Table 4 The summary of the meta-analysis on the effects of probiotics on the blood biochemistry, immunity, and antioxidant indices of pre-weaning calves

Biochemical indexes

 ALP, U/L

8

0.554

−0.231, 1.339

0.166

36.490

 < 0.001

80.8

134.004

4.368

−3.901, 12.637

0.301

0.037

0.266

 ALB, g/L

9

0.751

−0.124, 1.627

0.093

50.100

 < 0.001

84.0

29.402

0.473

−0.205, 1.151

0.172

0.001

0.251

 ALT, U/L

7

0.476

−0.597, 1.549

0.385

46.600

 < 0.001

87.1

13.556

0.237

−0.619, 1.093

0.587

0.235

0.548

 AST, U/L

8

−0.792

−1.243, −0.342

0.001

12.650

0.081

44.6

51.416

−4.188

−6.741, −1.635

0.001

0.069

0.035

 BHBA, mmol/L

7

0.419

0.011, 0.826

0.044

8.290

0.217

27.6

0.257

0.029

−0.003, 0.062

0.077

0.533

0.548

 BUN, mmol/L

14

0.162

−0.998, 1.321

0.785

172.060

 < 0.001

92.4

3.484

0.056

−0.245, 0.358

0.714

0.748

0.827

 Glucose, mmol/L

20

−0.274

−0.828, 0.280

0.333

123.790

 < 0.001

84.7

4.219

−0.055

−0.236, 0.125

0.548

0.081

0.074

 Total protein, g/L

20

0.260

−0.110, 0.630

0.169

63.780

 < 0.001

70.2

56.384

0.750

−0.506, 2.007

0.242

0.492

0.347

 Total cholesterol, mmol/L

12

−0.731

−1.834, 0.373

0.194

121.270

 < 0.001

90.9

2.224

−0.060

−0.387, 0.268

0.720

0.803

0.304

 Triglyceride, mmol/L

5

−0.760

−2.270, 0.749

0.323

40.950

 < 0.001

90.2

0.309

−0.018

−0.051, 0.016

0.298

0.534

1.000

 LDH, U/L

6

−1.359

−1.990, −0.728

 < 0.001

10.570

0.061

52.7

708.462

−78.796

−123.059, −34.533

 < 0.001

0.159

0.060

Immune indices

 IgA, g/L

24

0.806

0.468, 1.144

 < 0.001

72.700

 < 0.001

68.4

2.847

0.313

0.209, 0.418

 < 0.001

 < 0.001

 < 0.001

 IgG, g/L

26

0.371

0.165, 0.578

 < 0.001

34.970

0.089

28.5

17.123

0.698

0.300, 1.095

0.001

0.073

0.011

 IgM, g/L

25

0.823

0.486, 1.160

 < 0.001

76.600

 < 0.001

68.7

2.010

0.262

0.162, 0.363

 < 0.001

 < 0.001

 < 0.001

 IGF1, ng/mL

7

0.872

−0.637, 2.381

0.258

89.830

 < 0.001

93.3

59.386

4.338

−3.577, 12.253

0.283

0.001

0.035

 IFN-γ, pg/mL

4

1.214

−0.262, 2.690

0.107

24.330

 < 0.001

87.7

47.043

4.277

3.359, 5.195

 < 0.001

0.379

0.089

Antioxidant indices

 MDA, nmol/mL

5

−1.238

−2.338, −0.138

0.027

20.550

 < 0.001

80.5

4.796

−0.404

−0.786, −0.021

0.039

0.881

0.462

 GSH-Px, U/mL

5

−0.076

−1.169, 1.016

0.891

23.690

 < 0.001

83.1

145.008

−2.938

−15.692, 9.817

0.652

0.416

0.806

 SOD, U/mL

9

0.199

−0.531, 0.929

0.592

50.610

 < 0.001

84.2

124.680

1.825

−6.306, 9.956

0.660

0.574

0.466

 T-AOC, U/mL

8

0.596

0.112, 1.079

0.016

20.030

0.005

65.1

8.009

0.441

0.208, 0.675

 < 0.001

0.101

0.108