3.2. Energy and dry matter digestibility
There were significant interactions between plant sources and fish species for energy and dry matter digestibility, indicating that plant sources affect digestion differently, depending on the fish species. Thus, highest energy digestibility coefficients were observed in tilapia when fed broken rice and ground corn, while no differences were observed in jundiá (Table 4). Tilapia presented higher dry matter digest- ibility coefficients than those shown by jundiá catfish (Table 4). The highest dry matter digestibility was observed for broken rice, followed by ground corn. The lowest dry matter digestibility coefficients were observed when both species were fed wheat bran and cassava residue, the most fibrous sources (Table 4). This performance is reflected in correlation between starch or dietary fiber content with energy or dry matter ADC (Table 3). For jundiá, there was no correlation between starch content and energy ADC, while a positive correlation was observed for tilapia. For both fish species, starch content indicated significant positive correlation with dry matter ADC. Dietary fiber ADC for both fish species (Table 3).