Table 4.

Effects of nitrate supplementation to ruminants on volatile fatty acid production, metHb, and methane reduction in vivo.

Author	Nitrate sourcea	Effects on volatile fatty acids produced (P < 0.05)				Administered	Animal	Max MetHb (%)	Methane effect (%)	% Dry matter intake	Highest amount supplementedb
		Total acids	Acetate	Propionate	Butyrate
Alaboudi and Jones, 1985	KNO3	No effect	Increased	Decreased	Decreased	Top dressed	Sheep	2.0	NMc	0.05	0.02480
Asanuma et al., 2015	KNO3	Decreased	Decreased	Decreased	Decreased	Top dressed	Goats	NM	−89	NM	0.00310
de Raphélis-Soissan et al., 2014	Ca(NO3)2	No effect	Increased	Decreased	NM	Top dressed	Sheep	45.0	19	2.0	0.00767
El-Zaiat et al., 2014	Ca(NO3)2:NH3NO3	Increased	Increased	No effect	Increased	Encapsulated	Lambs	1.0	−33	4.5	0.02110
Farra and Satter, 1971	KNO3:NaNO3	No effect	Increased	Decreased	Decreased	Top dressed	Sheep	2.0	NM	6.0	0.00510
Hulshof et al., 2012	Ca(NO3)2	No effect	No effect	No effect	No effect	Top dressed	Beef	NM	−32	2.5	0.00600
Lee et al., 2015a,b	Ca(NO3)2	No effect	No effect	No effect	No effect	Encapsulated	Beef	< 2.0	18	2.5	0.00844
Leng et al., 2012	KNO3	NM	NM	NM	NM	Top dressed	Beef	< 1.0	−29	6.0	0.01020
Li et al., 2012	Ca(NO3)2	No effect	Increased	No effect	Decreased	Top dressed	Sheep	< 1.0	−35	3.0	0.01150
Lund et al., 2014	Ca(NO3)2	No effect	No effect	No effect	No effect	Top dressed	Dairyd	NM	−31	0.7	0.00120
Newbold et al., 2014	Ca(NO3)2	NM	NM	NM	NM	Top dressed	Beef	>20	−30	3.0	0.00266
Nolan et al., 2010	KNO3	Decreased	Increased	Decreased	Decreased	Top dressed	Sheep	< 1.0	−23	4.0	0.00680
Pal et al., 2014	KNO3	No effect	No effect	Decreased	No effect	Top dressed	Sheepd	NM	NM	2.0	0.00600
Sar et al., 2004	NaNO3	Increased	Increased	Decreased	Decreased	Via cannula	Sheep	18.4	−50	n/ac	0.00580
Sar et al., 2005	NaNO3	No effect	Increased	No effect	Decreased	Via cannula	Sheep	2.0	−50	n/a	0.00580
Takahashi and Young, 1991	NaNO3	NM	NM	NM	NM	Via cannula	Sheepd	20.0	−86	n/a	0.00188
van Zijderveld et al., 2010	Ca(NO3)2	No effect	No effect	No effect	No effect	Top dressed	Lambs	7.0	−32	2.6	0.00805
van Zijderveld et al., 2011	Ca(NO3)3	NM	NM	NM	NM	Top dressed	Dairy	4.7	−16	1.0	0.00366
Velazco et al., 2014	Ca(NO3)2	NM	NM	NM	NM	Top dressed	Beef	3.0	−17	2.6	0.00960

^aKNO₃, potassium nitrate; Ca(NO₃)₂, calcium nitrate; Ca(NO₃)₂:NH₄NO₃, 50:50 calcium nitrate:ammonium nitrate; KNO₃:NaNO₃, 50:50 potassium nitrate:sodium nitrate; NaNO₃, sodium nitrate.

^bmol/kg body weight.

^cNM, not measured; n/a, not applicable.

^dAnimal were not previously adapted to nitrate additions.