Table 2 Descriptive statistics of the 497 calves over the complete study period (average 154.5 days)

n

497

247

250

Average weight at weaning (kg)

83.4 ± 12.0 (40.5–126)

83.9 ± 12.6 (40.5–122)

82.8 ± 11.3 (52.5–126)

Average weight at the end of the study (kg)

233.7 ± 25.6 (126–310)

233.4 ± 26.2 (146–310)

233.9 ± 25.1 (126–302)

Daily gain, milk-feeding period (g/day)

630.7 ± 176.6 ((− 40)-1160)

641.7 ± 184.6 ((− 40)-1070)

619.6 ± 168.1 (150–1160)

Daily gain, complete study period (g/day)

1145.7 ± 136.9 (500–1520)

1151.9 ± 137.9 (670–1520)

1139.5 ± 135.9 (500–1460)

n (enrolled < 17 days of age)

261

139

122

Daily gain, (g/day)

1119.7 ± 131.0 (670–1460)

1109.3 ± 134.7 (670–1410)

1131.5 ± 126.2 (780–1460)

n (enrolled ≥17 days of age)

224

102

122

Daily gain, (g/day)

1176.0 ± 137.6 (500–1520) ^a

1209.9 ± 120.3 (880–1520)

1147.6 ± 145.0 (500–1460)

Clinical condition (2nd clin. exam) ^b

2.7 ± 1.9 (0–9)

2.7 ± 2 (0–8)

2.8 ± 1.8 (0–9)

BRD-diagnosis (2nd clin. exam) ^b

206 ^a

91

115

Antimicrobial treatments for

443

233

210

BRD

226

120

106

interdigital phlegmon

100

55

45

other inflammation

41

21

20

unknown fever

76

37

39

Oxytetracycline courses

304

157

147

Benzylpenicillin courses

139

76

63

Time to first medication (days)

20.7 ± 18.6 (0–93)

21.7 ± 19.2 (0–81)

19.6 ± 17.9 (0–93)

Premature death

12

6

6