Composição miofibrilar do glúteo médio de equinos de concurso completo de equitação na fase inicial do treinamento

Bruno Gonçalves De Souza,Fernando Queiroz De Almeida,Juliana Da S Leite,Cristiano Chaves Pessoa Da Veiga,Gabriela Ferreira De Oliveira,Simone Bizerra Calado,Ana Maria Dos Reis Ferreira

doi:10.29374/2527-2179.bjvm0087

Abstract

The studies of myofibrillar composition in athletic horses make it possible to best direct them according to their specific fitness and certainly saves time and resources in the preparation of these athletic animals. Through the technique of percutaneous muscle biopsy and different enzyme-histochemical techniques have been possible to classify these fibers in three different types, type I, IIA and IIX. This information can be applied in the selection of those horses and to the possibility the proper conduct of training protocols. In order to evaluate the myofibrillar composition of Gluteus Medius to the selected mode of Eventing by Army Riding School -RJ, thirteen horses, crossbred breeds of Hanoverian, Thoroughbred and Brazilian Equestrian, in the age range 6-12 years, were used. All animals were submitted to a percutaneous muscle biopsy procedure and the fragments subjected to enzyme-histochemical techniques for distinguishing the three different types of muscle fibers by assessing the reactivity of the enzyme adenosine triphosphate miosinica ( mATPase ) and succinate dehydrogenase ( SDH). The animals used had an average relative distribution of different types of muscle fibers apparently quite homogeneous, with 25.9 %, 35.7 % and 38.4 % of fibers of type I, IIA and IIX, respectively, but lying statistically significant difference , with a higher proportion of type II fibers compared to type I , suggesting that it was a direct genetic influence of the training squad races of the Brazilian Army .

Highlights

The studies of myofibrillar composition in athletic horses make it possible to best direct them according to their specific fitness and certainly saves time and resources in the preparation of these athletic animals
Nos casos onde a distinção das tonalidades de castanho não era tão evidente com esta técnica, realizou-se a diferenciação das fibras, especialmente as do tipo II em IIA e IIX, utilizando-se a comparação de campos da técnica da mATPase com os cortes seriados submetidos a técnica da succinate dehydrogenase (SDH) (Figura 3), e assim foi possível determinar as proporções relativas de cada tipo de fibra muscular em todos os animais deste estudo
Como o plantel da Escola de Equitação do Exército (EsEqEx) conta apenas com animais provenientes do cruzamento das raças PSI, Hanoveriano e BH, em diferentes graus de sangue, acredita-se que as proporções relativas dos três diferentes tipos de fibras musculares encontradas nestes animais, tenha sofrido grande influência genética, evidenciada pela predominância de fibras do tipo IIA e IIX, como frequentemente descrito na literatura para animais das raças supracitadas (Rietbroek et al, 2006; DAngelis et al, 2006; Islas et al, 1998)