Table 3 Factors associated with the durations of latency and infectiousness in SIV infected piglets.
Latency (days) | Infectiousness (days) | ||||
|---|---|---|---|---|---|
Variables and categories | n | Mean (sd) | P value (F test) | Mean (sd) | P value (F test) |
Gender | 0.6 | 0.47 | |||
M | 56 | 2.3 (1.4) | 7.0 (2.5) | ||
F | 51 | 2.1 (1.2) | 7.3 (2.2) | ||
Farm | < 0.001 | < 0.001 | |||
#A | 34 | 2.2b (1.0) | 6.8a (2.6) | ||
#B | 31 | 1.4a (0.4) | 5.9a (1.5) | ||
#C | 42 | 2.7b (1.7) | 8.3b (2.1) | ||
Age at SIV infection time (days) | < 0.001 | 0.004 | |||
≤ 50 | 61 | 2.6a (1.5) | 7.8b (2.4) | ||
]50 – 80] | 24 | 2.0ab (1.0) | 6.4a (2.5) | ||
> 80 | 22 | 1.4b (0.4) | 6.2a (1.6) | ||
Mean HI titre (log2) of the piglet (7 days of age) | 0.44 | 0.19 | |||
Low (≤5.9) | 24 | 2.5 (1.8) | 7.8 (2.0) | ||
Moderate (]5.9-6.9]) | 34 | 2.0 (0.97) | 7.3 (2.0) | ||
High (>6.9) | 49 | 2.2 (1.3) | 6.7 (2.7) | ||
H1 av N1 HI titre (log2) of the piglet (7 days of age) | 0.005 | 0.07 | |||
Low (≤5.3) | 26 | 2.8a (1.6) | 8.0 (2.1) | ||
Moderate (]5.3-7.3]) | 24 | 2.4ab (1.6) | 7.2 (2.3) | ||
High (>7.3) | 57 | 1.8b (0.9) | 6.7 (2.4) | ||
H1 hu N2 HI titre (log2) of the piglet (7 days of age) | 0.23 | 0.99 | |||
Low (≤5.3) | 24 | 2.1 (1.7) | 7.2 (1.9) | ||
Moderate (5.3-7.3) | 27 | 1.9 (0.9) | 7.1 (2.8) | ||
High (≥7.3) | 56 | 2.4 (1.3) | 7.1 (2.4) | ||
Mean HI titre (log2) of the dam (7 days post-farrowing) | 0.20 | 0.005 | |||
Low (≤5.9) | 48 | 2.3 (1.4) | 7.8a (1.6) | ||
Moderate (]5.9-6.9]) | 25 | 2.4 (1.4) | 7.2ab (2.5) | ||
High (>6.9) | 34 | 1.9 (1.0) | 6.1b (2.3) | ||
H1 av N1 HI titre (log2) of the dam (7 days post-farrowing) | 0.07 | < 0.001 | |||
Low (≤5.3) | 43 | 2.5 (1.4) | 7.8a (2.1) | ||
Moderate (]5.3-7.3]) | 22 | 2.3 (1.7) | 7.9a (2.3) | ||
High (>7.3) | 42 | 1.8 (0.9) | 6.1b (2.3) | ||
H1 hu N2 HI titre (log2) of the dam (7 days post-farrowing) | 0.38 | 0.71 | |||
Low (≤5.3) | 36 | 2.1 (1.5) | 7.4 (1.8) | ||
Moderate (]5.3-7.3]) | 32 | 2.5 (1.3) | 7.1 (2.4) | ||
High (>7.3) | 39 | 2.1 (1.2) | 6.9 (2.7) | ||
Dam parity | 0.02 | < 0.001 | |||
0–1 | 23 | 1.8 (0.9) | 7.1a (1.8) | ||
2–3 | 55 | 2.5 (1.5) | 8.0a (2.3) | ||
≥4 | 29 | 1.8 (1.0) | 5.6b (2.2) | ||
Number of stillborn or mummified piglets | 0.23 | 0.62 | |||
0 or 1 | 55 | 2.0 (0.9) | 7.0 (2.2) | ||
2 or more | 52 | 2.3 (1.6) | 7.3 (2.5) | ||
Number of cross-fostered piglets in the litter | 0.001 | 0.28 | |||
None | 39 | 1.9a (0.9) | 6.9 (2.0) | ||
Between 1 and 4 | 44 | 2.0a (1.1) | 7.0 (2.4) | ||
More than 4 | 24 | 3.0b (1.8) | 7.8 (2.8) | ||
H1 hu N2 specific seroconversion | 0.69 | 0.799 | |||
yes | 29 | 2.1 (1.4) | 7.2 (2.4) | ||
no | 78 | 2.2 (1.3) | 7.1 (2.4) | ||