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1.
Can Vet J ; 65(5): 481-487, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38694739

RESUMO

Background: An adequate supply of trace elements is very important for equine neonates, as deficiencies can lead to health problems and even death. Objective: This study investigated serum concentrations of selenium (Se), copper (Cu), and zinc (Zn) in neonatal foals up to the 8th day of life. The influences of disease, age, and failure of passive transfer (FPT) on these concentrations were analyzed. Animals and procedure: Serum concentrations of Se, Cu, and Zn were determined from blood samples of 93 foals by means of inductively coupled plasma mass spectrometry. The foals were divided into 2 groups based on health status: clinically sick (n = 51) and clinically healthy (n = 42). The latter group was further divided into foals with FPT (n = 20) and those without (n = 22). Results: Mean serum concentrations for Se, Cu, and Zn were 60 ± 40 µg/L, 0.25 ± 0.22 mg/L, and 605 ± 285 µg/L, respectively. A significant influence of age on serum Cu concentration was observed (P < 0.0001). No differences were observed between any of the serum concentrations in clinically sick and clinically healthy foals on the 1st day of life. The FPT status was not associated with reduced serum concentrations of Se, Cu, or Zn. Conclusion and clinical relevance: It is not necessary to supplement trace elements in all foals with FPT.


Concentrations sériques de sélénium, de cuivre et de zinc chez les poulains nouveau-nés : influence de l'échec du transfert passif et des changements liés à l'âge. Contexte: Un apport suffisant en oligo-éléments est très important pour les nouveau-nés équins, car des carences peuvent entraîner des problèmes de santé, voire la mort. Objectif: Cette étude a examiné les concentrations sériques de sélénium (Se), de cuivre (Cu) et de zinc (Zn) chez les poulains nouveau-nés jusqu'au 8ème jour de vie. Les influences de maladies, de l'âge et de l'échec du transfert passif (FPT) sur ces concentrations ont été analysées. Animaux et procédure: Les concentrations sériques de Se, Cu et Zn ont été déterminées à partir d'échantillons de sang de 93 poulains au moyen d'une spectrométrie de masse à plasma à couplage inductif. Les poulains ont été divisés en 2 groupes en fonction de leur état de santé: cliniquement malades (n = 51) et cliniquement sains (n = 42). Ce dernier groupe a été divisé en poulains avec FPT (n = 20) et ceux sans (n = 22). Résultats: Les concentrations sériques moyennes de Se, Cu et Zn étaient respectivement de 60 ± 40 µg/L, 0,25 ± 0,22 mg/L et 605 ± 285 µg/L. Une influence significative de l'âge sur la concentration sérique de Cu a été observée (P < 0,0001). Aucune différence n'a été observée entre les concentrations sériques chez les poulains cliniquement malades et cliniquement sains au premier jour de leur vie. Le statut FPT n'était pas associé à une réduction des concentrations sériques de Se, Cu ou Zn. Conclusion et pertinence clinique: Il n'est pas nécessaire de supplémenter tous les poulains en oligo-éléments avec FPT.(Traduit par Dr Serge Messier).


Assuntos
Animais Recém-Nascidos , Cobre , Doenças dos Cavalos , Selênio , Zinco , Animais , Cavalos/sangue , Selênio/sangue , Cobre/sangue , Zinco/sangue , Animais Recém-Nascidos/sangue , Doenças dos Cavalos/sangue , Feminino , Masculino , Envelhecimento/sangue , Imunidade Materno-Adquirida , Oligoelementos/sangue
2.
Artigo em Alemão | MEDLINE | ID: mdl-38701799

RESUMO

OBJECT AND AIM: This study presents the individual course of estradiol-17ß and progesterone concentrations in blood during the reproductive cycle in mares in order to point out physiological differences between individual animals and to aid in the interpretation of hormone values. MATERIAL AND METHODS: Concentrations of estradiol-17ß and progesterone were determined in seven mares over the course of their cycle. One mare was excluded from the study due to a physiologically deviating cycle. In addition, the mares' ovaries were examined via ultrasound on a daily basis in order to match the hormone values to morphological changes of the ovaries. RESULTS: In some cases, the mares showed considerable individual differences in their hormone concentrations, which also differed from the published comparative values in the literature. For example, two mares showed progesterone levels above basal levels at the time of ovulation. The postovulatory progesterone concentrations of the mares are characterized by marked fluctuations, which makes it difficult to provide reference values in the different sections of the corpus luteum phase. The length of the plateau phases averaged 12.3±1.5 days. The mare with double ovulation showed the highest progesterone concentrations. CONCLUSION: The measurement of plasma progesterone levels in mares should be interpreted only in the context of other test results. The very wide variation in estradiol-17ß concentrations makes it questionable whether the determination of this hormone value is of diagnostic value. CLINICAL RELEVANCE: When interpreting steroid hormone values in the ingravid cycle of a mare, the individual concentration courses must be taken into consideration, as they may deviate significantly from the published reference values.


Assuntos
Estradiol , Progesterona , Animais , Cavalos/sangue , Cavalos/fisiologia , Feminino , Progesterona/sangue , Estradiol/sangue , Ciclo Estral/fisiologia , Ciclo Estral/sangue , Ovário/fisiologia , Ovário/diagnóstico por imagem , Ovário/anatomia & histologia , Ovulação/fisiologia , Ovulação/sangue
3.
Res Vet Sci ; 173: 105276, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38677075

RESUMO

Androgens are produced in both sexes. In females produced by the adrenal gland and the ovaries they play a crucial role in regulating ovarian function, estrogen synthesis and follicular growth. Age leads to a reduction in androgen concentrations, although, at present, these mechanisms are not elucidated in mares. The objective of this study was to evaluate the concentrations of testosterone (T), androstenedione (A4) and dehydroepiandrosterone (DHEA) in mares of different ages. Blood samples were drawn from seventy cyclic Spanish Purebred mares belonging to five age groups: 3-5 years, 6-9 years, 10-13 years, 14-16 years and > 16 years. The concentrations of T, A4 and DHEA were determined by EIA, validated specifically for horses. Mares aged 3-5, 6-9 and 10-13 years had higher T concentrations (P < 0.05) than mares aged >16 years, and mares aged 6-9 years had also higher concentrations than those 14-16 years old (P < 0.05). A4 concentrations were lower (P < 0.05) in mares >16 years old when compared with those of other age groups. DHEA concentrations were lower (P < 0.05) in mares 14-16 years and > 16 years old when compared with those of other age groups. DHEA was positively correlated with T (r = 0.61; P < 0.05) and A4 (r = 0.51; P < 0.05). Age induces reduction in androgens' synthesis in physiologically cyclic Spanish Purebred mares. These physiological variations must be duly considered for a correct and objective interpretation of the analytical data.


Assuntos
Envelhecimento , Androstenodiona , Desidroepiandrosterona , Testosterona , Animais , Cavalos/fisiologia , Cavalos/sangue , Feminino , Desidroepiandrosterona/sangue , Testosterona/sangue , Androstenodiona/sangue , Envelhecimento/fisiologia , Androgênios/sangue , Fatores Etários , Ciclo Estral/fisiologia , Ciclo Estral/sangue
4.
J Vet Intern Med ; 38(3): 1825-1834, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38647141

RESUMO

BACKGROUND: Pharmacokinetics of amikacin administered IV to neonatal foals are described, but little data are available regarding the plasma concentrations contributed by concurrent intra-articular (IA) administration. HYPOTHESIS/OBJECTIVES: Compare the pharmacokinetics of amikacin when the total dose is administered IV compared to being divided between IV and IA routes of administration in neonatal foals and predict the plasma concentrations from various combined IV and IA dosing regimens. ANIMALS: Eight healthy neonatal foals. METHODS: Foals received 3 amikacin treatment protocols: (1) IV-only (25 mg/kg q24h IV), (2) concurrent IV and IA (16.7 mg/kg q24h IV and 8.3 mg/kg q24h into 1 tarsocrural joint), and (3) IA-only (8.3 mg/kg q24h into 1 tarsocrural joint). Protocols were administered for 3 days beginning at 7, 14, and 21 days of age. Plasma concentrations ≥53 µg/mL at 30 minutes were considered therapeutic for isolates with intermediate susceptibility. RESULTS: Foal age was a significant variable. The IV-only protocol met or exceeded the 30-minute plasma concentrations considered therapeutic (mean µg/mL [95% confidence interval, CI]) in 7- to 9-day-old (54.0 [52.2-56.9]), 14- to 16-day-old (58.1 [55.2-61.0]), and 21- to 23-day-old (66.6 [63.7-69.6]) foals. Concurrent IV and IA protocol did not reach the 30-minute concentration considered therapeutic in 7- to 9-day-old foals (46.5 [43.6-49.4]) but did in 14- to 16-day-old (62.9 [60.0-65.8]) and 21-to 23-day-old (62.6 [59.7-65.6]) foals. CONCLUSIONS AND CLINICAL IMPORTANCE: Concurrent IV and IA administration of amikacin produces 30-minute plasma concentrations considered therapeutic in foals 14 to 23 days old, but concentrations observed in younger foals might be below those considered therapeutic for isolates with intermediate susceptibility to amikacin.


Assuntos
Amicacina , Animais Recém-Nascidos , Antibacterianos , Animais , Amicacina/farmacocinética , Amicacina/administração & dosagem , Amicacina/sangue , Cavalos/sangue , Injeções Intra-Articulares/veterinária , Antibacterianos/farmacocinética , Antibacterianos/administração & dosagem , Antibacterianos/sangue , Masculino , Feminino , Injeções Intravenosas/veterinária
5.
Am J Vet Res ; 85(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38346393

RESUMO

OBJECTIVE: To determine the effects of a single dose of the NSAIDs phenylbutazone, firocoxib, flunixin meglumine, and ketoprofen on concentrations of growth factors and cytokines in autologous protein solution (APS) and platelet-rich plasma (PRP). ANIMALS: 6 adult university-owned horses. METHODS: For the first phase, 6 horses were randomized to receive ketoprofen (1,000 mg) or flunixin meglumine (500 mg) IV. Blood was obtained and processed for APS (Pro-Stride) and PRP (Restigen) before and 6 hours after administration of NSAIDs. Horses underwent a 2-week washout period, after which the protocol was repeated using a crossover design. For the second phase, following at least a 2-week washout period, the study protocol was repeated with phenylbutazone (1 g) or firocoxib (57 mg) administered orally. Plasma was collected 6 hours after administration for evaluation of drug concentrations, and APS and PRP were analyzed for concentrations of drug, platelets, leukocytes, and several growth factors and cytokines (PDGF, fibroblast growth factor, TGF-ß1, IL-1ß, IL-10, IL-6, IL-8, and tumor necrosis factor-α) before and 6 hours after administration of NSAIDs using immunoassays. RESULTS: There were no significant differences in concentrations of cytokines or growth factors before or after administration of any NSAID. There were significant differences in concentrations of leukocytes and platelets based on both product and time. NSAID concentrations in plasma were not significantly different from concentrations in APS and PRP. CLINICAL RELEVANCE: These results help guide clinicians on the appropriate use of these NSAIDs in conjunction with the processing of APS and PRP, which is unlikely to significantly alter the final product after single-dose administration.


Assuntos
Anti-Inflamatórios não Esteroides , Citocinas , Cavalos , Plasma Rico em Plaquetas , Animais , 4-Butirolactona/administração & dosagem , 4-Butirolactona/efeitos adversos , 4-Butirolactona/análogos & derivados , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/efeitos adversos , Citocinas/sangue , Citocinas/metabolismo , Cavalos/sangue , Cavalos/metabolismo , Cetoprofeno/administração & dosagem , Cetoprofeno/efeitos adversos , Fenilbutazona/administração & dosagem , Fenilbutazona/efeitos adversos , Plasma Rico em Plaquetas/metabolismo , Sulfonas/administração & dosagem , Sulfonas/efeitos adversos , Distribuição Aleatória
6.
J Vet Pharmacol Ther ; 47(3): 187-192, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38197553

RESUMO

There are two FDA-approved bisphosphonate products, clodronate (Osphos®) and tiludronate (Tildren®), for use in horses. It is hypothesized that bisphosphonates can produce analgesic effects and prevent proper healing of microcracks in bone. Therefore, bisphosphonate use is banned in racehorses. However, bisphosphonates have a short detection window in the blood before sequestration in the skeleton, making the reliability of current drug tests questionable. Seven exercising Thoroughbred horses were administered clodronate (1.8 mg/kg i.m.), and four were administered saline. RNA was isolated from peripheral blood mononuclear cells (PBMCs) collected immediately before a single dose of clodronate or saline and then on Days 1, 6, 28, 56 and 182 post-dose. mRNA was sequenced and analysed for differentially expressed transcripts. While no single transcripts were differentially expressed, pathway analysis revealed that p38 MAPK (p = .04) and Ras (p = .04) pathways were upregulated, and cadherin signalling (p = .02) was downregulated on Day 1. Previously investigated biomarkers, cathepsin K (CTSK) and type 5 acid phosphatase (ACP5), were analysed with RT-qPCR in a targeted gene approach, with no significant difference observed. A significant effect of time on gene expression for ACP5 (p = .03) and CTSK (p < .0001) was observed. Thus, these genes warrant further investigation for detecting clodronate use over time.


Assuntos
Conservadores da Densidade Óssea , Ácido Clodrônico , Regulação da Expressão Gênica , Animais , Cavalos/sangue , Ácido Clodrônico/farmacologia , Conservadores da Densidade Óssea/farmacologia , Conservadores da Densidade Óssea/administração & dosagem , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Feminino , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo
7.
J Vet Pharmacol Ther ; 45(5): 467-472, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35652132

RESUMO

Grapiprant is a prostaglandin E2 receptor antagonist that has been found to be an effective anti-inflammatory in dogs and that is devoid of some of the adverse effects associated with traditional NSAIDs that elicit their effects through inhibition of PGE2 production. Previously published reports have described the pharmacokinetics of this drug in horses when administered at 2 mg/kg; however, pharmacodynamic effects in this species have yet to be described. The objective of the current study was to describe the pharmacokinetics and pharmacodynamics of grapiprant at a higher dose. Eight horses received a single oral administration of 15 mg/kg. Plasma concentrations were determined for 96 h using liquid chromatography-tandem mass spectrometry. Non-compartmental analysis was used to determine pharmacokinetic parameters. Pharmacodynamic effects were assessed ex vivo by stimulating blood samples with PGE2 and determining TNF-ɑ concentrations. Maximum concentration, time to maximum concentration and area under the curve were 327.5 (188.4-663.0) ng/ml, 1 (0.75-2.0) hour and 831.8 (512.6-1421.6) h*ng/ml, respectively. The terminal half-life was 11.1 (8.27-21.2) hr. Significant stimulation of TNF alpha was noted for 2-4 h post-drug administration. Results of this study suggest a short duration of EP4 receptor engagement when administered at a dose of 15 mg/kg.


Assuntos
Cavalos , Compostos de Sulfonilureia , Fator de Necrose Tumoral alfa , Administração Oral , Animais , Área Sob a Curva , Meia-Vida , Cavalos/sangue , Imidazóis , Prostaglandinas E , Piridinas , Compostos de Sulfonilureia/farmacocinética
8.
Sci Rep ; 12(1): 1918, 2022 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-35121736

RESUMO

Domestic horses are widely used for physically demanding activities but the effect of exercise on their learning abilities has not been explored. Horses are also frequently exposed to stressors that may affect their learning. Stress and exercise result in the release of glucocorticoids, noradrenaline and other neurotransmitters that can influence learning. It is not currently possible to directly measure concentrations of neurotransmitters in the brains of behaving horses, however the inference of neurobiological processes from peripheral markers have been widely used in studies of human cognition. We assigned 41 horses to either ridden exercise, uncontrollable stress or inactivity and evaluated their acquisition of an industry-style aversive instrumental learning task. Exercised horses achieved the learning criterion in the fewest number of trials compared to the stressed and inactive horses whose performance did not differ. The exercised horses' salivary cortisol concentrations decreased during learning whereas the concentrations of the other groups increased. Spearman's correlations revealed that horses with the highest cortisol concentrations required the most trials to reach the criterion. We present novel data that exercise prior to learning may enhance the acquisition of learning in horses. Conversely, activities that expose horses to uncontrollable stressors causing strong cortisol release may impair learning. It is proposed that these effects may be due to the influence of neurotransmitters such as cortisol and noradrenaline on brain regions responsible for learning.


Assuntos
Comportamento Animal , Encéfalo/fisiologia , Cognição , Cavalos/fisiologia , Aprendizagem , Condicionamento Físico Animal , Esforço Físico , Animais , Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/sangue , Feminino , Frequência Cardíaca , Cavalos/sangue , Cavalos/psicologia , Hidrocortisona/metabolismo , Masculino , Saliva/metabolismo
9.
Artigo em Inglês | MEDLINE | ID: mdl-35032890

RESUMO

Nicotine is classified as a stimulant, and its use is banned in horse racing and equestrian sports by the International Federation of Horseracing Authorities and the Fédération Équestre Internationale, respectively. Because nicotine is a major alkaloid of tobacco leaves, there is a potential risk that doping control samples may be contaminated by tobacco cigarettes or smoke during sample collection. In order to differentiate the genuine doping and sample contamination with tobacco leaves, it is necessary to monitor unique metabolites as biomarkers for nicotine administration and intake. However, little is known about the metabolic fate of nicotine in horses. This is the first report of comprehensive metabolism study of nicotine in horses. Using liquid chromatography/electrospray ionization high-resolution mass spectrometry, we identified a total of 17 metabolites, including one novel horse-specific metabolite (i.e., 4-hydroxy-4-(3-pyridyl)-N-methylbutanamide), in post-administration urine samples after nasoesophageal administration of nicotine to three thoroughbred mares; eight of these compounds were confirmed based on reference standards. Among these metabolites, N-hydroxymethylnorcotinine was the major urinary metabolite in equine, but it could only be tentatively identified by mass spectral interpretation due to the lack of reference material. In addition, we developed simultaneous quantification methods for the eight target analytes in plasma and urine, and applied them to post-administration samples to establish elimination profiles of nicotine and its metabolites. The quantification results revealed that trans-3'-hydroxycotinine could be quantified for the longest period in both plasma (72 h post-administration) and urine (96 h post-administration). Therefore, this metabolite is the most appropriate monitoring target for nicotine exposure for the purpose of doping control due to its long detection times and the availability of its reference material. Further, we identified trans-3'-hydroxycotinine as a unique biomarker allowing differentiation between nicotine administration and sample contamination with tobacco leaves.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Dopagem Esportivo/métodos , Cavalos/sangue , Cavalos/urina , Espectrometria de Massas/métodos , Nicotina/sangue , Nicotina/urina , Animais , Biomarcadores/sangue , Biomarcadores/urina , Dopagem Esportivo/prevenção & controle , Estimulantes Ganglionares/sangue , Estimulantes Ganglionares/urina , Limite de Detecção
10.
Sci Rep ; 12(1): 1308, 2022 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-35079068

RESUMO

Trypanozoon infections in equids are caused by three parasite species in the Trypanozoon subgenus: Trypanosoma equiperdum, T. brucei and T. evansi. They are respectively responsible for infectious diseases dourine, nagana and surra. Due to the threat that Trypanozoon infection represents for international horse trading, accurate diagnostic tests are crucial. Current tests suffer from poor sensitivity and specificity, due in the first case to the transient presence of parasites in the blood and in the second, to antigenic cross-reactivity among Trypanozoon subspecies. This study was designed to develop a microsphere-based immunoassay for diagnosing equine trypanosomosis. We tested beads coated with eight Trypanosoma spp. recombinant antigens: enolase, GM6, PFR1, PFR2, ISG65, VSGat, RoTat1.2 and JN2118HU. Of these, GM6 was identified as the best candidate for the serological diagnosis of Trypanozoon infections in equids. Using a receiver operating characteristic (ROC) analysis on 349 equine sera, anti-GM6 antibodies were detected with an AUC value of 0.994 offering a sensitivity of 97.9% and a specificity of 96.0%. Our findings show that the GM6 antigen is a good target for diagnosing equine trypanosomosis using a microsphere-based immunoassay. This promising assay could be a useful alternative to the official diagnostic tool for equine trypanosomosis.


Assuntos
Doenças dos Cavalos/diagnóstico , Cavalos/parasitologia , Microesferas , Testes Sorológicos/métodos , Trypanosoma/imunologia , Tripanossomíase/diagnóstico , Tripanossomíase/veterinária , Animais , Anticorpos Antiprotozoários/sangue , Anticorpos Antiprotozoários/imunologia , Área Sob a Curva , Ensaio de Imunoadsorção Enzimática/métodos , Doenças dos Cavalos/parasitologia , Cavalos/sangue , Curva ROC , Proteínas Recombinantes/imunologia , Tripanossomíase/sangue , Tripanossomíase/parasitologia , Glicoproteínas Variantes de Superfície de Trypanosoma/imunologia
11.
J Biochem Mol Toxicol ; 36(2): e22955, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34755932

RESUMO

The objective of this study was to evaluate the biomarkers of exposure to boron, nickel, arsenic, and antimony in an industrial region, evaluating the bioaccumulation in biological substrates and the correlation with biomarkers such as hematological parameters. Through indication of the accumulation of some minerals in the horse's biological substrates reflects environmental pollution. Moreover, an additional aim of the study was to show whether these contaminants have an influence on the hematological parameters in horses. Blood, serum, mane, and tail samples from 20 horses from an industrial area were analyzed to determine boron (B), nickel (Ni), arsenic (As), antimony (Sb) concentration. Hematological parameters (red blood cell [RBC], white blood cells [WBC], hemoglobin [Hb], hematocrit [Hct], mean corpuscular volume [MCV], mean corpuscular hemoglobin [MCH], mean corpuscular hemoglobin concentration [MCHC], platelet [PLT]) as a biomarker of blood in relation to the bioaccumulation of these elements were analyzed also. Descriptive statistical analysis was performed and single regression analysis (Pearson) and multiple regression analysis (p < 0.05) between blood factors, As, B, Ni, and Sb concentrations, and for each mineral in different substrate, respectively. Results showed a significant correlation between tail and mane concentrations with serum and blood for boron concentration (r = -1 p < 0.05). No significant correlation between sample (feed, hay, mane, tail, and water) concentrations and As, Ni, and Sb were found. A significantly negative correlation with blood parameters (r = -1 p < 0.05) was observed in Boron concentration for mane and tail. This suggests that the mane and tail may be a potential means to investigate suspected exposure to excessive levels of trace minerals.


Assuntos
Antimônio/sangue , Boro/sangue , Cavalos/sangue , Níquel/sangue , Animais , Arsênio , Biomarcadores/sangue , Hematócrito
12.
Equine Vet J ; 54(1): 153-158, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33453066

RESUMO

BACKGROUND: Matrix fentanyl patches have not been investigated in horses and may represent an effective means of providing analgesia over an extended time period without venous catheterisation. OBJECTIVES: To describe the pharmacokinetics of a matrix transdermal fentanyl patch in horses. STUDY DESIGN: Randomised experiment, Latin-square design. METHODS: Six adult horses were given each of three treatments with a 96-hour washout. For each treatment, two 100 µg/h matrix fentanyl patches were applied to the inguinal region (TXA), metacarpus (TXM) or ventral tail base (TXT) for 72 hours. Blood samples for fentanyl analysis were obtained and heart rate (HR), respiratory rate (RR) and rectal temperature (RT) were measured at various time points for 96 hours. Fentanyl plasma concentrations were measured with LC-MS/MS for pharmacokinetic analysis. A mixed-effects model was used to analyse pharmacodynamic variables. RESULTS: The time to maximum plasma concentration, maximum plasma concentration and area under the curve extrapolated to infinity were 10 ± 3.79, 14.3 ± 5.13 and 10.3 ± 4.8 hours; 2.07 ± 0.74, 1.55 ± 0.53 and 2.07 ± 0.72 ng/mL; and 46.6 ± 9.3, 44.6 ± 6.0 and 46.2 ± 7.68 ng hours/mL for TXA, TXM and TXT respectively. There was no significant difference among groups. There was no significant change from baseline or among treatment groups with regard to HR, RR or RT (P > .1 for all). MAIN LIMITATIONS: There was no intravenous treatment group for determination of bioavailability. CONCLUSIONS: Fentanyl was rapidly absorbed and persisted in the plasma for up to 96 hours. No adverse effects of treatment on HR, RR or RT were observed. Further controlled prospective studies are needed to determine what plasma concentration, if any, of fentanyl achieves an analgesic effect in horses when administered via a transdermal patch system.


Assuntos
Analgésicos Opioides/farmacocinética , Fentanila , Cavalos/sangue , Espectrometria de Massas em Tandem , Administração Cutânea , Animais , Cromatografia Líquida/veterinária , Fentanila/farmacocinética , Espectrometria de Massas em Tandem/veterinária
13.
Pol J Vet Sci ; 24(3): 393-397, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34730308

RESUMO

The aim of the study was to determine the utility of maximum eye temperature measured by infrared thermography (IRT) as a stress indicator compared with plasma cortisol concentration in Thoroughbred and Arabian racehorses. The study included thirty racehorses undergoing standard training for racing. Measurements of maximum eye temperature and blood collection for plasma cortisol concentration were carried out before training (BT), and within 5 (5AT) and 120 minutes (120AT) after the end of the each training session in three repetitions, with a monthly interval. Both parameters were elevated at 5AT compared to BT (p⟨0.001). Compared to BT, at 120AT the maximum eye temperature remained elevated (p⟨0.001) and plasma cortisol concentration decreased (p⟨0.001). The study indicated significant weak correlations (r=0.220; p⟨0.001) between both measurements at all time points. The results support the use of IRT technique to monitor the response of horses to stress, potentially improving animal management and welfare.


Assuntos
Temperatura Corporal , Olho , Cavalos/sangue , Hidrocortisona/sangue , Condicionamento Físico Animal , Animais , Cavalos/fisiologia , Esportes , Estresse Fisiológico
14.
Vet Parasitol ; 296: 109511, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34237517

RESUMO

The management of equine strongyles has become problematic over the last decade because of an increased prevalence of drug-resistant isolates worldwide. Therapeutic options are therefore limited, leaving macrocyclic lactones as the most often effective drug class. However, their lipophilic properties result in a long-lasting elimination that could favour drug resistance selection. As a result, ivermectin treatment in lactating mares could promote suboptimal exposure of their foal parasites to ivermectin, thereby selecting for more resistant worms. To test for this putative transfer, we selected two groups of six foal-mare pairs, one group of mares receiving ivermectin and the other being left untreated. We compared faecal egg count trajectories in foals from the two groups and quantified plasma ivermectin concentrations in ivermectin treated mares and their foals during seven days. Our results showed limited but sustained plasmatic exposure of foals associated with non-significant faecal egg count reduction (P = 0.69). This suggests that ivermectin treatment in lactating mares results in suboptimal exposure to the drug in their foal.


Assuntos
Doenças dos Cavalos , Ivermectina , Lactação , Animais , Resistência a Medicamentos , Feminino , Doenças dos Cavalos/tratamento farmacológico , Cavalos/sangue , Ivermectina/sangue , Ivermectina/uso terapêutico , Contagem de Ovos de Parasitas/veterinária
15.
Molecules ; 26(9)2021 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-34066773

RESUMO

Besides human red blood cells (RBC), a standard model used in AFM-single cell force spectroscopy (SCFS), little is known about apparent Young's modulus (Ea) or adhesion of animal RBCs displaying distinct cellular features. To close this knowledge gap, we probed chicken, horse, camel, and human fetal RBCs and compared data with human adults serving as a repository for future studies. Additionally, we assessed how measurements are affected under physiological conditions (species-specific temperature in autologous plasma vs. 25 °C in aqueous NaCl solution). In all RBC types, Ea decreased with increasing temperature irrespective of the suspension medium. In mammalian RBCs, adhesion increased with elevated temperatures and scaled with reported membrane sialic acid concentrations. In chicken only adhesion decreased with higher temperature, which we attribute to the lower AE-1 concentration allowing more membrane undulations. Ea decreased further in plasma at every test temperature, and adhesion was completely abolished, pointing to functional cell enlargement by adsorption of plasma components. This halo elevated RBC size by several hundreds of nanometers, blunted the thermal input, and will affect the coupling of RBCs with the flowing plasma. The study evidences the presence of a RBC surface layer and discusses the tremendous effects when RBCs are probed at physiological conditions.


Assuntos
Camelus/sangue , Adesão Celular/fisiologia , Galinhas/sangue , Eritrócitos/citologia , Cavalos/sangue , Microscopia de Força Atômica/métodos , Análise de Célula Única/métodos , Temperatura , Adulto , Animais , Membrana Celular/metabolismo , Humanos
16.
Vet J ; 274: 105706, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34148016

RESUMO

Sorbitol dehydrogenase (SDH) activity is one of the most sensitive and specific markers for hepatocellular injury in horses, but its reported lability makes it impractical for use in many clinical settings. To date, stability of SDH in equine samples has only been evaluated in a limited number of studies in serum samples of horses with activities within reference intervals. The objective of the study was to determine pre-analytical stability of equine SDH activity in heparinized plasma stored at different temperatures for up to 72 h. Twenty client-owned horses admitted to a veterinary teaching hospital for any reason were included in the study. Blood samples collected in lithium-heparin tubes were immediately centrifuged and SDH activity was analyzed within 1 h of collection (T0). Aliquots of plasma were stored at room temperature, 4 °C and -20 °C and SDH activity was re-analyzed after 4 h (T4), 24 h (T24) and 72 h (T72). A significant difference from values measured at T0 was found for samples stored at room temperature (P = 0.022) and -20 °C (P < 0.001), but not at 4 °C. The activity of SDH was within ±20% of that measured at T0 for all samples under all temperature conditions stored for 4 h, and for all samples stored at 4 °C for 24 h. Bland-Altman plots revealed narrow limits of agreement at T4 for all storage temperatures and at T24 for samples stored at 4 °C. The mean absolute percentage error and 95th percentile of the absolute percentage error were lower for samples stored at 4 °C than those stored at room temperature or -20 °C. The activity of SDH has adequate stability for 4 h regardless of storage temperature and 24 h if stored at 4 °C across a wide range of values. Knowledge of the pre-analytical stability of SDH may permit its broader use in assessing hepatic disorders in horses.


Assuntos
Cavalos/sangue , L-Iditol 2-Desidrogenase/sangue , Manejo de Espécimes/veterinária , Animais , Feminino , Heparina , L-Iditol 2-Desidrogenase/química , Fígado/enzimologia , Masculino , Manejo de Espécimes/métodos , Temperatura , Fatores de Tempo
17.
Front Immunol ; 12: 668328, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33968072

RESUMO

This review describes the research aimed at the development of universal antivenom against elapid neurotoxic snake venoms. The antivenoms produced in Thailand in the 1980s were of low potency, especially against the elapid venoms. This was thought to be due to the low immunogenicity of the α-neurotoxins, which are the most lethal toxins in these venoms. Comparisons of various α-neurotoxin conjugates and polymers, and also different immunological adjuvants, showed that the adjuvant used is the major determinant in the antibody response in horses. The potent Freund's adjuvant was not used due to its severe local side-effect in horses. Therefore, a novel immunization protocol termed 'low dose, low volume multi-site' was developed for use in horses. This immunization protocol has led to the production of highly potent monospecific antivenoms against several elapid and viperid venoms, and two potent polyspecific antivenoms, one against 4 neurotoxic and another against 3 hematotoxic venoms. The immunization protocol has also led to other improvements in antivenom production including: several fold increases in antiserum potency, a reduction in the time required to reach therapeutically useful antibody titers, a 90% reduction in the amount of venom used, and 100% of the horses responding to the immunization program. This development is partly responsible for significant decrease in the Thailand's annual snakebite death toll from a few dozens to mostly nil in recent years. Finally, a simple and novel immunization strategy, using a 'diverse toxin repertoire' composed of numerous elapid toxin fractions as immunogen, was proposed and tested. This immunization procedure has resulted in the successful production of a widely paraspecific antiserum against at least 36 neurotoxic venoms of 28 species encompassing 10 genera and from 20 countries on four continents, and possibly against all elapid venoms with α-neurotoxins as the lethal toxins. These results indicate that, with optimizations of the composition of the 'diverse toxin repertoire', the immunization scheme and antibody fractionation to increase the antivenom neutralizing potency, an effective universal antivenom against the neurotoxic elapid snakes of the world can be produced.


Assuntos
Antivenenos/uso terapêutico , Venenos Elapídicos/antagonistas & inibidores , Neurotoxinas/antagonistas & inibidores , Mordeduras de Serpentes/tratamento farmacológico , Adjuvantes Imunológicos/uso terapêutico , Animais , Especificidade de Anticorpos , Antivenenos/efeitos adversos , Antivenenos/biossíntese , Venenos Elapídicos/administração & dosagem , Venenos Elapídicos/sangue , Venenos Elapídicos/imunologia , Elapidae , Epitopos , Cavalos/sangue , Cavalos/imunologia , Humanos , Imunização , Neurotoxinas/administração & dosagem , Neurotoxinas/sangue , Neurotoxinas/imunologia , Mordeduras de Serpentes/imunologia , Mordeduras de Serpentes/metabolismo
18.
J Vet Diagn Invest ; 33(4): 703-710, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34047216

RESUMO

Many point-of-care (POC) analyzers are available for the measurement of electrolytes and acid-base status in animals. We assessed the precision of the i-STAT Alinity v, a recently introduced POC analyzer, and compared it to 2 commonly used and previously validated POC analyzers (i-STAT 1, Stat Profile pHOx Ultra). Precision was evaluated by performing multiple analyses of whole blood samples from healthy dogs, cats, and horses on multiple i-STAT Alinity v analyzers. For comparison between analyzers, whole blood samples from dogs and cats presented to the emergency room were run concurrently on all 3 POC instruments. Reported values were compared by species (dogs and cats only) using Pearson correlation, and all values from all species were analyzed together for the Bland-Altman analysis. Results suggested that the i-STAT Alinity v precision was very good, with median coefficients of variability <2.5% for all measured parameters (except the anion gap), with variable ranges of coefficients of variation. In addition, good-to-excellent correlation was observed between the i-STAT Alinity v and i-STAT 1, and between the i-STAT Alinity v and Stat Profile pHOx Ultra for all parameters in both cats and dogs, respectively. In this cohort, the i-STAT Alinity v had clinically acceptable bias compared to the currently marketed analyzers and can be used for monitoring measured analytes in cats and dogs, although serial measurements in a single animal should be performed on the same analyzer whenever possible.


Assuntos
Gasometria/veterinária , Gatos/sangue , Cães/sangue , Eletrólitos/sangue , Cavalos/sangue , Sistemas Automatizados de Assistência Junto ao Leito , Animais , Gasometria/instrumentação , Gasometria/métodos , Reprodutibilidade dos Testes
19.
Drug Test Anal ; 13(8): 1527-1534, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33870655

RESUMO

Clodronate is a non-nitrogen-containing bisphosphonate drug approved in equine veterinary medicine. Clodronate is prohibited for use in competition horses; therefore, to set up an appropriate control, detection times and screening limits are required. The quantitative method in plasma consisted of addition of chloromethylene diphosphonic acid as internal standard. Automated sample preparation comprised a solid phase extraction with weak anion exchange properties on microplate. After methylation of the residue with trimethyl orthoacetate, analysis was conducted by high-performance liquid chromatography-tandem mass spectrometry. Using a weighting factor of 1/(concentration)2 , good linearity was observed in the range of 1 to 500 ng/ml, with low limits of detection and quantification of 0.5 and 1 ng/ml, respectively. Precision and accuracy determined at four concentrations were satisfactory, with an error percentage less than 15%. Absence of carry-over and good stability of clodronic acid in plasma after a long-term storage at -20°C were verified. The method was successfully applied to the quantification of clodronic acid in plasma samples from horses administered with a single intramuscular administration of Osphos® at a mean dose of 1.43 ± 0.07 mg/kg. The observed detection time will be verified in a clinical population study conducted in diseased horses.


Assuntos
Analgésicos não Narcóticos/sangue , Ácido Clodrônico/sangue , Cavalos/sangue , Animais , Automação , Cromatografia Líquida de Alta Pressão , Dopagem Esportivo , Injeções Intramusculares , Masculino , Reprodutibilidade dos Testes , Extração em Fase Sólida , Espectrometria de Massas em Tandem
20.
Cells ; 10(4)2021 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-33920705

RESUMO

Clenbuterol, the ß2-adrenoceptor agonist, is gaining growing popularity because of its effects on weight loss (i.e., chemical liposuction). It is also popular in bodybuilding and professional sports, due to its effects that are similar to anabolic steroids. However, it is prohibited by anti-doping control. On the other hand, it is suggested that clenbuterol can inhibit the inflammatory process. The cells from 14 untrained and 14 well-trained race horses were collected after acute exercise and cultured with clenbuterol. The expressions of CD4, CD8, FoxP3, CD14, MHCII, and CD5 in PBMC, and reactive oxygen species (ROS) production, as well as cell proliferation, were evaluated by flow cytometry. In addition, IL-1ß, IL-4, IL-6, IL-10, IL-17, INF-γ and TNF-α concentrations were evaluated by ELISA. ß2-adrenoceptor stimulation leads to enhanced anti-inflammatory properties in well-trained horses, as do low doses in untrained animals. In contrast, higher clenbuterol doses create a pro-inflammatory environment in inexperienced horses. In conclusion, ß2-adrenoceptor stimulation leads to a biphasic response. In addition, the immune cells are more sensitive to drug abuse in inexperienced individuals under physical training.


Assuntos
Agonistas de Receptores Adrenérgicos beta 2/farmacologia , Clembuterol/farmacologia , Cavalos/sangue , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Proliferação de Células/efeitos dos fármacos , Citocinas/biossíntese , Feminino , Leucócitos Mononucleares/efeitos dos fármacos , Masculino , Monócitos/citologia , Monócitos/efeitos dos fármacos , Fenótipo
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