TABLE 5.
Multiple regression equations with the parameters of the biphasic survival model as dependent variables and the biological and chemical characteristics of the manure as independent variables
| Dependent variable | Regression equationa | Model
|
|
|---|---|---|---|
| Significance | R2 | ||
| kmax1 | 0.53 (intercept, P < 0.001) − 0.02 × Sent (R2part = 0.33, P = 0.016) + 0.006 × NDF (R2part = 0.13, P = 0.073) − 0.11 × stx1 (R2part = 0.12, P = 0.104) − 0.003 × pH2 (R2part = 0.10, P = 0.073) | P = 0.006 | 0.69 |
| kmax2 | 0.23 (intercept, P = <0.001) − 0.02 × coliforms (R2part = 0.35, P = 0.010) − 0.003 × Sent (R2part = 0.20, P = 0.022) − 9.55 × 10−4 × ADF (R2part = 0.07, P = 0.139) | P = 0.003 | 0.61 |
| sl | 71.58 (intercept, P < 0.001) − 7.86 × coliforms (R2part = 0.70, P < 0.001) | P < 0.001 | 0.70 |
| ttd | 190.48-11.70 × coliforms (R2part = 0.51, P = 0.001) − 0.14 × pH (R2part = 0.09, P = 0.063) | P = 0.007 | 0.60 |
a
Sent, species richness of Enterobacteriaceae as determined by DGGE; NDF, neutral detergent fiber content (cellulose, hemicellulose, and lignin content as percentage of organic matter per unit dry weight); stx1, natural presence of the gene coding for Shiga toxin 1 as detected with Taqman PCR; coliforms, total number of coliform bacteria (log CFU/g dry weight); ADF, acid detergent fiber content (cellulose and lignin content as percentage of organic matter per unit dry weight).