Evidence of In Vivo Absorption of Lactate and Modulation of Short Chain Fatty Acid Absorption from the Reticulorumen of Non-Lactating Cattle Fed High Concentrate Diets

Abstract

Short-chain fatty acids (SCFAs) and lactate are endproducts of rumen fermentation and important energy sources for the host ruminant. Because their rapid accumulation results in ruminal acidosis, enhancement of the absorption of SCFA and lactate across reticuloruminal wall is instrumental in increasing energy supply and preventing ruminal acidosis in cattle. This study investigated whether the reticuloruminal absorption of SCFAs and lactate was altered by different strategies of high concentrate feeding. Eight rumen-cannulated, non-lactating Holstein cows were fed a forage-only diet (baseline) and then gradually adapted over 6 d to a 60% concentrate level. Thereafter, this concentrate-rich diet was fed for 4 wk either continuously (Con; n = 8) or interruptedly (Int; n = 8). Absorption of SCFAs and lactate was determined in vivo from the experimental buffer introduced into the washed reticulorumen. The buffer contained acetate, propionate, butyrate and lactate at a concentration of 60, 30, 10 and 5 mmol/L, respectively and Cr-EDTA as a marker for correcting ruminal water fluxes. The reticuloruminal absorption after 35 and 65 min of buffer incubation was measured at the baseline, after 1 wk of 60% concentrate feeding in the interrupted model (Int-1) and after 4 wk of concentrate feeding in both feeding models (Int-4 and Con-4). Data showed that the absorption rates of individual and total SCFAs during the first 35 min of incubation of Con-4 were highest (~1.7 times compared to baseline), while Int-1 and Int-4 were similar to respective baseline. Lactate was not absorbed during forage-only baseline and 1-wk concentrate feeding, but after 4-wk feeding of concentrates in both models. In conclusion, SCFAs absorption across the reticulorumen of non-lactating cattle was enhanced by the 4-wk continuous concentrate feeding, which seems to be more advantageous in terms of rumen acidosis prevention compared to the interrupted feeding model. The study provides evidence of lactate absorption across the reticulorumen of non-lactating cattle after both continuous and interrupted 4-wk concentrate feeding.

Graded replacement of maize grain with molassed sugar beet pulp modulated ruminal microbial community and fermentation profile in vitro

“…Concentrations of SCFA were analyzed using gas chromatography as described previously . Ammonia‐N concentration was measured photometrically using the indophenol method .…”

“…Concentrations of SCFA were analyzed using gas chromatography as described previously. 17 Ammonia-N concentration was measured photometrically using the indophenol method. 18 Light absorbance of the prepared samples was measured at 655 nm wileyonlinelibrary.com/jsfa using a photometer (UV-1800, Shimadzu Corporation, Kyoto, Japan).…”

Intramammary infusion of Escherichia coli lipopolysaccharide negatively affects feed intake, chewing, and clinical variables, but some effects are stronger in cows experiencing subacute rumen acidosis

“…The severity and duration of SARA conditions are particularly relevant for rumen health (Khafipour et al, 2009;Schwaiger et al, 2013). Recent research of our team observed that intermittent SARA conditions are stronger than persistent SARA conditions, likely because the rumen and its microbiota have less chance to adapt and the VFA are less absorbed across the reticulorumen wall Qumar et al, 2016;Wetzels et al, 2016). The latter is a major concern, as VFA absorption is essential for the regulation of the intraruminal pH and the alleviation of SARA conditions (Aschenbach et al, 2011;Schwaiger et al, 2013).…”

Probiotic Supplement Improves the Health Status and Lactation Performance in Dairy Animals

“…Food goes down to the reticulorumen from the esophagus, and this is like a fermentation chamber which converts plant carbohydrate to volatile fatty acids, lactate, hydrogen, and methane which are used by the ruminant host. In ruminants, process starts with the peptic digestion in the abomasum [23].…”