Table 2. Feed intake, milk production, milk gross composition and fertility indicators on dairy farms with organic production system (ORG) and short-term (ORG-SG) or long-term grassland management (ORG-LG) and dairy farms with conventional production system (CON) and short-term (CON-SG) or long-term grassland management (CON-LG).
| Item | Farming system | P-value | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| ORG-SG | ORG-LG | CON-SG | CON-LG | SEM | G 1 | P(G) 2 | ORG-SG vs. ORG-LG 3 | CON-SG vs. CON-LG 4 | ORG vs. CON 5 | |
| n | 14 | 14 | 14 | 14 | ||||||
| Feed intake | ||||||||||
| Forage, GJ NEL 6 /year and cow | 23.9 | 21.9 | 22.8 | 20.0 | 0.99 | 0.02 | 0.31 | 0.20 | 0.04 | 0.15 |
| Forage, GJ NEL/100 kg ECM 7 | 0.362 a b | 0.376 a | 0.295 b | 0.312 a b | 0.0204 | 0.47 | 0.02 | 0.67 | 0.54 | 0.004 |
| Concentrates, GJ NEL/year and cow | 9.70 b | 8.55 b | 13.43 a | 13.53 a | 0.903 | 0.57 | <0.001 | 0.38 | 0.94 | <0.001 |
| Concentrates, GJ NEL/100 kg ECM | 0.141 b | 0.149 b | 0.173 a b | 0.208 a | 0.0122 | 0.09 | 0.003 | 0.65 | 0.05 | 0.001 |
| Milk production and milk gross composition | ||||||||||
| Lactating cows, adjusted to 305 d lactation | 21.7 | 15.0 | 18.3 | 17.5 | ||||||
| Milk quota, tonnes | 137 | 87 | 119 | 122 | ||||||
| Milk delivery, tonnes | 129 | 72 | 125 | 107 | ||||||
| ECM yield, kg/year and cow | 6,814 a b | 5,855 b | 7,787 a | 6,573 a b | 331.2 | 0.003 | 0.05 | 0.05 | 0.02 | 0.02 |
| Milk yield, kg/year and cow | 6,621 a b | 5,647 b | 7,550 a | 6,448 a b | 305.7 | 0.002 | 0.03 | 0.03 | 0.02 | 0.009 |
| Fat, g/kg milk | 4.11 | 4.35 | 4.17 | 4.11 | 0.202 | 0.66 | 0.68 | 0.40 | 0.82 | 0.66 |
| Protein, g/kg milk | 3.49 a | 3.29 c | 3.43 a b | 3.33 b c | 0.033 | <0.001 | 0.33 | <0.001 | 0.04 | 0.80 |
| Lactose, g/kg milk | 4.71 | 4.64 | 4.69 | 4.70 | 0.032 | 0.22 | 0.12 | 0.03 | 0.60 | 0.42 |
| Fertility indicators | ||||||||||
| Age at first calving, month | 25.8 | 26.6 | 25.3 | 25.1 | 0.65 | 0.64 | 0.23 | 0.38 | 0.82 | 0.12 |
| Calving interval, month | 12.9 | 13.4 | 12.4 | 12.5 | 0.39 | 0.30 | 0.09 | 0.31 | 0.76 | 0.03 |
| Cows culled due to fertility problems, number/total number of cows | 0.073 | 0.068 | 0.103 | 0.160 | 0.0278 | 0.36 | 0.07 | 0.91 | 0.16 | 0.04 |
1 G = Effect of grassland management.
2 P(G) = Effect of production system within grassland management.
3 Contrast of ORG-SG vs. ORG-LG.
4 Contrast of CON-SG vs. CON-LG.
5 Contrast of ORG vs. CON.
6 Net energy lactation.
7 Energy corrected milk
a, b, c Means within a row with different letters differ (Tukey-Kramer test, P < 0.05).