Feed Supplements to Organic Dairy Cows André Fonseca de Brito, Veterinarian, Ph.D. Assistant Professor of Organic Dairy Management Department of Biological Sciences University of New Hampshire andre.brito@unh.edu (603) 862-1341

Flaxseed Flaxseed is an oilseed rich in the -3 fatty acid α-linolenic acid, which can be transferred to milk and it has potential health benefits for humans (Caroprese et al., 2010; Zachut et al., 2010) Feeding flaxseed also has been shown to increase milk conjugated linoleic acids (CLA) (Glasser et al., 2008) In addition to potential human health benefits, flaxseed reduced methane emissions in previous research (Soder et al., 2012)

Fatty Acid Classes in Milk Fat Saturated fatty acids (SFA)  55 - 80% of total fatty acids Monounsaturated fatty acids (MUFA)  15 - 30% of total fatty acids Polyunsaturated fatty acids (PUFA)  3 - 6% of total fatty acids

Fatty Acid Classes in Milk Fat Saturated fatty acids (SFA)  No double bonds  Straight structure  Stack tightly, providing rigidity, thus making fats solid at room temperature Monounsaturated fatty acids (MUFA)  1 double bond  Double bond causes bend (or “kink”) structure  Occupy more space, thereby making a fat liquid >1 double bond Conjugated linoleic acids (CLA) -3 and -6 fatty acids Polyunsaturated fatty acids (PUFA)

Flaxseed supplementation Pasture Ecology and Management Milk quality -3 fatty acids CLA Profitability $ Animal health Reproduction Methane emissions Flaxseed supplementation Summer annuals Forage brassica Small grains Pasture Ecology and Management

Effects of Ground Flaxseed on Milk Production and Composition and Methane Emissions in Organic Jersey Cows André F. Brito (UNH), Kathy Soder (USDA-ARS), Jana Kraft (UVM), Brianna Isenberg (UNH), Tales Resende (Federal University of Minas Gerais-Brazil, Diego Oitschach (Federal University of Viçosa-Brazil), André Pereira (UNH), Melissa Rubano (USDA-ARS) Experiment 1: Twenty lactating organic Jersey cows received (% of diet DM): 0, 5, 10, or 15% of ground flaxseed during the winter season. Experiment 2: Twenty lactating organic Jersey cows received (% of diet dry ma): 0 or 10% of flaxseed during the grazing season.

Ingredient Composition of TMR Fed During the Winter Season Diets (% of flaxseed) Item 0% 5% 10% 15% ------------------% of diet DM------------------ Baleage 55.0 Grass hay 8.0 Ground flaxseed 0.0 5.0 10.0 15.0 Soybean meal 6.0 4.8 3.5 2.0 Roasted soybean Corn meal 27.0 23.3 19.7 16.0 Minerals & vitamins

Nutrient Composition of TMR Fed During the Winter Season Diets (% of flaxseed) Item 0% 5% 10% 15% DM, % of diet fresh matter 58.8 59.3 58.9 60.4 CP, % of DM 18.3 18.4 NDF, % of DM 45.6 46.2 45.9 ADF, % of DM 30.0 30.2 30.8 31.1 OM, % of DM 93.2 93.1 93.0 Crude fat, % of DM 3.8 5.0 5.7 7.4 NFC, % of DM 25.5 23.6 22.8 21.4 NEL, Mcal/lb of DM 1.37 1.42 1.44 1.48

Ground Flaxseed Nutrient Composition DM, % of fresh matter 89.1 CP, % of DM 22.8 NDF, % of DM 25.2 ADF, % of DM 16.3 OM, % of DM 96.5 Crude fat, % of DM 33.6

Calan Gates: Individual Intake

Blood Sampling

Rumen Fluid Sampling

Methane Collection Device

Milk production, lb/day Milk Production Reduced Linearly in Organic Dairy Cows Fed Incremental Levels of Ground Flaxseed During the Winter Season Milk production, lb/day Linear (P < 0.001) Quadratic (P = 0.25) SED = 0.75 lb/day

Dry matter intake, lb/day Dry Matter Intake Reduced Linearly in Organic Dairy Cows Fed Incremental Levels of Ground Flaxseed During the Winter Season Dry matter intake, lb/day Linear (P < 0.001) Quadratic (P = 0.33) SED = 0.64 lbs/day

Diets (% of ground flaxseed) Milk Composition in Organic Dairy Cows Fed Incremental Levels of Ground Flaxseed During the Winter Season Diets (% of ground flaxseed) Contrasts (P-value) 0% 5% 10% 15% SED1 Linear Quadratic Milk fat, % 4.59 4.58 4.62 4.65 0.10 0.49 0.78 Milk fat, lb/day 2.16 2.18 2.07 2.05 0.07 0.05 0.69 Milk protein, % 3.44 3.39 3.37 3.32 0.03 <0.001 0.97 Milk protein, lb/day 1.61 1.52 1.46 0.04 0.33 MUN, mg/dL 12.8 12.7 12.0 10.9 0.36 0.06 1SED = standard error of least square means difference

Milk CLA, % of total milk FA Milk CLA Increased Linearly in Organic Dairy Cows Fed Incremental Levels of Ground Flaxseed During the Winter Season Milk CLA, % of total milk FA Linear (P < 0.001) Quadratic (P < 0.01) SED = 0.10%

Milk -6 and -3, % of total milk FA Milk CLA Increased Linearly in Organic Dairy Cows Fed Incremental Levels of Ground Flaxseed During the Winter Season Milk -6 and -3, % of total milk FA Linear (P < 0.001) Quadratic (P < 0.01) SED = 0.04%

Methane emissions, lb/day Methane Emissions Reduced Linearly in Organic Dairy Cows Fed Incremental Dietary Levels of Ground Flaxseed During the Winter Season Methane emissions, lb/day Linear (P < 0.001) Quadratic (P = 0.25) SED = 0.75 lb/day

Diet Composition During the Grazing Season Ground Flaxseed Item 10% ------% of diet DM------ Pasture 40.0 TMR Baleage 25.0 Liquid molasses 1.9 Ground flaxseed 0.0 10.0 Organic grain meal 33.1 23.1

Sampling Procedures

Sampling Procedures

Milk production, lb/day Milk Production Reduced Numerically in Organic Dairy Cows Fed Ground Flaxseed During the Grazing Season Diet (P = 0.71) Month (P < 0.001) SED = 2.86 lb/day Milk production, lb/day 0% Flax diet = 40.1 lb/day 10% Flax diet = 39 lb/day

TMR Dry Matter Intake Reduced Significantly in Organic Dairy Cows Fed Ground Flaxseed During the Grazing Season Diet (P < 0.01) Month (P < 0.001) SED = 0.26 lb/day TMR intake, lb/day 0% Flax diet = 23.9 lb/day 10% Flax diet = 23.1 lb/day

Milk Fat Content Was Similar in Organic Dairy Cows Fed Diets With or Without Ground Flaxseed During the Grazing Season Diet (P = 0.81) Month (P = 0.59) SED = 0.25% Milk fat content, % 0% Flax diet = 4.23% 10% Flax diet = 4.17%

Milk Fat Yield Was Similar in Organic Dairy Cows Fed Diets With or Without Ground Flaxseed During the Grazing Season Diet (P = 0.79) Month (P < 0.01) SED = 0.11 lb/day Milk fat yield, lb/day 0% Flax diet = 1.68 lb/day 10% Flax diet = 1.65 lb/day

Milk Protein Content Was Similar in Organic Dairy Cows Fed Diets With or Without Ground Flaxseed During the Grazing Season Diet (P = 0.76) Month (P < 0.001) SED = 0.13% Milk protein content, % 0% Flax diet = 3.43% 10% Flax diet = 3.47%

Milk protein yield, lb/day Milk Protein Yield Was Similar in Organic Dairy Cows Fed Diets With or Without Ground Flaxseed Between During the Grazing Season Diet (P = 0.97) Month (P < 0.001) SED = 0.08 lb/day Milk protein yield, lb/day 0% Flax diet = 1.36 lb/day 10% Flax diet = 1.37 lb/day

The GreenFeed System: Automated measurements of methane and carbon dioxide

The GreenFeed System

Methane and Carbon Dioxide (CO2) Emissions During the Grazing Season in Cows Supplemented or not with Ground Flaxseed Ground Flaxseed Item 10% Methane, lb/day 0.66 ± 0.08 0.65 ± 0.10 CO2, lb/day 18.3 ± 2.2 19.2 ± 2.7 Number of visits 4,468 ± 2.3 4,341 ± 2.8

Take home message… Increasing ground flaxseed (i.e., from 0 to 15% of diet DM) reduced milk production and yields and contents of milk fat and milk protein during the winter season However, more dietary flaxseed improved milk fatty acid profile (i.e., more n-3 and CLA) and reduced methane emissions during the winter season In general, supplementing pasture with ground flaxseed (i.e., 10% of diet DM) did not negatively affected milk yield and composition but did not mitigate methane emissions

Acknowledgements Jana Kraft (UVM) Brito’s Lab Kathy Soder (ARS)