A novel ammoniation treatment of barley as a strategy to optimize rumen pH, feed degradability and microbial protein synthesis in sheep

Abstract

BACKGROUND: Meeting the energy and nitrogen (N) requirements of high-performing ruminants at the same time as avoiding digestive disturbances (i.e. rumen acidosis) is a key priority in ruminant nutrition. The present study evaluated the effect of a cereal ammoniation treatment, in which barley grains are combined with urea and enzymes that catalyze the conversion of urea to ammonia to optimize rumen function. Twelve rumen cannulated sheep were randomly divided into two groups and fed a diet containing 60% of ammoniated barley (AMM) or untreated barley supplemented with urea (CTL) to investigate the impact on rumen fermentation and feed utilization. RESULTS: AMM had higher total N content and effective rumen degradable N than untreated barely. AMM sheep had a consistently higher rumen pH throughout the day (6.31 versus 6.03) and tended to have a lower post-prandial ammonia peak and higher acetate molar proportion (+5.1%) than CTL sheep. The rumen environment in AMM sheep favored the colonization and utilization of agro-industrial by-products (i.e. orange pulp) by the rumen microbes leading to a higher feed degradability. AMM sheep also had higher total tract apparent N digestibility (+21.7%) and urinary excretion of purine derivatives (+34%), suggesting a higher N uptake and microbial protein synthesis than CTL sheep. CONCLUSION:The inclusion of AMM in the diet of ruminants represents a valid strategy for maintaining rumen pH within a physiological range and improving N utilization by the rumen microbes, which could have positive effects on the health and productivity of animals in intensive production systems. These findings warrant further studies under conventional farm conditions.

The Effects of Oil Palm Fronds Silage Supplemented with Urea-Calcium Hydroxide on Rumen Fermentation and Nutrient Digestibility of Thai Native-Anglo Nubian Goats

“…The alkali in the lignocellulosic material causes swelling, thereby increasing the internal surface, lowering the polymerization degree and crystallinity, causing the lignin to rupture [26]. The main cause of the increase in CP content is that urea is a non-protein nitrogen that supplies a large amount of nitrogen to the substrate [27]. Since nitrogen binds OPF during fermentation, it promotes rumen bacteria and produces a greater microbial protein in animals.…”

Evaluation of Legumes, Roughages, and Concentrates Based on Chemical Composition, Rumen Degradable and Undegradable Proteins By In Vitro Method

“…The pH of the rumen fluid is one of the determinants of whether or not the rumen conditions are suitable for the fermentation process. Belanche et al (2021) stated that rumen microbial activity requires certain pH conditions related to ongoing rumen environmental conditions. Van Soest (1994) stated that the activity of cellulolytic bacteria was inhibited if the pH of the rumen fluid was below 6.2, and the activity is usually optimal at 6.7±0.5 rumen pH.…”

Effectiveness of Lemuru Fish (Sardinella longiceps) Oil Supplementation on Nutrient Digestibility, Fiber Fraction and Rumen Fluid Fermentability

“…Pazla et al (2018b) states that the optimum pH required for microbial protein synthesis ranges from 6-7. Belanche et al (2021) stated that rumen microbial activity requires certain pH conditions related to ongoing rumen environmental conditions. Van Soest (1994) stated that the activity of cellulolytic bacteria was inhibited when the pH of the rumen fluid falls below 6.2, and the activity would be optimal in the rumen at a pH of 6.7±0.5.…”

“…Van Soest (1994) stated that the activity of cellulolytic bacteria was inhibited when the pH of the rumen fluid falls below 6.2, and the activity would be optimal in the rumen at a pH of 6.7±0.5. Belanche et al (2021) stated that if the rumen pH is less than 6 then it can inhibit the process of proteolysis and deamination because the growth of rumen bacteria will be hampered.…”