Physiological and biochemical response of the draught horse to plowing in rice fields

Abstract

In order to determine the effort performed by crossbred draught horses in agricultural work, the biochemical and physiological response of five horses was evaluated after performing five hours of work (3 in the morning and 2 in the afternoon) with a 90 minutes break between the periods.

Blood samples were obtained from the jugular vein with a vacutainer. The haemoglobin concentration and globular volume were determined in whole blood. Lactic acid was determined in deproteinised blood, while cortisol and enzymatic activities were determined in plasma.

Cardiac and respiratory frequencies increased significantly with the work. These physiological variables were recovered 30 minutes post exercise. Haemoglobin, globular volume, plasmatic cortisol and enzymatic activities of creatine kinases and aspartate aminotransferase increased significantly during the exercise, but lactic dehidrogenase and lactic acid presented no significant changes. The results showed that the muscular effort performed by the horses was very intense, but this exercise did not produce any evident injury or muscular fatigue on the animals.