Table 4.
Item | System (S) | Full-Time Grazing (FT) | Part-Time Grazing (PT) | SEM | p-Values | |||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
FT | PT | GE1 | GE2 | GE3 | GE1 | GE2 | GE3 | S | GE | S × GE | ||
Milk yield, kg/day | 12.1 | 12.0 | 14.8 | 12.2 | 9.11 | 13.9 | 11.8 | 10.2 | 0.555 | 0.869 | <0.001 | 0.086 |
Milk gross composition, g/100 g | ||||||||||||
Fat | 4.08 | 3.86 | 3.93 b | 3.70 b | 4.62 a | 3.81 ab | 3.87 ab | 3.88 ab | 0.202 | 0.295 | 0.009 | 0.014 |
Protein | 3.65 | 3.45 | 3.65 | 3.57 | 3.75 | 3.45 | 3.40 | 3.49 | 0.094 | 0.049 | 0.267 | 0.859 |
Casein | 2.87 | 2.71 | 2.86 | 2.79 | 2.94 | 2.73 | 2.68 | 2.71 | 0.072 | 0.002 | 0.354 | 0.554 |
Lactose | 4.72 | 4.73 | 4.75 | 4.73 | 4.70 | 4.84 | 4.73 | 4.63 | 0.045 | 0.842 | 0.003 | 0.071 |
Urea | 18.3 | 20.9 | 17.8 b | 19.7 b | 17.4 b | 23.7 a | 18.8 b | 20.2 b | 0.850 | 0.018 | 0.007 | <0.001 |
Somatic cells, ×1000/mL | 139 | 129 | 107 b | 122 b | 206 a | 133 b | 148 b | 108 b | 13.50 | 0.770 | 0.423 | 0.025 |
pH | 6.68 | 6.64 | 6.69 a | 6.67 a | 6.68 a | 6.67 a | 6.65 a | 6.61 b | 0.013 | 0.038 | <0.001 | 0.004 |
Acidity, °SH | 6.57 | 6.73 | 7.16 | 6.34 | 6.21 | 7.10 | 6.52 | 6.56 | 0.162 | 0.369 | <0.001 | 0.339 |
Coagulation properties | ||||||||||||
Rennet coagulation time, min | 18.2 | 18.4 | 18.4 | 17.7 | 18.4 | 17.1 | 18.2 | 19.9 | 2.06 | 0.941 | 0.336 | 0.384 |
k20, min | 15.5 | 15.4 | 16.2 | 16.9 | 13.5 | 15.2 | 15.3 | 15.7 | 2.61 | 0.975 | 0.446 | 0.261 |
AR, mm | 23.8 | 23.0 | 23.7 ab | 21.7 b | 26.1 a | 21.7 ab | 23.0 ab | 24.1 ab | 1.35 | 0.586 | 0.003 | 0.060 |
AR: curd firmness after a strengthening time equal to the rennet coagulation time; k20: curd firming time to reach a value of 20 mm; SEM: standard error of the mean. a,b Different superscripts within the same row indicate differences between grazing systems and GEs (p < 0.05).