plus DET (44.96 ± 29.16 milliseconds; increase of 9%), compared with baseline (before treatment) values and values after administration of saline solution. Saline solution and TMS alone did not affect QTc. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of DET or TMS plus DET was associated with a significant and possibly clinically relevant prolongation of QTc, with prolongation of 7% to 9%, a range that is considered as a risk factor for the development of cardiac arrhythmias in people. Results were unexpected because DET is considered to be a safe sedative for horses.


Asunto(s)
Sulfadiazina , Trimetoprim , Animales , Estudios Cruzados , Electrocardiografía/veterinaria , Frecuencia Cardíaca , Caballos , Imidazoles , Trimetoprim/efectos adversos
6.
Am J Vet Res ; 82(3): 198-206, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33629903

RESUMEN

OBJECTIVE: To assess the motion of the proximal sesamoid bones (PSBs) relative to the third metacarpal bone (MC3) of equine forelimbs during physiologic midstance loads. SAMPLE: 8 musculoskeletally normal forelimbs (7 right and 1 left) from 8 adult equine cadavers. PROCEDURES: Each forelimb was harvested at the mid-radius level and mounted in a material testing system so the hoof could be moved in a dorsal direction while the radius and MC3 remained vertical. The PSBs were instrumented with 2 linear variable differential transformers to record movement between the 2 bones. The limb was sequentially loaded at a displacement rate of 5 mm/s from 500 N to each of 4 loads (1.8 [standing], 3.6 [walking], 4.5 [trotting], and 10.5 [galloping] kN), held at the designated load for 30 seconds while lateromedial radiographs were obtained, and then unloaded back to 500 N. The position of the PSBs relative to the transverse ridge of the MC3 condyle and angle of the metacarpophalangeal (fetlock) joint were measured on each radiograph. RESULTS: The distal edge of the PSBs moved distal to the transverse ridge of the MC3 condyle at 10.5 kN (gallop) but not at lower loads. The palmar surfaces of the PSBs rotated away from each other during fetlock joint extension, and the amount of rotation increased with load. CONCLUSIONS AND CLINICAL RELEVANCE: At loads consistent with a high-speed gallop, PSB translations may create an articular incongruity and abnormal bone stress distribution that contribute to focal subchondral bone lesions and PSB fracture in racehorses.


Asunto(s)
Fracturas Óseas , Enfermedades de los Caballos , Huesos del Metacarpo , Huesos Sesamoideos , Animales , Miembro Anterior , Fracturas Óseas/veterinaria , Caballos , Articulaciones , Huesos del Metacarpo/diagnóstico por imagen , Huesos Sesamoideos/diagnóstico por imagen
7.
Artículo en Inglés | MEDLINE | ID: mdl-33533815

RESUMEN

Visceral leishmaniasis (VL) is a neglected tropical disease caused by the Leishmania infantum parasite. The protozoan is able to infect several domestic and wild mammals. Since the first report on Leishmania spp. infection in horses in South America, leishmaniasis in equids has been highlighted in Brazil. A molecular epidemiological survey was carried out to verify the occurrence of Leishmania spp. DNA in horses and donkeys, in leishmaniases endemic areas in Sao Paulo State, Brazil. To this end, blood samples were obtained from 107 horses and 36 donkeys and subjected to DNA extraction followed by PCR targeting the ITS-1 region. Among the horses and donkeys, 1.87% (2/107) and 8.33% (3/36) were positive by PCR, respectively. The DNA sequencing of the ITS-1 amplification products confirmed L. infantum DNA in these animals. Our results suggest that horses and donkeys from non-VL and VL endemic areas of São Paulo State may be infected by the parasite.


Asunto(s)
Equidae/sangre , Caballos/sangre , Leishmania infantum/genética , Leishmaniasis Visceral/diagnóstico , Animales , Brasil , ADN , Leishmaniasis Visceral/veterinaria , Reacción en Cadena de la Polimerasa
8.
Artículo en Ruso | MEDLINE | ID: mdl-33591677

RESUMEN

Since the ancient times, epidemics affect the processes proceeding in various spheres of life of human society. Hence, steadfast attention of historians to this biological phenomenon and its investigation. Quite a lot of of research studies is devoted to the first-rate epidemics, for instance, the famous «Black Death¼ in the middle of XIV century. At the same time, far from all such occurrences were properly interpreted in historical literature. Among little-studied and factually unknown epidemics, the pestilence, the plague, that struck the Russian state in the second half of 60s-early 70s of XVI century, stands out for. The article considers this occurrence, demonstrates its origin, time and geographical limits and also analyzes its consequences.


Asunto(s)
Epidemias , Peste , Animales , Personal de Salud , Caballos , Humanos , Peste/epidemiología , Federación de Rusia/epidemiología
9.
Arch Virol ; 166(2): 571-579, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33410993

RESUMEN

This study compared concurrent and separate primary vaccination against equid alphaherpesviruses 1 and 4, genus Varicellovirus, subfamily Alphaherpesvirinae, family Herpesviridae, and equine influenza A virus, genus Alphainfluenzavirus, family Orthomyxoviridae. Their vernacular names are equine herpesvirus 1 and 4 (EHV1/4) and equine influenza virus (EIV). Infection with these respiratory pathogens is associated with loss of performance, interruption of training schedules, and on occasion, cancellation of equestrian events. Vaccination is highly recommended, and for some activities it is a mandatory requirement of the relevant authority. As there is a dearth of information relating to the impact of concurrent vaccination on the antibody response to EHV and EIV vaccines, they are usually administered separately, often 2 weeks apart. In a previous study of booster vaccination in Thoroughbred racehorses, concurrent vaccination with whole-virus inactivated carbopol-adjuvanted EHV and EIV vaccines did not impact negatively on the antibody response. In this study, investigations were extended to concurrent versus separate primary vaccination of warmblood foals. A field study was conducted to compare the immune response to a carbopol-adjuvanted EHV vaccine and an immune stimulating complex (ISCOM)-adjuvanted EI vaccine administered concurrently and 2 weeks apart. No adverse clinical reactions were observed, the pattern of EI and EHV antibody response was similar for both groups, and there was no evidence that concurrent primary vaccination compromised the humoral response. The results are of relevance to horse owners who wish to decrease veterinary costs, limit handling of young animals, and simplify record keeping by vaccinating concurrently.


Asunto(s)
Infecciones por Herpesviridae/inmunología , Vacunas contra Herpesvirus/inmunología , Enfermedades de los Caballos/inmunología , Caballos/inmunología , Virus de la Influenza A/inmunología , Vacunas contra la Influenza/inmunología , Adyuvantes Inmunológicos/administración & dosificación , Animales , Anticuerpos Antivirales/inmunología , Formación de Anticuerpos/inmunología , Femenino , Enfermedades de los Caballos/virología , Caballos/virología , Inmunidad Humoral/inmunología , Inmunización Secundaria/métodos , Infecciones por Orthomyxoviridae/inmunología , Infecciones por Orthomyxoviridae/virología , Vacunación/métodos , Vacunas de Productos Inactivados/inmunología
10.
Int J Nanomedicine ; 16: 1-14, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33442247

RESUMEN

Introduction: The present study reports on examination of the effects of encapsulating the tyrosine kinase inhibitors (TKIs) vandetanib and lenvatinib into a biomacromolecular ferritin-based delivery system. Methods: The encapsulation of TKIs was performed via two strategies: i) using an active reversible pH-dependent reassembly of ferritin´s quaternary structure and ii) passive loading of hydrophobic TKIs through the hydrophobic channels at the junctions of ferritin subunits. After encapsulation, ferritins were surface-functionalized with folic acid promoting active-targeting capabilities. Results: The physico-chemical and nanomechanical analyses revealed that despite the comparable encapsulation efficiencies of both protocols, the active loading affects stability and rigidity of ferritins, plausibly due to their imperfect reassembly. Biological experiments with hormone-responsive breast cancer cells (T47-D and MCF-7) confirmed the cytotoxicity of encapsulated and folate-targeted TKIs to folate-receptor positive cancer cells, but only limited cytotoxic effects to healthy breast epithelium. Importantly, the long-term cytotoxic experiments revealed that compared to the pH-dependent encapsulation, the passively-loaded TKIs exert markedly higher anticancer activity, most likely due to undesired influence of harsh acidic environment used for the pH-dependent encapsulation on the TKIs' structural and functional properties. Conclusion: Since the passive loading does not require a reassembly step for which acids are needed, the presented investigation serves as a solid basis for future studies focused on encapsulation of small hydrophobic molecules.


Asunto(s)
Sistemas de Liberación de Medicamentos , Ferritinas/química , Ácido Fólico/química , Compuestos de Fenilurea/farmacología , Piperidinas/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Quinazolinas/farmacología , Quinolinas/farmacología , Animales , Antineoplásicos/farmacología , Materiales Biocompatibles/química , Muerte Celular/efectos de los fármacos , Línea Celular , Movimiento Celular/efectos de los fármacos , Células Clonales , Difusión , Portadores de Fármacos/química , Caballos , Humanos , Concentración de Iones de Hidrógeno , Compuestos de Fenilurea/química , Piperidinas/química , Quinazolinas/química , Quinolinas/química , Propiedades de Superficie
11.
J Anim Sci ; 99(1)2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33515482

RESUMEN

The effect of hay type on the microbiome of the equine gastrointestinal tract is relatively unexplored. Our objective was to characterize the cecal and fecal microbiome of mature horses consuming alfalfa or Smooth Bromegrass (brome) hay. Six cecally cannulated horses were used in a split-plot design run as a crossover in two periods. The whole plot treatment was ad libitum access to brome or alfalfa hay fed over two 21-d acclimation periods with subplots of sampling location (cecum and rectum) and sampling hour. Each acclimation period was followed by a 24-h collection period where cecal and fecal samples were collected every 3 h for analysis of pH and volatile fatty acids (VFA). Fecal and cecal samples were pooled and sent to a commercial lab (MR DNA, Shallowater, TX) for the amplification of the V4 region of the 16S rRNA gene and sequenced using Illumina HiSeq. The main effects of hay on VFA, pH, and taxonomic abundances were analyzed using the MIXED procedure of SAS 9.4 with fixed effects of hay, hour, location, period, and all possible interactions and random effect of horse. Alpha and beta diversities were analyzed using the R Dame package. Horses fed alfalfa had greater fecal than cecal pH (P ≤ 0.05), whereas horses fed brome had greater cecal than fecal pH (P ≤ 0.05). Regardless of hay type, total VFA concentrations were greater (P ≤ 0.05) in the cecum than in feces, and alfalfa resulted in greater (P ≤ 0.05) VFA concentrations than brome in both sampling locations. Alpha diversity was greater (P ≤ 0.05) in fecal compared with cecal samples. Microbial community structure within each sampling location and hay type differed from one another (P ≤ 0.05). Bacteroidetes were greater (P ≤ 0.05) in the cecum compared with the rectum, regardless of hay type. Firmicutes and Firmicutes:Bacteroidetes were greater (P ≤ 0.05) in the feces compared with cecal samples of alfalfa-fed horses. In all, fermentation parameters and bacterial abundances were impacted by hay type and sampling location in the hindgut.


Asunto(s)
Alimentación Animal , Microbiota , Alimentación Animal/análisis , Animales , Ciego/metabolismo , Dieta/veterinaria , Heces , Fermentación , Caballos , ARN Ribosómico 16S/genética , ARN Ribosómico 16S/metabolismo
12.
Arch Virol ; 166(3): 881-884, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33433694

RESUMEN

In the present study, we serosurveyed the exposure of 222 draft horses to different arboviruses in the city of Santa Fe, Argentina. Plaque reduction neutralization tests confirmed exposure to Fort Sherman virus (FSV), Saint Louis encephalitis virus (SLEV), West Nile virus (WNV), and Río Negro virus (RNV). Apparently, Western and Eastern equine encephalitis viruses did not circulate in the population tested. The confirmation of five seroconversions for WNV, FSV, and SLEV and the association between prevalence and age are indicative of recent circulation. These results highlight the importance of considering draft horses in arboviral surveillance in urban and rural areas of developing countries.


Asunto(s)
Infecciones por Alphavirus/epidemiología , Anticuerpos Antivirales/sangre , Infecciones por Bunyaviridae/epidemiología , Encefalitis de San Luis/epidemiología , Enfermedades de los Caballos/epidemiología , Fiebre del Nilo Occidental/epidemiología , Alphavirus/inmunología , Alphavirus/aislamiento & purificación , Infecciones por Alphavirus/veterinaria , Animales , Argentina/epidemiología , Infecciones por Bunyaviridae/veterinaria , Virus de la Encefalitis de San Luis/inmunología , Virus de la Encefalitis de San Luis/aislamiento & purificación , Encefalitis de San Luis/veterinaria , Enfermedades de los Caballos/virología , Caballos , Orthobunyavirus/inmunología , Orthobunyavirus/aislamiento & purificación , Seroconversión , Fiebre del Nilo Occidental/veterinaria , Virus del Nilo Occidental/inmunología , Virus del Nilo Occidental/aislamiento & purificación
13.
Dis Aquat Organ ; 143: 51-56, 2021 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-33506815

RESUMEN

Myxobolus cerebralis (Hofer, 1903), the etiological agent of salmonid whirling disease, reportedly matures in only the oligochaete 'Tubifex tubifex'. The concept of 'T. tubifex' is problematic because it is renowned as a species complex (or having 'strains'), and many sequences ascribed to this taxon in GenBank are misidentified or indicate several cryptic species. These facts cast doubt on the long-held notion that M. cerebralis is strictly host-specific to the single definitive host, T. tubifex. Herein, as part of an ongoing regional whirling disease monitoring project, oligochaetes (452 specimens) were collected from 31 riverine sites in western North Carolina (August through September 2015) and screened for infection by M. cerebralis. The species-specific nested PCR for M. cerebralis was positive for 8 oligochaete specimens from the French Broad River Basin (Mill Creek and Watauga River) and New River Basin (Big Horse Creek). We individually barcoded these M. cerebralis-positive oligochaete specimens using cytochrome oxidase 1 (CO1) primers and then conducted a Bayesian inference phylogenetic analysis. We identified 2 oligochaete genotypes: one sister to a clade comprising Limnodrilus udekemianus (Haplotaxida: Naididae) and another sister to Limnodrilus hoffmeisteri. This is the first detection of M. cerebralis from an oligochaete in the SE USA and the first detection of M. cerebralis from an oligochaete other than T. tubifex. These results suggest that other non-T. tubifex definitive hosts can harbor the pathogen and should be considered in the context of fish hatchery biosecurity and monitoring wild trout streams for M. cerebralis and whirling disease in the southeastern USA.


Asunto(s)
Enfermedades de los Peces , Enfermedades de los Caballos , Myxobolus , Oligoquetos , Animales , Teorema de Bayes , Eucariontes , Caballos , Myxobolus/genética , North Carolina , Filogenia
14.
Am J Vet Res ; 82(2): 125-131, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33480274

RESUMEN

OBJECTIVE: To investigate the effects of triamcinolone acetonide (TA) and methylprednisolone acetate (MPA) on the viability of resident cells within the fibrocartilage on the dorsal surface of the deep digital flexor tendon (FC-DDFT) and fibrocartilage on the flexor surface of the navicular bone (FC-NB) of horses. SAMPLE: 12 to 14 explants of FC-DDFT and of FC-NB from grossly normal forelimbs of 5 cadavers of horses aged 9 to 15 years without evidence of musculoskeletal disease. PROCEDURES: Explants were incubated with culture medium (control) or TA-supplemented (0.6 or 6 mg/mL) or MPA-supplemented (0.5 or 5 mg/mL) medium for 6 or 24 hours. Explant metabolic activity and percentage of dead cells were assessed with a resazurin-based assay and live-dead cell staining, respectively, at each time point. Drug effects were assessed relative to findings for the respective control group. RESULTS: Application of TA (at both concentrations) did not significantly change the cell viability of FC-DDFT explants. For FC-NB explants, TA at 6 mg/mL significantly reduced the metabolic activity and increased the percentage of dead cells at both time points. With either MPA concentration, FC-DDFT and FC-NB explants had reduced metabolic activity and an increased percentage of dead cells at 24 hours, whereas only MPA at 5 mg/mL was cytotoxic at the 6-hour time point. CONCLUSIONS AND CLINICAL RELEVANCE: In ex vivo explants, TA was less cytotoxic to equine FC-DDFT and FC-NB cells, compared with MPA. Further work is warranted to characterize the drugs' transcriptional and translational effects as well as investigate their cytotoxicity at lower concentrations.


Asunto(s)
Enfermedades de los Caballos , Huesos Tarsianos , Corticoesteroides , Animales , Supervivencia Celular , Fibrocartílago , Enfermedades de los Caballos/tratamiento farmacológico , Caballos
15.
Am J Vet Res ; 82(2): 138-143, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33480276

RESUMEN

OBJECTIVE: To investigate the effects of orally administered trazodone on intraocular pressure (IOP), pupil diameter measured in the vertical plane (ie, vertical pupil diameter [VPD]), selected physical examination variables, and sedation level in healthy equids. ANIMALS: 7 horses and 1 pony. PROCEDURES: Food was withheld for 12 hours prior to drug administration. After baseline (time 0) sedation scoring, physical examination, and measurement of IOP and VPD, equids received 1 dose (approx 6 mg/kg) of trazodone orally. Examination and measurement procedures were repeated 0.5, 1, 2, 4, 8, 12, and 24 hours after drug administration. Blood samples were collected at each time point for analysis of plasma trazodone concentrations. Repeated-measures analysis was used to compare examination results between downstream time points and baseline. RESULTS: 7 of 8 equids had mild sedation from 0.5 to 8 hours after treatment; compared with baseline values, mean IOP was significantly lower from 0.5 hours to 8 hours, mean VPD was significantly smaller at 0.5 hours, and mean rectal temperature was significantly lower from 1 to 8 hours after drug administration. Adverse effects (signs of excitement in 1 equid and sweating in 4) were self-limiting and considered minor. Mean maximum plasma concentration of trazodone was 1,493 ng/mL 0.75 hours after administration, and terminal half-life of the drug was 9.96 hours. CONCLUSIONS AND CLINICAL RELEVANCE: The described oral dose of trazadone elicited sedation with a few self-limiting adverse effects in the study sample. Drug effects on IOP and VPD may alter ocular examination findings. Further investigation is warranted prior to use of trazodone for sedation in equids, particularly those with ophthalmic conditions.


Asunto(s)
Trazodona , Animales , Caballos , Presión Intraocular , Examen Físico , Pupila , Tonometría Ocular , Trazodona/farmacología
16.
Am J Vet Res ; 82(2): 152-157, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33480279

RESUMEN

OBJECTIVE: To evaluate surfactant protein D (SP-D) concentrations in serum and bronchoalveolar lavage fluid (BALF) from young healthy horses on pasture or housed in a typical barn. ANIMALS: 20 young healthy horses. PROCEDURES: Horses were randomly assigned to 1 of 2 groups (pasture, n = 10; barn, 10), and serum and BALF samples were collected for SP-D determination at baseline (all horses on pasture) and 2 weeks and 4 weeks after the barn group of horses was relocated from the pasture to the barn. Other evaluations included physical and tracheoscopic examinations. Findings were compared within and between groups. RESULTS: Physical and tracheoscopic examinations, CBC, and serum biochemical analysis did not reveal evidence of respiratory disease, and no significant differences were present within and between groups. Serum SP-D concentrations did not significantly differ within and between groups, but BALF SP-D concentrations were significantly lower for the barn group at 2 weeks but not at 4 weeks, compared with baseline. The BALF SP-D concentration-to-BALF total protein concentration ratio was < 1.5 and did not significantly differ within and between groups. CONCLUSIONS AND CLINICAL RELEVANCE: A mild decrease was evident in the concentration of SP-D in the BALF collected from young healthy horses after 2 weeks of exposure to a barn environment. The clinical importance of this finding remains to be determined.


Asunto(s)
Enfermedades de los Caballos , Enfermedades Respiratorias , Animales , Lavado Broncoalveolar/veterinaria , Líquido del Lavado Bronquioalveolar , Caballos , Proteína D Asociada a Surfactante Pulmonar , Enfermedades Respiratorias/veterinaria
17.
Am J Vet Res ; 82(2): 99-104, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33480277

RESUMEN

OBJECTIVE: To determine the median time to maximum concentration (tmax) of amikacin in the synovial fluid of the tarsocrural joint following IV regional limb perfusion (IVRLP) of the drug in a saphenous vein of horses. ANIMALS: 7 healthy adult horses. PROCEDURES: With each horse sedated and restrained in a standing position, a 10-cm-wide Esmarch tourniquet was applied to a randomly selected hind limb 10 cm proximal to the point of the tarsus. Amikacin sulfate (2 g diluted with saline [0.9% NaCl] solution to a volume of 60 mL) was instilled in the saphenous vein over 3 minutes with a peristaltic pump. Tarsocrural synovial fluid samples were collected at 5, 10, 15, 20, 25, and 30 minutes after completion of IVRLP. The tourniquet was removed after collection of the last sample. Amikacin concentration was quantified by a fluorescence polarization immunoassay. Median maximum amikacin concentration and tmax were determined. RESULTS: 1 horse was excluded from analysis because an insufficient volume of synovial fluid for evaluation was obtained at multiple times. The median maximum synovial fluid amikacin concentration was 450.5 µg/mL (range, 304.7 to 930.7 µg/mL), and median tmax was 25 minutes (range, 20 to 30 minutes). All horses had synovial fluid amikacin concentrations ≥ 160 µg/mL (therapeutic concentration for common equine pathogens) at 20 minutes after IVRLP. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that, in healthy horses, maintaining the tourniquet for 20 minutes after IVRLP of amikacin in a saphenous vein was sufficient to achieve therapeutic concentrations of amikacin in the tarsocrural joint.


Asunto(s)
Amicacina , Preparaciones Farmacéuticas , Animales , Antibacterianos , Miembro Anterior , Caballos , Perfusión/veterinaria , Líquido Sinovial
18.
Phys Chem Chem Phys ; 23(1): 320-328, 2021 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-33346267

RESUMEN

Considering the remarkable applicability of ionic liquids (ILs) in bio-catalysis involving enzymes, herein, we report new IL based aqueous microemulsions as a catalytic reactor for cytochrome c (Cyt-c). Microemulsions (µEs), comprising water as the polar component, imidazolium (cation) and dioctylsulfosuccinate (AOT) (anion) based biamphiphilic ionic liquid (BAIL) as the surfactant and a hydrophobic ionic liquid (HIL) as the non-polar component have been prepared and characterized. The use of BAIL has promoted the formation of µEs without any co-surfactant, owing to its higher surface activity. The effect of ester- or amide-functionalization of the alkyl chain of the imidazolium cation of BAILs on the phase behavior of µEs has been investigated. The prepared µEs have been characterized via conductivity, dynamic light scattering (DLS), UV-vis absorption and steady-state fluorescence (using external polarity probes) techniques. The prepared µEs have been employed as nano-reactors for exploring the catalytic activity of Cyt-c. The formed BAIL-water nano-interfaces in reverse µEs have exerted a positive effect on the catalytic activity of Cyt-c stored in a water pool of reverse µEs. A five-fold higher rate constant in µEs as compared to buffer establishes µEs as a better catalytic medium. Furthermore, the differing nature of nano-interfaces created by BAILs and water in reverse µEs, depending on the functionalization of the alkyl chain of the cationic part of BAIL, has exerted varying influence on the catalytic activity of Cyt-c. It is expected that the present work will result in providing a versatile platform for the creation of new IL and water based µEs for bio-catalytic applications.


Asunto(s)
Citocromos c/química , Emulsiones/química , Líquidos Iónicos/química , Tensoactivos/química , Animales , Catálisis , Ácido Dioctil Sulfosuccínico/química , Guayacol/química , Caballos , Peróxido de Hidrógeno/química , Imidazoles/química , Oxidación-Reducción , Agua/química
20.
Am J Vet Res ; 82(1): 28-38, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33369492

RESUMEN

OBJECTIVE: To evaluate with CT the characteristics of brain tissue disruption and skull damage in cadaveric heads of adult horses caused by each of 6 firearm-ammunition combinations applied at a novel anatomic aiming point. SAMPLE: 53 equine cadaveric heads. PROCEDURES: Heads placed to simulate that of a standing horse were shot with 1 of 6 firearm-ammunition combinations applied at an aiming point along the external sagittal crest of the head where the 2 temporalis muscles form an inverted V. Firearm-ammunition combinations investigated included a .22-caliber long rifle pistol firing a 40-grain, plated lead, solid-core or hollow-point bullet (HPB); a semiautomatic 9-mm pistol firing a 115-grain, jacketed HPB; a semiautomatic .223-caliber carbine firing a 55-grain, jacketed HPB; a semiautomatic .45-caliber automatic Colt pistol firing a 230-grain, jacketed HPB; and a 12-gauge shotgun firing a 1-oz rifled slug. Additional heads placed in a simulated laterally recumbent position were shot with the semiautomatic 9-mm pistol-HPB combination. All heads underwent CT before and after being shot, and images were evaluated for projectile fragmentation, skull fracture, and cerebrum, cerebellum, and brainstem disruption. RESULTS: Computed tomography revealed that all firearm-ammunition combinations caused disruption of the cerebrum, cerebellum, and brainstem that appeared sufficient to result in instantaneous death of a live horse. Hollow-point ammunition was as effective as solid-core ammunition with regard to brain tissue disruption. Brain tissue disruption was not affected by head positioning. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that the examined firearm-ammunition combinations, when applied at a novel aiming point, appear to be reasonable options for euthanasia of horses.


Asunto(s)
Armas de Fuego , Enfermedades de los Caballos , Heridas por Arma de Fuego , Animales , Encéfalo , Cadáver , Eutanasia Animal , Caballos , Masculino , Cráneo/diagnóstico por imagen , Tomografía Computarizada por Rayos X/veterinaria , Heridas por Arma de Fuego/veterinaria
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