Additives on in vitro ruminal fermentation characteristics of rice straw

Abstract

-The objective of this study was to evaluate the effects of mineral and protein-energy (MPES), exogenous fibrolytic enzyme supplements (ES), combination of MPES + ES, and straw without supplement (WS) on digestibility, fermentation kinetic parameters, cumulative gas production, methane, CO 2 production, and volatile fatty acid concentration of rice straw of low and high nutritional value, estimated by in vitro techniques. The experimental design was randomized and factorial 2 × 4: two straws (low and high nutritional value) incubated with four supplements (MPES, ES, MPES + ES, and WS) and their interactions. Four experimental periods were used, totaling four replications per treatment over time. Data were analyzed by PROC MIXED of SAS. The in vitro dry matter and organic matter digestibilities of the rice straw with high nutritional value was improved by MPES, while the combination of MPES + ES supplements inhibited the digestibility of this straw. Dietary carbohydrate and nitrogen increased through MPES and MPES + ES supplements resulted in an increase in NH 3 -N concentration and a decrease in CO 2 production due to the microbial mass formation. However, this increase was not enough to improve organic matter degradability parameters, cummulative gas production, gas production kinetics, and acetate:propionate ratio and reduce methane emissions. The straw with high nutritional value showed greater content of nitrogen fraction a, effective degradability, cummulative gas production, and methane and CO 2 productions comparing with low-nutritional value straw. The use of MPES and MPES + ES supplements can be used as strategy to mitigate CO 2 in ruminant production systems that use rice straw.Key Words: digestibility, digestion kinetics, fatty acid, gas production, methane Revista Brasileira de Zootecnia

Evaluation of cellulolytic exogenous enzyme-containing microbial inoculants as feed additives for ruminant rations composed of low-quality roughage

“…From these results, it could be suggested that biodual supplements increase the digestion of carbohydrate directly and of nitrogen indirectly, consequently increasing ammonia concentration. These results are in line with those reported by Peripolli et al (2017), who noted that fibrolytic enzymes tended to increase ammonia concentration in in vitro fermentation studies.…”

“…Our results also disagree with those of Kurihara (1995), who observed that CH 4 production in less digestible forage was lower than that in highly digestible forage. Ammonia concentration generally acts as an indicator of protein digestibility (Peripolli et al, 2017). The average ammonia concentration of all treatments ranged from 100.7 to 126.7 mg/ day, which is within the normal range required for optimal fermentation and rumen microbial growth (Anantasook and Wanapat, 2012).…”

“…Ammonia concentration generally acts as an indicator of protein digestibility (Peripolli et al ., 2017). The average ammonia concentration of all treatments ranged from 100.7 to 126.7 mg/day, which is within the normal range required for optimal fermentation and rumen microbial growth (Anantasook and Wanapat, 2012).…”

“…These results are in line with those reported by Peripolli et al . (2017), who noted that fibrolytic enzymes tended to increase ammonia concentration in in vitro fermentation studies.…”

In Vitro Evaluation of Paddy Straw Treated with Maize Spent Liquor at Varying Levels and Different Days of Incubation

“…Similar findings were reported by Malumba et al (2015). Peripolli et al (2017) reported that, paddy straw supplemented with mineral and protein-energy supplements (MPES) significantly increased (p<0.05) in vitro DM and OM digestibility.…”