This study was carried out to evaluate intake, apparent nutrient digestibility and water balance in horses fed on different forms of coast-cross hay. Four crossbreed horses, 30 months of age and 200 kg body weight were used. Horses were fed coast-cross hay in four physical forms: long hay; chopped hay (5 cm); ground hay (5 mm) and ground hay (3 mm). The experiment was performed in a 4 × 4 Latin Square design with 15 days for each experimental period (10 days for adaptation to the diets, four days for feces collection and one day for urine collection). Apparent nutrient digestibility was estimated by total feces collection and urinary collection was carried during 24 hours by urine collectors. Apparent digestibility coefficients and nutrient intake did not differ among the diets but the intake time was reduced with hay processing. There was greater water retention, estimated by water balance, when chopped hay or ground hay (3 mm) were fed. Intake and nutrient digestibility were not influenced by levels of hay grinding, but water balance was influenced by the different forms of hay, but a direct relationship was not observed between fiber length reduction and increased water retention.
digestion; digestible fiber; particle size
