Race Season Research Articles

The influence of health status on the changes of gut microbiota and performance of racing pigeons

During the race season of racing pigeons, the demands on their care, zoohygienic conditions, balanced feeding and maintaining an optimal state of health increase. Any deviation in the mentioned factors causes a stressful situation associated with the changes in the bacterial representation in the digestive tract, weakens the individual´s state of health and thus reduces his performance. The work aimed to monitor the health status of racing pigeons and evaluate their performance during one racing season. From 60 pigeons, swabs from the cloaca and crop were taken at regular intervals at the beginning, in the middle and at the end of the race season with a focus on monitoring the representation of the intestinal microflora and the most common diseases. The pigeons were also clinically examined with subsequent sampling for monitoring coccidiosis, trichomonosis and respiratory syndrom during the individual phases of the race season. The total count of bacteria (TCB) in both the cloaca and the crop did not show any significant variation in their abundance throughout the entire racing season. On the other hand, with increasing stress and the occurrence of diseases, the coliform bacteria (CB) in the cloaca and crop was increased in the end of the racing season. Of the identified bacteria Ent. columbae, E. coli, Ent. faecium, Ent. gallinarum a S. intermedius were most frequently represented in swabs from the cloaca. As in the cloaca, the swabs from the crop were most frequently represented by Ent. columbae a E. coli together with lactobacilli and Ent. gallinarum. At the end of race season, E. coli, Ent. faecium, Ent. columbae and staphylococci were significantly represented in the cloaca and in the crop Ent. columbae, E. coli, Ent. gallinarum together with staphylococci again. By comparing the prevalence of Eimeria spp. and Trichomonas spp. before, during and at the end of the race season were noticed their increased occurrence at the end of the season. From the race placements, we found that in pigeons in which the prevalence of opportunistic pathogens Staphylococcus spp. a Ent. gallinarum from swabs of the cloaca and crop at the lowest level together with the occurrence of Eimeria spp., they achieved constant results the entire race season and also achieved the best points position.

Comparison of Reported Fatalities, Falls and Injuries in Thoroughbred Horse Jumps and Flat Races in the 2022 and 2023 Jumps Race Seasons in Victoria, Australia.

Jumps racing is a form of Thoroughbred horse racing that involves hurdles and steeples and typically longer distances, and heavier weights compared with flat racing, which does not incorporate obstacles. In Australia, jumps racing is carried out only in Victoria, one of eight states and territories. The continuation of jumps racing is contentious due to the higher risk of fatalities, falls and injuries for horses, compared with flat racing. While measures have been introduced by the industry to improve the safety of riders and horses, the rates of fatalities, falls and injuries in horses participating in jumps races have not been collectively reported in Australia since the 2012 to 2014 race seasons. Although information on individual horse fatalities, falls and injuries is published by Racing Victoria in Stewards' Reports, the data are not aggregated, and so cannot readily be used to assess trends or evaluate the efficacy of safety measures introduced by the industry. The aim of this study was to determine the fatality, fall and injury rates for horses participating in hurdle and steeplechase races in Victoria in the 2022 and 2023 Thoroughbred horse jumps racing seasons compared with horses participating in flat races at the same race meets. Data on horse fatalities, falls and injuries were extracted from the published Racing Victoria race results and Stewards' Reports for the jumps races (n = 150) and corresponding flat races (n = 157) held at the 38 jumps race meets in Victoria in 2022 and 2023. Overall, horse fatalities, falls and injuries occurred at higher rates in jumps races compared with flat races during the study period. The rate of horse fatalities in jumps races was 3.3 per 1000 starts, with no fatalities in flat races. The rate of horse falls in hurdle races was 24 per 1000 starts and 41.6 per 1000 starts in steeplechase races, comparable with rates previously reported in the 2012 to 2014 seasons. There were no falls in flat races. Horse injuries occurred at a rate of 68.9 per 1000 starts in jumps races compared with 18.8 per 1000 starts in flat races. In hurdle and steeplechase races, veterinary clearance being required following horse injury was 5.4 times (OR 5.4, 95% CI 2.8-10.2) and 7.2 times (OR 7.2, 95% CI 3.3-15.6) more likely, respectively, compared with flat races. The risk of trauma was 4 times more likely in hurdle and steeplechase races (OR 4.8, 95% CI 1.7-13.3 and OR 4.1, 95% CI 1.2-13.4, respectively) and the risk of lameness was increased by 2.5 times in hurdles (OR 2.5, 95% CI 1.2-5.2) and 5.1 times in steeplechase races (OR 5.1, 95% CI 2.3-11.5), compared with flat races. These findings support concerns about the welfare of horses involved in jumps racing and of the need for further safety measures to reduce these risks.

Optimizing Logistics in Formula 1: Simplifying Complex Race Season Schedules

This article examines the global logistics challenges of the Formula 1 season. Throughout the season, F1 needs to hold races in 21 different locations worldwide, and each race requires hundreds of people working together behind the scenes to ensure that everything is ready within the specified time. As a highly challenging sporting event, F1s ten teams must configure optimal facilities in 21 temporary headquarters and rely on partners such as DHL to transport over one thousand tons of equipment which worth millions of dollars to the competition venues. Shipping equipment and racing parts involve complex logistics across continents, with risks of delays. Solutions include prioritizing tracking and scheduling races in adjacent geographic areas to reduce transportation costs and risks. The article also explores ways to resolve logistical complexities in the F1 season schedule, including considering trucks as the primary mode of transport, concentrating races in the same geographical area and rearranging the season calendar to reduce transport costs and enable sustainable racing operations.

Racehorse welfare across a training season.

Racehorse welfare is gaining increasing public attention, however scientific evidence in this area is lacking. In order to develop a better understanding of racehorse welfare, it must be measured and monitored. This is the first study to assess racehorse welfare using scientific objective methods across a training season. The aim of this study was threefold, firstly to investigate welfare measures which could be used in the first welfare assessment protocol for racehorses. Secondly, to understand the effect that a racing and training season had on individual racehorses and thirdly to identify risk factors for both good and poor welfare. Thirteen racehorse training yards were visited at the beginning and the peak of the racing season in England. Behavioral observations along with individual environmental and animal-based welfare measures were carried out on 353 horses in 13 training yards selected for variability. In our sample the horses were generally in good physical health: 94% of horses recorded as an ideal body condition score, no horses had signs of hoof neglect and 77.7% had no nasal discharge. The overall prevalence of external Mouth Corner Lesions was 12.9% and was significantly higher for Flat racing than Jump racing horses. The majority of horses (67.5%) showed positive horse human interactions. When stabled 54.1% horses had physical social contact and nasal discharge was not associated with increased physical contact. The training season significantly affected Human Reactivity Tests, Horse Grimace Scale scores and time spent resting and feeding. A total of 14.5% of horses displayed stereotypic behavior on at least two occasions. Horses with windows in their stables spent more time surveying their surroundings. Overall, in this population of racehorses, horses spent around a third of their daytime feeding (33.7%) followed by time spent standing resting (22.6%). The welfare assessment protocol used in this study is suitable for use in industry to collect welfare data on racehorses.

Longitudinal Outcomes of Cumulative Impact Exposure on Oculomotor Functioning in Professional Motorsport Drivers

Professional motorsport drivers are regularly exposed to biomechanical forces comparable with those experienced by contact and collision sport athletes, and little is known about the potential short-term and long-term neurologic sequelae. To determine whether cumulative impact exposure is associated with oculomotor functioning in motorsport drivers from the INDYCAR professional open-wheel automobile racing series. This is a longitudinal retrospective cohort study conducted across 3 racing seasons (2017-2019). Statistical analyses were conducted in November 2021. Data were retrieved from a secondary care setting associated with the INDYCAR series. INDYCAR series drivers who participated in 3 professional level racing seasons and were involved in at least 1 contact incident (ie, crash) in 2 of the 3 seasons were included in the study. Cumulative acceleration and deceleration forces and total contact incidents (ie, crashes) measured via accident data recorder third generation chassis and ear accelerometers. Postseries oculomotor performance, including predictive saccades, vergence smooth pursuit, and optokinetic nystagmus, was measured annually with a head-mounted, clinical eye tracking system (Neurolign Dx 100). Thirteen drivers (mean [SD] age, 29.36 [7.82] years; all men) sustained median resultant acceleration forces of 38.15 g (observed range, 12.01-93.05 g; 95% CI, 30.62-65.81 g) across 81 crashes. A 2-way multivariate analysis of variance did not reveal a statistically significant association between ear and chassis average resultant g forces, total number of contact incidents, and racing season assessed (F9,12 = 0.955; P = .54; Wilks Λ = 0.44). In this cohort study of professional drivers from the INDYCAR series, there were no statistically significant associations among cumulative impact exposure, racing season assessed, and oculomotor performance. Longitudinal studies across racing seasons using multidimensional examination modalities (eg, neurocognitive testing, advanced imaging, biomarkers, and physical examination) are critical to understand potential neurological and neurobehavioral sequelae and long-term consequences of cumulative impact exposure.

Changes Of Bone Metabolism Markers In Japanese Male Long Distance Runners During In-season

Stress fracture is one of the most common overuse injuries in runners and there are many risk factors that predispose to this injury. Previous studies have focused on bone metabolism and the correlation between stress fractures and bone metabolism has been reported. However, most studies are on female athletes, and little is known on male athletes. Moreover, long-term bone metabolic process in athletes is unknown. PURPOSE: To investigate changes bone metabolism markers in male long distance runners during in-season METHODS: Twenty-five male long distance runners participated in this study, and total of 11 athletes were qualified for analysis (24 ± 4.3 yrs, 170.4 ± 5.0 cm, 55.9 ± 3.7 kg) after excluding those who were injured and/or were not able to run more than 200 km per month. Blood samples were collected from 9 am to 11 am during pre-season (PRs), post-track season (PTs), and road-race season(RRs). Athletes were instructed to refrain from training prior to blood collection. To assess bone metabolism bone-specific alkaline phosphatase(BAP) and tartrate-resistant acid phosphatase-5b(TRACP-5b) were measured. In addition, athletes reported their monthly training volume of one month prior the first measurement. Changes of bone metabolic markers were assessed by one-way ANOVA with repeated measures and correlations between training volume and both markers were made using Spearman’s rank correlation coefficient. RESULTS: BAP in PTs (14.98 ± 3.11 vs. 16.62 ± 3.76 p = 0.004) and RRs (14.85 ± 3.68 vs. 16.62 ± 3.76 p = 0.004) were significantly lower than that of PRs. There were no statistically significant changes in TRACP-5b. Moreover, there were not any correlations between monthly training volume and both bone metabolism markers. CONCLUSIONS: We found that BAP lower than PRs from the latter half of track season to the road race season.

INFLUENCE OF TRIATHLON ON AORTIC STIFFNESS: THE ATLAS STUDY

Objective: Arterial stiffness is a strong predictor of future cardiovascular events and all-cause mortality. Endurance exercise is efficacious in reducing arterial stiffness. Triathlon, i.e., swimming, cycling and running over long to ultra-long distances in a row, is one of the most demanding endurance sports disciplines inducing major cardiovascular adaptations. However, acute and long-term effects of triathlon on arterial stiffness are still unknown. Therefore, we investigated arterial stiffness modification during a triathlon season. Design and method: The ATLAS study is a prospective interventional controlled and age matched study. We included thirty-four 19–39-years-old male long-distance triathletes (Tri) and twenty-nine healthy sex- and age-matched volunteers who were insufficiently active (Ctrl) according to World Health Organization recommendations. All participants attended three visits (V1, V2, V3) each separated by five months intervals, spread over the course of the race season. Each visit included an aortic stiffness evaluation by applanation tonometry. Results: After a race season, aortic pulse wave velocity (aoPWV) was significantly lower in the triathletes group (aoPWV tri = 6,11 ± 0,95 versus aoPWV ctrl = 7,17 ± 1,24 m/s with p = 0,0009). Triathletes had central systolic blood pressure (cSBP) and central pulse pressure (cPP) significantly higher than in control group (respectively, cSBP tri = 122,60 ± 11,43 versus cSBP ctrl = 116,64 ± 6,88 mmHg with p = 0,01, and cPP tri = 54,18 ± 10,04 versus cPP ctrl = 45, 44 ± 7,55 mmHg with p = 0,0002). Triathlon was correlated with a statistically significant positive impact on subendocardial viability ratio (SEVR) (SEVR tri = 162,89 ± 26,55 versus SEVR ctrl = 133,22 ± 26,99 with p = 0,00009). No statistically significant longitudinal variation of aoPWV was observed in triathletes during the race season. Conclusions: These results suggest that triathlon has persistent beneficial effects on arterial stiffness, and even on myocardial perfusion. This improvement cardiovascular health for triathletes seems to reach its peak at the end of the sportive season.

Does Wim Hof Method Improve Breathing Economy during Exercise?

(1) Background: Breathing economy during endurance sports plays a major role in performance. Poor breathing economy is mainly characterized by excessive breathing frequency (BF) and low tidal volume (VT) due to shallow breathing. The purpose of this study was to evaluate whether a 4 week intervention based on the Wim Hof breathing method (WHBM) would improve breathing economy during exercise in adolescent runners. (2) Methods: 19 adolescent (16.6 ± 1.53 years) middle- and long-distance runners (11 boys and 8 girls) participated in the study. Participants were randomly divided into experimental (n = 11) and control groups (n = 8). The study was set in the transition period between competitive race seasons and both groups had a similar training program in terms of running volume and intensity over the course of the study. The experimental group performed breathing exercises every day (~20 min/day) for 4 weeks. The control group did not perform any kind of breathing exercise. The breathing exercises consisted of three sets of controlled hyperventilation and consecutive maximum breath holds. Before and after the intervention, participants performed incremental cycle ergometer testing sessions consisting of two minute stages at 1, 2, 3, and 4 W·kg−1 with breath-by-breath metabolic analysis. During the testing sessions, BF, VT, and minute ventilation (VE) were assessed and compared. (3) Results: There were no statistically significant differences (p > 0.05) in BF, VT, or VE between experimental and control groups before or after the intervention. A nonsignificant small-to-large effect for an increase in VE and BF in both groups following the 4 week intervention period was observed, possibly due to a reduction in training volume and intensity owing to the down period between competitive seasons. (4) Conclusions: The 4 week intervention of WHBM did not appear to alter parameters of breathing economy during a maximal graded exercise test in adolescent runners.

DETERMINATION OF RACE PERFORMANCE’S FACTORS OF ARABIAN THOROUGHBRED TUNISIAN HORSES AND THE IMPACT OF INTRODUCTION OF OCCIDENTAL THOROUGHBRED HORSES INTUNISIA

The aim of the study is to investigate the effects of age, sex, running distance and origin of horse on racing speed for Thoroughbred Arabian horse in Tunisia. Although the occidental type is known to be more successful in racing than the Tunisian type, we undertook this study to try to confirm or deny this supremacy for a sample of racehorses born in Tunisia from occidental father. A total of 333 racing records were considered for race performance. The effects of environmental factors on (sex, age, father’s origin, race distance, number of race seasons) race performance were analyzed using the least-squares method(LSM).The racehorses studied were all Arabian Thoroughbred horses in operation at the racecourse of Ksar Said from 2010 to 2020. They are 180 horses, 90 horses born of a Tunisian father, and 90 horses born in Tunisia ofthe occidentalfather. These horses are the best and most successful in their category. The study revealed that the gender and age effectswere statistically insignificant onracingperformance. Race performance was significantly influenced by the distance and the origin of the father which affirms the improving role of the occidentalhorse in the Tunisian population.

Heart rate variability before and after 14 weeks of training in Thoroughbred horses and Standardbred trotters with different training experience.

Changes in heart rate and heart rate variabilty (HRV) were investigated in untrained (UT; starting their first racing season) and detrained (DT; with 1-3 years of race experience) racehorses before and after 14-week conventional training. HRV was measured at rest over 1 h between 9:00 and 10:00 AM on the usual rest day of the horses. The smallest worthwhile change (SWC) rate was calculated for all HRV parameters. UT horses had significantly higher heart rate compared to DT (P<0.001). There were no gender- or training-related differences in heart rate. The root-mean-square of successive differences (rMSSD) in the consecutive inter-beat-intervals obtained after the 14-week training period was lower compared to pre-training rMSSD (P<0.001). The rMSSD was not influenced by breed, age or gender. In DT horses, there was a significant decrease in the high frequency (HF) component of HRV (P≤0.05) as the result of the 14-week training. These results may reflect saturation of high-frequency oscillations of inter-beat intervals rather than the reduction in parasympathetic influence on the heart. The HF did not differ significantly between the two measurements in UT horses; however, 16.6% of the animals showed a decrease in HF below SWC (P≤0.05). This supports the likelihood of parasympathetic saturation. Although no significant decrease in heart rate was found for the post-training, 30.0% of DT and 58.3% of UT horses still showed a decrease in heart rate below the SWC. Also by individual examination, it was also visible that despite significant post-training decrease in rMSSD, 1 (4.6%) DT and 2 (6.7%) UT horses reached SWC increase in rMMSD. In the case of these horses, the possibility of maladaptation should be considered. The present results indicate that similar to as found in human athletes, cardiac ANS status of racehorses also changes during the physiological adaptation to training. To explore more precise links between HRV and training effectiveness in horses, a more frequent recording would be necessary. Detailed analysis of HRV parameters based on SWC will be able to highlight the importance of fitness evaluation at individual level.

Factors associated with racing performance and career duration for Victorian-born Thoroughbreds.

The number of horses leaving the Australian Thoroughbred (TB) racing industry each year is of concern to animal welfare advocates, public and regulators. A horse's previous athletic performance is a significant driver of retirement from racing. Racehorse performance can be measured in terms of the total number of starts, duration of racing and prize money earned. This study investigated Australian racing records for the 2005 and 2010 Victorian TB foal crops to identify factors associated with total number of starts, racing career duration, prize money earned and age of last race start-up to the 10-year-old racing season. Racing Australia registered 4,577 TB horses born in Victoria in 2005 (n=2,506) and 2010 (n=2,071) that raced in Australia. Horses that started racing at 2-years of age had fewer race starts in their first racing season but an increased total number of starts, prize money and duration of racing. The median age of last start (LS) was five (Q1 4; Q3 7) years. Horses that had won a race, had a maximum handicap rating of 61 or above and those racing over distances of more than 2,400 m had an increased racing career duration and an age of last race start greater than 6-years of age. Horses participating in jumps races (n=63) had the longest careers and older age of LS. These horses were more likely to have had a handicap rating over 80 and were just as likely to start their racing careers as 2-years-olds.

DETERMINATION OF RACE PERFORMANCE’S FACTORS OF ARABIAN PUREBRED TUNISIAN HORSES AND THE IMPACT OF INTRODUCTION OF OCCIDENTAL PUREBRED HORSES INTUNISIA

The aim of the study is to investigate the effects of age, sex, running distance and origin of horse on racing speed for Purebred Arabian horse in Tunisia. Although the occidental type is known to be more successful in racing than the Tunisian type, we undertook this study to try to confirm or deny this supremacy for a sample of racehorses born in Tunisia from occidental father. A total of 333 racing records were considered for race performance. The effects of environmental factors on (sex, age, father’s origin, race distance, number of race seasons) race performance were analyzed using the least-squares method(LSM).The racehorses studied were all Arabian Purebred horses in operation at the racecourse of Ksar Said from 2010 to 2020. They are 180 horses, 90 horses born of a Tunisian father, and 90 horses born in Tunisia ofthe occidentalfather. These horses are the best and most successful in their category. The study revealed that the gender and age effectswere statistically insignificant onracingperformance. Race performance was significantly influenced by the distance and the origin of the father which affirms the improving role of the occidentalhorse in the Tunisian population.

A Novel mHealth Monitoring System during Cycling in Elite Athletes.

Background: Cycling is a very demanding physical activity that may create various health disorders during an athlete’s career. Recently, smart mobile and wearable technologies have been used to monitor physiological responses and possible disturbances during physical activity. Thus, the application of mHealth methods in sports poses a challenge today. This study used a novel mobile-Health method to monitor athletes’ physiological responses and to detect health disorders early during cycling in elite athletes. Methods: Sixteen high-level cyclists participated in this study, which included a series of measurements in the laboratory; health and performance assessments; and then application in the field of mHealth monitoring in two training seasons, at the beginning of their training period and in the race season. A field monitoring test took place during 30 min of uphill cycling with the participant’s heart rate at the ventilatory threshold. During monitoring periods, heart rate, oxygen saturation, respiratory rate, and electrocardiogram were monitored via the mHealth system. Moreover, the SpO2 was estimated continuously, and the symptoms during effort were reported. Results: A significant correlation was found between the symptoms reported by the athletes in the two field tests and the findings recorded with the application of the mHealth monitoring method. However, from the pre-participation screening in the laboratory and from the spiroergometric tests, no abnormal findings were detected that were to blame for the appearance of the symptoms. Conclusions: The application of mHealth monitoring during competitive cycling is a very useful method for the early recording of cardiac and other health disorders of athletes, whose untimely evaluation could lead to unforeseen events.

Effects of human immunodeficiency virus status on symptom severity in influenza-like illness in an otherwise healthy adult outpatient cohort

The impact of HIV on influenza-like illness (ILI) has been incompletely described in the era of combination antiretroviral therapy, particularly in the post-H1N1 pandemic period. This analysis informs on ILI...

Cockroach-induced IL9, IL13, and IL31 expression and the development of allergic asthma in urban children

Cockroach-induced IL9, IL13, and IL31 expression and the development of allergic asthma in urban children

Barriers to entering race training before 4 years of age for Thoroughbred horses born in the 2014 Australian foal crop.

Currently, there is a paucity of data on the barriers for Australian Thoroughbred horses transitioning from stud farm to racetrack. This paper reports the reasons why horses failed to enter race training and documents their exit destinations. Biographical records of Australian Thoroughbred horses born in 2014 were investigated to determine the number of horses that had not officially entered race training by the start of the 4-year old racing season (1 August 2018). Of the 13,677 foals born in 2014, 66% had commenced training and 51% had raced before the beginning of their 4-year-old season in Australia. A sampling frame based on the post code of the premises where foals were born and records from Racing Australia were used to select a geographically representative sample of the 2014 Australian Thoroughbred foal crop (n = 4,124). From the population eligible for sampling 1,275 horses that had not entered training were enrolled in the survey and their breeders were sent an online questionnaire with follow-up phone calls for those who had not responded. Of the 633 responses (50% of 1275) the most frequent outcomes for horses were: death (38%, n = 239), participation in the racing industry in their 4-year old racing season (24%, n = 154) and retirement (16%, n = 100) either as Australian Stud Book (ASB) bloodstock (n = 17), or as horses rehomed outside the Thoroughbred industry (n = 83). Illness or injury was the most frequent reason for horses not entering race training that were ASB bloodstock, rehomed or deceased. There was a loss of traceability at the point of sale with most horses sold at 1 year of age. This study provides important information on the reasons, alternative outcomes and gaps in traceability for horses not entering training prior to the 4-year-old racing season.

Estimated crash injury risk and crash characteristics for motorsport drivers

ObjectiveMotorsport crash events are complex and driver restraint systems are unique to the motorsport environment. The National Association for Stock Car Auto Racing, Incorporated (NASCAR®) crash and medical datasets provide an opportunity to assess crash statistics and the relationship between crash characteristics and driver injury. Injury risk curves can estimate driver injury risk and can be developed using vehicle incident data recorder information as inputs. These relationships may provide guidance and insight for at-track emergency response, driver triage and treatment protocols. MethodEight race seasons of crash and medical record data (including Association for the Advancement of Automotive Medicine Abbreviated Injury Scale (AIS) scores) from the Monster Energy NASCAR Cup Series & NASCAR Xfinity Series were processed and analyzed. Multiple logistic regression modeling was used to produce injury risk curves from longitudinal and lateral resultant change in velocity, resultant peak acceleration, principal direction of force and the number of impacts per incident. Results2065 Unique IDR data files were matched with 246 cases of driver injury or sub-injury (severity below AIS 1) and 1819 no-injury cases. Multiple logistic regression modeling showed increasing resultant change in velocity, resultant peak acceleration and the number of impacts during a crash event all increase estimated driver injury risk. After accounting for the other predictors in the model, right lateral impacts were found to have a lower estimated injury risk. The model produced an Area Under the Receiver Operating Characteristics curve of 0.80. Across the eight race seasons in this study the overall average resultant change in velocity was 34.4 kph (21.4 mph) and the average resultant peak acceleration was 19.0 G for an average of 258 crashes per season. For 2011 through 2015, full time drivers experienced 134 times more crashes per mile traveled than passenger vehicles, but experienced 9.3 times fewer injuries per crash. ConclusionMultiple logistic regression was used to estimate AIS 1+ injury only and AIS 1+ with sub-injury risk for motorsport drivers using motorsport-specific crash and medical record databases. The injury risk estimate models can provide future guidance and insight for at-track emergency medical response dispatch immediately following an on-track crash. These models may also inform future driver triage protocols and influence future expenditures on motorsports safety research.

Prevalence, antibiotic susceptibility and virulence factors of Enterococcus species in racing pigeons (Columba livia f. domestica)

BackgroundThis study was aimed to investigate the intestinal microbiota in racing pigeons with regard to Enterococcus species distribution, virulence factors and antibiotic susceptibility. Three methods (API, Multiplex sodA-PCR, 16S rRNA sequencing) were compared for Enterococcus species identification. Cloacal samples from 179 apparently healthy pigeons of 13 different flocks were tested.ResultsMultiplex sodA-PCR and 16S rRNA gene sequencing showed almost perfect agreement in Enterococcus species identification. Isolates were identified as Enterococcus columbae (34.5%), Enterococcus hirae (20.7%), Enterococcus faecalis (11.7%), Enterococcus faecium (11.7%), Enterococcus gallinarum (9%), Enterococcus mundtii (4.8%), Enterococcus casseliflavus (3.4%), Enterococcus cecorum (2.1%), Enterococcus durans (2.1%). More Enterococcus species were found after the race season than before. The study showed differences between Enterococcus species in relation to 68.8% (22/32) biochemical parameters. Six out of seven virulence genes were detected: gelE (43.5%), asa1 (42.1%), efaA (30.3%), ace (30.3%), cylA (27.6%), and esp (9%). None of the isolates harboured hyl gene. Overall 15.2% of Enterococcus isolates produced gelatinase, but 66.7% gelE genes were silent. Enterococcus faecalis showed the most often efaA, ace and gelatinase activity than other enterococcal species. Nearly all isolates (93.1%) were resistant to at least one antibiotic. The most frequent resistance was to enrofloxacin (80%), doxycycline with teicoplanin (73.1%), erythromycin (49.7%). The study revealed significant differences between some enterococcal species in the antibiotic susceptibility to different antibiotics. Enterococcus columbae and E. cecorum showed significantly more frequent resistance to chloramphenicol than other enterococci. The presence of VRE (19.3%), HLGR (2.8%) and no LRE were found. Overall 30.3% of isolates were positive for vancomycin resistance genes, where vanC1 (E. gallinarum), vanC2-C3 (E. hirae, E. casseliflavus), vanB (E. columbae) predominated.ConclusionsWe conclude, that intestinal microbiota in racing pigeons is composed by 9 different Enterococcus species. Given that racing pigeons are kept in close contact with humans and backyard animals, combined with their long-distance flight abilities, they can serve as potential source of virulent and antibiotic resistant Enterococcus spp. in the environment.

Time-optimal trajectory planning for a race car considering variable tyre-road friction coefficients

This paper shows the planning of time-optimal trajectories, which allows an autonomous race car to drive at the handling limits, taking into account locally changing road friction values. For this purpose, the minimum lap time problem is described as an optimal control problem, converted to a nonlinear programme using direct orthogonal Gauss-Legendre collocation and then solved by the interior-point method IPOPT. Reduced computing times are achieved using a curvilinear abscissa approach for track description, algorithmic differentiation using the software framework CasADi, and a smoothing of the track input data by approximate spline regression. The vehicle's behaviour is approximated as a single track and double track model with quasi-steady state tyre load simplification and nonlinear tyre model. The results are used to evaluate which vehicle physics are important for the calculation of the time-optimal trajectory. The novelty of this work is the consideration of wheel-specific tyre-road friction coefficients along the racetrack using a track friction map. It is shown that variable friction coefficients have a significant impact on the trajectory, and therefore significantly improve lap times on inhomogenous racetracks. The proposed trajectory planning has proven its practical suitability in first tests on an autonomous race car and will be used in the coming racing season in the Roborace competition.

Clinical evaluation of education relating to nutrition and skeletal loading in competitive male road cyclists at risk of relative energy deficiency in sports (RED-S): 6-month randomised controlled trial

ObjectiveTo clinically evaluate education to improve eating behaviour and skeletal loading exercise in male cyclists at risk of poor bone health and impaired performance due to relative energy deficiency in...