A Meta-analysis Describing the Effects of the Essential oils Blend Agolin Ruminant on Performance, Rumen Fermentation and Methane Emissions in Dairy Cows †
Abstract
:Simple Summary
Abstract
1. Introduction
2. Materials and Methods
2.1. Literature Search and Study Description
2.2. Data Extraction
2.3. Meta-analyses
2.4. Statistical Analyses
3. Results
3.1. Overall Effects of Agolin
3.2. Short- and Long-term Effects of Agolin
4. Discussion
4.1. Animal Performance
4.2. Rumen Fermentation
4.3. Methane Emissions
5. Conclusions
Data Availability
Supplementary Materials
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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ID | Country | Year | Parity | Design | Unit | n1 | Days 2 | Diet Ingredients 3 | F:C ratio 4 | Reference |
---|---|---|---|---|---|---|---|---|---|---|
1 | USA | 2009 | Multiparous | Crossover | Pen | 4 | 28 | AH, WS, FA, ST, C | 67/33 | [10] |
2 | UK | 2015 | All | Crossover | Cow | 8 | 35 | GS, CS, PB, C | 78/22 | [14] |
3 | Hungary | 2008 | All | Crossover | Cow | 76 | 28 | CS, AH, SBM, C | 55/45 | Unpublished |
4 | UK | 2016 | Multiparous | Randomized block | Cow | 75 | 174 | GS, CS, PB, C | 76/24 | [13] |
5 | Netherlands | 2017 | 2nd parity | Randomized block | Cow | 3 | 22 | CS, GS, SBM, C | 70/30 | [9] |
6 | Spain | 2015 | Primiparous | Randomized block | Cow | 24 | 56 | GH, CS, AH, ST, SBM, C | 60/40 | [12] |
7 | Spain | 2015 | Multiparous | Randomized block | Cow | 6 | 56 | GH, CS, AH, ST, SBM, C | 60/40 | [12] |
8 | Spain | 2016 | All | Randomized block | Cow | 20 | 56 | GH, CS, AH, ST, SBM, C | 80/20 | [15] |
9 | Switzerland | 2012 | All | Randomized block | Cow | 80 | 180 | GS, CS, GH, C | 67/33 | [11] |
10 | Germany | 2012 | All | Randomized block | Pen | 8 | 60 | CS, GS, AS, SBM, C | 52/48 | Unpublished |
11 | Hungary | 2010 | All | Randomized block | Cow | 65 | 92 | CS, AH, SBM, C | 55/45 | Unpublished |
12 | Netherlands | 2017 | All | Straight through | Cow | 8 | 70 | CS, GS, SBM, C | 70/30 | [16] |
13 | Belgium | 2011 | Multiparous | Straight through | Cow | 4 | 42 | GS, CS, SBM, C | 83/17 | [8] |
14 | France | 2011 | Multiparous | Straight through | Cow | 6 | 42 | CS, GH, SBM, C | 70/30 | Unpublished |
15 | France | 2014 | Multiparous | Straight through | Cow | 6 | 42 | GS, GH, SBM, C | 55/45 | Unpublished |
16 | UK | 2014 | All | Straight through | Pen | 5 | 30 | GS, WB, PB, C | 67/33 | Unpublished |
17 | UK | 2014 | All | Straight through | Pen | 6 | 53 | GS, WW, PB, C | 72/28 | Unpublished |
18 | UK | 2014 | All | Straight through | Pen | 6 | 57 | GS, CS, PB, C | 64/36 | Unpublished |
19 | UK | 2014 | Primiparous | Straight through | Pen | 6 | 244 | GS, WW, ST, SBM, C | 64/36 | Unpublished |
20 | UK | 2014 | Multiparous | Straight through | Pen | 6 | 244 | GS, WW, ST, SBM, C | 64/36 | Unpublished |
21 | Italy | 2017 | All | Straight through | Pen | 4 | 365 | CS, GS, C | 67/33 | Unpublished |
22 | Spain | 2016 | Multiparous | Straight through | Pen | 7 | 365 | CS, GS, GH, C | 70/30 | Unpublished |
23 | Spain | 2016 | Primiparous | Straight through | Pen | 7 | 365 | CS, GS, GH, C | 70/30 | Unpublished |
Parameter 1 | Studies | Minimum | Maximum | Mean | Median | SD |
---|---|---|---|---|---|---|
Treatment duration (d) | 22 | 22.0 | 427 | 143 | 80.5 | 125.0 |
Days in milk (d) | 14 | 20.0 | 296 | 171 | 183 | 60.16 |
DMI (kg/d) | 16 | 15.6 | 27.4 | 21.4 | 22.4 | 3.547 |
Milk yield (kg/d) | 23 | 18.2 | 49.2 | 31.0 | 30.1 | 6.559 |
Milk Fat (%) | 16 | 3.32 | 4.80 | 4.03 | 3.92 | 0.445 |
Milk protein (%) | 16 | 2.79 | 3.51 | 3.25 | 3.29 | 0.190 |
Milk lactose (%) | 8 | 4.43 | 5.27 | 4.75 | 4.76 | 0.206 |
Milk SCC (log/mL) | 3 | 3.91 | 4.92 | 4.46 | 4.63 | 0.429 |
FPCM yield (kg/d) | 20 | 21.3 | 47.1 | 32.9 | 32.1 | 5.957 |
FCE (kg/kg) | 16 | 1.17 | 1.97 | 1.52 | 1.48 | 0.207 |
Rumen pH | 3 | 6.46 | 6.78 | 6.62 | 6.62 | 0.147 |
Total VFA (mmol/L) | 8 | 50.8 | 165 | 103 | 101 | 29.56 |
Acetate (%) | 7 | 57.7 | 76.5 | 66.3 | 66.8 | 6.252 |
Propionate (%) | 7 | 14.9 | 26.0 | 19.3 | 18.4 | 3.630 |
Butyrate (%) | 7 | 8.74 | 14.1 | 10.9 | 10.0 | 1.931 |
Protozoa (log cells/mL) | 3 | 5.00 | 5.80 | 5.43 | 5.52 | 0.333 |
CH4 production (g/d) | 8 | 229 | 445 | 321 | 291 | 78.86 |
CH4 yield (g/kg DMI) | 8 | 9.79 | 46.2 | 19.7 | 17.0 | 10.75 |
CH4 intensity (g/kg FPCM) | 8 | 6.66 | 17.2 | 12.2 | 13.3 | 3.310 |
Parameter 1 | n | Response Ratio (R) | 95% CI | p-Value | Heterogeneity | |
---|---|---|---|---|---|---|
Min. Max. | I2 | Q | ||||
DMI (kg/d) | 16 | 1.003 | 0.985-1.020 | 0.737 | 86 | <0.001 |
Milk yield (kg/d) | 23 | 1.020 | 1.011-1.028 | <0.001 | 16 | 0.248 |
Milk Fat (g/d) | 16 | 1.004 | 0.979-1.029 | 0.739 | 85 | 0.000 |
Milk protein (g/kg) | 16 | 1.002 | 0.996-1.008 | 0.419 | 46 | 0.023 |
Milk lactose (g/kg) | 8 | 0.998 | 0.992-1.003 | 0.519 | 76 | <0.001 |
Milk SCC (log/mL) | 3 | 0.994 | 0.944-1.045 | 0.800 | 69 | 0.040 |
FPCM yield (kg/d) | 20 | 1.031 | 1.026-1.035 | <0.001 | 0 | 0.995 |
FCE (kg/kg) | 16 | 1.030 | 1.011-1.049 | 0.002 | 34 | 0.087 |
Rumen pH | 3 | 1.006 | 0.989-1.022 | 0.476 | 0 | 0.511 |
Total VFA (mmol/L) | 8 | 0.982 | 0.946-1.019 | 0.346 | 0 | 0.685 |
Acetate (%) | 7 | 1.002 | 0.991-1.011 | 0.756 | 91 | <0.001 |
Propionate (%) | 7 | 1.011 | 0.945-1.082 | 0.744 | 97 | <0.001 |
Butyrate (%) | 7 | 0.991 | 0.963-1.019 | 0.525 | 7 | 0.377 |
Protozoa (log cells/mL) | 3 | 0.977 | 0.924-1.032 | 0.405 | 39 | 0.193 |
CH4 production (g/d) | 8 | 0.954 | 0.921-0.987 | 0.007 | 23 | 0.241 |
CH4 yield (g/kg DMI) | 8 | 0.982 | 0.918-1.050 | 0.600 | 42 | 0.088 |
CH4 intensity (g/kg FPCM) | 8 | 0.925 | 0.864-0.989 | 0.023 | 19 | 0.278 |
Parameter 1 | n | Response Ratio(R) | 95% CI | p-value | Heterogeneity | |
---|---|---|---|---|---|---|
Min.–Max. | I2 | Q | ||||
DMI (kg/d) | 17 | 1.000 | 0.976–1.024 | 0.988 | 84 | <0.001 |
Milk yield (kg/d) | 19 | 1.026 | 1.006–1.046 | 0.008 | 76 | <0.001 |
Milk Fat (g/kg) | 10 | 1.000 | 0.978–1.022 | 0.999 | 76 | <0.001 |
Milk protein (g/kg) | 10 | 1.002 | 0.991–1.012 | 0.731 | 55 | 0.018 |
Milk SCC (log/mL) | 3 | 1.036 | 0.984–1.090 | 0.177 | 0 | 0.910 |
FPCM yield (kg/d) | 16 | 1.028 | 1.009–1.047 | 0.004 | 69 | <0.001 |
FCE (kg/kg) | 15 | 1.010 | 0.989–1.029 | 0.348 | 40 | 0.055 |
Rumen pH | 3 | 1.007 | 0.991–1.023 | 0.385 | 0 | 0.445 |
Total VFA (mmol/L) | 9 | 0.973 | 0.936–1.010 | 0.158 | 4 | 0.400 |
Acetate (%) | 7 | 1.005 | 0.998–1.011 | 0.116 | 22 | 0.260 |
Propionate (%) | 7 | 1.009 | 0.969–1.049 | 0.672 | 39 | 0.131 |
Butyrate (%) | 7 | 0.985 | 0.958–1.012 | 0.276 | 0 | 0.544 |
Protozoa (log cells/mL) | 3 | 0.969 | 0.896–1.046 | 0.423 | 78 | 0.011 |
CH4 production (g/d) | 8 | 0.978 | 0.957–0.998 | 0.037 | 0 | 0.675 |
CH4 yield (g/kg DMI) | 8 | 0.980 | 0.923–1.039 | 0.497 | 49 | 0.047 |
CH4 intensity (g/kg FPCM) | 7 | 0.974 | 0.944–1.003 | 0.087 | 0 | 0.984 |
Parameter | n | Response Ratio(R) | 95% CI | p-Value | Heterogeneity | |
---|---|---|---|---|---|---|
Min.–Max. | I2 | Q | ||||
DMI (kg/d) | 16 | 1.003 | 0.980–1.026 | 0.777 | 86 | <0.001 |
Milk yield (kg/d) | 19 | 1.036 | 1.016–1.056 | <0.001 | 73 | <0.001 |
Milk Fat (g/kg) | 9 | 1.013 | 0.971–1.057 | 0.541 | 77 | <0.001 |
Milk protein (g/kg) | 9 | 0.993 | 0.973–1.012 | 0.465 | 88 | <0.001 |
Milk SCC (log/mL) | 3 | 1.000 | 0.987–1.012 | 0.972 | 0 | 0.777 |
FPCM yield (kg/d) | 15 | 1.041 | 1.028–1.054 | <0.001 | 5 | 0.392 |
FCE (kg/kg) | 12 | 1.044 | 1.007–1.080 | 0.016 | 79 | <0.001 |
Rumen pH | 3 | 1.005 | 0.988–1.020 | 0.578 | 0 | 0.546 |
Total VFA (mmol/L) | 6 | 0.978 | 0.932–1.026 | 0.373 | 5 | 0.383 |
Acetate (%) | 4 | 1.002 | 0.986–1.017 | 0.844 | 0 | 0.494 |
Propionate (%) | 4 | 1.002 | 0.948–1.059 | 0.932 | 0 | 0.994 |
Butyrate (%) | 4 | 0.974 | 0.888–1.067 | 0.568 | 0 | 0.397 |
Protozoa (log cells/mL) | 3 | 0.992 | 0.941–1.045 | 0.770 | 86 | 0.001 |
CH4 production (g/d) | 7 | 0.912 | 0.868–0.958 | <0.001 | 0 | 0.724 |
CH4 yield (g/kg DMI) | 7 | 0.871 | 0.802–0.945 | 0.001 | 0 | 0.986 |
CH4 intensity (g/kg FPCM) | 5 | 0.901 | 0.807–1.000 | 0.050 | 0 | 0.748 |
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Belanche, A.; Newbold, C.J.; Morgavi, D.P.; Bach, A.; Zweifel, B.; Yáñez-Ruiz, D.R. A Meta-analysis Describing the Effects of the Essential oils Blend Agolin Ruminant on Performance, Rumen Fermentation and Methane Emissions in Dairy Cows. Animals 2020, 10, 620. https://doi.org/10.3390/ani10040620
Belanche A, Newbold CJ, Morgavi DP, Bach A, Zweifel B, Yáñez-Ruiz DR. A Meta-analysis Describing the Effects of the Essential oils Blend Agolin Ruminant on Performance, Rumen Fermentation and Methane Emissions in Dairy Cows. Animals. 2020; 10(4):620. https://doi.org/10.3390/ani10040620
Chicago/Turabian StyleBelanche, Alejandro, Charles J. Newbold, Diego P. Morgavi, Alex Bach, Beatrice Zweifel, and David R. Yáñez-Ruiz. 2020. "A Meta-analysis Describing the Effects of the Essential oils Blend Agolin Ruminant on Performance, Rumen Fermentation and Methane Emissions in Dairy Cows" Animals 10, no. 4: 620. https://doi.org/10.3390/ani10040620