Effects of different sources of carbohydrates on intake, digestibility, chewing, and performance of Holstein dairy cows

Table 2 Physical characteristics of three total mixed rations containing three different sources of non-fiber carbohydrate

Item	Treatments¹			SEM	P value
Item	B	BC	BB	SEM	P value
Particle size distribution (material retain on each sieve, % of DM)
19 mm	9.7	10.1	9.8	0.732	0.213
8 mm	22.2	22.1	20.4	0.912	0.133
1.18 mm	34.4	34.2	36.9	1.648	0.422
Pan	33.7	33.6	32.9	0.641	0.455
Geometric mean, mm	3.85	3.92	3.80	0.692	0.087
Standard deviation of geometric mean	1.20	1.24	1.34	0.106	0.093
Physical effective factor
pef_m²	66.2	66.3	66.9	0.509	0.101
pef _{> 8}³	34.4	34.6	31.3	0.322	0.288
pef _{> 1.18}⁴	66.3	66.4	67.1	0.694	0.083
Physical effective NDF, % of DM
peNDF_m	24	24	26	1.13	0.063
peNDF _{> 8}	12	13	12	1.03	0.054
peNDF _{> 1.18}	24	24	26	1.14	0.063

¹Treatments were diets containing barley + basal diet (B), barley and corn + basal diet (BC), and barley and beet pulp + basal diet (BB).
²pef_m = physically effective factor, based on DM retained on sieve 1.18 mm [13].
³pef_>8 = physically effective factor, determined as the proportion of DM retained on sieves of the original version of Penn State particle separator [10].
⁴pef_>1.18 = physically effective factor, determined as the proportion of DM retained on sieves of the new version of Penn State particle separator [11].
⁵The peNDF was calculated by multiplying NDF content of each portion on each sieve on each pef [13].

ISSN: 2049-1891