The effect of ensiled paulownia leaves in a high-forage diet on ruminal fermentation, methane production, fatty acid composition, and milk production performance of dairy cows

Table 8 The effect of replacing alfalfa silage with paulownia leaves silage (60 g/kg) on milk fatty acids (FA) composition (g/100 g FA) and desaturation (DI) of milk of dairy cows (n = 16) (Exp. 3)

Item^a	Treatment^b		SEM	P-value^c
Item^a	CON	PLS	SEM	P-value^c
Saturated FA
C8:0	0.94	0.92	0.01	0.41
C10:0	2.86	2.91	0.08	0.78
C12:0	3.80	3.75	0.07	0.76
C14:0	11.8	11.5	0.13	0.22
C15:0	1.46	1.59	0.02	< 0.01
C16:0	34.3	33.1	0.44	0.16
C18:0	11.5	11.6	0.13	0.65
Monounsaturated FA
C16:1	1.33	1.74	0.05	< 0.01
C18:1 trans-10	0.53	0.44	0.01	< 0.01
C18:1 trans-11	0.60	0.51	0.02	0.02
C18:1 cis-9	21.3	22.6	0.32	0.06
Polyunsaturated FA
C18:2 cis-9 cis-12	3.23	3.16	0.03	0.38
C18:2 cis-9 trans-11	0.56	0.72	0.01	< 0.01
C18:2 trans-10 cis-12	0.11	0.12	0.003	0.13
C18:3 cis-9 cis-12 cis-15	0.39	0.47	0.01	< 0.01
C20:4 n-6	0.13	0.16	0.002	< 0.01
C20:5 n-3	0.058	0.062	0.004	0.30
C22:6 n-3	0.051	0.057	0.002	0.19
Other FA^c	4.91	4.73	0.06	0.56
Total FA
Sum of SFA	67.9	66.2	0.39	0.04
Sum of UFA	32.1	33.8	0.39	0.04
Sum of MUFA	27.4	28.8	0.35	0.05
Sum of PUFA	4.66	4.90	0.05	0.03
Sum of n-6 FA	3.98	3.92	0.05	0.51
Sum of n-3 FA	0.51	0.60	0.01	< 0.01
Sum of trans-C18:1	1.69	1.53	0.02	< 0.01
Sum of MCFA	52.9	51.6	0.47	0.16
Sum of LCFA	43.2	44.6	0.47	0.18
PUFA/SFA ratio	0.07	0.08	0.001	0.02
n-6/n-3 FA ratio	7.89	6.76	0.12	< 0.01
DI C14:1/(C14:0 + C14:1)^d	0.28	0.30	0.004	0.01
DI C16:1/(C16:0 + C16:1)	0.037	0.051	0.002	0.02
DI C18:1/(18:0 + C18:1)	0.65	0.66	0.003	0.06
DI RA/(VA + RA)	0.48	0.59	0.01	< 0.01

^aSFA saturated fatty acids, UFA unsaturated fatty acids, MUFA monounsaturated fatty acids, PUFA, polyunsaturated fatty acids, MCFA medium-chain fatty acids, LCFA long-chain fatty acids, RA rumenic acid (C18:2 cis-9, trans-11), VA vaccenic acid (C18:1 trans-11)
^aCON control diet, PLS paulownia leaves silage diet
^bThe results are considered to be significantly different at P ≤ 0.05
^cOther FA include C14:1, C15:1. C17:0, C17:1, C18:1 trans-6–8, C18:1 trans-9, C18:1 cis-11, C18:1 cis-12, C18:1 cis-13, C18:1 cis-14, C19:0, C20:0, C20:1 trans, C18:3 n-6, C21:0, C20:2, C22:0, C20:3 n-6, C22:1 n-9, C20:3 n-3, C23:0, C22:2, C24:0 and C24:1
^dDI C14:1, DI C16:1, DI C18:1, DI RA/(VA + RA) were calculated according to Bryszak et al. [20]

ISSN: 2049-1891