Table 4.
Gene copy number of ETEC fimbriae genes, total ETEC fimbriae, UspA and toxins genes of diarrhea observed and health piglets detected by qPCR and HRM-qPCR methods. Data are presented as means of the log10 number of gene copies/g wet feces ± SEM in positive samples A
| Target genes | Diarrhea B Observations (n = 14) | Potential Diarrhea B Observations (n = 8) | Healthy animals (n = 8) B | |||
|---|---|---|---|---|---|---|
| Individual qPCR | Multiplex HRM-qPCR | Individual qPCR | Multiplex HRM-qPCR | Individual qPCR | Multiplex HRM-qPCR | |
| K99 fimbriae (fan A)* | 5.85 ± 0.14 (14/14)D |
7.52 ± 0.13 (14/14) |
6.35 ± 0.04 (8/8) |
3.99 ± 0.28 (6/8) |
6.37 ± 0.05 (8/8) |
3.97 ± 0.10 (5/8) |
| F41 fimbriae Subunit A* | 6.67 ± 0.07 (14/14) |
7.87 ± 0.13 (14/14) |
4.46 + 0.07 (8/8) |
3.62 ± 0.16 (6/8) |
4.67 ± 0.14 (8/8) |
4.47 ± 0.43 (7/8) |
| F18 fimbriae (Fed A) | 8.51 ± 0.17 (14/14) |
8.39 ± 0.22 (14/14) |
5.03 ± 0.09 (8/8) |
5.07 ± 0.08 (8/8) |
4.89 ± 0.09 (8/8) |
5.04 ± 0.14 (8/8) |
| F6 fimbriae (Fas A)* | 6.60 ± 0.06 (14/14) |
7.81 ± 0.12 (14/14) |
4.43 ± 0.10 (8/8) |
3.90 ± 0.09 (8/8) |
4.28 ± 0.10 (5/8) |
4.25 ± 0.12 (7/8) |
| K88 fimbriae (fae G) | 7.15 ± 0.07 (14/14) |
7.51 ± 0.14 (14/14) |
5.74 + 0.07 (8/8) |
4.10 ± 0.23 (8/8) |
5.52 ± 0.05 (8/8) |
3.60 ± 0.18 (6/8) |
| ETEC C | N/A | 7.99 ± 0.17a
(14/14) |
N/A | 4.63 ± 0.06b
(8/8) |
N/A | 4.68 ± 0.13b
(8/8) |
| Universal stress protein A | 9.21 ± 0.17 (14/14) |
N/A | 8.92 ± 0.20 (8/8) |
N/A | 8.80 ± 0.19 (8/8) |
N/A |
| Heat-labile toxin | 4.24 ± 0.23a
(9/14) |
N/A | < 3b | N/A | < 3b | N/A |
| Heat-stable toxins a | 6.22 ± 0.21a
(14/14) |
N/A | 5.11 ± 0.71a
(8/8) |
N/A | 3.02 ± 0.01b
(8/8) |
N/A |
| Heat-stable toxins b | 7.80 ± 0.18a
(14/14) |
N/A | 5.03 ± 0.09b
(8/8) |
N/A | 4.89 ± 0.09b
(8/8) |
N/A |
Athe detection limit of individual qPCR was 104 copies / g wet feces; the detection limit of multiplex HRM-qPCR was 105 copies / g wet feces
BDiarrhea observation corresponds to fecal scores of 7 or higher for more than 3 days; potential diarrhea observation corresponds to fecal scores ranging from 5 to 6 at least once; healthy animals corresponds to fecal scores of less than 5;
CETEC was calculated by the CT values and standard curve of HRM-qPCR detection for the feces samples, including the amplification of K99, F41, F18, F6, and K88. ETEC was calculated as the sum the gene copy numbers of all five fimbriae genes as obtained from the CT value of fecal samples by multiplex HRM-qPCR
Dnumber of positive samples / number of total samples
N/A, not analysed
*means results detected by qPCR and HRM-qPCR are significantly different (P < 0.05)
Data in the same row (ETEC, Universal stress protein A, Heat-labile toxin, Heat-stable toxin a and Heat-stable toxin b) that do not share a common superscript are significantly different (P < 0.05)