Haematocrit
The median haematocrit ranged from 14 to 40% among all groups (Table 1). Cows with TRP and U2 had a significantly lower haematocrit (TRP 30%, U2 14%) and cows with U4 a significantly higher haematocrit (40%) than controls (33%). The percentage of cows with a haematocrit in the reference interval was 87% in controls, and was significantly lower in all other groups (Table 2, Fig. 1). Anaemia with haematocrits < 27 and < 20% occurred in 4 and 0% of controls, respectively. Significantly more cows with TRP and U2 had a haematocrit < 27% (TRP 17%, U2 79%) than controls, and there were significantly more cows with a haematocrit < 20% in the U2 group compared with all other groups (70% vs 0–7%). The LR+ for a haematocrit < 27% and ≤ 20% in cows with U2 was 21 and 70, respectively (Table 3). Haemoconcentration with a haematocrit > 37% occurred in 9% of controls and significantly more often in cows with U1 (35%), U3 (27%), U4 (63%) and U5 (50%). A haematocrit > 44% was seen in 33% of cows with U4 (33%) but not in controls (Table 2). The LR+ for a haematocrit > 44% in cows with U4 was 33 (Table 3).
Table 1
Laboratory variables in healthy control cows and cattle with traumatic reticuloperitonitis (TRP), abomasal ulcer type 1 (U1), type 2 (U2), type 3 (U3), type 4 (U4) and type 5 (U5) (medians, 25 and 75% percentiles in brackets)
Variable
|
Controls
|
TRP
|
U1
|
U2
|
U3
|
U4
|
U5
|
Haematocrit (%)
|
332,4,6
(30–35)
|
301,3,4,5,6
(27–33)
|
342,4,6
(30–39)
|
141,2,3,5,6,7
(11–23)
|
342,4,6
(31–38)
|
401,2,3,4,5
(33–48)
|
384,6
(28–41)
|
Leukocytes (/µl)
|
80002,6
(6500–9400)
|
94001,6
(7400–11850)
|
7800
(5900-10'200)
|
90006
(6200-11'600)
|
81506
(6375-10’375)
|
62501,2,4,5
(4475–9200)
|
6100
(5000–8150)
|
Total protein (g/l)
|
782,4,6,7
(72–84)
|
841,4,5,6,7
(78–90)
|
784,6,7
(72–87)
|
481,2,3,5,6,7
(41–60)
|
762,4,6,7
(70–82)
|
651,2,3,4,5
(54–74)
|
661,2,3,4,5
(60–71)
|
Fibrinogen (g/l)
|
5.02,3,4,5,6,
(4.0–6.0)
|
8.01,3,4,5,6,7
(6.0–10.0)
|
6.01,2,4
(4.0–8.0)
|
4.01,2,3,5,6,7
(3.0–6.0)
|
6.51,2,4
(6.0–9.0)
|
6.01,2,4
(4.8–8.0)
|
5.42,4
(4.8–6.5)
|
Urea (mmol/l)
|
4.33,4,5,6
(3.3–5.4)
|
4.03,4,5,6
(3.0–5.3)
|
6.61,2,4
(4.7–8.8)
|
10.11,2,3,5,6
(8.0–12.4)
|
5.71,2,4
(3.9–7.4)
|
7.31,2,4
(5.0–11.4)
|
6.1
(4.2–9.4)
|
Potassium (mmol/l)
|
4.22,3,4,5,6
(4.0–4.4)
|
3.61
(3.3–4.0)
|
3.51
(3.1–4.0)
|
3.41
(3.0–3.9)
|
3.41
(2.9–4.0)
|
3.61
(3.1–4.0)
|
3.6
(3.2–4.2)
|
Chloride (mmol/l)
|
1004,6
(97–103)
|
1006
(97–103)
|
1006
(93–106)
|
1031,5,6
(99–106)
|
984
(92–103)
|
961,2,3,4
(92–101)
|
101
(95–104)
|
Base excess
(mmol/l)
|
1.72
(-0.4–3.3)
|
3.11,4
(-0.3–5.7)
|
3.6
(-1.0–7.9)
|
0.32
(-3.1–4.2)
|
2.4
(-1.2–8.2)
|
2.1
(-2.0–6.9)
|
1.1
(-1.2–3.9)
|
Rumen chloride
(mmol/l)
|
132,3,4,5,6
(12–16)
|
201,5
(15–26)
|
251
(19–36)
|
221,5
(18–31)
|
291,2,4,6
(21–43)
|
221,5
(17–29)
|
28
(18–34)
|
1 Difference to Controls P < 0.05, Kruskal Wallis test |
2 Difference to TRP P < 0.05, Kruskal Wallis test |
3 Difference to U1 P < 0.05, Kruskal Wallis test |
4 Difference to U2 P < 0.05, Kruskal Wallis test |
5 Difference to U3 P < 0.05, Kruskal Wallis test |
6 Difference to U4 P < 0.05, Kruskal Wallis test |
7 Difference to U5 P < 0.05, Kruskal Wallis test |
Table 3.
Diagnostic sensitivity and specificity, positive and negative predictive values and positive likelihood ratio of laboratory variables in cows with traumatic reticuloperitonitis (TRP), abomasal ulcer type 1 (U1), type 2 (U2), type 3 (U3), type 4 (U4) and type 5 (U5) (in percent)
Variable
|
Reliability
indices
|
TRP
|
U1
|
U2
|
U3
|
U4
|
U5
|
Haematocrit
|
Diagn. sensitivity
|
17
|
7
|
79
|
5
|
7
|
14
|
< 27 %
|
Diagn. specificity
|
96
|
96
|
96
|
96
|
96
|
96
|
|
Pos. pred. value
|
92
|
50
|
94
|
30
|
46
|
22
|
|
Neg. pred. value
|
30
|
67
|
85
|
75
|
68
|
94
|
|
LR+
|
4
|
2
|
21
|
1
|
2
|
4
|
Haematocrit
|
Diagn. sensitivity
|
1
|
0
|
70
|
2
|
5
|
7
|
≤ 20 %
|
Diagn. specificity
|
100
|
100
|
100
|
100
|
100
|
100
|
|
Pos. pred. value
|
100
|
-
|
100
|
100
|
100
|
100
|
|
Neg. pred. value
|
27
|
66
|
81
|
76
|
69
|
93
|
|
LR+
|
11
|
01
|
701
|
21
|
51
|
71
|
Haematocrit
|
Diagn. sensitivity
|
7
|
35
|
6
|
27
|
63
|
50
|
> 37 %
|
Diagn. specificity
|
91
|
91
|
91
|
91
|
91
|
91
|
|
Pos. pred. value
|
70
|
67
|
36
|
50
|
77
|
30
|
|
Neg. pred. value
|
26
|
73
|
55
|
79
|
84
|
96
|
|
LR+
|
1
|
4
|
1
|
3
|
7
|
6
|
Haematocrit
|
Diagn. sensitivity
|
1
|
3
|
1
|
5
|
33
|
7
|
> 44 %
|
Diagn. specificity
|
100
|
100
|
100
|
100
|
100
|
100
|
|
Pos. pred. value
|
100
|
100
|
100
|
100
|
100
|
100
|
|
Neg. pred. value
|
27
|
67
|
56
|
76
|
76
|
93
|
|
LR+
|
11
|
31
|
11
|
51
|
331
|
71
|
Total leukocyte count
|
Diagn. sensitivity
|
4
|
13
|
12
|
12
|
35
|
14
|
< 5’000/µl
|
Diagn. specificity
|
96
|
96
|
96
|
96
|
96
|
96
|
|
Pos. pred. value
|
74
|
63
|
71
|
50
|
81
|
22
|
|
Neg. pred. value
|
27
|
68
|
58
|
77
|
76
|
94
|
|
LR+
|
1
|
3
|
3
|
3
|
9
|
4
|
Total leukocyte count
|
Diagn. sensitivity
|
0
|
2
|
0
|
0
|
5
|
0
|
< 2’500/µl
|
Diagn. specificity
|
99
|
99
|
99
|
99
|
99
|
99
|
|
Pos. pred. value
|
50
|
67
|
50
|
0
|
80
|
0
|
|
Neg. pred. value
|
27
|
66
|
56
|
75
|
69
|
93
|
|
LR+
|
0
|
4
|
1
|
0
|
8
|
0
|
Total leukocyte count
|
Diagn. sensitivity
|
42
|
26
|
34
|
25
|
19
|
14
|
> 10’000/µl
|
Diagn. specificity
|
82
|
82
|
82
|
82
|
82
|
82
|
|
Pos. pred. value
|
86
|
42
|
59
|
31
|
33
|
6
|
|
Neg. pred. value
|
34
|
68
|
61
|
77
|
68
|
93
|
|
LR+
|
2
|
1
|
2
|
1
|
1
|
1
|
Total leukocyte count
|
Diagn. sensitivity
|
9
|
5
|
8
|
8
|
8
|
7
|
> 15’000/µl
|
Diagn. specificity
|
98
|
98
|
98
|
98
|
98
|
98
|
|
Pos. pred. value
|
94
|
63
|
79
|
63
|
70
|
25
|
|
Neg. pred. value
|
28
|
67
|
58
|
76
|
69
|
93
|
|
LR+
|
6
|
3
|
5
|
5
|
5
|
4
|
Total protein
|
Diagn. sensitivity
|
1
|
2
|
74
|
3
|
29
|
21
|
< 60 g/l
|
Diagn. specificity
|
98
|
98
|
98
|
98
|
98
|
98
|
|
Pos. pred. value
|
63
|
40
|
97
|
40
|
89
|
50
|
|
Neg. pred. value
|
27
|
66
|
83
|
76
|
74
|
94
|
|
LR+
|
1
|
1
|
45
|
2
|
17
|
13
|
Total protein
|
Diagn. sensitivity
|
0
|
1
|
53
|
0
|
10
|
NA
|
< 50 g/l
|
Diagn. specificity
|
100
|
100
|
100
|
100
|
100
|
100
|
|
Pos. pred. value
|
100
|
100
|
100
|
NA
|
100
|
NA
|
|
Neg. pred. value
|
27
|
66
|
73
|
75
|
70
|
93
|
|
LR+
|
01
|
11
|
531
|
01
|
01
|
NA
|
Total protein
|
Diagn. sensitivity
|
45
|
28
|
6
|
17
|
5
|
0
|
> 85 g/l
|
Diagn. specificity
|
81
|
81
|
81
|
81
|
81
|
81
|
|
Pos. pred. value
|
86
|
43
|
19
|
22
|
10
|
0
|
|
Neg. pred. value
|
35
|
68
|
52
|
75
|
64
|
91
|
|
LR+
|
2
|
1
|
0.3
|
1
|
1
|
1
|
Total protein
|
Diagn. sensitivity
|
5
|
3
|
1
|
3
|
0
|
0
|
> 100 g/l
|
Diagn. specificity
|
99
|
99
|
99
|
99
|
99
|
99
|
|
Pos. pred. value
|
92
|
60
|
33
|
50
|
0
|
0
|
|
Neg. pred. value
|
27
|
66
|
56
|
76
|
67
|
93
|
|
LR+
|
4
|
3
|
1
|
3
|
0
|
0
|
Fibrinogen
|
Diagn. sensitivity
|
5
|
8
|
34
|
5
|
9
|
14
|
< 4 g/l
|
Diagn. specificity
|
93
|
93
|
93
|
93
|
93
|
93
|
|
Pos. pred. value
|
64
|
35
|
79
|
19
|
38
|
13
|
|
Neg. pred. value
|
26
|
66
|
64
|
75
|
68
|
93
|
|
LR+
|
1
|
1
|
5
|
1
|
1
|
2
|
Fibrinogen
|
Diagn. sensitivity
|
3
|
6
|
22
|
5
|
3
|
14
|
< 3 g/l
|
Diagn. specificity
|
96
|
96
|
96
|
96
|
96
|
96
|
|
Pos. pred. value
|
68
|
46
|
82
|
30
|
30
|
22
|
|
Neg. pred. value
|
27
|
67
|
61
|
75
|
68
|
94
|
|
LR+
|
1
|
2
|
6
|
1
|
1
|
4
|
Fibrinogen
|
Diagn. sensitivity
|
69
|
29
|
8
|
43
|
45
|
21
|
> 7 g/l
|
Diagn. specificity
|
87
|
87
|
87
|
87
|
87
|
87
|
|
Pos. pred. value
|
93
|
53
|
33
|
52
|
62
|
11
|
|
Neg. pred. value
|
51
|
71
|
55
|
82
|
77
|
93
|
|
LR+
|
5
|
2
|
1
|
3
|
3
|
2
|
Fibrinogen
|
Diagn. sensitivity
|
45
|
11
|
5
|
23
|
16
|
0
|
> 9 g/l
|
Diagn. specificity
|
98
|
98
|
98
|
98
|
98
|
98
|
|
Pos. pred. value
|
99
|
77
|
70
|
82
|
82
|
0
|
|
Neg. pred. value
|
39
|
68
|
57
|
80
|
71
|
93
|
|
LR+
|
27
|
7
|
3
|
14
|
10
|
0
|
Urea
|
Diagn. sensitivity
|
14
|
51
|
89
|
35
|
56
|
43
|
> 6.5 mmol/l
|
Diagn. specificity
|
94
|
94
|
94
|
94
|
94
|
94
|
|
Pos. pred. value
|
86
|
81
|
92
|
66
|
81
|
35
|
|
Neg. pred. value
|
28
|
79
|
91
|
81
|
82
|
96
|
|
LR+
|
2
|
8
|
15
|
6
|
9
|
7
|
Urea
|
Diagn. sensitivity
|
6
|
28
|
70
|
13
|
41
|
29
|
> 8.5 mmol/l
|
Diagn. specificity
|
99
|
99
|
99
|
99
|
99
|
99
|
|
Pos. pred. value
|
97
|
96
|
99
|
89
|
97
|
80
|
|
Neg. pred. value
|
28
|
73
|
81
|
78
|
78
|
95
|
|
LR+
|
11
|
50
|
128
|
24
|
74
|
52
|
Potassium
|
Diagn. sensitivity
|
72
|
68
|
81
|
75
|
72
|
71
|
< 4 mmol/l
|
Diagn. specificity
|
77
|
77
|
77
|
77
|
77
|
77
|
|
Pos. pred. value
|
90
|
60
|
73
|
52
|
60
|
19
|
|
Neg. pred. value
|
50
|
82
|
84
|
90
|
85
|
97
|
|
LR+
|
3
|
3
|
4
|
3
|
3
|
3
|
Potassium
|
Diagn. sensitivity
|
13
|
21
|
20
|
25
|
20
|
14
|
< 3 mmol/l
|
Diagn. specificity
|
99
|
99
|
99
|
99
|
99
|
99
|
|
Pos. pred. value
|
98
|
95
|
97
|
94
|
94
|
67
|
|
Neg. pred. value
|
29
|
71
|
61
|
80
|
72
|
94
|
|
LR+
|
23
|
39
|
37
|
46
|
36
|
26
|
Chloride
|
Diagn. sensitivity
|
7
|
18
|
8
|
22
|
20
|
14
|
≤ 90 mmol/l
|
Diagn. specificity
|
98
|
98
|
98
|
98
|
98
|
98
|
|
Pos. pred. value
|
90
|
81
|
73
|
76
|
81
|
33
|
|
Neg. pred. value
|
28
|
70
|
58
|
79
|
72
|
94
|
|
LR+
|
3
|
8
|
4
|
10
|
9
|
7
|
Chloride
|
Diagn. sensitivity
|
2
|
9
|
1
|
3
|
5
|
7
|
≤ 80 mmol/l
|
Diagn. specificity
|
99
|
99
|
99
|
99
|
99
|
99
|
|
Pos. pred. value
|
80
|
80
|
50
|
50
|
67
|
33
|
|
Neg. pred. value
|
27
|
68
|
56
|
76
|
69
|
93
|
|
LR+
|
1
|
8
|
1
|
3
|
4
|
7
|
Base excess
|
Diagn. sensitivity
|
6
|
11
|
20
|
5
|
17
|
14
|
< -4 mmol/l
|
Diagn. specificity
|
95
|
95
|
95
|
95
|
95
|
95
|
|
Pos. pred. value
|
74
|
53
|
72
|
25
|
57
|
18
|
|
Neg. pred. value
|
29
|
70
|
66
|
77
|
75
|
94
|
|
LR+
|
1
|
2
|
4
|
1
|
4
|
3
|
Base excess
|
Diagn. sensitivity
|
0
|
3
|
11
|
0
|
6
|
7
|
< -8 mmol/l
|
Diagn. specificity
|
99
|
99
|
99
|
99
|
99
|
99
|
|
Pos. pred. value
|
67
|
75
|
93
|
0
|
80
|
50
|
|
Neg. pred. value
|
29
|
69
|
65
|
77
|
74
|
94
|
|
LR+
|
1
|
7
|
21
|
0
|
11
|
14
|
Base excess
|
Diagn. sensitivity
|
39
|
42
|
26
|
36
|
35
|
21
|
> +4 mmol/l
|
Diagn. specificity
|
88
|
88
|
88
|
88
|
88
|
88
|
|
Pos. pred. value
|
89
|
62
|
57
|
47
|
52
|
12
|
|
Neg. pred. value
|
37
|
77
|
66
|
82
|
78
|
94
|
|
LR+
|
3
|
3
|
2
|
3
|
3
|
2
|
Base excess
|
Diagn. sensitivity
|
19
|
28
|
14
|
27
|
25
|
14
|
> +7 mmol/l
|
Diagn. specificity
|
99
|
99
|
99
|
99
|
99
|
99
|
|
Pos. pred. value
|
99
|
96
|
94
|
94
|
95
|
67
|
|
Neg. pred. value
|
33
|
75
|
65
|
82
|
78
|
94
|
|
LR+
|
35
|
54
|
26
|
51
|
48
|
27
|
Rumen chloride
|
Diagn. sensitivity
|
13
|
36
|
25
|
44
|
22
|
40
|
> 30 mmol/l
|
Diagn. specificity
|
98
|
98
|
98
|
98
|
98
|
98
|
|
Pos. pred. value
|
95
|
91
|
90
|
89
|
83
|
57
|
|
Neg. pred. value
|
32
|
78
|
69
|
86
|
77
|
97
|
|
LR+
|
8
|
22
|
15
|
27
|
14
|
24
|
Rumen chloride
|
Diagn. sensitivity
|
6
|
19
|
10
|
26
|
9
|
10
|
> 40 mmol/l
|
Diagn. specificity
|
99
|
99
|
99
|
99
|
99
|
99
|
|
Pos. pred. value
|
96
|
94
|
92
|
93
|
86
|
50
|
|
Neg. pred. value
|
31
|
74
|
65
|
82
|
75
|
95
|
|
LR+
|
11
|
34
|
19
|
47
|
16
|
18
|
1 Calculation of the LR+ required the reduction of the diagnostic specificity from 100% to 99%
NA, not applicable
Values between 80 and 89% are in green
Values between 90 and 100% are in red
Values ≥10 are in blue
Total leukocyte count
The median total leukocyte count ranged from 6,100 to 9,400 cells/µl among all groups (Table 1). The total leukocyte count was significantly higher (9,400 cells/µl) in cows with TRP and significantly lower (6,250 cells/µl) in cows with U4 compared with controls (8,000/µl). The total leukocyte count was within in the reference interval in 78% (Table 2, Fig. 2), and leukopenia with < 5,000 and < 2,500 leukocytes/µl was seen in 4 and 1% of controls, respectively (Table 2). Leukopenia was significantly more common in cows with U4 (35%) than in controls (5%), cows with TRP (4%), U1 (13%), U2 (12%) and U3 (12%). The LR+ for leukopenia was low (0–9; Table 3).
Total protein concentration
The median total protein concentration ranged from 48 to 84 g/l (Table 1) and was significantly higher in cows with TRP (84 g /l) and significantly lower in cows with U2 (48 g/l), U4 (65 g/l) and U5 (66 g/l) compared with controls (78 g/l). Seventy-nine percent of controls had a total protein concentration in the reference interval (Table 2, Fig. 3), 2% had hypoproteinaemia and 19% had hyperproteinaemia. Cows with U2 (75%), U4 (29%) and U5 (21%) had hypoproteinaemia with < 60 g/l significantly more often than controls (2%), and cows with U2 (53%) and U4 (10%) had total protein concentrations < 50 g/l significantly more often than controls (0%); concentrations < 50 g/l were also significantly more common in cows with U2 compared with all other groups. The LR+ for hypoproteinaemia (< 60 g/l) was 45, 17 and 13 in cows with U2, U4 and U5, respectively (Table 3). Hyperproteinaemia > 85 g/l was significantly more common in cows with TRP (45%) and significantly less common in cows with U2 (6%) and U4 (5%) than in controls (19%). Total protein concentrations > 85 and > 100 g/l had positive predictive values of 86 and 92%, respectively, for TRP (Table 3)
Fibrinogen concentration
The median fibrinogen concentration ranged from 4 to 8 g/l (Table 1). The fibrinogen concentration was significantly higher in cows with TRP (8.0 g/l), U1 (6.0 g/l), U3 (6.5 g/l) and U4 (6.0 g/l) and significantly lower in cows with U2 (4.0 g/l) compared with controls (5.0 g/l). Eighty percent of control cows had a fibrinogen concentration in the reference interval (Table 2, Fig. 4), 7% had hypofibrinogenaemia and 13% had hyperfibrinogenaemia. Cows with U2 had fibrinogen concentrations < 4 (34%) and < 3 g/l (22%) significantly more often than controls. The LR+ for these test results ranged from 1 to 6 (Table 3). Cows with TRP (69%), U1 (29%), U3 (43%) and U4 (45%) had fibrinogen concentrations > 7 g/l significantly more often than controls (13%). Cows with TRP also had fibrinogen concentrations > 7 and > 9 g/l significantly more often than all other groups. The LR+ for a fibrinogen concentration > 9 g/l was 27 for TRP, 14 for U3 and 10 for U4 (Table 3).
Urea concentration
The median urea concentration ranged from 4.0 to 10.1 mmol/l (Table 1). Cows with U1 (6.6 mmol/l), U2 (10.1 mmol/l), U3 (5.7 mmol/l) and U4 (7.3 mmol/l) had significantly higher median urea concentrations than controls (4.3 mmol/l). Ninety-four percent of controls had a urea concentration in the reference interval (2.0–6.5 mmol/l), and 6% had azotaemia (Table 2, Fig. 5). Cows with U1 (51 and 28%), U2 (89 and 70%), U3 (35 and 13%), U4 (56 and 41%) and U5 (43 and 29%) had urea concentrations > 6.5 and > 8.5 mmol/l, respectively, significantly more often than controls (6 and 0.5%). Cows with U2 had azotaemia (89% >6.5 and 70% >8.5 mmol/l) significantly more often than cows of any other group. The LR+ for a urea concentration > 8.5 mmol/l was > 10 in all groups and reached 128 and 74 for U2 and U4, respectively (Table 3).
Potassium concentration
The median potassium concentration ranged from 3.4 to 4.2 mmol/l (Table 1). Except for cows with U5, all cows from the other disease groups had significantly lower potassium concentrations than controls. Seventy-six percent of controls had a potassium concentration in the reference interval (Table 2, Fig. 6) and 23 and 0.5% had hypokalaemia with concentrations of < 4 and < 3 mmol/l, respectively. In cows of all disease groups, concentrations < 4 (68 to 81% of cows) and < 3 mmol/l (13 to 25% of cows) were significantly more common than in controls. The LR+ for a potassium concentration < 3 mmol/l ranged from 23 to 46 in all disease groups (Table 3).
Chloride concentration
The median chloride concentration ranged from 96 to 103 mmol/l (Table 1). Eighty-nine percent of controls had normochloraemia (Table 2, Fig. 7) and 2 and 1% had hypochloraemia with concentrations ≤ 90 and ≤ 80 mmol/l, respectively. Cows with U1 (18%), U3 (22%) and U4 (20%) had hypochloraemia significantly more often than controls, and cows with U1 had concentrations ≤ 80 mmol/l significantly more often (9%) than controls. The LR+ for a chloride concentration ≤ 90 mmol/l was 10 in cows with U3 (Table 3). Hyperchloraemia was significantly more common in cows with U1 (30%) and U2 (28%) than in controls.
Base excess
The median base excess ranged from 0.3 to 3.6 mmol/l (Table 1). Eighty-two percent of controls had normal values of -4 to + 4 mmol/l (Table 2, Fig. 8), 6% had values lower and 12% had values greater than the reference interval. A base excess smaller than − 4 and − 8 mmol/l was recorded in 6 and 0.5% of controls, respectively (Table 2); values lower than − 4 mmol/l were significantly more common in cows with U2 (21%) and U4 (18%), and values lower than − 8 mmol/l were significantly more frequent in cows with U2 (11%) than in controls. The LR+ for a base excess lower than − 8 mmol/l was 21, 11 and 14 in cows with U2, U4 and U5, respectively (Table 3). A positive base excess greater than + 4 and + 7 mmol/l was significantly more frequent in cows with TRP, U1, U2, U3 and U4 (greater than + 4 mmol/l in 27 to 43%; greater than + 7 mmol/l in 14 to 28% including cows with U5) than in controls. The LR+ for a base excess greater than + 7 mmol/l ranged from 26 to 54 for all groups (Table 3).
Rumen chloride
The median rumen chloride concentration ranged from 13 to 29 mmol/l (Table 1). Except for cows with U5, all disease groups had significantly higher rumen chloride concentrations than controls. Ninety-eight percent of controls had rumen chloride concentrations in the reference interval (Table 2, Fig. 9) and 2% had concentrations exceeding 30 mmol/l. The percentage of cows from all disease groups with concentrations > 30 mmol/l (13 to 44%) was significantly greater compared with controls. Except for TRP, the LR+ for a rumen chloride concentration > 30 mmol/l was greater than 10 and ranged from 14 to 27 (Table 3).
Total protein concentration and haematocrit
The combined analysis of total protein concentration and haematocrit showed that 79% of cows with U2 had a decreased haematocrit, which was accompanied by hypoproteinaemia (30–59 g/l) in 73% and normoproteinaemia in 6% (Fig. 10A). In the other disease groups, a decreased haematocrit occurred in no more than 17% of the cows and was accompanied by normo-, hypo- or hyperproteinaemia. Most cows with a normal haematocrit had normoproteinaemia, some had hyperproteinaemia whereas hypoproteinaemia was rare (Fig. 10B). Most cows with increased haematocrit had normoproteinaemia and only rarely hypo- or hyperproteinaemia (Fig. 10C).
Total protein and fibrinogen concentrations
Seventy-five percent of cows with U2 had hypoproteinaemia, which was accompanied by normofibrinogenaemia in 42%, hypofibrinogenaemia in 32% and hyperfibrinogenaemia in 1% (Fig. 11A). Of the cows with normoproteinaemia (Fig. 11B), normofibrinogenaemia was most common in controls and cows with U1, U2, U3 and U5, and hyperfibrinogenaemia was most common in cows with TRP and U4. Most of the controls and cows with U1 with hyperproteinaemia had normofibrinogenaemia and most of the cows with TRP, U2, U3 and U4 with hyperproteinaemia had hyperfibrinogenaemia (Fig. 11C).