Table 4. Steroid ratios for detection and for source identification of faecal matter applied on faecal samples (old livestock breed and humans).
| No. | Ratio | Heck cattle | Sheep | Goats | Horses | Donkey | Geese | Pigs | Humans |
|---|---|---|---|---|---|---|---|---|---|
| Ratios for mere detection of faecal matter | |||||||||
| I | (coprostanol + epicoprostanol) / (5α-cholestanol + coprostanol + epicoprostanol)† | 0.76 ✔ | 0.78 ✔ | 0.55 +/- | 0.84 ✔ | 0.78 ✔ | 0.46 +/- | 0.90 ✔ | 0.99 ✔ |
| II | (5β-stigmastanol + epi-5β-stigmastanol) / (5α-stigmastanol + 5β-stigmastanol + epi-5β-stigmastanol) ‡ | 0.83 ✔ | 0.71 ✔ | 0.78 ✔ | 0.90 ✔ | 0.81 ✔ | 0.57 +/- | 0.86 ✔ | 0.95 ✔ |
| III | coprostanol / (5α-cholestanol + coprostanol) § | 0.74 ✔ | 0.77 ✔ | 0.50 +/- | 0.67 +/- | 0.74 ✔ | 0.43 +/- | 0.90 ✔ | 0.99 ✔ |
| IV | coprostanone / (cholestanone + coprostanone) § | 0.59 +/- | 0.48 +/- | 0.44 +/- | 0.88 ✔ | 0.65 +/- | 0.70 ✔ | 0.30 +/- | 0.20 ✘ |
| Ratios for source identification of faecal matter | |||||||||
| V | coprostanol / (coprostanol + 5β-stigmastanol) x 100% ¶ | 9% ✔ (7–13%) | 14% ✔ (10–20%) | 6% ✔ (5–8%) | 7% ✔ (6–9%) | 12% ✔ (11–13%) | 16% ✔ (12–21%) | 33% ✘ (29–38%) | 69% ✘ (66–71) |
| VI | epi-5β-stigmastanol / 5β-stigmastanol + epicoprostanol / coprostanol | 0.22 ✔ (0.18–0.29) | 0.11 ✔ (0.07–0.16) | 0.45 ✔ (0.36–0.55) | 2.36 ✔ (2.08–2.71) | 0.30 ✔ (0.27–0.32) | 0.19 ✔ (0.12–0.30) | 0.08 ✔ (0.04–0.13) | 0.01 ✔ (0.01–0.01) |
All ratios were calculated from the means of n = 3 laboratory replicates, except for the pigs (ratios were calculated from the means of the faecal steroid contents of Turopolje and Mangaliza pigs, n = 2 real replicates with each n = 3 laboratory replicates); range in parentheses
References for used ratios:
† Bull et al., 1999;
‡ modified from Bull et al., 1999;
§ Grimalt et al., 1990;
¶ Leeming et al., 1997
Ratios for detection of faecal matter (No. I-IV):
✔ = faecal input confirmed > 0.7;
+/- = faecal input can neither be confirmed nor excluded 0.3–0.7;
✘ = faecal input should be excluded < 0.3
Ratios for source identification of faecal matter:
No. V: < 38% faeces of herbivores; > 73% human faeces
No. VI: > 1.2 horse faeces; < 0.8 no horse faeces;
✔ source identification was possible
✘ source identification was not possible.