ABSTRACT This study aimed to evaluate the amount of fiber in the diet that is able to promote better use of nutrients in the diet of dairy goats when forage palm is the main source of roughage. Fifteen Alpine dairy goats were distributed in a 5 × 5 triple Latin square containing five treatments and five periods, and each treatment contained. We tested five diets composed of different contents of neutral detergent fiber from Tifton hay (NDFf) in the dry matter of rations containing forage palm: D1: 11.98%; D2: 18.31%; D3: 23.68%; D4: 28.76% and D5: 32.12% NDFf. The intake of dry matter, crude protein, neutral detergent fiber, non-fiber carbohydrates and ether extract decreased linearly with the increase in NDFf content. There was a linear increase of milk production and milk protein with increasing dietary NDFf. The fat, dry extract, protein, pH and acidity of the evaluated milk were not affected by increasing the levels of NDFf in the diet. In situations where dairy goats are fed forage palm and other types of forage are limited, 11.98% NDF from forage other than palm can be used as an effective source of NDF.