Table 3.
Total VFAs (mg/100 ml) and individual VFAs expressed as a percentage (%) of total VFAs in the different intestinal compartments of the equine digestive tract according to the dietary treatment received (HS vs. HF)
| Intestinal compartments | VFAs | HS | HF | p-value | ||
|---|---|---|---|---|---|---|
| Diet | Sex | Diet*Sex | ||||
| SI | Total VFAs | 182.82 (130.20–235.04) | 176.81 (142.89–238.49) | 0.99 | 0.52 | 0.90 |
| Succinic | 11.09 (3.00–14.29) | 3.86 (0–16.87) | 0.29 | 0.47 | 0.80 | |
| Lactic | 5.23 (3.60–7.83) | 5.62 (2.96–26.27) | 0.76 | 0.19 | 0.46 | |
| Formic | 0 (0–1.04) | 0 (0–2.59) | 0.92 | 0.05 | 0.92 | |
| Acetic | 55.37 (4.15) | 51.32 (5.44) | 0.63 | 0.54 | 0.65 | |
| Propionic | 0 (0–0) | 0 (0–0) | 0.74 | 0.26 | 0.74 | |
| Iso-butyric | 24.84 (11.05–32.57) | 16.41 (11.63–24.66) | 0.55 | 0.02*a | 0.50 | |
| Butyric | 0 (0–0) | 0 (0–0) | 1.00 | 1.00 | 1.00 | |
| Iso-valeric | 0 (0–0) | 0 (0–0.80) | 0.38 | 0.38 | 0.38 | |
| Valeric | 0 (0–0) | 0 (0–0.88) | 0.59 | 0.64 | 0.75 | |
| CAE | Total VFAs | 510.72 (261.05–771.56) | 389.17 (290.76–462.55) | 0.57 | 0.95 | 0.30 |
| Succinic | 0 (0–0) | 0 (0–0) | 0.84 | 0.36 | 0.84 | |
| Lactic | 5.90 (2.43–6.84) | 3.57 (2.79–6.65) | 0.55 | 0.74 | 0.66 | |
| Formic | 0.50 (0.22–0.91) | 0 (0–0.99) | 0.10 | 0.01*b | 0.97 | |
| Acetic | 20.19 (14.00) | 30.16 (1.07) | < 0.01* | 0.88 | 0.53 | |
| Propionic | 4.19 (3.69–5.31) | 9.05 (6.91–10.72) | < 0.01* | 0.32 | 0.79 | |
| Iso-butyric | 45.09 (43.05–52.16) | 51.84 (47.31–56.48) | < 0.01* | 0.11 | 0.90 | |
| Butyric | 2.01 (1.66–2.18) | 3.79 (2.85–4.23) | < 0.01* | 0.31 | 0.54 | |
| Iso-valeric | 0 (0–0) | 0 (0–0) | 0.38 | 0.38 | 0.38 | |
| Valeric | 19.26 (15.00–27.36) | 0 (0–0) | < 0.01* | 0.64 | 0.64 | |
| SF | Total VFAs | 838.11 (622.74–1054.03) | 436.14 (381.38–489.42) | < 0.01* | 0.87 | 0.09 |
| Succinic | 0 (0–1.21) | 0.50 (0.31–0.95) | 0.19 | 0.35 | 0.79 | |
| Lactic | 5.70 (0.10–6.66) | 6.73 (4.88–12.33) | 0.06 | 0.62 | 0.36 | |
| Formic | 0.32 (0.27–1.11) | 0.65 (0–1.48) | 0.74 | 0.58 | 0.47 | |
| Acetic | 17.71 (1.51) | 33.42 (1.73) | < 0.01* | 0.29 | 0.08 | |
| Propionic | 3.80 (2.55–4.44) | 8.67 (7.01–9.74) | < 0.01* | 0.40 | 0.63 | |
| Iso-butyric | 39.29 (37.77–42.78) | 43.90 (36.91–49.68) | 0.31 | 0.34 | 0.95 | |
| Butyric | 2.72 (2.54–3.26) | 6.19 (5.35–7.29) | < 0.01* | 0.52 | 0.29 | |
| Iso-valeric | 0 (0–0.14) | 0 (0–0) | 0.51 | 0.37 | 0.69 | |
| Valeric | 30.74 (26.19–36.94) | 0 (0–0) | < 0.01* | 0.06 | 0.06 | |
| PF | Total VFAs | 897.97 (804.56–1121.135) | 303.72 (235.53–342.82) | < 0.01* | 0.30 | 0.50 |
| Succinic | 0 (0–0.68) | 0.47 (0–1.42) | 0.50 | 0.52 | 0.17 | |
| Lactic | 1.94 (0.23–3.92) | 1.93 (0.90–2.44) | 0.92 | 0.96 | 0.21 | |
| Formic | 0 (0–0.65) | 0.23 (0–1.19) | 0.51 | 0.68 | 0.25 | |
| Acetic | 13.93 (1.58) | 36.61 (0.75) | < 0.01* | 0.27 | 0.49 | |
| Propionic | 2.48 (2.23–3.64) | 9.60 (8.08–10.82) | < 0.01* | 0.22 | 0.75 | |
| Iso-butyric | 36.44 (32.23–42.31) | 47.17 (43.81–48.63) | < 0.01* | 0.28 | 0.04*c | |
| Butyric | 2.04 (1.31–2.30) | 4.10 (2.54–5.45) | < 0.01* | 0.13 | 0.72 | |
| Iso-valeric | 0 (0–0.20) | 0 (0–0.47) | 0.88 | 0.94 | 0.99 | |
| Valeric | 43.34 (36.43–43.32) | 0 (0–0) | < 0.01* | 0.33 | 0.33 | |
| RDC | Total VFAs | 835.54 (672.89–1090.51) | 284.62 (202.24–340.58) | < 0.01* | 0.58 | 0.41 |
| Succinic | 0.10 (0–0.56) | 0 (0–0.60) | 0.46 | 0.10 | 0.88 | |
| Lactic | 0.25 (0–3.29) | 3.03 (1.40–3.80) | 0.07 | 0.58 | 0.60 | |
| Formic | 0 (0–0.19) | 0 (0–0.21) | 0.76 | 0.63 | 0.25 | |
| Acetic | 15.93 (1.86) | 36.31 (2.29) | < 0.01* | 0.16 | 0.72 | |
| Propionic | 3.40 (2.73–3.84) | 8.92 (6.84–9.46) | < 0.01* | 0.40 | 0.52 | |
| Iso-butyric | 39.10 (25.67–41.05) | 46.62 (41.49–56.17) | < 0.01* | 0.14 | < 0.01*d | |
| Butyric | 1.78 (1.44–4.16) | 3.20 (2.35–4.16) | < 0.01* | 0.56 | 0.98 | |
| Iso-valeric | 0.18 (0–0.59) | 0 (0–0) | 0.06 | 0.13 | 0.43 | |
| Valeric | 39.25 (36.39–52.21) | 0 (0–0) | < 0.01* | 0.33 | 0.33 | |
| RE | Total VFAs | 605.76 (585.70–916.29) | 195.39 (134.52–295.35) | < 0.01* | 0.21 | 0.83 |
| Succinic | 0 (0–1.02) | 0 (0–0) | 0.08 | 0.58 | 0.58 | |
| Lactic | 3.04 (0.34–5.89) | 3.32 (2.14–4.13) | 0.61 | 0.08 | 0.28 | |
| Formic | 0 (0–0.23) | 0 (0–1.06) | 0.70 | 0.08 | 0.70 | |
| Acetic | 13.13 (1.37) | 28.82 (1.69) | < 0.01* | 0.05 | 0.71 | |
| Propionic | 2.08 (1.93–3.72) | 6.61 (5.89–8.80) | < 0.01* | 0.49 | 0.31 | |
| Iso-butyric | 37.12 (30.67–52.77) | 62.16 (53.42–64.11) | < 0.01* | 0.29 | 0.03*e | |
| Butyric | 1.45 (0.79–2.11) | 2.00 (0.93–2.60) | 0.92 | 0.17 | 0.95 | |
| Iso-valeric | 0 (0–0) | 0 (0–0) | 0.26 | 0.26 | 0.26 | |
| Valeric | 44.59 (19.98–51.79) | 0 (0–0) | < 0.01* | 0.11 | 0.11 | |
Data not normally distributed are expressed as medians (25th–75th percentiles); data normally distributed are expressed as means (SEM)
HS high starch, HF high fibre, SI small intestine, CAE apex of the caecum, SF ventral diaphragmatic flexure of the colon, PF pelvic flexure, RDC right dorsal colon, RE rectum. *statistical significance p < 0.05
*amales 30.50 (19.19–38.45); females 15.68 (7.97–22.90)
*bfemales 0.71 (0.12–1.33); males 0 (0–0.45)
*cmales HF 47.99 (46.75–50.55)A; females HF 46.44 (40.00–47.66)A; females HS 40.78 (34.74–50.79)AB; males HS 32.90 (28.32–36.35)B. A,B p < 0.05
*dmales HF 52.79 (47.17–60.11)A; females HF 43.19 (38.83–55.10)A; females HS 40.92 (35.16–48.41)A; males HS 25.67 (18.70–31.67)B. A,B p < 0.05
*emales HF 63.42 (62.30–64.41)A; females HF 57.33 (50.34–60.02)A; females HS 37.68 (36.17–66.13)AB; males HS 30.67 (23.87–37.92)B. A,B p < 0.05