Effect of soil contamination and additives on fermentative profile, microbial community and iron bioaccessibility of alfalfa silage

Chemical and Biological Technologies in Agriculture

Table 2 The total and bioaccessible iron contents of alfalfa silage

Item	Soil levels (%)	Additives			SEM	Significance
Item	Soil levels (%)	Con	LP	MLP	SEM	S	A	S × A
Total iron (µg g⁻¹ DM)	0	629.0^B ± 101.7	570.0^B ± 54.2	606.0^C ± 79.5	99.733	< 0.001	0.033	0.079
	1.5	1180.5^B ± 101.3	1150.4^B ± 130.0	1512.9^B ± 83.2
	7.5	4154.6^A ± 580.3	2811.4^A ± 323.6	4476.2^A ± 205.0
Ruminal iron (µg g⁻¹ DM)	0	37.3^bC ± 1.1	117.7^aC ± 3.6	117.8^aC ± 8.9	3.768	< 0.001	< 0.001	< 0.001
	1.5	59.3^bB ± 1.7	194.4^aB ± 3.5	209.3^aB ± 10.2
	7.5	121.7^cA ± 4.6	238.6^bA ± 10.4	344.6^aA ± 20.6
Abomasal iron (µg g⁻¹ DM)	0	4.7^bC ± 0.1	112.2^aB ± 4.9	115.6^aB ± 4.0	5.746	< 0.001	< 0.001	0.017
	1.5	44.8^bB ± 3.9	128.4^aB ± 2.2	134.0^aB ± 6.6
	7.5	63.0^bA ± 0.7	249.2^aA ± 7.4	272.6^aA ± 40.3
Intestinal iron (µg g⁻¹ DM)	0	11.5^cB ± 0.1	50.1^bB ± 0.3	101.4^aC ± 4.5	2.160	< 0.001	< 0.001	< 0.001
	1.5	37.3^cA ± 2.6	76.6^bA ± 8.7	164.4^aB ± 3.6
	7.5	42.3^cA ± 2.0	89.4^bA ± 0.7	253.6^aA ± 11.5
Dialyzable iron (µg g⁻¹ DM)	0	6.4 ± 0.1	10.0 ± 2.3	19.8^C ± 4.2	2.097	0.007	< 0.001	0.288
	1.5	7.6^b ± 1.7	28.3^ab ± 8.4	35.8^aB ± 2.8
	7.5	10.5^b ± 1.7	30.6^ab ± 11.4	50.9^aA ± 1.0

DM, dry matter
Con, control; LP, Lactobacillus plantarum inoculant alone; MLP, combination addition of molasses and Lactobacillus plantarum inoculant
SEM, error of the means; S, soil contamination levels; A, additives; S × A, interaction between soil contamination levels and additives; Means within the same row (a,b) or within the same column (A, B) with different superscript differ significantly from each other