Jugular arginine supplementation increases lactation performance and nitrogen utilization efficiency in lactating dairy cows

Table 4 Effects of arginine infusion on the absorption and utilization of nitrogen in lactating dairy cows

Items	Treatments^c			SEM	P-value
Items	Control	Arg group	Ala group	SEM	P-value
Dietary N intake, g/d	485.74	500.21	511.10	20.25	0.48
Fecal N, g/d	152.36	137.68	138.53	11.6	0.39
Absorption of dietary N, %	68.53	72.38	72.91	2.36	0.17
Milk protein N^d, g/d	121.47^b	140.12^a	126.30^b	4.92	0.01
NUE^e, %	25.01^ab	28.20^a	24.69^b	1.25	0.03

^a,bDifferent superscripts within a column represent significant differences (P < 0.05)
^cControl, saline; Arg group, saline + 9.42 g/L L-Arg; Ala group: saline + 19.31 g/L L-Ala
^dThe daily production of milk protein N was calculated after determination of milk protein using a 6.38 factor, in which N (g/d) = protein (g/d) × 6.38
^eNUE (nitrogen utilization efficiency) = milk protein N/dietary N intake

ISSN: 2049-1891