Aroeira (Myracrodruon urundeuva) and Malva (Herissantia crispa) have forage potential for ruminant nutrition in arid regions.

The Caatinga biome has a wide variety of plants which, despite their irregular distribution, are frequently used to feed animals. This study aimed to evaluate the gas production kinetics of Caatinga plants: Malva (Herissantia crispa), Aroeira (Myracrodruon urundeuva), Marmeleiro (Croton sonderianus), and Bamburral (Hyptis suaveolens). Buffel grass (Cenchrus ciliaris), a cultivated forage, was used as a control. For this evaluation, samples of Aroeira, Malva, Marmeleiro, Bamburral, and Buffel grass were weighed and then incubated in 100 ml flasks containing rumen fluid and buffer solution at 39 °C in a water bath. The volume of gases produced was measured with graduated syringes at various times. The parameters of in vitro degradation kinetics were estimated from cumulative gas production using the NLMIXED procedure of SAS (Statistical Analysis System, Cary, USA). Buffel grass showed higher gas production than the other samples (77.64 ml), followed by the Caatinga samples, Malva and Aroeira (58.16 ml and 54.05 ml, respectively), which were statistically similar. In conclusion, we suggest that Malva and Aroeira are forage plants with promising potential to improve the nutrition of ruminants in arid regions, given their high protein content, moderate fiber content, and characteristics related to gas production identified with the in vitro digestibility test.