During dry seasons, equines are traditionally fed hay. However, if not prepared under favorable climatic conditions and if not properly stored, hay does not preserve its nutritional value. The aim of this research was to evaluate the chemical composition in Stylosanthes guianensis cv. Mineirão and Estilosantes Campo Grande hay varieties, used to feed equines over 225 days of storage. Treatments consisted of Stylosanthes guianensis cv. Mineirão and Estilosantes Campo Grande hay varieties, assessed at six moments of storage: 0, 45, 90, 135, 180, and 225 days. The experiment followed a completely randomized split-plot design. In the comparison between varieties, differences (P<0.05) were found for dry matter, acid detergent insoluble nitrogen, neutral detergent fiber, and lignin. The storage period altered (P<0.05) the concentrations of dry matter, calcium, and crude protein in both hay varieties. The beta-carotene content in the leguminous plants did not decline (P>0.05) over the 225 days of storage. The storage period had little impact on the nutritional quality of the assessed hays. The Stylosanthes guianensis cv. Mineirão and, mainly, Estilosantes Campo Grande hay varieties have potential to be used in equine diet. Key words: Beta-carotene. Chemical composition. Equus caballus.
ResumoDurante a época seca, equinos são tradicionalmente alimentados com feno, entretanto, se não forem preparados em condições climáticas favoráveis e bem estocados, não preservam seu valor nutricional. O objetivo desse trabalho foi avaliar a influência do período de estocagem na composição bromatológica e concentração de betacaroteno dos fenos