Progress 09/01/10 to 08/31/13
Outputs
Target Audience: Dairy and environmental scientists, extension, dairy professionals, general public Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided? Several graduate students were trained throughout the duration of the project. Undergraduate students participated in various parts of the project and were exposed to animal research. How have the results been disseminated to communities of interest? Publications in scientific journals, professional magazines, scientific and extension meetings, popular press. What do you plan to do during the next reporting period to accomplish the goals? This project has been completed.
Impacts
What was accomplished under these goals?
Improving the efficiency of nitrogen utilization in dairy cows One experiment was conducted to test the hypothesis that His is an amino acid limiting milk production and milk protein synthesis in dairy cows fed metabolizable protein (MP)-deficient diets. The experiment was conducted for 12 wk with 48 Holstein cows. Following a 2-wk covariate period, cows were blocked by DIM and milk yield and randomly assigned to one of 4 diets, based on corn silage and alfalfa haylage: control, MP-adequate diet (AMP; MP balance: +9 g/d); MP-deficient diet (DMP; MP balance: -317 g/d); DMP supplemented with RPLys and RPMet (DMPLM); and DMPLM supplemented with an experimental RPHis preparation (DMPLMH). Milk N secretion as a proportion of N intake was greater for the DMP diets compared with AMP. Compared with AMP, dry matter intake (DMI) tended to be lower for DMP, but was similar for DMPLM and DMPLMH. Milk yield was decreased by DMP (35.2 kg/d), but was similar to AMP (38.8 kg/d) for DMPLM and DMPLMH (36.9 and 38.5 kg/d, respectively), paralleling the trend in DMI. Milk fat and true protein content did not differ among treatments, but milk protein yield was increased by DMPLM and DMPLMH compared with DMP and was not different from AMP. Supplementation of the DMP diets with RPAA increased plasma Lys, Met, and His. Two experiments were conducted to investigate the effect of dietary crude protein (CP) concentration on ammonia (NH3) and greenhouse gas (GHG; nitrous oxide, methane, and carbon dioxide) emissions from fresh dairy cow manure incubated in a controlled environment (Exp. 1) and from manure-amended soil (Exp. 2). Manure was prepared from feces and urine collected from lactating Holstein cows fed diets with 16.7% (DM basis; HighCP) or 14.8% CP (LowCP). HighCP manure had higher N content and proportion of NH3- and urea-N in total manure N. In Exp. 1, NH3 emitting potential (EP) was greater for HighCP compared with LowCP manure (9.20 vs. 4.88 mg/m2 per min, respectively). The 122 h cumulative NH3 emission tended to be reduced by 47% using LowCP compared with HighCP manure. The EP and cumulative emissions of GHG were not different between HighCP and LowCP manure. In Exp. 2, urine and feces from cows fed LowCP or HighCP diets were mixed and immediately applied to lysimeters (61 x 61 x 61cm; Hagerstown silt loam; fine, mixed, mesic Typic Hapludalf) at 277 kg N/ha application rate. The average NH3 EP (1.53 vs. 1.03 mg/m2 per min, respectively) and the area under the EP curve were greater for lysimeters amended with HighCP than with LowCP manure. The largest difference in the NH3 EP occurred approximately 24 h after manure application (approximately 3.5 times greater for HighCP than LowCP manure). The 100 h cumulative NH3 emission was 98% greater for HighCP compared with LowCP manure. The EP of methane was increased and that of carbon dioxide tended to be increased by LowCP compared with HighCP manure. The cumulative methane emission was not different between treatments, while the cumulative carbon dioxide emission was increased with manure from the LowCP diet. Nitrous oxide emissions were low in this experiment and did not differ between treatments. Feeding high and low quality forage with different rumen-degradable protein levels on nutrient utilization by dairy heifers This study was being done to determine the effects of manipulating the degradability of the protein fractions in heifers diets containing two dietary fiber quality levels with four combinations of rumen degradable protein (RDP) and rumen un-degradable protein (RUP). Our previous data suggest that forage utilization of the diet of heifers can be manipulated with different responses expected as the forage quality and degradability of the protein fraction of the diet changes. Therefore it was necessary asses the level that RDP to maximize microbial protein synthesis and animal performance when dairy heifers are limit-fed an optimal N and ME intake. Dairy heifers precision fed diets using higher quality forage had greater apparent total tract DM, N, and OM digestibility over low quality diets. Protozoa numbers tended to be higher in LQ diets and linearly increased consistently with RDP in both forage qualities. Increasing RDP on LQ and HQ had no effects in apparent digestibility of any measured parameter or N retention in dairy heifers. The substitution of corn and a slow-release urea source for canola and a by-pass amino acid source was an effective replacement that increased rumen protozoa numbers.
Publications
- Type:
Journal Articles
Status:
Accepted
Year Published:
2013
Citation:
Lee, C., G. W. Feyereisen, A. N. Hristov, C. J. Dell, J. Kaye, and D. Beegle. 2013. Effect of dietary protein concentration on utilization of dairy manure nitrogen for plant growth, leachate nitrate losses, and ammonia emissions from lysimeters. J. Environ. Qual. (accepted).
- Type:
Journal Articles
Status:
Published
Year Published:
2011
Citation:
Lascano, G. J., and A. J. Heinrichs. 2011. Effects of feeding different levels of dietary fiber through the addition of corn stover in nutrient utilization of dairy heifers precision-fed high and low concentrate diets. J. Dairy Sci. 94:3025-3036.
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Progress 09/01/11 to 08/31/12
Outputs
OUTPUTS: One experiment was conducted to test the hypothesis that His is an amino acid limiting milk production and milk protein synthesis in dairy cows fed metabolizable protein (MP)-deficient diets. The experiment was conducted for 12 wk with 48 Holstein cows. Following a 2-wk covariate period, cows were blocked by DIM and milk yield and randomly assigned to one of 4 diets, based on corn silage and alfalfa haylage: control, MP-adequate diet (AMP; MP balance: +9 g/d); MP-deficient diet (DMP; MP balance: -317 g/d); DMP supplemented with RPLys (AminoShure-L) and RPMet (Mepron; DMPLM); and DMPLM supplemented with an experimental RPHis preparation (DMPLMH). Milk N secretion as a proportion of N intake was greater for the DMP diets compared with AMP. Compared with AMP, dry matter intake (DMI) tended to be lower for DMP, but was similar for DMPLM and DMPLMH. Milk yield was decreased by DMP (35.2 kg/d), but was similar to AMP (38.8 kg/d) for DMPLM and DMPLMH (36.9 and 38.5 kg/d, respectively), paralleling the trend in DMI. Milk fat and true protein content did not differ among treatments, but milk protein yield was increased by DMPLM and DMPLMH compared with DMP and was not different from AMP. Supplementation of the DMP diets with RPAA increased plasma Lys, Met, and His. Two experiments were conducted to investigate the effect of dietary crude protein (CP) concentration on ammonia (NH3) and greenhouse gas (GHG; nitrous oxide, methane, and carbon dioxide) emissions from fresh dairy cow manure incubated in a controlled environment (Exp. 1) and from manure-amended soil (Exp. 2). Manure was prepared from feces and urine collected from lactating Holstein cows fed diets with 16.7% (DM basis; HighCP) or 14.8% CP (LowCP). HighCP manure had higher N content and proportion of NH3- and urea-N in total manure N. In Exp. 1, NH3 emitting potential (EP) was greater for HighCP compared with LowCP manure (9.20 vs. 4.88 mg/m2 per min, respectively). The 122 h cumulative NH3 emission tended to be reduced by 47% using LowCP compared with HighCP manure. The EP and cumulative emissions of GHG were not different between HighCP and LowCP manure. In Exp. 2, urine and feces from cows fed LowCP or HighCP diets were mixed and immediately applied to lysimeters (61 x 61 x 61cm; Hagerstown silt loam; fine, mixed, mesic Typic Hapludalf) at 277 kg N/ha application rate. The average NH3 EP (1.53 vs. 1.03 mg/m2 per min, respectively) and the area under the EP curve were greater for lysimeters amended with HighCP than with LowCP manure. The largest difference in the NH3 EP occurred approximately 24 h after manure application (approximately 3.5 times greater for HighCP than LowCP manure). The 100 h cumulative NH3 emission was 98% greater for HighCP compared with LowCP manure. The EP of methane was increased and that of carbon dioxide tended to be increased by LowCP compared with HighCP manure. The cumulative methane emission was not different between treatments, while the cumulative carbon dioxide emission was increased with manure from the LowCP diet. Nitrous oxide emissions were low in this experiment and did not differ between treatments. PARTICIPANTS: Dr. Alexander N. Hristov, Dr. Jud Heinrichs, and Dr. Gabriela Varga Virginia Ishler TARGET AUDIENCES: Academia, extension educators, dairy consultants, feed industry, and dairy producers. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
Data generated in this project showed that metabolizable protein-deficient diets, approximately 15% below NRC (2001) requirements, will likely decrease dry matter intake and milk yield in high-producing dairy cows. Supplementation of metabolizable protein -deficient diet with rumen-protected Lys and Met diminished the difference in dry matter intake and milk yield compared with the control, metabolizable protein-adequate diet. Additional supplementation with rumen-protected His eliminated the difference in dry matter intake and milk yield. Our data suggest that, similar to monogastric species, dietary amino acids play a role in feed intake regulation in dairy cows. Results from this project implicate His as a limiting amino acid in high-producing dairy cows fed corn silage and alfalfa haylage-based diets, deficient in metabolizable protein. The metabolizable protein -deficient diets clearly increased milk nitrogen efficiency and decreased dramatically urinary nitrogen losses. In a series of laboratory and greenhouse experiments, we demonstrated that manure from dairy cows fed a metabolizable protein-deficient diet had substantially lower ammonia emissions, compared with manure from cows fed a metabolizable protein-adequate diet. Due to a larger mass of manure applied to soil to meet plant nitrogen requirements, methane emissions from manure from the metabolizable protein-deficient diet had greater methane emissions compared with manure from the metabolizable protein-adequate diet.
Publications
- Lee, C., A. N. Hristov, T. W. Cassidy, K. S. Heyler, H. Lapierre, G. A. Varga, M. J. de Veth, R. A. Patton, and C. Parys. 2012. Rumen-protected lysine, methionine, and histidine increase milk protein yield in dairy cows fed metabolizable protein-deficient diet. J. Dairy Sci. 95:6042-6056.
- Lee, C., A. N. Hristov, K. S. Heyler, T. W. Cassidy, H. Lapierre, G. A. Varga, and C. Parys. 2012. Effects of metabolizable protein supply and amino acids supplementation on nitrogen utilization, production and ammonia emissions from manure in dairy cows. J. Dairy Sci. 95:5253-5268.
- Lee, C., A. N. Hristov, C. J. Dell, G. W. Feyereisen, J. Kaye, and D. Beegle. 2012. Effect of dietary protein concentration on ammonia and greenhouse gas emissions from dairy manure. J. Dairy Sci. 95:1930-1941.
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Progress 09/01/10 to 08/31/11
Outputs
OUTPUTS: A series of experiments investigated the effect of rumen-protected Lys (RPLys) and Met (RPMet) supplementation of a metabolizable protein (MP)-deficient diet in dairy cows. The first experiment was conducted for 12 weeks with 36 Holstein cows. Following a 2-week covariate period, cows were assigned to one of the following treatments: 15.6% CP diet [HighCP; metabolizable protein (MP) balance: +26 g/d], 14.0% CP diet (LowCP; MP balance: -313 g/d) supplemented with 100 g/cow/d of rumen-protected Lys (AminoShure-L, 24 g/d estimated digestible Lys supply), and 14.0% CP diet supplemented with rumen-protected Lys plus 24 g/cow/d RPMet (Mepron, 15 g/d estimated digestible Met supply; LowCPMet). DMI and milk yield were not affected by treatment. Compared with HighCP, LowCP decreased milk protein content (P = 0.02); with LowCPMet the effect was not significant (P = 0.07). The MP-deficient diets decreased urinary total and urea-N excretions and ammonia emission from manure. The second study investigated the effect of MP supply and RPLys and RPMet supplementation on amino acids recovery in milk protein in dairy cows. The experiment was conducted with 8 Holstein cows in a replicated 4x4 Latin square design trial. Treatments were similar to the first experiment. Lys, Met, His, EAA and total AA secretion in milk was not affected by diet. RPLys and RPMet supplementation decreased milk Lys and Met recoveries (milk/intake) compared with LowCP. Lys, His, EAA and total amino acid recoveries in milk were greater for the LowCP diets compared with HighCP. A study was conducted to determine the effects of manipulating the degradability of the protein fraction in limit-fed heifers diets containing three dietary fiber level within two F:C maintaining a constant level of RDP. Eight cannulated Holstein heifers were fed 2 levels of concentrate HC (45% forage) and LC (90% forage) and to a forage type sequence [33% of forage as an proportionally equal combination of grass hay and wheat straw HS, 67% corn silage CS (Low fiber; LF); 50% HS, 50% CS (Medium fiber; MF); and 67% HS, 33% CS (High fiber; MF)] within forage level administered according to a split-plot, 4x4 Latin square design (21-d periods). Increasing dietary fiber through HS while maintaining a consistent RDP decreased DM, OM, NDF, ADF and cellulose AD linearly. Microbial protein synthesis predicted from urinary purine derivatives decreased linearly with HS addition resulting in a linear decrease in N retention with HS addition, which was opposite to ruminal NH3N and BUN, reflecting the inefficiency in N utilization as more HS was added to the diets. Rumen fermentation parameters and DM and fractional passages (solid and liquid) rates support the reduction in digestibility, N retention and microbial protein synthesis observed as more dietary fiber is added to the rations of dairy heifers precision-fed a constant level of RDP. PARTICIPANTS: Dr. Alexander N. Hristov, Dr. Jud Heinrichs, Dr. Gabriela Varga, and Virginia Ishler TARGET AUDIENCES: Academia, extension educators, dairy consultants, feed industry, and dairy producers. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
Metabolizable protein (MP)-deficient diets, supplemented with rumen-protected Lys and Met maintained milk production similar to a metabolizable protein-adequate diet, except that protein concentration was significantly decreased without the supplementation of ruminally-protected Met. Nitrogen losses and ammonia emissions from manure were dramatically decreased with the MP-deficient diets. Supplementation with ruminally-protected Lys and Met reduced the apparent efficiency of utilization of total intake Lys and Met for milk protein secretion. The apparent efficiency of utilization of all dietary amino acids for milk protein secretion was increased by decreasing dietary protein intake. Increasing fiber levels in precision feeding heifer programs can be beneficial in increasing protein and dry matter digestibility. This can result in a 4-6 percent improvement in N utilization over traditional heifer diets.
Publications
- Lee, C., A. N. Hristov, K. S. Hyler, T. W. Cassidy, M. Long, B. A. Corl, and S. K. R. Karnati. 2011. Effects of dietary protein and coconut oil supplementation on nitrogen utilization and production in dairy cows. J. Dairy Sci. (In Press).
- Lascano, G. J. and A. J. Heinrichs. 2010. Nutrient utilization of different levels of dietary fiber to dairy heifers using controlled intakes of high and low concentrate diets. J. Dairy Sci. 88. E-Suppl. 1:516.
- Lascano, G. J. 2011. Optimizing nutrient utilization of a precision feeding system for dairy heifers using low and high forage diets. 2011. PhD. Thesis. The Pennsylvania State University, University Park, PA. 245 pp.
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