Serum mineral reference values in athlete Brazilian four-beat gaited horses

Resumo

Little is known about the serum mineral profiles of Brazilian four-beat gaited horses, and this information could be used to improve their nutritional and exercise evaluation programs. This study aimed to determine the mineral values of athlete Campolina and Mangalarga Marchador horses performing two different gait types. One hundred adult horses (7 ± 3 yr and 432 ± 59 kg; mean ± SD) were grouped as follows: 25 batida gait Campolinas (CAMPb), 25 picada gait Campolinas (CAMPp), 25 batida gait Mangalarga Marchadors (MMb), and 25 picada gait Mangalarga Marchadors (MMp). They were fed fresh elephant grass (15 - 20 kg as-fed/day) and commercial concentrate (5 - 7 kg as-fed/day) as well as commercial mineral salt and water ad libitum. Horses were exercised three times a week (~40 – 50 min/day), and ~60% of the exercise comprised a speed session ranging from 3.0 to 4.0 m/s. Blood samples were collected after 12 h feed fasting and at least 24 h after exercise. Mineral concentrations were analyzed using ANOVA and Tukey’s test (p ≤ 0.05). No breed or gait effects were observed (p > 0.05) on serum levels of chloride, potassium, sodium, magnesium, iron, and selenium. There was a breed by gait effect (p < 0.05) on calcium and phosphorus levels. Lower calcium levels were found in MMb (2.13 ± 0.02 mmol/L, p < 0.0032), while lower phosphorus levels were found in MMp (1.43 ± 0.02 mmol/L, p < 0.0005). The mineral values provided by the current study serve as reference values and are useful in the improvement nutritional and exercise evaluation programs of athlete four-beat gaited horses.