Adaptation to various sources of dietary sulfur by ruminants

Abstract

The objective of these experiments was to determine adaptation by ruminants to dietary sulfur. In Exp. 1, lambs (n = 54; BW = 33.6 ± 0.4 kg) were allotted to 3 treatments: 1) 0% added dietary S (0%S), 2) 0.2% added dietary S (0.2%S), or 3) 0.4% added dietary S (0.4%S). Sulfur was added to the diet as Na(2)SO(4). Lambs fed the 0.2%S and 0.4%S diets had greater (P < 0.01) ADG and G:F compared to those fed the 0%S diet. There was time × diet interaction (P < 0.01) on ruminal hydrogen sulfide gas (H(2)S) concentrations. Ruminal H(2)S was not detected in lambs fed 0%S at any time. Ruminal H2S were not affected (P > 0.19) by diet on d 1 or 8; however, H(2)S were greater (P < 0.01) for lambs fed 0.2%S and 0.4%S than for lambs fed 0%S on d 15, 22, and 29 (0.2% was 931, 846, and 1,131 mg/L and 0.4% was 975, 737, and 1,495 mg/L on d 15, 22, and 29, respectively). These data suggest it takes at least 29 d for peak ruminal H(2)S to occur after exposure to Na(2)SO(4). In Exp. 2, lambs (n = 66; BW = 51.1 ± 0.4 kg) were allotted to 3 treatments: 1) 60% dried distillers grains with solubles (DDGS), 2) corn-based diet with Na(2)SO(4), or 3) corn-based diet with H(2)SO(4). All diets were formulated to contain 0.4%S. Lambs fed Na(2)SO(4) had greater (P < 0.05) ADG, DMI, and G:F than those fed H(2)SO(4) or 60% DDGS. A time × diet interaction occurred (P < 0.01) for ruminal H(2)S. There was no difference (P = 0.82) in H(2)S of lambs on d 1. However, at d 14 and 27 lambs fed supplemental Na(2)SO(4) had the lowest H(2)S concentrations while lambs fed 60% DDGS had the greatest (P < 0.01 on both d); lambs fed H(2)SO(4) were intermediate and different than both. These data suggest that at the same dietary S concentration, acidic S sources increased H(2)S and decreased DMI and ADG. In Exp. 3, Angus cross calves (n = 72; average initial BW = 324 ± 3 kg) were allotted to 3 treatments: 1) corn-based control d 0 through 85 (0%DDGS), 2) gradual step up to 60% DDGS diet (20% DDGS d 0 to 6, 40% DDGS d 7 to 13, 50% DDGS d 14 to 20, and 60% DDGS d 21 to 85; Step-up), or 3) 60% DDGS d 0 to 85 (60%DDGS). Overall, cattle fed 0%DDGS had increased (P < 0.05) DMI and ADG compared with those fed 60%DDGS or Step-up, and G:F was not affected (P = 0.42) by dietary treatment. On d 14, ruminal H(2)S concentrations were greater (P < 0.01) for cattle fed 60%DDGS and Step-up than for those fed 0%DDGS, and they did not differ (P ≥ 0.22) between DDGS-containing diets. These data illustrate that source of S impacts ruminal S metabolism and that S from DDGS is more readily reduced than S from Na(2)SO(4) or H(2)SO(4).

Impacts of bunk management on steer performance and ruminal hydrogen sulfide concentrations in steers fed modified distillers grains with solubles

“…Including 50% MDGS in diets fed to steers in the current experiment increased ruminal H 2 S compared with steers fed 25% MDGS. The increased concentration of H 2 S exhibited when greater concentrations of MDGS are fed during dietary adaptation in the current experiment are similar to results reported in previous research with dried distillers grains plus solubles ( Neville et al 2011 , 2012 ; Drewnoski et al, 2012 ; Felix et al, 2014 ). The lack of interaction between bunk management and MDGS inclusion was possibly a result of decreased separation in DMI in experiment 2.…”

“…The transition period from roughage-based diets to grain-based diets is a critical time for rumen adaptation and the most likely time for increased occurrence of digestive upset in feedlot cattle ( Schwartzkopf-Genswein et al, 2003 ). The relationship between distillers gains inclusion and hydrogen sulfide (H 2 S) is reasonably well defined ( Neville et al, 2012 ; Felix et al, 2014 ) and links between dietary adaptation to high-concentrate diets and onset of polioencephalomalacia (PEM) have been proposed ( Drewnoski et al, 2014 ). Associations between feedlot arrival, ruminal H 2 S, and incidence of PEM have also been reported ( Loneragan et al, 2005 ).…”

Influence of sulfur on the fermentation characteristics of corn distiller's dried grains with solubles in in vitro culture

“…In the present study, DDGS with different sulfur sources produced various GP with different GP rate, indicating that its sulfur source exerted a significant effect on the in vitro fermentation efficiency, especially in the initial stage of fermentation. Consistently, Felix et al (2014) reported that the source of sulfur affected rumen sulfur metabolism and that sulfur from DDGS was more readily reduced than sulfur from Na 2 SO 4 . As one of the most important rumen metabolic pathway of sulfur, sulfate-reducing bacteria (SRB) play an important role in the reduction of sulfate to sulfide (Beauchamp et al 2008) and its reduction ability would be cut down if sulfate concentration is excessive (Coleman 1960).…”

“…Some investigations seem to show that the dietary sulfur source could affect rumen hydrogen sulfide production and animal productivity (Uwituze et al 2011b), while most are essentially explaining the influence of dietary pH value or buffering capacity rather than sulfur source on sulfur metabolism (Felix et al 2014;Wu et al 2015). There is rare literature concerning the effects of sulfur source (valence state) on the nutritional value of DDGS.…”