The Benefits of Adding Sulfur and Urea to a Concentrate Mixture on the Utilization of Feed, Rumen Fermentation, and Milk Production in Dairy Cows Supplemental Fresh Cassava Root

Table 5

Effect of sulfur and urea levels on total VFA and its molar proportions in dairy cows.

Item	Sulfur-1		Sulfur-2		SEM	value
	Urea-1	Urea-2	Urea-1	Urea-2		Sulfur	Urea	Sulfur  urea
Total VFA, mM
0 h prefeeding	107.10	106.90	106.90	106.80	0.23	0.259	0.406	0.406
4 h postfeeding	109.10^a	129.30^b	106.10^a	131.00^b	0.45	0.417	0.001	0.784
Acetic acid, mole/100 moles
0 h prefeeding	64.10	64.20	64.60	64.30	0.24	0.230	0.757	0.475
4 h postfeeding	62.20	62.20	62.10	62.00	0.27	0.563	0.754	0.893
Propionic acid, mole/100 moles
0 h prefeeding	25.00	25.20	25.10	25.30	0.34	0.746	0.592	0.971
4 h postfeeding	27.30	27.40	28.40	28.30	0.46	0.050	0.957	0.790
Butyric acid, mole/100 moles
0 h prefeeding	10.90	10.60	10.30	10.40	0.24	0.113	0.649	0.542
4 h postfeeding	10.50	10.50	10.50	11.80	0.42	0.069	0.884	0.706

Sulfur-1 and sulfur-2 = sulfur addition into concentrate at 10 g/kg DM and 20 g/kg DM. Urea-1 and urea-2 = urea addition into concentrate at 10 g/kg DM and 20 g/kg DM; SEM = standard error of mean; VFA = volatile fatty acid; sulfur  urea = interaction effect between sulfur and urea; ^a,bmeans in the same row with different superscript letters are accepted as significantly different ().