Changes of serum mineral concentrations in horses during exercise
Inoue, Y.; Osawa, T.; Matsui, A.; Asai, Y.; Murakami, Y.; Matsui, T.; Yano, H.
Asian Australasian Journal of Animal Sciences 15(4): 531-536
2002
ISSN/ISBN: 1011-2367 Document Number: 259888
We investigated the exercise-induced changes in the serum concentration of several minerals in horses. Four well-trained Thoroughbred horses performed exercise for 5 d. The haemoglobin (Hb) concentration increased during exercise, but recovered to the pre-exercise level immediately after cooling down and did not change again until the end of experiment. The changes in serum zinc (Zn) and copper (Cu) concentrations were similar to those of blood Hb during the experiment. The serum magnesium (Mg), inorganic phosphorus (Pi) and iron (Fe) concentrations also increased during exercise. Though the serum Pi concentration recovered to the pre-exercise level immediately after the cooling down, it decreased further before the end of the experiment. The serum Mg concentration was lower, immediately after cooling down, than its pre-exercise level but gradually recovered from the temporal reduction. The recovery of the serum Fe concentration was delayed compared to that of the other minerals; serum Fe concentrations recovered 2 h after cooling down. The serum calcium (Ca) concentration did not change during exercise but rapidly decreased after cooling down. As a result, it was lower, immediately after cooling down, than its pre-exercise level. It recovered, however, to the pre-exercise level 2 h after cooling down. The temporal increase in the serum concentrations of all minerals, except Ca, is considered to result from the haemoconcentration induced by exercise; whereas, the stable concentration of the serum Ca during exercise is possibly due to its strict regulation of homeostasis. These results indicate that the serum concentration of each mineral responds differently to exercise in horses, which may be due to the differences in the metabolism of these minerals.