Factors influencing variation in locomotor-respiratory coupling in standardbred trotters in the field.

Reasons For Performing Study: A close relationship between limb and respiratory rhythms has been shown in clinically healthy galloping horses due to mechanical constraints in the thoracic region. This synchronisation leads to a 1/1 ratio between stride frequency (SF) and respiratory frequency (RF) during galloping. Very little is known about locomotor-respiratory coupling (LRC) during fast trot.

Harnessed vs. mounted standardbreds on the track: changes in gait and physiological variables.

Reasons For Performing Study: It has become apparent through analysis of elite races over the past 20 years that mounted races are always slower than harnessed races when performed by the same horses over the same distances on the same tracks.

Objectives: To investigate and compare physiological and gait variables in mounted and harnessed activities in trotters.

Methods: Ten trotters were taken at random in 2 standardised field exercise tests one week apart: a harnessed and a mounted test with standardised weight jockeys and drivers.

Optimal active recovery intensity in standardbreds after submaximal work.

Reasons For Performing Study: A retrospective study concerning spontaneous active recovery intensity, i.e. at a freely chosen speed, after a submaximal exercise in trotters showed that the mean intensity demanded by trainers corresponds to 40-50% of maximal heart rate (max HR; unpublished data).

Body composition in young standardbreds in training: relationships to body condition score, physiological and locomotor variables during exercise.

Reasons For Performing Study: Body composition is an essential factor in athletic performance of human sprinters and long distance runners. However, in horses, many questions remain concerning relationships between body composition and performance in the different equine activities.

Objectives: To determine relationships between body composition, body score, physiological and locomotor variables in a population of young Standardbreds in training.

Relationships between physiological variables and race performance in French standardbred trotters.

The relationships between V4 (the velocity for a blood lactate concentration of 4 mmol/litre) and V200 (the velocity for a heart rate of 200 bpm) and the performance indices of 223 healthy French trotters were analysed. They were divided into four age groups of three, four, five and six years and over, and into three performance groups (good, intermediate and poor performers) defined by the index of trot (ITR), an annual index of performance calculated by the national stud. V4 and V200 were assessed during the performance of a three-step standardised field exercise test, and four performance indexes (ITR, earnings, best time and the number of starts) were calculated for each group.

Reproducibility of a locomotor test for trotter horses.

Locomotion analysis is increasingly used to assess the gait of horses in the selection and training of equine athletes. We have developed a specific locomotor test for fast trotting harnessed horses that uses an accelerometric device. We describe here the reproducibility of the locomotor test and the validation of its use to analyse trotters on the racetrack.

[Structure-activity relationship of semi-synthetic derivatives of the PIA component of pristinamycin].

Pristinamycin is a naturally occurring streptogramin made up of 2 groups of synergistic components (PI and PII). Because these components are not water soluble, use of pristinamycin has up till now been confined to the oral route. Water soluble semisynthetic derivatives of the PIA component, appropriate for parenteral use, have lately been developed.