Hélio Cordeiro Manso Filho

Effect of orange peel and black tea extracts on markers of performance and cytokine markers of inflammation in horses

This study tested the hypothesis that orange peel (O) and decaffeinated black tea (T) extracts would alter markers of exercise performance as well as exercise-induced mRNA expression for the inflammatory cytokines IL-6, TNFalpha and IFN-gamma. Nine healthy, unfit Standardbred mares (age: 10 ^ 4years, ,450kg) were assigned to three treatment groups in a randomized crossover design where each horse was administered one of the following; placebo (O; 2l water), black tea extract in water (T; 2l) or orange peel extract in water (W; 2l), via a nasogastric tube. One hour later the horses completed an incremental graded exercise test (GXT) on a treadmill at a fixed 6% grade with measurements and blood samples obtained at rest, at the end of each 1min step of the GXT and at 2 and 5min post-GXT. An additional set of blood samples for Polymerase Chain Reaction (PCR) measurements of mRNA was obtained before exercise and at 5 and 30min and 1, 2, 4 and 24h post-GXT. The GXTs were conducted between 0700 and 1200h not less than 7days apart. There were no differences (P . 0.05) in VO2max, respiratory exchange ratio, run time, velocity at VO2max, core body temperature, haematocrit, creatine kinase (CK), plasma lactate concentrations, HR, right ventricular pressure (RVP) or pulmonary artery pressure (PAP) across treatments. A major finding was that orange peel extract significantly reduced post-exercise VO2 recovery time (W ¼ 112 ^ 7, O ¼ 86 ^ 6, and T ¼ 120 ^ 11s). There was a significant difference in plasma total protein concentration (TP) in the O runs compared with water and T. TNF-alpha mRNA expression was lower in the T runs compared with water and O trials. IFN-gamma mRNA expression levels appeared to be lower in both the Tand O extract runs compared with the water trials. The mRNA expression of IL-6 was unaltered across treatment groups. These data suggest that orange peel and black tea extracts may modulate the cytokine responses to intense exercise. Orange peel extract reduced post-exercise recovery time and may potentially enhance the ability of horses to perform subsequent bouts of high-intensity exercise.

Distribution of glutamine synthetase and an inverse relationship between glutamine synthetase expression and intramuscular glutamine concentration in the horse

Glutamine plays important roles in the interorgan transport of nitrogen, carbon and energy but little is known about glutamine metabolism in the horse. In this study we determined the tissue distribution of glutamine synthetase expression in three Standardbred mares. Expression of glutamine synthetase was highest in kidney and mammary gland, and relatively high in liver and adipose tissue. Expression was lower in gluteus muscle, thymus, colon and lung, and much lower in small intestine, pancreas and uterus. The pattern of glutamine synthetase expression in the horse is similar to that of other herbivores and it is likely that skeletal muscle, liver, adipose tissue and lungs are the major sites of net glutamine synthesis in this species. Expression did not differ between adipose tissue depots but did vary between different muscles. Expression was highest in gluteus and semimembranous muscles and much lower in diaphragm and heart muscles. The concentration of intramuscular free glutamine was inversely correlated with expression of glutamine synthetase (r=-0.81, p=0.0017). The concentration of free glutamine was much higher in heart muscle (21.6+/-0.9 micromol/g wet wt) than in gluteus muscle (4.19+0.33 micromol/g wet wt), which may indicate novel functions and/or regulatory mechanisms for glutamine in the equine heart.

Clinical and laboratory assessment of Mangalarga Marchador horses submitted to marcha exercise

José Dantas Ribeiro Filho1*, Rinaldo Batista Viana2, Hélio Cordeiro Manso Filho3, Waleska de Melo Ferreira Dantas4, Micheline Ozana da Silva5, Pedro Ancelmo Nunes Ermita4, Samuel Rodrigues Alves6, Lorena Chaves Monteiro6 & Caio Monteiro Costa6 1 Veterinarian, DSc, Professor. Departamento de Veterinária – DVT, Centro de Ciências Biológicas e da Saúde – CCB, Universidade Federal de Viçosa – UFV, Viçosa, MG, Brasil 2 Veterinarian, DSc, Professor. Instituto da Saúde e Produção Animal ISPA, Universidade Federal Rural da Amazônia UFRA, Belém, PA, Brasil 3 Veterinarian, PhD, Professor. Departamento de ZootecniaDZO, Núcleo de Pesquisa Equina NPE, Universidade Federal Rural do Pernambuco, Recife, PE, Brasil 4 Veterinarians, DSc. Departamento de Veterinária – DVT, Centro de Ciências Biológicas e da Saúde – CCB, Universidade Federal de Viçosa – UFV, Viçosa, MG, Brasil 5 Physiotherapist, DSc. Departamento de Veterinária – DVT, Centro de Ciências Biológicas e da Saúde – CCB, Universidade Federal de Viçosa – UFV, Viçosa, MG, Brasil 6 Veterinarians, MSc. Departamento de Veterinária – DVT, Centro de Ciências Biológicas e da Saúde – CCB, Universidade Federal de Viçosa – UFV, Viçosa, MG, Brasil How to cite: Ribeiro Filho, J. D., Viana, R. B., Manso Filho, H. C., Dantas, W. M. F., Silva, M. O., Ermita, P. A. N., Alves, S. R., Monteiro, L. C., & Costa, C. M. (2018). Clinical and laboratory assessment of Mangalarga Marchador horses submitted to marcha exercise. Brazilian Journal of Veterinary Medicine, 40, e47418. doi: 10.29374/2527-2179.bjvm47418

Maternal and Fetal Heart Rates During Exercise in Horses

This study tested two hypotheses. First, that moderate exercise would alter maternal and foetal heart rate (HR) in the horse. Second, that pregnancy would alter the HR, plasma cortisol and plasma lactate response to moderate exercise in mares. Six unfit, pregnant Standardbred mares (6–19 years) underwent two incremental graded exercise tests (GXT). The first GXT was performed at approximately 9 months of gestation, which represents c. 80% of the total pregnancy time, and the second GXT at approximately 6 months post-parturition. During the GXT, mares ran on a treadmill up a fixed 6% incline completing three 1 min steps at velocities of 4, 6 and 7 m s. Maternal HR was obtained via both electrocardiograph (ECG) and the ventricular waveform obtained from a micromanometer catheter. Data were recorded at rest, at 4, 6 and 7 m s of the GXT and at 0, 1, 2, 3, 4 and 5 min post-GXT. Foetal HR rate was measured via ECG before, immediately after and at 1, 2, 3, 4 and 5 min post-GXT. Radioimmunoassay (RIA) kits were used to measure plasma cortisol concentration in samples collected before the GXT, immediately after exercise and after 5 min of recovery. Plasma lactate concentrations (LA) were measured at rest, at 4, 6 and 7 m s and at 5 min post-GXT. Plasma cortisol concentrations were measured using RIA and the samples collected at rest, immediately after and at 5 min post-GXT. Exercise caused no change (P . 0.05) in foetal HR. Maternal HR, plasma LA and plasma cortisol concentration were greater (P , 0.05) during the post-parturient GXT compared with the pre-parturition GXT. Body weight (mean ^ SE) was lower after parturition (570 ^ 20 vs. 505 ^ 22 kg; P , 0.05). Consequentially, there were differences (P , 0.05) in work rate (watts) at each step of the GXT (1557 ^ 53 vs. 1381 ^ 60; 2339 ^ 80 vs. 2071 ^ 90; and 2571 ^ 121 vs. 2416 ^ 105 W). These data suggest that mares benefit from greater cardiovascular efficiency during pregnancy. Additionally, the lack of a change in foetal HR suggests that the unborn foal is not stressed during moderate maternal exercise.