The Improvement of Maize Cobs Quality through Soaking in Firewood Ash Filtrate and Its Impact on In Vitro Rumen Fermentability and Digestibility

Abstract

Maize cobs can be used as a ruminant's feed, but low digestibility and its quality can be improved by soaking in firewood ash filtrate (FAF). The study aimed to test FAF treatments' effect on rumen fermentation and digestibility using a completely randomized design. Firewood ashes were obtained from Sumedang, Indramayu, and Bogor Regencies. The maize cobs were soaked by FAF at a ratio of 1:1 (w/v) for 3 hours at different concentration, i.e. 0.05 w/v (FA5), 0.10 w/v (FA10), 0.15 w/v (FA15), and 0.20 w/v (FA20). In vitro evaluation was done to measure the fermentability and digestibility of diets containing maize cobs soaked by FAF 0.20 w/v at the levels of 10% (MFA10), 20% (MFA20), 30% (MFA30), and 40% (MFA40). The results showed that firewood ash contained Calcium (Ca, 10.03%), Magnesium (Mg, 1.45%), Sodium (Na, 0.91%), and Potassium (K, 3.11%). The pH of FAF ranged from 11.46 to 12.16. The levels of neutral detergent fiber (NDF), acid detergent fiber (ADF), lignin, cellulose, hemicellulose, and crude fiber (CF) decreased significantly (p <0.05) along with increased FAF concentration. The use of maize cobs soaked by FAF 0.20 w/v with 30% in the diets yielded the highest values of NH3, volatile fatty acids (VFA), dry matter digestibility (DMD), and organic matter digestibility (OMD) (p <0.05). The concentration of 0.20 w/v has resulted in the highest decrease in lignin content of maize cob while their uses up to 30% in the diets provided the best in vitro rumen fermentability and digestibility.