MANAGEMENT SYSTEMS TO IMPROVE THE ECONOMIC AND ENVIRONMENTAL SUSTAINABILITY OF DAIRY ENTERPRISES.

• Sponsoring Institution: National Institute of Food and Agriculture
• Project Status: REVISED
• Funding Source: HATCH
• Reporting Frequency: Annual
• Accession No.: 1017808
• Project No.: NH00670-R
• Multistate No.: NC-_old2042
• Project Start Date: Oct 1, 2018
• Project End Date: Sep 30, 2023

Project Director
Brito, AN.

Recipient Organization
UNIVERSITY OF NEW HAMPSHIRE
51 COLLEGE RD SERVICE BLDG 107
DURHAM,NH 03824

Performing Department
Agriculture, Nutrition and Food Systems

Non Technical Summary
Agriculture is under increasing scrutiny regarding its role in global greenhouse gas emissions. In the United States, enteric fermentation by ruminants is the largest source of anthropogenic methane emissions. Forage-based dairy systems have been particularly targeted due to greater methane emissions than confinement dairies. However, the growing season in the Northeast United States is relatively short and characterized by periods of low forage biomass production during early spring, mid-summer, and late fall. Brassicas, which include turnip, swede, rape, kale, and canola among other species have emerged as promising annual crops for fall grazing because of their high productivity and digestibility and decreased enteric methane emissions in vitro and in vivo. We are proposing to link ruminant nutrition and grazing energetics to fill knowledge gaps concerning animal and dietary factors underlining the methane mitigation potential of canola as a grazing forage for lactating dairy cows through the following objectives: (1) Measure milk production, methane emissions, and nutrient utilization changes, and (2) Quantify changes in heat production, energy use efficiency, and animal activity. We expect a 10% increase in milk production in cows grazing canola due to dietary energy partitioned to milk synthesis rather than methanogenesis. We also expect an increase of approximately 15% in the number of acres used for canola and other brassicas as fall grazing species due to project research and activities. We further expect an increased understanding of on the interactions between HP, energy use efficiency, and cow activity when grazing canola. Additional outcomes of our project consist of producers' adoption of practices to extend the grazing season while maximizing forage production and utilization.

Animal Health Component

100%

Research Effort Categories

Basic

50%

Applied

50%

Developmental

0%

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
302	3410	1010	100%

Knowledge Area
302 - Nutrient Utilization in Animals;

Subject Of Investigation
3410 - Dairy cattle, live animal;

Field Of Science
1010 - Nutrition and metabolism;

Keywords

brassicas

dairy cow

methane

heat production

pasture

Goals / Objectives
Optimize dairy cow performance and well-being by improving nutrition, forage utilization, technology, and management.

Project Methods
Sub-Objective 1: Measure milk production, CH4 emissions, and nutrient utilization changes in dairy cows grazing canola or fed conserved forage plus grain.Twenty mid-lactation Jersey cows housed at the UNH Burley-Demeritt Organic Dairy Research Farm will be assigned to 1 of 2 treatments as follows (diet dry matter basis): (1) 65% cool-season grass-legume mix baleage + 35% ground corn-soybean meal-based concentrate (n = 10 cows; control) or (2) 35% cool-seasongrass-legume mix baleage + 30% canola pasture +35% ground corn-soybean meal-based concentrate (n = 10 cows). All cows will be fed baleage plus concentrate twice daily in the barn with dry matter intake measured individually. Following the p.m. milking, cows assingned to the canola treatment will be moved to pasture in a strip grazing management system. Grazing of canola will initiate ~50 d after planting (late July) in 2 grazing rotations of 3 weeks each (6 weeks total). The experiment will be set up as a randomized complete block design with a 1-week covariate period (baseline data collection) followed by a 6-week of data collection over 2 grazing seasons (n = 40 cows). Cows will be milked twice daily with milk production recorded throughout the 8-week study. Data and samples will be taken during the last week of the covariate period and weeks 3 and 6 thereafter. Refusals will be collected daily, while canola, baleage, and concentrate samples weekly. Composite feed samples will be dried (55°C), ground (1-mm screen), and later analyzed for dry matter, ash, total-N, neutral and acid detergent fiber, glucosinolates, and minerals using wet chemistry and chromatographic methods by commercial laboratories. Milk samples will be collected during 4 consecutive milkings and analyzed for fat, true protein, lactose, and milk urea-N by mid-infrared reflectance spectroscopy in a commercial laboratory. Body weight and body condition score (scale 1-5) will be recorded during the last 3 d of the covariate and sampling periods (weeks 3 and 6).Cows will be fed 1 kg/d of a pelleted-grain containing chromium oxide for 10 consecutive days starting 5 d before each experimental sampling period. Fecal grab samples will be taken twice daily (a.m. and p.m.) during the last 5 d of the chromium dosing. Chromium oxide will be used as an extrinsic marker in combination with in vitro dry matter digestibility of feeds to estimate pasture intake, fecal output of dry matter, and apparent total-tract digestibility of nutrients. Fecal samples will be dried (55°C), ground (1-mm screen), and analyzed for chromium, dry matter, total-N, neutral and acid detergent fiber, and ash by commercial laboratories. Spot urine samples will be taken twice daily (a.m. and p.m.) for 2 consecutive days and analyzed for creatinine, allantoin, uric acid, urea-N, and total-N using colorimetric methods. Excretion of urinary metabolites will be calculated based on their concentration in the urine multiplied by the urinary volume. Urinary purine derivatives (allantoin + uric acid) will be used as intrinsic markers to estimate microbial protein synthesis. Methane and CO2 emissions will be measured using 2 portable, head-chamber units (GreenFeed system; C-Lock Inc.) throughout the 8-week study. The GreenFeed system operates by releasing a bait feed triggered by a radio frequency ear tag and the cow's head located inside the feed chamber resulting in accurate breath sampling and near real-time analysis of CH4 and CO2 emissions using built-in non-dispersive infrared gas sensors. Gas sampling will be conducted according to the voluntary visits of the cows to the GreenFeed units, usually 4 to 5 times daily. Data will be analyzed by the Mixed Model procedures of SAS (version 9.4) according to a randomized complete block design with repeated measures over time. Block (pair of cows), treatments, and week of sampling will be treated as fixed effects, and cow nested in treatment as the random effect. Cows will be used as the experimental unit, with the covariate term included in the model.Sub-Objective 2: Quantify heat production (HP), energy use efficiency, and activity in dairy cows grazing canola or fed conserved plus grain.The GreenFeed system (see above) equipped with an oxygen sensor will be used to quantify HP according to a modification of Brouwer's equation (Brouwer, 1965), as proposed by Kaufman et al. (2011) as follows:HP (MJ) = [(4.96 + 16.07 ÷ respiratory quotient) × CO2] ÷ 1,000Where respiratory quotient = CO2 ÷ O2, CO2 and O2 is the volumetric flux in L/d for CO2 expired and O2 consumed, respectively, and 4.96 and 16.07 are the energy constants for CO2 and O2, respectively (Brouwer, 1965; Ferrell and Oltjen, 2008).All cows will be fitted with leg accelerometers to record animal activity. This device will be attached by a belt to the left hind leg of each cow with leg position summarized in 15-min block intervals (4 Hz sampling rate). Leg positions are defined as lying, standing still, or moving, and will be recorded as mean fractions of the current minute spent in these states. The total time moving, and number of steps taken in each 15-min interval will be recorded. These data will be stored in the device and transferred to a computer via the IceQube Analyzer software.Sub-Objective 3: Deliver best management practices for producing environmentally-friendly milk through enhanced learning opportunities among producers, industry personnel, researchers, educators, students, and public via workshops, field days, and webinars.Our team will deliver outreach activities throughout the 3-year period in coordination with NC-2042 members and northeastern stakeholder' organizations including the Northeast Pasture Consortium, Northeast Organic Dairy Producers Alliance (NODPA), Wolfe's Neck Farm (Freeport, ME), and Organic Valley/CROPP. We are expecting to engage over 500 organic dairy producers across the Northeast through field days, workshops, videos, webinars, and publications. These outreach events will be publicized in advance at the following: 1) websites from UNH, the Northeast Pasture Consortium, and NODPA; 2) Email listservs hosted by universities and stakeholder groups including NODPA (membership of +800 organic dairy farmers) and Organic Valley's Forum (distribution to 1,800 co-op members); and 3) University extension mailing lists. In addition, short video-clips and webinars will be produced and delivered via media outlets such as UNH extension Facebook webpage, NHAES webpages, Twitter, and YouTube channels.

Progress 10/01/19 to 09/30/20

Outputs
Target Audience:We are directly serving organic and conventional dairy farmers across the Northeast region. We are also serving extension educators, industry personnel (e.g., organic milk processors, nutritionists), and the scientific and academic community (e.g., graduate and undergraduate students, and fellow scientists) in the region and beyond. Our team presented project results in scientific conferences, farmer-oriented symposiums and workshops, and webinars regarding the use of canola for grazing, milk iodine and human health, seaweed supplementation, use of legumes in organic dairy diets, and rumen-protected amino acids for lactating dairy cows. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?The project outreach and research components are advancing as planned. Outreach activities such as presentations, dairy produces meetings, field days, farm tours, videos, webinars, and popular-press articles featuring project results have been delivered in collaboration with University Extension. How have the results been disseminated to communities of interest?Project results have been disseminated to dairy farmers, dairy nutritionists, extension educators, dairy industry personnel, students, and the scientific community via popular-press articles, peer-reviewed papers, field days, professional meetings, producer conferences, videos, webinars, and workshops. What do you plan to do during the next reporting period to accomplish the goals?We are currently analyzing results from the second year of the canola grazing study including ruminal microbiome, methane emissions, and animal production performance.

Impacts
What was accomplished under these goals? Forage canola study: We aimed to evaluate the effect of canola as grazed herbage on ruminal fermentation and plasma amino acids (AA) in lactating dairy cows. Twelve multiparous and 6 primiparous mid-lactating Jersey cows were assigned to control (CTRL) or canola (CAN) diet in a randomized complete block design. Cows in the CTRL group were kept in confinement, while CAN cows stayed in the barn during the day and had access to canola pasture from 1800 to 0500 h. Diets were formulated to yield a 60:40 forage:concentrate ratio with 50% of the baleage replaced by canola herbage in the CAN diet. The experiment lasted 7 wk (2-wk covariate) with sample collection done during wk-3 and wk-5. Daily herbage allowance was set at 12 kg of DM/cow, and ruminal fluid was collected using a stomach tube. Diet by wk interactions were found for plasma urea N and ruminal NH3-N showing that CAN cows had greater values at wk-5 than wk-3, but no change was observed for the CRTL diet. Ruminal pH was lower in CAN, while total volatile fatty acids VFA concentration did not change. Cows in the CAN diet had greater ruminal propionate than those in the CTRL, possibly because of increased sugars and less fiber in canola herbage vs. baleage. The acetate:propionate ratio was lower in CAN than CTRL. Significant diet by wk interactions were found for ruminal acetate and butyrate showing that acetate decreased while butyrate increased from wk-3 to wk-5; however, these changes were greater in CAN than CTRL diet. Individual AA in plasma was not affected by diet, except Trp which was lower in CAN. Energy source and rumen-protected amino acids (AA) study: We aimed to investigate the interactions between energy source (starch vs. fat) and rumen-protected (RP) Met, Lys, and His (MLH) on performance, plasma AA, and energy utilization in dairy cows fed metabolizable protein-deficient diets. Sixteen multiparous Holstein cows were used in a replicated 4 × 4 Latin square with a 2 × 2 factorial arrangement of treatments. Treatments included high starch (HS), HS + RPMLH, reduced starch + RP-fat (RSF), and RSF + RPMLH. The HS diet contained 26% ground corn, while the RSF diet had 16% ground corn replaced with 15% soyhulls and 1.5% RP-fat (i.e., palmitic acid-enriched supplement). Dietary treatments had no effects on intake, milk yield, CH4 production, CH4 yield, and CH4 intensity. Likewise, heat production did not change across diets. However, feeding RSF diets improved feed efficiency and milk fat yield compared with HS diets. Concentration of milk fat increased but that of milk true protein decreased with RSF vs. HS diets. Both milk urea N and plasma urea N concentrations were greater and milk N efficiency was lower for RSF vs. HS diets. Supplemental RPMLH tended to improve milk true protein concentration. Feeding RSF diets elevated plasma concentrations of Arg, Ile, Thr, and Ala but reduced Leu relative to HS diets. Plasma Met and His increased with RPMLH. Seaweed supplementation study: Previous research showed that over 50% of organic dairies in the Northeast and upper Midwest US feed Ascophyllum nodosum meal (ASCO) known to be a rich source of iodine (I). We aimed to investigate the effects of different levels of ASCO on I metabolism in lactating dairy cows. Twenty organic-certified Jersey cows were assigned to treatments in a randomized complete block design. Treatments were fed as follows: 400 g/d of ASCO was fed during 3 wk [elevated-phase; period 1 (P1)] then dropped to 100 g/d for another 3 wk (stepdown-phase; P2) and completely removed from the diet during the last 3 wk of the trial (withdraw-phase; P3). Control (CON) cows received no ASCO. Milk, blood, and urine samples were collected on wk 3, 6, and 9. Additional milk samples were taken at 24, 48, 72, 96, and 168 h after ASCO supplementation was discontinued in the end of P2. Rate of milk I decline was estimated by regressing the natural log of milk I concentration on time of sampling using a nonlinear method for determining the slope in SAS. Diet by period interactions were observed for milk, plasma, and urine I concentrations, with cows fed ASCO showing greater values in P1 and P2 and no difference in P3. The slope of milk I decline over time was calculated as 0.76%/h according to the equation Y = 6.26 (±0.13) - 0.0076x (±0.0013). Overall, feeding 100-400 g/d of ASCO elevated milk I above recommended levels for humans, and about 48 h were needed to bring milk I below 500 μg/L. Retail milk iodine study: Previous research showed that over 50% of organic dairies in the Northeast and Upper Midwest US feed Ascophyllum nodosum meal known to be a rich source of iodine (I). Therefore, milk I concentration (MIC) in retail organic milk may be greater than that of conventional milk. Further, different feeding practices between organic and conventional dairies have been shown to seasonally change MIC, which can be also affected by processing method. A total of 299 samples of 2%-reduced fat organic [n = 96; ultra-high temperature (UHT), n = 62; pasteurized, n = 34] and conventional (n = 203; UHT, n = 25; pasteurized, n = 178) milk were purchased in selected grocery stores (n = 73) in June 2017 (summer) and March-April 2018 (spring) from the 11 northeastern states and Washington DC (n = 23 cities visited). Statistical analyses were done in JMP Pro 15.0.0 using a full factorial ANOVA model that included season (summer vs. spring), production system (conventional vs. organic), and milk processing (UHT vs. pasteurized) as independent variables, as well as interactions. A season by production system interaction was observed; while conventional milk tended to have greater MIC (388 ± 17 μg/L) than organic (341 ± 22 μg/L) during the summer, organic milk had increased MIC (515 ± 21 μg/L) compared with conventional milk (437 ± 16 μg/L) in the spring. This seasonal difference likely results from intake of I-binding goitrogens present in pasture that prevent the transfer of I into milk. UHT milk also had greater MIC (455 ± 16 μg/L) than pasteurized milk (386 ± 12 μg/L). Overall, season and processing appear to affect MIC as shown in previous research, and MIC was generally below the 500-μg/L threshold considered safe for consumers.

Publications

• Type: Journal Articles Status: Published Year Published: 2020 Citation: Brito, A. F. 2020. Assessing the potential of milk iodine intake to mitigate iodine deficiency in pregnant women of the United States via supplementation of Ascophyllum nodosum meal to dairy cows: A sensitivity analysis. J. Dairy Sci. 103:67986809.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Scuderi, R. A., Y-.W. Lam, D. B. Ebenstein, R. Tacoma, L. M. Cersosimo, J. Kraft, A. F. Brito, and S. L. Greenwood. 2020. Comparative analysis of the skim milk and milk fat globule membrane proteomes produced by Jersey cows grazing pastures with different plant species diversity. J. Dairy Sci. 103:74987508.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Pereira, A. B. D., D. C. Moura, N. L. Whitehouse, and A. F. Brito. 2020. Production and nitrogen metabolism in lactating dairy cows fed finely ground field peas plus soybean meal or canola meal with or without rumen-protected methionine supplementation. J. Dairy Sci. 103:3161-3176.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Razzaghi, A., R. Valizadeh, M. H. Ghaffari, and A. F. Brito. 2020. Liquid molasses interacts with buffers to affect ruminal fermentation, milk fatty acid profile, and milk fat synthesis in dairy cows fed high-concentrate diets. J. Dairy Sci. 103:4327-4339.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Brito, A. F., and L. H. P. Silva. 2020. Symposium Review: Comparisons of feed and milk nitrogen efficiency and carbon emissions in organic versus conventional dairy production systems. J. Dairy Sci. 103:57265739.
• Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Zang, Y., L. H. P. Silva, Y. Geng, M. J. Lange, N. Q. Dattolico, N. L. Whitehouse, M. Miura, M. A. Zambom, and A. F. Brito. 2020. Dietary energy source and rumen-protected amino acids: Effects on milk production and plasma amino acid concentrations in dairy cows. J. Dairy Sci. 103 (Suppl. 1): 137.
• Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Silva, L. H. P., Y. Zang, M. Ghelichkhan, Y. Geng, S. L. Dillard, K. J. Soder, and A. F. Brito. 2020. Ruminal metabolism and plasma amino acids in Jersey cows grazing forage canola. J. Dairy Sci. 103 (Suppl. 1): 154.
• Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Sacramento, J. P., L. H. P. Silva, D. C. Reyes, L. G. R. Pereira, and A. F. Brito. 2020. A meta-analysis to compare feed and milk N efficiency of Holstein and Jersey cows. J. Dairy Sci. 103 (Suppl. 1): 251.
• Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Zang, Y., L. H. P. Silva, Y. Geng, M. J. Lange, N. Q. Dattolico, N. L. Whitehouse, M. Miura, M. A. Zambom, and A. F. Brito. 2020. Dietary energy source and rumen-protected amino acids: Effects on CH4 emissions and heat production in lactating dairy cows. J. Dairy Sci. 103 (Suppl. 1): 252.
• Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Silva, L. H. P., A. T. O. Melo, S. F. Reis, B. P. Jackson, F. Evans, and A. F. Brito. 2020. Effects of Ascophyllum nodosum meal and monensin on ruminal fermentation and microbiota. J. Dairy Sci. 103 (Suppl. 1): 258.
• Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Silva, L. H. P., J. P. Sacramento, D. C. R. Gomez, Y. Geng, M. Ghelichkhan, S. L. Dillard, K. J. Soder, and A. F. Brito. 2020. Milk production and composition in Jersey cows grazing forage canola. J. Dairy Sci. 103 (Suppl. 1): 277.
• Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Reyes, D. C., E. A. Latham, L. H. P. Silva, B. J. Isenberg, and A. F. Brito. 2020. Effects of ground flaxseed on ruminal microbiome composition in Jersey cows during the grazing season. J. Dairy Sci. 103 (Suppl. 1): 292.
• Type: Theses/Dissertations Status: Published Year Published: 2020 Citation: Zang, Y. Effect of rumen-protected methionine, lysine, and histidine and levels and sources of energy on milk production and nutrient utilization in lactating dairy cows fed metabolizable protein-deficient diets. Ph.D. Thesis Dissertation, University of New Hampshire, April 17, 2020.
• Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Ghelichkhan, M., L. H. P. Silva, R. C. R. Tinini, J. G. Dessbesell, M. A. Zambom, and A. F. Brito. 2020. Comparison of milk iodine concentration between retail conventional and organic milk in the United States. J. Dairy Sci. 103 (Suppl. 1): 222.
• Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Snider, M. A., S. E. Ziegler, H. M. Darby, K. J. Soder, A. F. Brito, B. Beidler, S. Flack, S. L. Greenwood, and M. T. Niles. 2020. Evaluation of research needs and management practices on organic, grass-fed dairy farms in the United States. J. Dairy Sci. 103 (Suppl. 1): 236.
• Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Ghelichkhan, M., L. H. P. Silva, R. C. R. Tinini, J. G. Dessbesell, M. A. Zambom, and A. F. Brito. 2020. Effect of different levels of Ascophyllum nodosum meal on iodine metabolism in Jersey cows. J. Dairy Sci. 103 (Suppl. 1): 248.
• Type: Other Status: Published Year Published: 2020 Citation: Brito, A. F., M. J. Lange, and L. H. P. Silva. 2020. The key role of forage legumes in organic dairy diets: effects on your bottom line. NODPA News. Available at: https://nodpa.com/n/945/The-Key-Role-of-Forage-Legumes-in-Organic-Dairy-Diets-Effects-on-Your-Bottom-Line

Progress 10/01/18 to 09/30/19

Outputs
Target Audience:We are directly serving organic and conventional dairy farmers across the Northeast region. We are also serving extension educators, industry personnel (e.g., organic milk processors, nutritionists), and the scientific and academic community (e.g., graduate and undergraduate students, and fellow scientists) in the region and beyond. Our team presented project results in scientific conferences, farmer-oriented symposiums and workshops events, and delivered webinars regarding the use of canola for grazing, kelp meal supplementation, and rumen-protected amino acids for lactating dairy cows. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?The project outreach and research components are advancing as planned. Workshops and outreach activities such as presentations, dairy farm meetings, field days, farm tours, videos, webinars, and popular-press articles featuring project results have been delivered. How have the results been disseminated to communities of interest?Project results have been disseminated to dairy farmers, dairy nutritionists, extension educators, dairy industry personnel, students, and the scientific community via popular-press articles, peer-reviewd papers, field days, professional meetings, farmer conferences, videos, webinars, workshops, and field days. What do you plan to do during the next reporting period to accomplish the goals?We are currently analyzing results from the second year of the canola grazing study including ruminal microbiome, methane emissions, and animal production performance.

Impacts
What was accomplished under these goals? ?Forage canola study: Forage canola is an annual crop that can be used to extend the fall grazing season. Along with high mass yield, canola also has high dry matter (DM) digestibility and recent in vitro research showed decreased methane (CH4) production. We aimed to evaluate the effect of canola as a grazing resource on milk yield and enteric CH4 emissions in dairy cows. Twelve multiparous and 6 primiparous mid-lactating organic-certified Jersey cows were blocked by parity and, within block, assigned to 1 of 2 treatments (control = CTRL or canola = CAN) in a randomized complete block design. Cows in the CTRL group were fed indoors and had no access to pasture, while CAN cows stayed in the barn during the day and grazed at night (from 6 pm to 5 am). The experiment last 6 wk with samples collected during wk 3 and 5 and wk 0 used as baseline or covariate. Diets were formulated to yield a 60:40 forage-to-concentrate ratio. Daily herbage allowance was set at 7.5 kg of DM/cow. Cows in the CTRL group consumed 21 kg/d of DM intake. Estimated herbage DM intake (pre- minus post-grazing mass) averaged 3.2 kg/d and mean baleage plus concentrate DM intake was 15.5 kg/d in CAN cows. Milk yield was lower in CAN than CTRL diet (20.8 vs 22.3 kg/d; P < 0.01) due to decreased DM intake and increased energy expenditure for grazing. However, yields of 4% fat-corrected milk and energy-corrected milk and concentration and yield of milk fat did not differ between treatments. While milk protein concentration increased in CAN cows (P < 0.01), milk protein yield did not change. Cows grazing canola had elevated milk urea N concentration compared with those in the CTRL diet (13.5 vs. 11.1 mg/dL; P < 0.01) possibly because of greater concentration of soluble protein in canola (mean = 55%) vs. baleage (mean = 38.3%). Enteric CH4 production (415 vs. 469 g/d; P < 0.01) and intensity (15.0 vs 16.4 g/kg of energy-corrected milk) were lower in cows fed CAN vs. the CTRL diet, which may be associated with decreased DM intake and presence of glucosinolates in canola. Overall, forage canola has potential to be used for grazing during the fall season. Iodine and protein sources study: Kelp meal (KM) is a supplement made from the brown seaweed Ascophyllum nodosum known to bioaccumulate iodine (I). Therefore, feeding KM may result in milk I above the recommended concentration of 500 μg/L. Canola meal (CM) contains goitrogenic glucosinolates (GLS) that affect I distribution in tissues through competitive inhibition of iodide transportation by the Na-iodide symporter. Our goal was to assess the interactions between 2 sources of I and protein on production, I metabolism, and urinary excretion of nitrogenous metabolites. Sixteen multiparous Jersey cows were used in a factorial replicated 4 × 4 Latin square design (21-d periods). Diets were formulated to yield similar concentrations of crude protein and I and consisted (DM basis) of 55% baleage and 45% concentrate. Dietary crude protein and neutral detergent fiber concentrations averaged 18.5 and 35.6%, respectively. Experimental treatments were: 10% soybean meal (SBM) + 110 mg/d of ethylenediamine dihydroiodide (EDDI) or 114 g/d of KM and 12.5% CM + 110 mg/d of EDDI or 114 g/d of KM. Kelp contained 775 mg/kg of I. Data analysis included the main effects of protein and I source and interaction. Compared with CM, SBM significantly decreased DM intake (20.7 vs. 21.7 ± 0.82 kg/d) and milk urea N (10.4 vs. 12.9 ± 0.4 mg/dL) and increased milk yield (22.7 vs. 21.5 ± 0.81 kg/d), thus improving feed efficiency (1.19 vs. 0.99 ± 0.03 kg/kg). Milk N efficiency was also greater (P < 0.01) in SBM than CM cows. Reduced milk yield and milk urea N was likely caused by atypical concentrations of neutral detergent insoluble crude protein (23.6%) and acid detergent insoluble crude protein (15.5%) in the CM used. Concentrations of milk fat (5.44 vs. 5.08 ± 0.14%) and protein (3.64 vs. 3.52 ± 0.05%) were significantly greater in cows fed CM vs. SBM. Feeding KM significantly increased milk yield compared with EDDI (22.4 vs. 21.8 ± 0.81 kg/d), while DM intake tended (P = 0.09) to improve in KM cows. Although I intake was greatest in SBM and EDDI diets, the actual difference between treatments was small. The drop in the concentration and yield of milk I was more pronounced in cows fed CM plus KM than CM plus EDDI (RDP by I interaction). Cows fed CM had greater concentrations of plasma thyroid-stimulating hormone, triiodothyronine, and thyroxine than those fed SBM possibly in response to GLS found in CM. Milk I decreased below 500 μg/L only in CM plus KM diet, which was also linked to CM-GLS. Neither the protein nor the I source affected the urinary excretion of total purine derivatives. In contrast, urinary excretion of N (% of N intake) decreased (26.2 vs. 31.2 ± 1.92%; P < 0.05) with feeding CM rather than SBM diets. Outcome: SBM and KM increased DM intake and milk yield, and feeding SBM further improved feed and milk N efficiency. The fact that milk I did not drop below 500 μg/L with feeding CM plus EDDI was unexpected and requires further investigations. Rumen-protected amino acids and energy concentration study: Metabolizable protein (MP)-deficient diets have been shown to reduce N excretion of dairy cows. However, such diets may limit synthesis of milk and milk protein possibly due to deficiencies in essential amino acids (AA), particularly methionine, lysine, and histidine (MLH), insufficient energy supply or both. We aimed to investigate the interactions between rumen-protected (RP) MLH and starch level on performance, plasma AA concentration, and methane (CH4) emissions of dairy cows fed MP-deficient diets. Sixteen multiparous Holstein cows were used in a replicated 4 × 4 Latin square with 2 × 2 factorial arrangement of treatments. Each period lasted 21 d with 14 d for diet adaptation and 7 d for sample collection. Treatments included high-starch (HS), HS + RPMLH, reduced starch (RS), and RS + RPMLH diets. The basal diets consisted (DM basis) of 35.7% corn silage, 14.7% haylage, and 49.6% concentrate. Dietary energy level varied by replacing 30% ground corn with 20% beet pulp and 10% soyhulls. Dietary net energy of lactation, starch, and crude protein averaged 1.68 Mcal/kg, 34.4% and 16% for HS diets, and 1.59 Mcal/kg, 12.3% and 16.4% for RS diets, respectively. Smartamine M, Aji-Pro L, and an Ajinomoto prototype His product were supplemented to meet digestible MLH requirements. The GreenFeed system was used to measure gaseous fluxes. Compared with RS diets, feeding HS diets increased yields of milk (37.9 vs. 40.1 kg/d) and milk true protein (1.07 vs. 1.16 kg/d) and decreased DM intake (25.4 vs. 24.7 kg/d). Feed and milk N efficiency were greater in cows fed HS vs. RS diets. Concentration of milk true protein increased, while that of milk fat decreased with HS vs. RS diets. Both milk urea N and plasma urea N were lowered for HS vs. RS diets. Supplementation of RPMLH improved milk true protein concentration. Starch level by RPMLH interactions were observed for plasma Arg and Lys, with elevated values in cows fed RS diets. Increased dietary energy reduced the plasma concentrations of all essential AA except Met and Thr. Plasma Met and His were increased by RPMLH. Daily CH4 production (434 vs. 545 g/d), yield (17.7 vs. 21.6 g/kg of DM intake), and intensity (10.7 vs. 13.6 g/kg of energy-corrected milk) were lower with feeding HS vs. RS diets, respectively. Consequently, cows fed HS diets had reduced CH4 energy losses than those fed RS diets (5.72 vs. 7.19 Mcal/d). Impact:enhanced dietary energy by replacing fibrous byproducts with ground corn improved yields of milk and milk protein through better use of dietary N and elevated mammary uptake of essential AA.

Publications

• Type: Journal Articles Status: Published Year Published: 2019 Citation: Antaya, N. T., M. Ghelichkahan, A. B. D. Pereira, K. J. Soder, and A. F. Brito. 2019. Production, milk iodine, and nutrient utilization in Jersey cows supplemented with the brown seaweed Ascophyllum nodosum (kelp meal) during the grazing season. J. Dairy Sci. 102:80408058.
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Zang, Y., L. H. P. Silva, M. Ghelichkhan, M. Miura, N. L. Whitehouse, M. L. Chizzotti, and A. F. Brito. 2019. Incremental amounts of rumen-protected histidine increase plasma and muscle histidine concentrations and milk protein yield in dairy cows fed a metabolizable protein-deficient diet. J. Dairy Sci. 102:4138-4154.
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Brito, A. F., and Y. Zang. 2019. A Review of lignan metabolism, milk enterolactone concentration, and antioxidant status of dairy cows fed flaxseed. Molecules. 24:E41 doi:10.3390/molecules24010041.
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Isenberg, B. J., K. J. Soder, A. B. D. Pereira, R. Standish, and A. F. Brito. 2019. Production, milk fatty acid profile, and nutrient utilization in grazing dairy cows supplemented with ground flaxseed. J. Dairy Sci. 102:4138-4154.
• Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Ghedini, C. P., A. F. Brito, K. Krieger, and G. Tempera. 2018. Milk enterolactone concentration in response to sucrose and flaxseed oil supplementation to dairy cows fed flaxseed meal. J. Dairy Sci. (Suppl. 2) 101:107.
• Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Sales, D. C., A. H. N. Rangel, L. H. F. Borba, S. A. Urbano, A. F. Brito, J. G. B. Galv�o Jr., H. Tonhati, E. G. Silva1, A. R. Freitas, and D. M. Lima Jr. 2018. Effects of composition, processing, and recovery of buffalo milk solids on the yield of mozzarella cheese. J. Dairy Sci. (Suppl. 2) 101:238.
• Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Hafla, A. N., K. J. Soder, A. F. Brito, R. Kersbergen, A. F. Benson, H. M. Darby, M. D. Rubano, S. L. Dillard, J. Kraft, and S. F. Reis. 2018. Winter supplementation of ground whole flaxseed impacts milk fatty acid composition on organic dairy farms in the northeastern United States. In: Proceedings of the 2018 American Forage and Grassland Council, Louisville, KY
• Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Silva, L. H. P., Y. Zang, M. Ghelickhan, Y. C. Geng, E. M. Meyer, and A. F. Brito. 2019. Milk yield and CH4 emission in Jersey cows grazing forage canola. J. Dairy Sci. (Suppl. 1) 102:105.
• Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Zang, Y., L. H. P. Silva, Y. Geng, M. Ghelichkhan, N. L. Whitehouse, M. Miura, and A. F. Brito. 2019. Effects of dietary starch level and rumen-protected AA on milk production and plasma AA concentration in dairy cows. J. Dairy Sci. (Suppl. 1) 102:166.
• Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Zang, Y., L. H. P. Silva, Y. Geng, M. Ghelichkhan, N. L. Whitehouse, M. Miura, and A. F. Brito. 2019. Dietary starch level and rumen-protected amino acids: Effects on CH4 emissions and heat production in lactating dairy cows. J. Dairy Sci. (Suppl. 1) 102:244.
• Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Brito, A. F., and L. H. P. Silva. 2019. Current and future trends of organic dairy in the United States: From feed efficiency to carbon emission. J. Dairy Sci. (Suppl. 1) 102:303.
• Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Ghelichkhan, M., R. C. R. Tinini, J. G. Dessbesell, H. A. Whitesel, Y. Zang, L. H. P. Silva, M. A. Zambom, and A. F. Brito. 2019. Effect of kelp meal on milk yield, methane emission, and thyroid hormones in Jersey cows. J. Dairy Sci. (Suppl. 1) 102:376.
• Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: LeCuyer, C. A., O. M. Gorman, M. Ghelichkhan, R. C. R. Tinini, J. G. Dessbesell, M. A. Zambom, and A. F. Brito. 2019. Body weight and skeletal growth in pre-weaned dairy calves fed organic-certified milk replacer. J. Dairy Sci. (Suppl. 1) 102:65.
• Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Ghelichkhan, M., D. Williams, L. H. P. Silva, and A. F. Brito. 2019. Interactions between iodine and protein sources: Effects on milk yield, milk components, and urinary N excretion in Jersey cows. J. Dairy Sci. (Suppl. 1) 102:68.
• Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Ghelichkhan, M., D. Williams, L. H. P. Silva, and A. F. Brito. 2019. Interactions between iodine and protein sources: Effects on milk iodine and thyroid hormones in Jersey cows. J. Dairy Sci. (Suppl. 1) 102:69.