Table 3.
Effect of C18 fatty acid source in the supplementary concentrate and measurement period on feed intake and nutrient digestibility of lactating dairy cows offered a pasture based diet (least square means ± SEM).
| Items | Treatment 1 | Measurement Period (MP) 2 | p-Value | |||||||
|---|---|---|---|---|---|---|---|---|---|---|
| SA | SO | LO | SEM | 1 | 2 | SEM | Treatment | MP | ||
| Intake (kg DM 3/d) | ||||||||||
| Pasture | 12.6 a | 11.5 b | 11.3 b | 0.32 | 11.9 | 11.6 | 0.26 | 0.02 | 0.53 | |
| Concentrate | 4.0 | 4.1 | 3.9 | 0.08 | 4.0 | 4.0 | 0.06 | 0.09 | 0.63 | |
| Total | 16.6 a | 15.6 a,b | 15.2 b | 0.31 | 15.9 | 15.6 | 0.26 | 0.01 | 0.44 | |
| GEI 3 (MJ/d) | 315 a | 292 b | 287 b | 5.8 | 298 | 298 | 4.7 | 0.004 | 0.90 | |
| Digestibility (%) | ||||||||||
| DM 3 | 66.9 b | 67.6 a,b | 69.1 a | 0.05 | 68.5 | 67.3 | 0.04 | 0.02 | 0.05 | |
| OM 3 | 70.1 b | 71.0 a,b | 72.4 a | 0.05 | 71.4 | 70.9 | 0.04 | 0.007 | 0.45 | |
| CP 3 | 64.6 a | 61.2 b | 62.3 b | 0.06 | 58.9 | 66.5 | 0.05 | 0.001 | <0.001 | |
| NDF 3 | 63.4 a | 64.7 a,b | 66.3 b | 0.09 | 63.7 b | 65.9 | 0.07 | 0.07 | 0.03 | |
| ADF 3 | 62.0 | 62.5 | 64.8 | 0.01 | 62.7 | 63.5 | 0.08 | 0.12 | 0.46 | |
1 SA = supplementary concentrate containing 16% FW stearic acid; SO = supplementary concentrate containing 16% FW soy oil; LO = supplementary concentrate containing 16% FW linseed oil; 2 MP = measurement period, MP 1 corresponds to 17 to 22 d post treatment introduction and MP 2 corresponds to 44 to 49 d after treatment introduction; 3 DM = dry matter; OM = organic matter; CP = crude protein; NDF = neutral detergent fiber; ADF = acid detergent fiber; ADL = acid detergent lignin; WSC = water soluble carbohydrates. a,b Means within rows differ significantly.