Field-training in young two-year-old thoroughbreds: investigating cardiorespiratory adaptations and the presence of exercise induced pulmonary hemorrhage.
BMC Vet Res
; 20(1): 159, 2024 Apr 26.
Article
em En
| MEDLINE
| ID: mdl-38671428
ABSTRACT
BACKGROUND:
Comparatively little is known regarding the initial cardiorespiratory response of young racehorses to training. The objectives were to compare physiological parameters before and after introductory training and determine whether young Thoroughbreds show endoscopic signs of exercise-induced pulmonary hemorrhage (EIPH). Ten Thoroughbreds (20-23 months) underwent 12-weeks of introductory training, including weekly speed sessions. Two 600 m high-speed exercise tests (HSET) were performed following weeks 4 and 12 while wearing a validated ergospirometry facemask. Peak oxygen consumption (VÌO2pk) and ventilatory parameters (tidal volume, VT; peak inspiratory and expiratory flow, PkVÌI, PkVÌE; respiratory frequency, Rf; minute ventilation, VÌE) were measured. The ventilatory equivalent of oxygen (VÌE/VÌO2) and the aerobic and anaerobic contributions to energy production were calculated. Maximal heart rate (HRmax) and HR at maximal speed (HRVmax) were determined. Post-exercise hematocrit, plasma ammonia and blood lactate were measured. Evidence of EIPH was investigated via tracheobronchoscopy post-exercise. Results were compared (paired t-test, P < 0.05).RESULTS:
Horses were faster following training (P < 0.001) and VÌO2pk increased 28 ml/(kg total mass.min) (28 ± 16%; P < 0.001). Ventilatory (VÌE, P = 0.0015; Rf, P < 0.001; PkVÌI, P < 0.001; PkVÌE, P < 0.001) and cardiovascular parameters (HRmax, P = 0.03; HRVmax, P = 0.04) increased. The increase in VÌE was due to greater Rf, but not VT. VÌE/VÌO2 was lower (26 ± 3.6 vs 23 ± 3.7; P = 0.02), indicating improved ventilatory efficiency. Anaerobic contribution to total energy production increased from 15.6 ± 6.1% to 18.5 ± 6.3% (P = 0.02). Post-exercise hematocrit (P < 0.001), plasma ammonia (P = 0.03) and blood lactate (P = 0.001) increased following training. Horses showed no signs of EIPH.CONCLUSIONS:
Young two-year-old Thoroughbreds responded well to introductory training without developing tracheobronchoscopic evidence of EIPH.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Consumo de Oxigênio
/
Condicionamento Físico Animal
/
Hemorragia
Limite:
Animals
Idioma:
En
Revista:
BMC Vet Res
Assunto da revista:
MEDICINA VETERINARIA
Ano de publicação:
2024
Tipo de documento:
Article
País de afiliação:
Canadá