Two experiments were conducted to determine the in vitro solubility of dry matter and crude protein of wet feed and dry feed of a commercial broiler diet. In the first experiment, to two g of feed samples of a commercial broiler pelleted diet was added 0-dry (80 g/kg water content) and 1.5 g water per g of leed (640 g/kg water content), and they were then incubated at one of two different levels of pepsin-HCl solutions, low (48 mg pepsin in 2 ml 0.1 M HCl), or high (64 mg pepsin in 3 ml 0.1 M HCl) for 0, 15, 30, 60, 120, 180, and 240 minutes at 42 degreesC. In the second experiment, to 2 g of a commercial broiler feed was added 0-dry (80 g/kg water content), 0.2, 0.4, 0.6, 0.8, 1.0. 1.5, 1.8, and 2.0 g water per g of dry feed (240, 340, 430, 480, 540, 580, 630, and 700 g/kg water content, respectively). To each feed sample was also added 64 mg pepsin with 3 ml-HCl (the high level from experiment 1), and then incubated for 10, 20, 30, 60, 180 and 240 minutes at 42 degreesC. After filtration and drying processes, dry matter and crude protein analyses were done for each sample.