Lactacidemia e concentrações séricas de aspartato aminotransferase e creatinoquinase em equinos da raça Quarto de Milha usados em provas de laço em dupla

How Much Energy Vaquejada Horses Spend in a Field Simulation Test?

Vaquejada is a high-intensity and short-duration exercise in which helper horses (HH) are responsible to keep a bull running in a line while pull horses (PH) work to put the bull down after 100 m of running. The purpose of this study was to quantify and compare energy expenditures (EE), transport costs (COT) and metabolic energy requirements (Pmet) of horses used in Vaquejada. Thus, eight Quarter Horses, in randomly formed pairs, performed a vaquejada simulation test (VST), which consisted of three races on a sand track (130-150 m), with a 5-min interval between them. All horses used an integrated heart rate (HR) and GPS monitoring system (V800, Polar Electro) and, from these data, EE, COT and Pmet were calculated using the formulas: EE (J/kg/min) = 0.0566 × HR^1.9955, COT = (HR-35)/kg/m × 10³ and Pmet = (HR-35)/min/kg. Blood samples were collected for lactate analysis at rest, immediately after the first, second and third race and after 30 min of recovery. Data obtained were submitted to one-way ANOVA and Tukey tests (p ≤ 0.05). In VST, HH had higher EE and higher HR at trot; while PH presented higher EE and HR at canter. Finally, considering total VST, PH had higher EE and COT, while HH had higher Pmet. Lactate was higher in PH. Despite practicing the same sport, PH and HH should be considered distinct athletes, and these must be considered to set up appropriate physical and nutritional programs, which will lead to better performance and guarantees of well-being.

Is There an Ideal Rest Interval Between Races During Vaquejada in Which It Would Be Possible to Associate Best Performance and Welfare?

Vaquejada is an important Brazilian equine discipline. Understanding physiological adaptations of these athletes is crucial to improve properly performance, guaranteeing welfare. The objective of this study was to evaluate the influence of three vaquejada simulation tests (VST) on physiological parameters of horses and standardize a possible rest interval between races. Ten clinically healthy Quarter horses, 8.9 ± 4.3 year-old and 441.3 ± 25.0 kg, executed three VST, 5 days apart from each other. Vaquejada simulation tests consisted of two horses, a puller, and a helper, running with a bull on a soft sand track in which they must put the bull down. On M1, they ran three times with a 5-min rest between races; on M2, with a 10-min rest; and M3, with a 15-min rest. Clinical evaluation and blood sampling were made in all VST, before (T0), immediately after first run (T1), second run (T2), third run (T3) and at 30 minutes (T4), and 4 hours (T5) of recovery. Variables were statistically analyzed with a bifactorial comparison (P < .05). Exercise increased heart rate (HR), respiratory rate, body temperature (BT), lactate, triglycerides, packed cell volume, RBC, and hemoglobin concentration, with higher values in pull horses due to a more intense exercise. With 15-min of rest interval, helper horses showed lower values of glucose, aspartate aminotransferase, creatine kinase, BT, and higher values of triglycerides, also working at the same speed and distance with a lower HRmax and HRmed. Pull and helper horses had shown modifications of biomarkers. Furthermore, 15-min rest interval between races improved performance of helper horses as they used properly energy sources and cardiovascular function, respecting precepts of welfare.

Parâmetros fisiológicos e bioquímicos de equinos em treinamento de três tambores: pós-condicionamento, pós-percurso e pós-descanso

RESUMO Foram avaliados parâmetros fisiológicos e bioquímicos em equinos Quarto de Milha durante treinamento de três tambores, antes do condicionamento (T0), após o condicionamento (T1), após um percurso (T2), após descanso do percurso, por 20 minutos (T3) e após descanso do percurso, por 40 minutos (T4). Os parâmetros físicos avaliados foram: frequência cardíaca (FC), frequência respiratória (FR), temperatura retal (TR) e tempo de enchimento capilar (TEC); e os bioquímicos: sódio, potássio, cloreto, cálcio total, ureia, creatinina, osmolaridade, creatinaquinase, aspartato transaminase, proteínas totais (PT), glicose e lactato. A FC, a FR e a TR aumentaram após o percurso (T2), mas foram recompostas após 40 minutos de descanso. A concentração do lactato pouco aumentou após o condicionamento, mas altas concentrações ocorreram após o percurso (T2), e embora ele tenha diminuído após 20 (T3) e 40 minutos (T4) do percurso, ainda permaneceu acima dos limites normais. Nos demais parâmetros, não houve variações significativas. Concluiu-se que, ao final de um percurso de três tambores, o exercício sob máxima intensidade não ocasionou variações bioquímicas significativas nos equinos, exceto para o lactato, pois gerou uma hiperlactatemia que não foi restaurada até 40 minutos de descanso pós-percurso, mesmo com os parâmetros físicos já recompostos do esforço.

Limiar anaeróbico (V4) e frequência cardíaca de cavalos Crioulos condicionados para prova funcional

Determinou-se o limiar anaeróbico (V4) de 23 cavalos Crioulos hígidos em treinamento. Os animais selecionados foram submetidos a testes de desempenho, composto por três etapas de velocidade progressiva de 6m/s, 8m/s e 10m/s, com duração de cinco minutos cada etapa, até que fosse atingida a concentração de 4mmol/dL de lactato sanguíneo. As concentrações de lactato sanguíneo elevaram-se a partir da velocidade de exercício de 6,0m/s, sendo que 20 animais (90%) atingiram 4mmol/L de lactato na velocidade entre 6 - 8m/s, com média de frequência cardíaca que variou de 121 a 140bpm. Concluiu-se que a V4 do cavalo Crioulo está entre as velocidades de 6 - 8m/s e a frequência cardíaca entre 121 - 140bpm.