Effects of Isoacids, Urea, and Sulfur on Ruminal Fermentation in Sheep Fed High Fiber Diets

Abstract

The effects of isoacids, urea N, and S on ruminal fermentation of sugarcane bagasse- or corn stover-based diets were studied in sheep. Acetate production was taken as a measure of the fermentation rate. For the sugarcane bagasse diet, neither urea nor S supplementation changed ruminal acetate production. When N and S were combined, acetate production was 44% higher (3.16 vs. 2.18 mol/d). Similar effects were noted for the corn stover diet. Increasing the level of isoacids from .1 to .2 g/kg BW per d in the diet did not change acetate production for either diet. However, N supplementation of the sugarcane bagasse diet containing the low level of isoacids resulted in a 49% greater acetate production (2.86 vs. 1.91 mol/d). Acetate production was 90% higher (3.74 vs. 1.97 mol/d) when the diet containing the high level of isoacids was supplemented with N. The corresponding increases for corn stover were 12% (2.64 to 2.95 mol/d) and 35% (2.88 to 3.87 mol/d). The results suggest that NH3 N provided by the basal diet was more limiting than isoacids. Once the N deficiency was corrected, isoacids became limiting. Ruminal digestion of high fiber diets low in N was improved by supplementation with urea, isoacids, and S.

Correlation between microbial enzyme activities in the rumen fluid of sheep under different treatments

“…Data for this aspect of the isoacid effect which is in agreement with Bryant [11], Dehority and Scott [18]; Gorosito et al [26], Brondani et al [10] are shown in Tables II, III and IV. CFRF and EABC fractions for oil treatment showed more cellulolytic activity than the control (P < 0.05). Recent work [22] has shown that glycerol and galactose arising from lipid hydrolysis are fermentable.…”

“…Use of phenylacetic acid as a branched-chain fatty acid has been reported by Hefner et al [28]. The use of isoacid [10,20,43,60] is coupled with microbial growth, which also needs NH 3 as a component for protein synthesis. Lipids can also be used to manipulate the digestion and absorption of different nutrients [32,34,35].…”

“…The use of isoacids [10,20,43,60] and lipids [22,33] is coupled with microbial growth, which also needs NH 3 as a component for protein synthesis. The use of NH 3 for microbial synthesis caused the ammonia coefficients of determination for urease with amylase and protease in the CFRF fraction are 0.304 and 0.186, respectively.…”

Bioconversion of Methionine Supplemented Spent Sorghum Mash into Protein Biomassusing Rumen Liquor as Inoculum

“…Studies have shown that Sulphur supplementation has improved gain by 12% in steer grazing sorghum-Sudan grass containing 0.08-0.12% methionine (Anonymous, 1998). The similarity in %CP for all fermented methionine supplemented samples are in agreement with the findings of Brondani et al (1991), that the effect of methionine supplementation on bacteria protein synthesis from high fibre nitrogen (N) based diets will depend on its adjustment based on the N: S ratio. If the level of nitrogen in the diet remain low, the effect of increasing levels of S on bacteria protein synthesis will remain insignificant.…”

Sugarcane‐derived animal feed

“…Therefore, bagasse contributes little in the way of protein, lipids, and minerals to animal feed, and there are relatively few studies describing the incorporation of bagasse as roughage into animal feed without some form of processing to enhance digestibility , Romanponce et al 1975, Hegde et al 1982, Briceno et al 1987, Brondani et al 1991, Singh et al 2004. Despite this, while only a small proportion (<7.5%) of cattle in Brazil spend any significant period of time in feedlots, the size of the industry means that the sugarcane bagasse used as the primary source of roughage in finishing diets in a significant proportion (approximately 20%) of Brazilian feedlots represents a substantial amount (Oliveira and Millen 2014).…”