Efeitos do tipo de conservação de forragem no comportamento alimentar de equinos em baia

Abstract

This study aimed to compare feeding behavior under different types of forage conservation in stalled horses fed Tifton 85 hay or Tifton 85 haylage. Eight adult Quarter Horse horses were used and randomly assigned to two experimental treatments (100% hay and 100% haylage). The total experimental period lasted 14 days, with 10 days of adaptation and 4 days for data collection (all horses were evaluated during this period). The feeding management consisted of the daily supply of 10 kg and 6.97 kg of haylage and hay on an as-fed basis, respectively, in addition to four kilograms of commercial concentrate. Voluntary intake, feeding time, number of bites, and chewing movements were quantified. For behavioral evaluation, each animal was filmed for one minute at random times on every experimental day, and bite and chewing rates were determined from these recordings. To characterize the feeds, bromatological analysis was performed to determine dry matter (DM), crude protein (CP), neutral detergent fiber (NDF), and acid detergent fiber (ADF) of the forages. The experiment followed a completely randomized design with two treatments (100% hay or 100% haylage) and four replications, considering each animal as the experimental unit. Means were compared using the t-test at a 5% probability level. Hay and haylage presented 106.8 and 134.7 g of CP, 732.5 and 650.7 g of NDF, 309.5 and 271.0 g of ADF, and 423.0 and 379.7 g of hemicellulose for hay and haylage, respectively. No difference was observed for feeding time. Hay showed a higher bite rate (6.44 bites per minute) compared to haylage (4.31 bites per minute). Haylage showed a higher chewing rate (66.31 chews per minute) compared to hay (60.81 chews per minute). However, haylage resulted in daily refusals in 50% of the animals. Hay provided total intake without refusals, and both forages ensured prolonged and similar feeding times. The mechanical difference lies in ingestion rates: hay requires a higher bite rate due to the difficulty of grasping the drier material, whereas haylage allows the intake of a larger amount of forage at once, increasing the chewing rate. Nevertheless, both diets proved efficient in keeping idle time to a minimum.