. 2019 Jun 16;9(6):359. doi: 10.3390/ani9060359

Table 3.

Effect of feeding glycerin on the ruminal environment of young bulls fed a high level of concentrate.

Item	Treatments ¹				Hours after Feeding				SEM ²	p-Value
Item	0 G	20 G	40 G	80 G	0 h	2 h	4 h	8 h	SEM ²	Treatment (G)	Hours (T)	GxT
pH	6.32 ^ab	6.38 ^a	6.14 ^b	5.74 ^c	6.73 ^a	6.03 ^b	5.74 ^c	6.09 ^b	0.183	<0.001	<0.001	0.164
NH₃-N (mg/100 mL)	3.39 ^a	2.32 ^b	3.51 ^a	3.78 ^a	3.82 ^b	5.12 ^a	2.08 ^c	1.98 ^c	0.385	0.019	<0.001	0.089
Lactic acid (mg/100 mL)	4.14	3.96	4.31	4.30	4.79 ^a	4.52 ^a	3.35 ^b	4.04 ^ab	0.402	0.919	0.012	0.388
Total VFA ³ (mM)	105.2 ^a	99.5 ^a	100.6 ^a	83.6 ^b	85.5 ^b	103.1 ^a	99.5 ^a	100.7 ^a	4.67	0.001	0.009	0.082
Molar proportion (%)
Acetic acid	60.5 ^a	61.0 ^a	58.3 ^b	52.8 ^c	62.9 ^a	56.6 ^bc	55.3 ^c	57.8 ^b	2.11	<0.001	<0.001	0.554
Propionic acid	24.1 ^c	26.7 ^b	29.0 ^a	29.7 ^a	23.8 ^b	28.4 ^a	29.5 ^a	27.6 ^a	3.24	<0.001	<0.001	0.614
Butyric acid	10.6 ^b	9.14 ^c	8.69 ^c	13.1 ^a	9.15 ^b	10.8 ^a	11.0 ^a	10.5 ^ab	1.46	<0.001	0.027	0.630
Isobutyric acid	0.52	0.36	0.43	0.27	0.62 ^a	0.36 ^b	0.24 ^b	0.35 ^b	0.073	0.062	0.005	0.052
Valeric acid	1.94 ^c	2.04 ^c	2.67 ^b	3.18 ^a	1.88 ^c	2.62 ^ab	2.95 ^a	2.39 ^bc	0.408	<0.001	0.003	0.966
Isovaleric acid	2.22 ^a	0.70 ^b	0.80 ^b	0.86 ^b	1.50	1.11	0.80	1.17	0.381	<0.001	0.280	0.963
Acetatic/propionic	3.03 ^a	2.55 ^b	2.13 ^c	1.96 ^c	2.96 ^a	2.20 ^b	2.11 ^b	2.40 ^b	0.425	<0.001	<0.001	0.951
(Acetatic+butyric)/propionic	3.62 ^a	2.93 ^b	2.46 ^c	2.44 ^c	3.41 ^a	2.64 ^b	2.55 ^b	2.86 ^b	0.542	<0.001	0.003	0.948

¹ Concentrate without glycerin, with 20, 40 or 80 g of glycerin per kg of dry matter (0 G, 20 G, 40 G and 80 G, respectively). ² SEM = standard error of the mean (n = 4 per treatment × 4 per post-feeding time). ³ VFA = Volatile fatty acids. ^a–c Means in the same row with different superscripts (within treatments or hours after feeding) are significantly different (p < 0.05).