Daytime Grazing in Mountainous Areas Increases Unsaturated Fatty Acids and Decreases Cortisol in the Milk of Holstein Dairy Cows
Abstract
:Simple Summary
Abstract
1. Introduction
2. Materials and Methods
2.1. Experimental Animals and Treatment Application
2.2. Analyses
2.2.1. Feed Samples and Analysis
2.2.2. Milk Collection and Analyses
2.2.3. Milk Composition
2.2.4. Fatty Acid Profiles of Milk Samples
2.2.5. Milk Cortisol Analysis
2.3. Statistical Analysis
3. Results
3.1. Dry Matter Intake, Milk Yield, and Milk Composition
3.2. Milk Fatty Acids
4. Discussion
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Item | Control | 12 hG | 24 hG |
---|---|---|---|
Days in milk | 110.5 ± 12.5 | 121.5 ± 20.1 | 117.6 ± 18.7 |
Milk yield (kg) | 33.5 ± 1.9 | 32.0 ± 2.5 | 31.8 ± 3.1 |
Body weight (kg) | 595 ± 27.5 | 575 ± 21.5 | 600 ± 31.5 |
Parity | 2 | 2 | 2 |
Item | TMR | Concentrate |
---|---|---|
Dry matter | 70.1 ± 35 | 92.5 ± 1.51 |
Ash | 8.3 ± 1.3 | 2.9 ± 0.33 |
Crude protein | 15.5 ± 1.2 | 12.9 ± 0.53 |
Neutral detergent fiber | 45.3 ± 2.7 | 13.7 ± 2.37 |
Acid detergent fiber | 23.9 ± 2.1 | 3.7 ± 0.35 |
Item | Sample 1 | Sample 2 | Sample 3 | Sample 4 | Average |
---|---|---|---|---|---|
% of DM | |||||
Ash | 7.3 | 9.5 | 6.5 | 8.7 | 7.9 ± 0.5 |
Crude protein | 13.1 | 11.5 | 11.7 | 10.5 | 11.7 ± 0.5 |
Neutral detergent fiber | 50.3 | 53.5 | 51.7 | 49.1 | 51.2 ± 1.3 |
Acid detergent fiber | 30.1 | 29.9 | 31.5 | 27.9 | 30.0 ± 1.5 |
Item | Treatment Groups | SEM | Significance Level | ||
---|---|---|---|---|---|
Control | 12 hG | 24 hG | |||
DMI, kg/d | 21.69 ± 0.83 a | 20.85 ± 1.15 ab | 16.83 ± 1.41 c | 1.013 | * |
Yield, kg/d | |||||
Actual milk | 32.35 ± 1.23 a | 29.33 ± 1.55 ab | 20.13 ± 2.05 c | 1.631 | ** |
3.5% FCM | 32.73 ± 1.23 a | 30.65 ± 1.43 ab | 23.15 ± 1.71 c | 1.193 | * |
Milk composition, % | |||||
Fat | 3.57 ± 0.08 c | 3.95 ± 0.11 b | 4.15 ± 0.17 a | 0.130 | *** |
Protein | 3.11 ± 0.05 ab | 3.35 ± 0.06 a | 2.95 ± 0.07 c | 0.053 | ** |
Lactose | 4.21 ± 0.13 ab | 4.39 ± 0.11 a | 4.05 ± 0.11 c | 0.031 | * |
SCC (×1000 cells/mL) | 120.80 ± 16.13 c | 165.30 ± 21.33 b | 205.30 ± 20.81 a | 19.501 | * |
Item | Treatment Groups | SEM 3 | Significance Level | ||
---|---|---|---|---|---|
Control | 12 hG | 24 hG | |||
Total fatty acids (g/100 mL) | |||||
SFA | 84.49 ± 1.06 a | 78.13 ± 1.07 b | 80.30 ± 1.01 b | 1.012 | * |
MUFA | 10.15 ± 0.81 b | 13.33 ± 0.51 a | 13.63 ± 0.45 a | 1.321 | * |
PUFA | 6.36 ± 0.83 b | 9.54 ± 0.53 a | 6.07 ± 0.67 b | 1.125 | * |
Total UFA | 16.51 ± 1.01 c | 21.87 ± 1.12 a | 19.70 ± 1.03 b | 1.027 | * |
SFA/UFA | 5.11 ± 0.11 a | 3.57 ± 0.13 b | 4.07 ± 0.12 b | 0.582 | ** |
Fatty acids (mg/100 g) | |||||
Linoleic acid | 2.32 ± 0.02 c | 2.97 ± 0.01 ab | 3.13 ± 0.03 a | 0.161 | * |
γ-linolenic acid | 1.13 ± 0.10 | 0.93 ±0.08 | 1.19 ±0.11 | 0.183 | ns |
Arachidonic acid | 3.33 ± 0.18 | 2.57 ± 0.08 | 2.41 ± 0.06 | 0.427 | ns |
Total ω-6 | 7.013 | 6.923 | 6.75 | 0.513 | ns |
α-linolenic acid | 0.21 ± 0.03 b | 0.49 ±0.03 a | 0.37 ± 0.03 b | 0.051 | *** |
EPA | 0.86 ± 0.05b | 1.03 ± 0.03 a | 0.73 ± 0.05 ab | 0.041 | ** |
DHA | 0.43 ± 0.07 b | 0.81 ± 0.03 a | 0.55 ± 0.05 ab | 0.027 | ** |
Total ω-3 | 1.51 b | 2.38 a | 1.68 b | 0.123 | ** |
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Ghassemi Nejad, J.; Lee, B.-H.; Kim, J.-Y.; Sung, K.-I.; Lee, H.-G. Daytime Grazing in Mountainous Areas Increases Unsaturated Fatty Acids and Decreases Cortisol in the Milk of Holstein Dairy Cows. Animals 2021, 11, 3122. https://doi.org/10.3390/ani11113122
Ghassemi Nejad J, Lee B-H, Kim J-Y, Sung K-I, Lee H-G. Daytime Grazing in Mountainous Areas Increases Unsaturated Fatty Acids and Decreases Cortisol in the Milk of Holstein Dairy Cows. Animals. 2021; 11(11):3122. https://doi.org/10.3390/ani11113122
Chicago/Turabian StyleGhassemi Nejad, Jalil, Bae-Hun Lee, Ji-Yung Kim, Kyung-Il Sung, and Hong-Gu Lee. 2021. "Daytime Grazing in Mountainous Areas Increases Unsaturated Fatty Acids and Decreases Cortisol in the Milk of Holstein Dairy Cows" Animals 11, no. 11: 3122. https://doi.org/10.3390/ani11113122