1. 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
(603)

2. 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)

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

4. 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)

5. 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

6. 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.

7. 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

8. 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

9. 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

10. Calan Gates: Individual Intake

11. Blood Sampling

12. Rumen Fluid Sampling

13. Methane Collection Device

14. 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

15. 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

16. 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

17. 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%

18. 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%

19. 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

20. 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

21. Sampling Procedures

22. Sampling Procedures

23. 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

24. 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

25. 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%

26. 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

27. 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%

28. 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

29. The GreenFeed System: Automated
measurements of methane and
carbon dioxide

30. The GreenFeed System

31. 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

32. 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

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