In vitro rumen fermentability of the pelleted feed containing water spinach (Ipomoea aquatica)

Abstract

An in vitro technique based on two stages of batch culture was used to clarify fermentability and digestibility of pellet feed containing water spinach (Ipomoea aquatica). The portion of Pennisetum purpureum in the pellet feed was substituted with Ipomoea aquatica at respective levels of 0% (T1), 20% (T2), 40% (T3) and 60% (T4). The treatments were allocated in a completely randomized design with 5 replicates of each. The results showed that the substitution of water spinach in pellet did not effect on pH, ammonia (NH3), enzyme protein and microbial protein. Volatile Fatty Acids (VFA), acetate (C2), propionate (C3), butyrate (C4), methane (CH4) and carbon dioxide (CO2) were decreased (p<0.05) by water spinach substitution level in the treatments. The ratios of C2: C3 were increased (P<0.05) in both of T3 and T4. The increasing water spinach substitution level enhanced (p<0.05) dry matter digestibility and organic matter digestibility but crude fiber digestibility was unaffected. In conclusion, substitution of Pennisetum purpureum with Ipomoea aquatica at the level of 20% may be the best fiber source for ruminant diet.