Drying methods and chemical quality of forages evaluated by near infrared spectroscopy

The determination of dry matter (DM) of forages is carried out in feed analysis laboratories mainly with the aid of a forced ventilation oven (FVO), a slower technique than the determination using a microwave oven (MO). Thus, the objective was to evaluate the influence of 2 drying methods on the nutritional composition of forages evaluated by Near Infrared Spectroscopy (NIRS). Six forage species were evaluated, dried in a forced ventilation oven (FVO) and microwave oven (MO). The experimental design used was completely randomized in a 2 x 6 factorial arrangement (2 drying methods and 6 forage species). Then, the drying methodology influenced only the DM contents of the Paiaguás and Marandu cultivars, presenting lower values ​​when dried in MO. For crude protein levels, the cultivar Xaraés was lower when dried in FVO, opposite behavior to that observed for Marandu, which showed lower value through MO. The NDF and ADF contents were not influenced by drying methods. The use of MO for the determination of DM is promising however further studies are needed to evaluate possible changes in the composition of the feed, mainly when evaluated by NIRS.