Plasma biochemistry in the horse during 3‐day event competition

Abstract

Summary Blood samples were collected from 16 Thoroughbred horses before, during and after the second day of a 3‐day event. Plasma osmolality, concentrations of sodium, potassium, chloride, urea, creatinine, glucose, bilirubin, iron, total protein, albumin, alkaline phosphatase, aspartate aminotransferase, alanine aminotransferase, creatine kinase, calcium, inorganic phosphate, uric acid, cholesterol, triglycerides and non‐esterified fatty acids were measured. Significant differences from pre‐event values were found in all parameters with the greatest changes being found after the cross‐country phase. Most parameters showed significant rises following exercise, except calcium and chloride, which decreased. It was deduced from the changes in biochemistry that dehydration, reduced glomerular filtration rate, increased glycogenolysis and increased lipid metabolism, were a result of this form of competitive exercise. Résumé Le sang de 16 Pur Sangs a été prélevé avant, durant et après le second jour d'un concours complet d'équitation. On y mesura les concentrations de sodium, potassium, chlorure, urée, créatine, glucose, bilirubine, fer, protéines totales, albumine, phosphatase alcaline, aspartate aminotransférase, alanine aminotransférase, créatine kinase, calcium, phosphate inorganique, acide urique, cholestérol, triglycérides, acides gras non esterifiés et l'osmolarité du plasma. Des variations significatives furent trouvées pour tous les paramètres, par comparaison avec les valeurs recueillies avant le début du concours complet, les changements les plus importants ayant été constatés après le cross country. Toutes les valuers augmentèrent après exercice, à l'exception de celles du calcium et du chlorure qui diminuèrent. Onnen a déduit que la déshydratation, que la réduction du taux de filtration glomérulaire, que la glycogénolyse accrue et que le métabolisme accru des lipides étaient le résultat de ce type de compétition. Zusammenfassung Von 16 Vollblütern wurde vor, während und nach dem 2. Tag einer Vollmilitary Blut gewonnen. Bestimmt wurden die folgenden Werte: Plasmaosmolalität; Konzentrationen von Natrium, Kalium, Chlorid, Harnstoff, Kreatinin, Glukose, Biliburin, Eisen, Gesamteiweiss, Albumin, Calcium, anorganischem Phosphor, Harnsäure, Cholesterin, Triglyceride, nicht veresterten Fettsäuren und die Aktivitäten von alkalischer Phosphatase, Aspartat‐Aminotransferase, Alanin‐Aminotransferase und Kreatinkinase. Signifikante Unterschiede zu den Resultaten vor der Prüfung ergaben sich bei allen Parametern, mit den stärksten Abweichungen nach der Geländeprüfung. Die meisten Werte erhöhten sich, mit Ausnahme von Calcium und Chlorid, die erniedrigte Konzentrationen aufwiesen. Die biochemischen Veränderungen lassen vermuten, dass derartige Prüfungen zu Dehydrierung, reduzierter glomerulärer Filtration, erhöhter Glykogenolyse und erhöhtem Lipid‐Stoffwechsel Anlass geben.

Weight loss, water loss and cation balance during the endurance test of a 3‐day event

“…These results are comparable with values previously reported in horses competing in the endurance test of a 3-day event (Rose et al 1980b). Since plasma [Na] is maintained within a narrow range, an increase in plasma [Na] may reflect a relative decrease in TBW, due to a movement of fluid out of the extracellular fluid compartment or dehydration due to a loss of fluid in sweat (Leaf 1962: Rose et al 1980b.…”

“…and after completion of phase C were used to calculate the net exchangeable cation concentration [CB]. The plasma [Na] measured after phase C was chosen because previous workers have shown that plasma "a] measured after phase C is similar to plasma [Na] measured 30 rnin after phase D (Rose et al 1980b). Body weight was measured 30 rnin after phase D of competition.…”

“…Furthermore, Thoroughbred racehorses may lose 10 to 15 litres of water during warm-up, race and initial recovery period (Carlson 1987). However, there is little information regarding weight loss, water loss and electrolyte loss in horses in 3-day event competition (Rose et al 1980b;Andrews et a/. 1994).…”

Concentrações séricas de uréia, creatinina, sódio, potássio e cálcio em eqüinos das raças Pantaneira e Árabe submetidos a esforço físico de longa duração no estado de Mato Grosso (cavalgada) Brasil

“…Quanto ao comportamento do cálcio em diferentes modalidades esportivas, com menor freqüência observa-se a diminuição durante provas de longa duração e sempre da metade do percurso para o final, conforme reportado em provas de enduro de 110km (Lucke e Hall, 1978), para eventos de três dias (Rose et al, 1980c), em provas de 160 km (Rose et al, 1983b), em provas de 100km (Oosterbaan et al, 1991), e de 76 km no Pantanal de Mato Grosso (Santos et al, 2001). Relatos do aumento do cálcio foram registrados por Snow et al (1982) em prova de enduro de 80km, à velocidade de 16 a 18 km/hora, ao qual atribuiu a marcada hemoconcentração, que mascarou a perda plasmática ocorrida.…”

“…As alterações dos constituintes sangüíneos durante o esforço físico têm sido discutidas por diversos autores no que se refere às mudanças bioquímicas ocorridas em provas de curta distância (Anderson, 1975;Lucke e Hall, 1978;Lucke e Hall, 1980;Rose et al, 1983a;Toledo et al, 2001), às mudanças eletrolíticas nas provas de longas distâncias (Carlson e Mansmann, 1974;Lucke e Hall, 1978;Snow et al, 1982;Rose et al, 1983b;Oosterbaan et al, 1991;Santos et al, 2001;) e aos efeitos hormonais e metabólicos (Rose et al, 1980c;Snow, 1990). Todas as avaliações objetivam proporcionar meios para um treinamento adequado e o diagnóstico precoce das alterações que interferem com o desempenho.…”