Table 4.
Univariable analysis of risk factors associated with SCM in lactating cow on herds in the Savannah region of Nigeria
| Variable | OR (crude) | SE | z | Pvalue | 95 % CI |
|---|---|---|---|---|---|
| Quarter |
0.918 |
0.048 |
−1.65 |
0.100 |
0.828; 1.016 |
| Month |
1.223 |
0.098 |
2.52 |
0.012 |
1.046; 1.430 |
| Herd size |
0.910 |
0.002 |
−0.31 |
0.758 |
0.996; 1.003 |
| Management system |
1.254 |
0.150 |
1.89 |
0.059 |
0.992; 1.585 |
| Breed |
1.241 |
0.094 |
2.85 |
0.004 |
1.069; 1.439 |
| Cow type |
1.333 |
0.159 |
2.40 |
0.016 |
1.054; 1.685 |
| Cow origin |
0.987 |
0.115 |
−0.11 |
0.914 |
0.785; 1.241 |
| Age (years) |
2.041 |
0.243 |
5.99 |
<0.001 |
1.616; 2.577 |
| Parity |
2.081 |
0.271 |
5.62 |
<0.001 |
1.611; 2.686 |
| BCS |
0.999 |
0.069 |
−0.01 |
0.991 |
0.873; 1.144 |
| Washing of teat |
0.755 |
0.100 |
−2.11 |
0.035 |
0.582; 0.980 |
| Pre-striping before milking |
0.359 |
0.155 |
−2.37 |
0.018 |
0.154; 0.836 |
| Washing hands before milking |
0.314 |
0.085 |
−4.28 |
<0.001 |
0.184; 0.533 |
| Heifer and cow |
0.245 |
0.121 |
−2.86 |
0.004 |
0.093; 0.643 |
| Replacement heifers |
0.926 |
0.130 |
−0.55 |
0.584 |
0.703; 1.219 |
| Feeding after milking | 2.787 | 1.203 | 2.37 | 0.018 | 1.196; 6.496 |
*Associations were evaluated by obtaining a crude OR estimate; variables with values of P ≤ 0.20 were considered significant and included in subsequent multivariable analysis; SCM = sub-clinical mastitis.