Skip to main content

Table 4 Carbon dioxide emissions of lactating Holstein dairy cows with different metabolic weights1

From: Characterization and mitigation option of greenhouse gas emissions from lactating Holstein dairy cows in East China

Items2 LMW MMW HMW SEM P-value
Metabolic weight, kg 126.3c 136.4b 147.8a 2.89 0.026
Milk production and composition
 Milk yield, kg/d 38.7 38.5 36.8 2.02 0.057
 Milk fat, % 3.66 3.73 3.81 0.26 0.062
 Milk protein, % 3.22 3.28 3.37 0.29 0.059
 Total milk solids, % 12.4 12.3 12.7 1.03 0.826
 FCM yield, kg/d 36.7 36.9 35.6 2.34 0.068
 ECM yield, kg/d 37.4 37.5 36.5 2.62 0.084
Carbon dioxide emissions
 Total CO2, g/d 18,996 19,269 19,339 20.83 0.475
 Total CO2/MW, g/kg 150.6 141.3 131.1 4.03 0.063
 Total CO2/ECM, g/kg 517.6 530.6 546.6 9.13 0.078
  1. 1LMW low metabolic weight (< 131.7, n = 36), MMW medium metabolic weight (131.7–141.2, n = 42), HMW high metabolic weight (> 141.2, n = 33), n number of observations in the data set
  2. 2FCM Fat-corrected milk (kg/d) = 0.4 × milk yield (kg/d) + 15 × fat yield (kg/d). ECM Energy-corrected milk (kg/d) = milk yield (kg/d) × [(38.3 × fat (%) × 10 + 24.2 × protein (%) × 10 + 16.54 × lactose (%) × 10 + 20.7) ÷ 3140. Total CO2, total CO2 production (g/d) = \( {\mathrm{CH}}_{4\left({\mathrm{CO}}_2-\mathrm{eq}\right)} \) (g/d) + CO2 production (g/d). MW metabolic weight (kg)
  3. a-c Means in the same row with different superscripts are significantly different (P < 0.05)