Effects of dietary crude protein on the performance of ...
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DRMS. 2014. DHIA glossary. IDF. 2015. Bulletin 475/2015. NRC. 2001. National Research Council. Nutrient Requirements of Dairy Cattle. Vol. 7th rev. ed. Natl. Acad. Sci., Washington, D. Olmos-Colmenero and Broderick. 2006. Effect of dietary crude protein concentration on milk production and nitrogen utilization in lactating dairy cows. J.Dairy Sci. 89:1704-1712 Spek et al. 2013. Prediction of urinary nitrogen and urinary urea nitrogen excretion by lactating dairy cattle in northwest Europe and North America: A meta-analysis. J.Dairy Sci. 96:4310-4322. • Studies suggested that removal of excess dietary crude protein (CP) has no impact in milk production (Olmos-Colmenero et al. 2006). • High dietary CP is usually associated with higher feed cost and loss of excess nitrogen (N) in the urine as urinary urea-N (UUN). • Excess UUN excretion represents an environmental concern because urea-N in the manure contributes to ammonia volatilization, nitrate leaching, and nitrous oxide emission. • Milk urea nitrogen (MUN) is a monitoring tool to evaluate dietary CP and predict UUN (Spek et al. 2013). • Variation in MUN is not fully explained by dietary CP, suggesting individual differences among cows (Spek et al. 2013). • The ultimate goal is to formulate diets with the lowest possible dietary CP content to minimize UUN excretion, without penalizing cow performance. BACKGROUND • To evaluate performance and feed conversion efficiency in: • cows grouped as either high MUN cow (HMUNC) or low MUN cow (LMUNC; phenotypic basis) but similar parity, days in milk, and milk protein yield, and • fed diets with either 16.5 or 14.9% CP (dry matter basis); • To assess the interaction between dietary CP and cow phenotypic MUN. OBJECTIVE REFERENCES RESULTS • All cows were housed in a free-stall pen (Arlington Research Station.) • Dietary treatments were formulated with differential proportion of Soyhulls and Soy Plus (Table 2). • Individual cow dry matter intake (DMI) was recorded continuously using a roughage intake control e-gates system. RESULTS Effects of dietary crude protein on the performance of cows grouped based on high or low phenotypic milk urea nitrogen Paulina Letelier, Francisco Contreras-Govea, Benito Albarrán-Portillo, Fernanda de Kassia Gomes, and Michel A. Wattiaux Department of Dairy Science, University of Wisconsin-Madison Contact: [email protected] PDPW Business Conference, 2018 Group Item HMUNC 1 (n=9) LMUNC 1 (n=9) Parity 1.8±0.67 1.8±0.67 DIM 88.4±15.52 83.8±18.00 Milk protein, kg/d 1.4±0.22 1.4±0.21 MUN, mg/dL 15.5±1.48 12.2±1.28 Dietary CP, % of DM Group P-value Item 16.5 14.9 SEM HMUNC 1 LMUNC 1 SEM Diet Group Diet x Group DMI 2 , kg/d 27.8 27.4 0.93 27.4 27.8 1.27 0.55 0.80 0.50 MY 2 , kg/d 48.4 47.1 2.22 46.9 48.6 3.09 0.13 0.70 0.78 FPCM 2 , kg/d 41.4 41.3 2.61 42.2 40.5 2.59 0.99 0.66 0.78 ECM 2 , kg/d 45.8 45.7 2.09 46.6 44.9 2.85 0.94 0.69 0.79 Milk Composition Fat, % 3.15 3.34 0.19 3.46 3.04 0.22 0.11 0.21 0.45 Protein, % 2.79 2.87 0.05 2.87 2.80 0.06 0.12 0.39 0.56 Lactose, % 4.85 4.94 0.05 4.91 4.88 0.05 0.28 0.68 0.28 SNF, % 8.57 8.76 0.11 8.71 8.62 0.14 0.19 0.53 0.39 MUN, mg/dL 14.14 10.69 0.32 13.43 11.40 0.37 <0.01 <0.01 0.88 Milk components yield Fat, kg/d 1.52 1.55 0.10 1.62 1.44 0.12 0.60 0.32 0.47 Protein, kg/d 1.35 1.35 0.07 1.35 1.36 0.09 0.98 0.93 0.60 Lactose, kg/d 2.36 2.32 0.12 2.30 2.38 0.16 0.56 0.75 0.43 SNF, kg/d 4.16 4.12 0.20 4.08 4.19 0.28 0.69 0.78 0.49 MUN, g/d 6.86 5.00 0.34 6.35 5.51 0.45 <0.01 0.21 0.85 Feed efficiency kg of milk/kg of DMI 1.74 1.71 0.05 1.71 1.75 0.06 0.17 0.66 0.10 kg of FPCM/kg of DMI 1.18 1.14 0.03 1.11 1.20 0.04 0.09 0.16 0.49 kg of ECM/kg of DMI 1.65 1.66 0.04 1.70 1.62 0.05 0.77 0.31 0.59 MATERIAL & METHODS HMUNC (n=5) LMUNC 16.5% dietary CP MATERIAL & METHODS Dietary CP, % of DM Item 16.5 14.9 Ingredients 1 , % of DM CS 35.9 35.9 AS 18.0 18.0 Soyhulls 5.9 9.7 Soy Plus 13.2 8.9 Energy Booster 1.8 2.5 HMC 17.8 17.8 Canola Meal 5.2 5.0 Vitamin & minerals 2.3 2.3 Chemical composition, % of DM CP 16.5 14.9 RUP 2 7.6 6.4 RDP 2 8.9 8.5 Forage NDF 20.3 20.3 NDF 28.4 30.3 EE 5.6 6.0 Ash 8.7 8.5 Starch 3 25.6 25.6 • Reducing dietary CP from 16.5 to 14.9% decreased MUN without penalizing performance: DMI, milk production, FPCM, ECM, and yields of protein, fat and lactose. • Both groups of cows had the same performance but low MUN cows had lower MUN than high MUN cows. • Our results suggest that genetic selection could be applied for low MUN (and presumably low UUN excretion) without penalizing milk production and milk protein yield. CONCLUSIONS Crossover experimental design with 2 periods. The authors thank USDA AFRI award # 2011-68004-30340 and Wisconsin Alumni Research Foundation for funding, and Dairy Nutrition Plus (DNP) for donation of the SoyPlus used in this study. ACKNOWLEDGEMENTS 14.9% dietary CP 1 AS: Alfalfa Silage, CS: Corn Silage, DM: Dry Matter, EE: Ether Extract, HMC: High Moisture Corn, NDF: Neutral Detergent Fiber, CP: Crude Protein. 2 Predicted according to NRC (2001). 3 Predicted according to Spartan. 8 9 10 11 12 13 14 15 16 HMUNC LMUNC 16.5 Table 1. Characteristics of cows grouped by level of MUN (data collected three weeks prior to the initiation of the study). 1 HMUNC: High MUN cows, LMUNC: Low MUN cows. 14.9 Dietary CP, % DM Figure 1. MUN response as influenced by level of dietary CP (P < 0.01) in cows grouped as high MUN cows or low MUN cows (P < 0.01) showing no interaction between group and diet (P = 0.88). Table 2. Ingredients and chemical composition of the diets. MUN (mg/dL) 14.9% dietary CP 16.5% dietary CP Period 1 Period 2 LMUNC (n=4) HMUNC (n=4) LMUNC (n=5) Group P = 0.88 1 HMUNC: High MUN cows, LMUNC: Low MUN cows. 2 FPCM: Fat-Protein Corrected Milk (IDF, 2015), ECM: Energy Corrected Milk (DRMS, 2014), DMI: Dry Matter Intake, MY: Milk Yield. Table 3. Effect of dietary CP content on milk production, milk composition, and feed efficiency
Transcript of Effects of dietary crude protein on the performance of ...
DRMS. 2014. DHIA glossary. IDF. 2015. Bulletin 475/2015. NRC. 2001. National Research Council. Nutrient Requirements of Dairy Cattle. Vol. 7th rev. ed. Natl. Acad. Sci., Washington, D. Olmos-Colmenero and Broderick. 2006. Effect of dietary crude protein concentration on milk production and nitrogen utilization in lactating dairy cows. J.Dairy Sci. 89:1704-1712 Spek et al. 2013. Prediction of urinary nitrogen and urinary urea nitrogen excretion by lactating dairy cattle in northwest Europe and North America: A meta-analysis. J.Dairy Sci. 96:4310-4322.
• Studies suggested that removal of excess dietary crude protein (CP) has no impact in milk production (Olmos-Colmenero et al. 2006).
• High dietary CP is usually associated with higher feed cost and loss of excess nitrogen (N) in the urine as urinary urea-N (UUN).
• Excess UUN excretion represents an environmental concern because urea-N in the manure contributes to ammonia volatilization, nitrate leaching, and nitrous oxide emission.
• Milk urea nitrogen (MUN) is a monitoring tool to evaluate dietary CP and predict UUN (Spek et al. 2013).
• Variation in MUN is not fully explained by dietary CP, suggesting individual differences among cows (Spek et al. 2013).
• The ultimate goal is to formulate diets with the lowest possible dietary CP content to minimize UUN excretion, without penalizing cow performance.
BACKGROUND
• To evaluate performance and feed conversion efficiency in: • cows grouped as either high MUN cow (HMUNC) or low MUN
cow (LMUNC; phenotypic basis) but similar parity, days in milk, and milk protein yield, and
• fed diets with either 16.5 or 14.9% CP (dry matter basis); • To assess the interaction between dietary CP and cow phenotypic
MUN.
OBJECTIVE
REFERENCES
RESULTS • All cows were housed in a free-stall pen (Arlington Research Station.) • Dietary treatments were formulated with differential proportion of
Soyhulls and Soy Plus (Table 2). • Individual cow dry matter intake (DMI) was recorded continuously
using a roughage intake control e-gates system.
RESULTS
Effectsofdietarycrudeproteinontheperformanceofcowsgroupedbasedonhighorlowphenotypicmilkureanitrogen
Paulina Letelier, Francisco Contreras-Govea, Benito Albarrán-Portillo, Fernanda de Kassia Gomes, and Michel A. Wattiaux
Department of Dairy Science, University of Wisconsin-Madison Contact: [email protected] PDPW Business Conference, 2018
Group Item HMUNC1 (n=9) LMUNC1 (n=9) Parity 1.8±0.67 1.8±0.67 DIM 88.4±15.52 83.8±18.00 Milk protein, kg/d 1.4±0.22 1.4±0.21 MUN, mg/dL 15.5±1.48 12.2±1.28
Dietary CP, % of DM Group P-value
Item 16.5 14.9 SEM HMUNC1 LMUNC1 SEM Diet Group Diet x Group
DMI2, kg/d 27.8 27.4 0.93 27.4 27.8 1.27 0.55 0.80 0.50 MY2, kg/d 48.4 47.1 2.22 46.9 48.6 3.09 0.13 0.70 0.78 FPCM2, kg/d 41.4 41.3 2.61 42.2 40.5 2.59 0.99 0.66 0.78 ECM2, kg/d 45.8 45.7 2.09 46.6 44.9 2.85 0.94 0.69 0.79 Milk Composition Fat, % 3.15 3.34 0.19 3.46 3.04 0.22 0.11 0.21 0.45 Protein, % 2.79 2.87 0.05 2.87 2.80 0.06 0.12 0.39 0.56 Lactose, % 4.85 4.94 0.05 4.91 4.88 0.05 0.28 0.68 0.28 SNF, % 8.57 8.76 0.11 8.71 8.62 0.14 0.19 0.53 0.39 MUN, mg/dL 14.14 10.69 0.32 13.43 11.40 0.37 <0.01 <0.01 0.88 Milk components yield Fat, kg/d 1.52 1.55 0.10 1.62 1.44 0.12 0.60 0.32 0.47 Protein, kg/d 1.35 1.35 0.07 1.35 1.36 0.09 0.98 0.93 0.60 Lactose, kg/d 2.36 2.32 0.12 2.30 2.38 0.16 0.56 0.75 0.43 SNF, kg/d 4.16 4.12 0.20 4.08 4.19 0.28 0.69 0.78 0.49 MUN, g/d 6.86 5.00 0.34 6.35 5.51 0.45 <0.01 0.21 0.85 Feed efficiency kg of milk/kg of DMI 1.74 1.71 0.05 1.71 1.75 0.06 0.17 0.66 0.10 kg of FPCM/kg of DMI 1.18 1.14 0.03 1.11 1.20 0.04 0.09 0.16 0.49 kg of ECM/kg of DMI 1.65 1.66 0.04 1.70 1.62 0.05 0.77 0.31 0.59
MATERIAL & METHODS
HMUNC (n=5)
LMUNC
16.5% dietary
CP
MATERIAL & METHODS
Dietary CP, % of DM Item 16.5 14.9 Ingredients1, % of DM CS 35.9 35.9 AS 18.0 18.0 Soyhulls 5.9 9.7 Soy Plus 13.2 8.9 Energy Booster 1.8 2.5 HMC 17.8 17.8 Canola Meal 5.2 5.0 Vitamin & minerals 2.3 2.3 Chemical composition, % of DM CP 16.5 14.9 RUP2 7.6 6.4 RDP2 8.9 8.5 Forage NDF 20.3 20.3 NDF 28.4 30.3 EE 5.6 6.0 Ash 8.7 8.5 Starch3 25.6 25.6
• Reducing dietary CP from 16.5 to 14.9% decreased MUN without penalizing performance: DMI, milk production, FPCM, ECM, and yields of protein, fat and lactose.
• Both groups of cows had the same performance but low MUN cows had lower MUN than high MUN cows.
• Our results suggest that genetic selection could be applied for low MUN (and presumably low UUN excretion) without penalizing milk production and milk protein yield.
CONCLUSIONS Crossover experimental design with 2 periods.
The authors thank USDA AFRI award # 2011-68004-30340 and Wisconsin Alumni Research Foundation for funding, and Dairy Nutrition Plus (DNP) for donation of the SoyPlus used in this study.
ACKNOWLEDGEMENTS
14.9% dietary
CP
1AS: Alfalfa Silage, CS: Corn Silage, DM: Dry Matter, EE: Ether Extract, HMC: High Moisture Corn, NDF: Neutral Detergent Fiber, CP: Crude Protein.
2Predicted according to NRC (2001). 3Predicted according to Spartan.
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HMUNC LMUNC
16.5
Table 1. Characteristics of cows grouped by level of MUN (data collected three weeks prior to the initiation of the study).
1HMUNC: High MUN cows, LMUNC: Low MUN cows.
14.9 Dietary CP, % DM
Figure 1. MUN response as influenced by level of dietary CP (P < 0.01) in cows grouped as high MUN cows or low MUN cows (P < 0.01) showing no interaction between group and diet (P = 0.88).
Table 2. Ingredients and chemical composition of the diets.
MU
N (m
g/dL
)
14.9% dietary
CP
16.5% dietary
CP
Period 1 Period 2
LMUNC (n=4)
HMUNC (n=4)
LMUNC (n=5) Group P = 0.88
1HMUNC: High MUN cows, LMUNC: Low MUN cows. 2FPCM: Fat-Protein Corrected Milk (IDF, 2015), ECM: Energy Corrected Milk (DRMS, 2014), DMI: Dry Matter Intake, MY: Milk Yield.
Table 3. Effect of dietary CP content on milk production, milk composition, and feed efficiency
