Effect of Crude Protein Levels in Concentrate and Concentrate Levels in Diet on <i>In vitro</i> Fermentation

Abstract

The effect of concentrate mixtures with crude protein (CP) levels 10%, 13%, 16%, and 19% and diets with roughage to concentrate ratios 80:20, 60:40, 40:60, and 20:80 (w/w) were determined on dry matter (DM) and organic matter (OM) digestibility, and fermentation metabolites using an in vitro fermentation technique. In vitro fermented attributes were measured after 4, 24, and 48 h of incubation respectively. The digestibility of DM and OM, and total volatile fatty acid (VFA) increased whereas pH decreased with the increased amount of concentrate in the diet (p<0.001), however CP levels of concentrate did not have any influence on these attributes. Gas production reduced with increased CP levels, while it increased with increasing concentrate levels. Ammonia nitrogen (NH3-N) concentration and microbial CP production increased significantly (p<0.05) by increasing CP levels and with increasing concentrate levels in diet as well, however, no significant difference was found between 16% and 19% CP levels. Therefore, 16% CP in concentrate and increasing proportion of concentrate up to 80% in diet all had improved digestibility of DM and organic matter, and higher microbial protein production, with improved fermentation characteristics.

Effect of Dietary Concentrate to Roughage Ratio on Nutrient Digestibility, Rumen Fermentation, Growth Performance and Serum Acute Phase Protein in Growing Buffalo Calves

“…In the current study increasing concentrate in diets was increased (p<0.01) rumen total volatile fatty acids and ammonia nitrogen concentration. This result support the finding of previous studies performed by Cantalapiedra-Hijar et al (2009), Agle et al (2010) andVan Dung et al (2014). The higher rumen volatile fatty acid produced from feeding high concentrate diet decreased (P<0.01) rumen pH as compared with high roughage diet.…”

Use of Lysozyme as a Feed Additive on In vitro Rumen Fermentation and Methane Emission

“…This non-significant different DM and OM disappearance results are also consistent with the results observed by Soriano et al (2014), where they elicited in vitro DM and OM disappearance with Lactobacillus mucosae on dried brewers grain. The results observed in our experiment tended towards higher DM and OM disappearance, whose ultimate effect on higher in vitro total VFA production supported by Van Dung et al (2014), where they reported higher DM and OM disappearance with concentrate:roughage (8:2) substrate along with higher in vitro total VFA production. We found a significant decrease in CH 4 concentration after 12 and 24 h of incubation which is in concordance with the result of Mamuad et al (2014), where significantly lower in vitro CH 4 concentration was revealed.…”

0231 Effects of static or oscillating dietary crude protein levels on fermentation dynamics of beef cattle diets using a dual-flow continuous culture system

“…In the present study it was not expected changes in ruminal digestibility of DM, OM, and fiber; therefore, changes in total VFA and individual VFA molar proportion were unlikely to occur. Similarly to our observations, other studies have reported that increasing dietary CP levels had no significant effect on total VFA concentration [29] [33].…”

“…Factors that affect total VFA concentration and individual VFA molar proportions include level of intake, ruminal digestibility (DM, OM, and fiber), passage rate, dietary composition, and forage to concentrate ratio [33] [34]. Because these variables did not change in the present study it is sensible and consistent to expect that total VFA concentration and individual VFA molar proportions would not change.…”

“…Archibeque et al [31] reported that steers fed increasing CP levels or oscillating dietary CP levels had greater DM digestibility, ranging from 71.8% (9.1% CP) to 77.7% (14.9% CP), and 77.5% when oscillating from 9.1% to 14.9% dietary CP. Factors such as CP levels and sources may affect the response of CP on digestibility [32] [33].…”