Metabolic and Oxidative Stress in Endurance Horses during Racing

Daljinsko jahanje fizički je najzahtjevnija disciplina konjičkog sporta. U istraživanje su uključena 53 konja koja su uspješno završila utrku na jednome od četiri promatrana natjecanja daljinskog jahanja u Republici Hrvatskoj. Uspoređivana je prosječna brzina kretanja i prosječno vrijeme oporavka konja u odnosu na dob, spol, pasminu i iskustvo te dužinu staze. Konjima su u svrhu istraživanja metaboličkog i oksidacijskog stresa uzimana dva uzorka krvi, prije i nakon utrke. Istraživani su odabrani serumski biokemijski parametri, a kao pokazatelji oksidacijskog stresa korišteni su test determinacije reaktivnih metabolita kisika (d-ROMs), malondialdehid (MDA) i biološki antioksidansni potencijal (BAP). Konji arapske pasmine imali su kraće vrijeme oporavka. Dob, spol i iskustvo konja nisu imali znatan utjecaj na vrijednosti promatranih parametara. Vrijednosti kreatin kinaze i glukoze u krvi (GUK) prije utrke bile su više od referentnih vrijednosti. Vrijednosti bubrežnih parametara i parametara mišićnog oštećenja bilježe porast poslije utrke te je razlika znatnija na većim dužinama utrka. Povećanjem dužine utrke povećava se i gubitak elektrolita. Znatan porast vrijednosti svih promatranih pokazatelja oksidacijskog stresa zabilježen je poslije utrke. BAP bilježi veći porast na utrkama od 80 km u odnosu na kraće utrke, a s njegovim porastom proporcionalno su rasle vrijednosti ureje i triglicerida. MDA i GUK proporcionalno su rasli, što upućuje da zabilježena hiperglikemija utječe na lipidnu peroksidaciju stanice. Utrke daljinskog jahanja uzrokuju pojačane zahtjeve organizma koji se očituju povećanim gubitkom elektrolita, aktivnosti mišićnog i mokraćnog sustava te oksidacijskim stresom.Endurance riding is the most physically demanding discipline of equine sport. The study included 53 horses that successfully completed the race in one of the four observed endurance riding competitions in Croatia. The average speed and recovery time were compared to age, sex, breed, experience and length of the race track. Two blood samples were taken from horses for the purpose of metabolic and oxidative stress research, one before and one after the race. The analysis consisted of several serum biochemical parameters, as well as determination of reactive oxygen metabolites (d-ROMs), malondialdehyde (MDA) and biological antioxidant potential (BAP) as indicators of oxidative stress. Horses of Arabian breeds had shorter recovery time. Age, sex and horse experience did not have a significant influence on the studied parameters. Creatine kinase and blood glucose values prior to the race were higher than reference values. Values of renal parameters and parameters of muscle damage increased after races, and the degree of change was more significant at longer racing lengths. Electrolyte loss was more pronounced during longer races. Significant increase in all observed oxidative stress markers were recorded after the race. BAP has recorded higher values during longer races. Positive correlations were recorded for BAP, urea and triglyceride concentrations. MDA and blood glucose have increased proportionally, indicating that hyperglycemia affected cells lipid peroxidation. Endurance riding causes increased body requirements that are manifested by increased electrolyte loss, muscular and urinary system activity, and oxidative stress

Doping u konjičkom sportu

Uporaba lijekova i drugih sredstava s ciljem poboljšanja sportske izvedbe konja poznata je od davnina, a aktualna je danas. Međunarodna konjička organizacija (Federation Equestre Internationale, FEI) propisala je postupak provođenja dopinške kontrole koja uključuje prikupljanje uzoraka krvi i urina od svakoga konja, podjele uzoraka na uzorak A i B te slanje potpuno anonimnih zapečaćenih uzoraka u laboratorij. Napretkom tehnologije usavršavaju se i laboratorijske metode za dokaz nedopuštenih sredstava u uzorcima kao što su LC/MS, GC/MS, ELISA, tankoslojna kromatografija te kapilarna elektroforeza. FEI razlikuje dvije skupine nedopuštenih sredstava: „zabranjene tvari“ i „kontrolirani lijekovi“, s ciljem odvajanja liječenja od ciljanog dopinga sportskih konja. Obvezno je osigurati da konji ne budu tretirani ili hranjeni tvarima koje su zabranjene za uporabu tijekom natjecanja i tvari koje nisu dopuštene za korištenje u konja u bilo kojemu trenutku. Uloga veterinara prije svega je briga da tijekom liječenja dobrobit konja nikad nije ugrožena primjenom lijeka, u vremenu preblizu natjecanju, koji može maskirati simptome i pogoršati kliničko stanje

The role and importance of veterinarians in endurance riding

Daljinsko jahanje (engl. endurance riding) jest konjička sportska disciplina u kojoj se procjenjuje sposobnost jahača i spremnost konja da u što kraćem vremenu prijeđu određenu udaljenost na zadanoj stazi. Ovisno o kategoriji natjecanja, konji prelaze od 40 do 160 kilometara u jednom danu natjecanja. Sama je disciplina iznimno zahtjevna i iscrpljujuća te traži dobru pripremu i odličnu fizičku spremu životinje. Iako samo zdravi konji mogu sudjelovati u daljinskom jahanju, prije, tijekom i nakon natjecanja obvezno se provodi rigorozan veterinarski pregled. Povećanjem broja konja koji sudjeluju u natjecanjima daljinskog jahanja raste potreba za edukacijom veterinara o ovoj disciplini s ciljem što uspješnijeg liječenja specifičnih ozljeda lokomotornog sustava i metaboličkih bolesti koje se pojavljuju kao posljedica treninga ili iscrpljujućeg natjecanja.Endurance riding is a sporting discipline in which the ability of the rider and the readiness of the horse to cross a certain distance along a given path are tested. Depending on the category of the competition, the horses cover from 40 to 160 kilometres in one day of competition. The discipline itself is extremely challenging and exhausting, requiring good preparation and great physical endurance in the animals. Although only healthy animals may compete in endurance riding, veterinary inspection before, during and after the competition is mandatory and rigorous. The increasing number of horses participating in such competitions increases the need for training veterinarians within the discipline. The purpose of this training is to treat successfully specific injuries of the locomotor system and metabolic diseases, which occur as a result of training or exhausting competitions

Exhausted horse syndrome

Sindrom iscrpljenosti konja (engl. exhausted horse syndrome, EHS) podrazumijeva multisistemski poremećaj u konja koji kroz duži vremenski period sudjeluju na natjecanjima, posebno pri toplijim vremenskim uvjetima. Zbog pretjeranog tjelesnog napora dolazi do dehidracije, hipovolemije, gubitka elektrolita, poremećaja acido-bazne ravnoteže, gubitka zaliha energije i hipertermije. Klinička slika ovisi o stupnju i brzini javljanja umora u konja te o toleranciji pojedinog konja na tjelesni napor. Dijagnoza se postavlja na temelju anamneze, kliničkih znakova i rezultata laboratorijskih pretraga. U težim se slučajevima dijagnoza lako postavlja, dok je rano prepoznavanje zbog blagih simptoma i nedostatka objektivnih kliničkih i dijagnostičkih kriterija otežano. Cilj terapije navedenog sindroma je trojak: snižavanje tjelesne temperature, nadoknada izgubljene tekućine i elektrolita te obnova cirkulirajućeg volumena krvi. Prognoza u slučaju blagog sindroma iscrpljenosti je dobra, dok je kod težih slučajeva zbog mogućih komplikacija pa čak i smrti životinje upitna. Sindrom iscrpljenosti konja moguće je prevenirati odabirom pasmine konja koja je pogodna za veću tjelesnu aktivnost, održavanje zdravlja konja redovitim veterinarskim pregledima, umjereno pojačavanje intenziteta treninga te izbjegavanje napornih kondicijskih treninga kroz više uzastopnih dana. Od izrazite je važnosti procjena zdravstvenog stanja konja od strane jahača tijekom cijelog natjecanja.Exhausted horse syndrome is a multi- systemic disorder in sport horses subjected to long term physical activity, especially during hot weather conditions. Increased physical activity can lead to dehydration, hypovolemia, electrolyte loss, acid-base imbalance, depletion of energy reserves and hyperthermia. The clinical presentation depends on the severity and speed of onset of fatigue, and on the individual tolerance of the horse to exercise intensity. Diagnosis is based on the anamnesis, clinical signs and laboratory findings. In severe cases, the diagnosis is easily established, whilst early recognition in mild cases is difficult due to the subtlety of clinical signs and lack of objective clinical and diagnostic criteria. The treatment goal is comprised of three main approaches: decreasing body temperature, replacing fluids and electrolytes, and restoring circulating blood volume. Prognosis is good in mild cases, while in severe cases, presentation is questionable due to possible complications, with the possibility of a lethal outcome. Prevention of exhausted horse syndrome is possible by choosing the appropriate horse breed for the sport, maintaining horse health through regular veterinary inspection, gradually increasing training intensity, and avoiding demanding conditioning training lasting several days in a row. The rider’s evaluation of horse health through the competition is of great importance

Effect of prolonged submaximal exercise on serum oxidative stress biomarkers (d-ROMs, MDA, BAP) and oxidative stress index in endurance horses

Abstract Background Oxidative stress (OS) associated with an intense exercise may have a negative influence on equine health. The aim of this study was to determine the effects of endurance races on oxidative and antioxidative status of horses by evaluating changes in reactive oxygen metabolites (d-ROMs), malondialdehyde (MDA), biological antioxidant potential (BAP) and oxidative stress index (OSI) values. The study was carried out on 53 race starts (28 individual horses) competing at different endurance races according to distance (40 and 80 km) and difficulty (easy and demanding). Blood samples were taken before and after the race. Results Compared to levels of OS serum biomarkers before the race, an increase in values of d-ROMs (P <  0.01), MDA (P <  0.01), and BAP (P <  0.001), and a decrease in OSI (P <  0.001) have been noted after the race. Contrary to other measured biomarkers, BAP did not show significant individual effects of horses. Horses competing at shorter races have shown a significant change in d-ROMs (P = 0.002), BAP (P <  0.001) and OSI (P = 0.004), whereas those competing at longer races in MDA (P = 0.002), BAP (P <  0.001) and OSI (P <  0.001) post-race values. Endurance racing induced changes in values of d-ROMs, BAP and OSI during both easy and demanding races. Conclusions Changes in all measured OS biomarkers indicate that prolonged aerobic exercise during endurance race could contribute to the imbalance between oxidants and antioxidants in horses, mainly characterised by a pronounced antioxidant response. Biological antioxidant potential was found to be the most reliable biomarker of OS in endurance horses in the present study