Table 1
Detection methods for the serum parameters
| Parameter | Methoda |
|---|---|
| Mg, Ca, Pi | photometric determination |
| Na, K | ion-sensitive electrode |
| Fe | identification with ferrozine (without deproteinisation) |
| BHB | UV method |
| Bilirubin | according to Jendrassik and Grof (10) |
| NEFA, urea | kinetic UV assay |
| Creatinine | Jaffe reaction |
| AST | optimised standard method of DGKC |
| AP, CK | NAC-activated, optimised standard method of DGKC |
| γ-GT | according to Szasz (29) |
| TP | biuret method |
[i] DGKC – German Society of Clinical Chemistry and Laboratory Medicine
a performed at 37°C with Cobas C311 analyser, Roche Diagnostics GmbH, Germany
Table 2
Example cross table used for the calculation of odds ratios and McNemar’s test
 |
[i] RDC – recumbent dairy cows; CDC – control dairy cows; OR – odds ratio
≠ depending on clinical significance of deflection in recumbent dairy cows
Table 3
Descriptive statistics of study groups
| RDC group (n = 32) | CDC group (n = 32) | ||
|---|---|---|---|
| 1 (n/%) | 5 (15.6) | 5 (15.6) | |
| Number of lactations | 2 (n/%) | 7 (21.9) | 7 (21.9) |
| 3 (n/%) | 8 (25.0) | 8 (25.0) | |
| > 3 (n/%) | 12 (37.5) | 12 (37.5) | |
| mean ± SD | 144 ± 110 | 146 ± 111 | |
| DIM | min–max | 7–383 | 6–384 |
| Proportion of gravid cows | (n/%) | 14 (43.8) | 14 (43.8) |
| Day of gestationa | mean ± SD | 95 ± 72 | 89 ± 69 |
[i] RDC – recumbent dairy cows; CDC – control dairy cows; DIM – days in milk
a only gravid animals
Table 4
Serum concentrations of examined parameters of the study groups
| RDC group (n = 32) | CDC group (n = 32) | |||
|---|---|---|---|---|
| Parameter | Physiological rangea | Mean ± SD | Mean ± SD | P¥ |
| Mg (mmol/L) | 0.90–1.32 | 0.94 ± 0.16 | 1.03 ± 0.09 | 0.008 |
| Ca (mmol/L) | 2.00–2.54 | 2.32 ± 0.51 | 2.57 ± 0.16 | 0.012 |
| Pi (mmol/L) | 1.55–2.29 | 1.50 ± 0.61 | 1.91 ± 0.24 | < 0.001 |
| Na (mmol/L) | 135.00–157.00 | 147.31 ± 8.21 | 142.59 ± 5.71 | 0.008 |
| K (mmol/L) | 3.90–5.20 | 4.43 ± 0.75 | 5.10 ± 0.77 | < 0.001 |
| Fe (μmol/L) | 13.00–33.00 | 11.31 ± 8.15 | 25.06 ± 4.48 | < 0.001 |
| BHB (mmol/L) | < 0.62 | 0.47 ± 0.27 | 0.61 ± 0.24 | 0.003 |
| Bilirubin (μmol/L) | 3.30–5.30 | 4.24 ± 3.16 | 1.03 ± 0.55 | < 0.001 |
| NEFA (μmol/L) | < 400.00 | 509.72 ± 330.15 | 136.88 ± 76.36 | < 0.001 |
| Urea (mmol/L) | 2.00–6.80 | 5.06 ± 2.07 | 3.91 ± 0.96 | 0.025 |
| Creatinine (μmol/L) | 50.00–150.00 | 70.34 ± 19.67 | 71.05 ± 15.90 | 0.0625 |
| AP (U/L) | 40.00–300.00 | 54.19 ± 24.96 | 45.94 ± 13.98 | 0.062 |
| CK (U/L) | < 150.00 | 5011.28 ± 13386.53 | 666.44 ± 1645.44 | < 0.001 |
| AST (U/L) | < 80.00 | 231.07 ± 207.75 | 92.32 ± 14.96 | 0.020 |
| GGT (U/L) | < 50.00 | 36.43 ± 20.45 | 31.14 ± 12.36 | 0.0625 |
| TP (g/L) | 68.00–82.00 | 84.36 ± 8.01 | 80.72 ± 6.04 | 0.029 |
Table 5
Odds ratios for exceedance or lower deviation of serum parameter threshold values of the experimental group
| RDC group | ||||
|---|---|---|---|---|
| Parameter deviation | Physiological threshold valuea | OR | 95% CI | P¥ |
| Mg ↓ | < 0.90 mmol/L | 3.667 | 1.023–13.143 | 0.092 |
| Ca ↓ | < 2.00 mmol/L | 4.429 | 0.467–42.021 | 0.250 |
| Pi ↓ | < 1.55 mmol/L | x | ||
| Na ↓ | < 135.00 mmol/L | 0.484 | 0.042–5.621 | 1.000 |
| K ↓ | < 3.90 mmol/L | x | ||
| Fe ↓ | < 13.00 μmol/L | x | ||
| BHB ↑ | > 0.62 mmol/L | 0.407 | 0.121–1.369 | 0.227 |
| Bilirubin ↑ | > 5.30 μmol/L | x | ||
| NEFA ↑ | > 400.00 μmol/L | x | ||
| Urea ↑ | > 2.00 mmol/L | x | ||
| Creatinine ↑ | > 150.00 μmol/L | xx | ||
| AP ↓ | < 40.00 U/L | 0.866 | 0.302–2.481 | 1.000 |
| CK ↑ | > 150.00 U/L | 23.059 | 2.778–191.410 | < 0.001 |
| AST ↑ | > 80.00 U/L | 5.357 | 0.555–51.709 | 1.000 |
| GGT ↑ | > 50.00 U/L | 1.554 | 0.241–10.010 | 1.000 |
| TP ↑ | > 82.00 g/L | 2.341 | 0.843–6.353 | 0.210 |
[i] RDC – recumbent dairy cows; OR – odds ratio; CI – confidence interval; x – reference value was not exceeded but was attained in healthy cows; xx – reference value was exceeded in none of the study groups
a according to Fürll (9) and Van Winden et al. (31)
¥ McNemar’s test
Fig. 1
Box-and-whisker plots illustrating serum concentrations in diagnosis groups (1 – adductor muscle injury, 2 – fractures, 3 – other mechanical traumatic lesions of locomotor system, 4 – coliform mastitis, 5 – miscellaneous (ruminal tympany, cachexia, spinal abscess, tarsitis), 6 – healthy control animals). A – phosphorus, B – potassium, C – iron, D – β-hydroxybutyrate, E – total bilirubin, F – non-esterified fatty acids, and G – creatine kinase. Parameters returning means differing significantly between the RCD and CDC groups were chosen for these plots (Table 4). Descriptive differences between the diagnosis groups could not be proven to be statistically significant (P > 0.003). Group 6 (healthy control cows) was not included in the ANOVA for independent samples due to the dependent data structure of ANOVA (matched pairs of a recumbent dairy cow and a control dairy cow). Red horizontal lines – upper and lower limits of the reference ranges according to Fürll (9) and Van Winden et al. (31); horizontal lines within the boxes – medians; crosses within the boxes – means