Table 1. Ingredient and chemical composition of the experimental diets (%DM)
Item
|
Diet
|
BDU
|
BDL
|
BDCL
|
BDO
|
Ingredients, % of DM
|
|
|
|
|
Corn silage
|
20.07
|
20.07
|
20.07
|
20.07
|
Alfalfa hay
|
18.24
|
18.24
|
18.24
|
18.24
|
Wheat straw
|
0.73
|
0.73
|
0.73
|
0.73
|
Cottonseed, whole
|
7.36
|
7.36
|
7.36
|
7.36
|
Beet sugar pulp
|
1.87
|
1.87
|
1.87
|
1.87
|
Barley grain, ground
|
15.04
|
15.04
|
15.04
|
15.04
|
Corn grain, ground
|
14.63
|
14.63
|
14.63
|
14.63
|
Corn gluten meal
|
4.12
|
4.12
|
4.12
|
4.12
|
Soybean meal (solvent extracted)
|
6.17
|
6.17
|
6.17
|
6.17
|
Soybean seeds, whole, heated
|
3.43
|
3.43
|
3.43
|
3.43
|
Sunflower meal, solvent
|
0.91
|
0.91
|
0.91
|
0.91
|
Meat and bone, rendered
|
2.33
|
2.33
|
2.33
|
2.33
|
Canola meal, mesh. Extract
|
1.42
|
1.42
|
1.42
|
1.42
|
Corn germ
|
0.73
|
0.73
|
0.73
|
0.73
|
Wheat bran
|
0.32
|
0.32
|
0.32
|
0.32
|
Calcium soap of fatty acids
|
0.5
|
0.5
|
0.5
|
0.5
|
Salt
|
0.18
|
0.18
|
0.18
|
0.18
|
Calcium phosphate (Di)
|
0.41
|
0.41
|
0.41
|
0.41
|
Calcium carbonate
|
0.41
|
0.41
|
0.41
|
0.41
|
Magnesium oxide
|
0.09
|
0.09
|
0.09
|
0.09
|
Sodium bicarbonate
|
0.5
|
0.5
|
0.5
|
0.5
|
Vitamin & Mineral premix
|
0.5
|
0.5
|
0.5
|
0.5
|
Urea g/d/cow
|
60
|
-
|
-
|
-
|
Lactosylurea g/d/cow
|
-
|
60
|
-
|
-
|
Concentrated Lactosylurea g/d/cow
|
-
|
-
|
60
|
-
|
Optigen g/d/cow
|
-
|
-
|
-
|
60
|
Composition, % of DM
|
|
|
|
|
CP
|
17
|
17
|
17
|
17
|
RDP
|
10.7
|
10.7
|
10.7
|
10.7
|
RUP
|
6.3
|
6.3
|
6.3
|
6.3
|
NDF
|
31.1
|
31.1
|
31.1
|
31.1
|
ADF
|
23.1
|
23.1
|
23.1
|
23.1
|
NFC
|
41.9
|
41.9
|
41.9
|
41.9
|
Ca
|
1
|
1
|
1
|
1
|
P
|
0.6
|
0.6
|
0.6
|
0.6
|
NEL, Mcal/kg
|
1.66
|
1.66
|
1.66
|
1.66
|
Lys/Met g/d
|
3.12
|
3.12
|
3.12
|
3.12
|
BDU (basal diet + urea), BDL (basal diet+ lactosylurea (first method)), BDCL (basal diet+ concentrated lactosylurea (second method)), BDO (basal diet+ Optigen (commercial slow release NPN source))
Corn silage was 28.98% DM and (DM basis): 48.97% NDF and 6.84% CP.
Alfalfa hay contained (DM basis): 42.70% NDF and 14.17% CP.
Wheat straw contained (DM basis): 56.77% NDF and 2.9% CP.
Cottonseed, whole contained (DM basis): 74.5% NDF and 7.9% CP.
Beet sugar pulp contained (DM basis): 37.48% NDF and 7.97% CP.
Barley grain, ground contained (DM basis): 15.53% NDF and 11.51% CP.
Corn grain, ground contained (DM basis): 12.32% NDF and 8.57% CP.
Corn gluten meal contained (DM basis): 31.33% NDF and 58.85% CP.
Soybean meal (solvent extracted) contained (DM basis): 14.85% NDF and 44.88% CP.
Soybean seeds, whole, heated contained (DM basis): 21.83% NDF and 34.83% CP.
Sunflower meal, solvent (DM basis): 35.83% NDF and 29.72% CP.
Meat and bone, rendered (DM basis): 49.62% CP.
Canola meal, mesh. Extract (DM basis): 31.53% NDF and 30.11% CP.
Corn germ (DM basis): 53.07% NDF and 18.23% CP.
Wheat bran contained (DM basis): 31.86% NDF and 14.43% CP.
Table 2. Cumulative gas production of treatment samples (ml/g of DM) (p<0.05).
incubation hour
|
experimental diets
|
|
BDU
|
BDL
|
BDCL
|
BDO
|
SEM
|
P value
|
2
|
29.56
|
26.49
|
26.76
|
29.56
|
0.92
|
0.074
|
4
|
62.86
|
64.12
|
63.86
|
65.52
|
1.37
|
0.664
|
6
|
86.75b
|
94.22a
|
94.35a
|
95.42a
|
1.94
|
0.039
|
8
|
116.68b
|
127.48a
|
127.68a
|
128.42a
|
2.16
|
0.008
|
12
|
170.02b
|
186.62a
|
190.68a
|
189.47a
|
2.16
|
0.0001
|
24
|
206.10b
|
240.43a
|
246.43a
|
246.96a
|
2.08
|
0.0001
|
48
|
232.59c
|
254.46b
|
268.72a
|
264.46a
|
2.66
|
0.0001
|
72
|
242.64c
|
266.18b
|
284.44a
|
276.84a
|
2.97
|
0.0001
|
96
|
248.98c
|
273.04b
|
290.91a
|
283.58a
|
3.10
|
0.0001
|
A1, ml/g DM
|
230.99c
|
276.33b
|
286.28a
|
288.79a
|
1.78
|
0.0001
|
c2, h-1
|
0.103a
|
0.093b
|
0.090b
|
0.087b
|
0.003
|
0.0707
|
Lag3, h
|
0.88b
|
1.090a
|
1.109a
|
0.962b
|
0.041
|
0.0202
|
Within a column, means without a common superscript letter differ (P<0.05).
BDU (basal diet + urea), BDL (basal diet+ lactosylurea (first method)), BDCL (basal diet+ concentrated lactosylurea (second method)), BDO (basal diet+ Optigen (commercial slow release NPN source))
1A = asymptotic gas production (ml/g DM incubated);
2c = fractional rate of fermentation (h-1);
3Lag = lag time (h);
Table 3: Estimated gas production parameters (p<0.05).
Item
|
Experimental diets
|
BDU
|
BDL
|
BDCL
|
BDO
|
SEM
|
P value
|
ME (MJ/kg DM)
|
10.54c
|
11.61b
|
11.80a
|
11.82a
|
0.025
|
0.0001
|
NEl (Mcal/kg DM)
|
4.56c
|
5.35b
|
55.49a
|
5.50a
|
0.019
|
0.0001
|
OMD (% DM)
|
51.32c
|
58.11b
|
59.36a
|
59.45a
|
0.165
|
0.0001
|
SCFA (mmol/200mgDM)
|
0.91c
|
1.06b
|
1.08a
|
1.09a
|
0.0004
|
0.0001
|
Within a raw, means without a common superscript letter differ (P<0.05).
BDU (basal diet + urea), BDL (basal diet+ lactosylurea (first method)), BDCL (basal diet+ concentrated lactosylurea (second method)), BDO (basal diet+ Optigen (commercial slow release NPN source))
Table 4: In-vitro disappearance of dry matter and crude protein (p<0.05).
Within a column, means without a common superscript letter differ (P<0.05).
BDU (basal diet + urea), BDL (basal diet+ lactosylurea (first method)), BDCL (basal diet+ concentrated lactosylurea (second method)), BDO (basal diet+ Optigen (commercial slow release NPN source))
Table 5: Total volatile fatty acid and protozoa in rumen fluid (p<0.05).
item
|
Experimental diets
|
BDU
|
BDL
|
BDCL
|
BDO
|
P value
|
SEM
|
VFA (mmol/Lit)
|
30.96b
|
101.29a
|
104.44a
|
104.60a
|
0.0001
|
1.18
|
Protozoa (106 organisms/ml)
|
2.66c
|
4.06b
|
4.66a
|
4.80a
|
0.0001
|
0.13
|
Within a raw, means without a common superscript letter differ (P<0.05).
BDU (basal diet + urea), BDL (basal diet+ lactosylurea (first method)), BDCL (basal diet+ concentrated lactosylurea (second method)), BDO (basal diet+ Optigen (commercial slow release NPN source))
AOAC, 2005. Official methods of analysis of AOAC. Washington: AOAC.
Coleman, G.S., 1986. The metabolism of rumen ciliate protozoa. FEMS microbiology letters 39, 321-344.
Hermansen, J.E., 2003. Organic livestock production systems and appropriate development in relation to public expectations. Livestock production science 80, 3-15.
Jouany, J.-P., 1996. Effect of rumen protozoa on nitrogen utilization by ruminants. The Journal of nutrition 126, 1335S-1346S.
Orpin, C.G., 1984. The role of ciliate protozoa and fungi in the rumen digestion of plant cell walls. Animal Feed Science and Technology 10, 121-143.
Virtanen, A.I., 1966. Milk production of cows on protein-free feed. Science 153, 1603-1614.
Xin, H., Schaefer, D., Liu, Q., Axe, D., Meng, Q., 2010. Effects of polyurethane coated urea supplement on in vitro ruminal fermentation, ammonia release dynamics and lactating performance of Holstein dairy cows fed a steam-flaked corn-based diet. Asian-Australasian Journal of Animal Sciences 23, 491-500.
Zhang, H., Zhang, P., Ye, J., Wu, Y., Fang, W., Gou, X., Zeng, G., 2016. Improvement of methane production from rice straw with rumen fluid pretreatment: A feasibility study. International Biodeterioration & Biodegradation 113, 9-16.
Table 6 is not available with this version