Table 2 Potential risk factors for respiratory disease that were collected from the ten herds
From: Impact of diversity of Mycoplasma hyopneumoniae strains on lung lesions in slaughter pigs
Continuous variables | |
Times per year farmer is purchasing gilts | “X” times per year that the farmer purchased gilts |
Number of herds surrounding the herd in a perimeter of <5 km | calculated with Lambert coordinates and the Pythagoras theorem |
Number of sows present on the herd | Measure for the size of the herd |
Production system for the sows | 0: no week system, 1, 2, 3, 4-week system |
Coughing score given by the farmer | (0–10) fatteners |
Categorical variables | |
Purchase of gilts | 1 = yes, 0 = no |
Purchase of gilts always from the same supplier | 1 = yes, 0 = no |
Quarantine period for gilts | 1 = yes, 0 = no |
Herd located close to a highway (<5 km) | 1 = yes, 0 = no |
Herd located near a slaughter house (<5 km) | 1 = yes, 0 = no |
Distance herd to the public road (<100 or >100 m) | 1 (<100 m), 2 (>100 m) |
Sow breed | 0: Topigs, 1: LW + ELR + FLR, ELR + FLR, Danbred + hypor, Danbred, RA-SE, Hypor |
Dynamic or stable groups for pregnant sows | Stable (0) or dynamic (1) group sows |
AIAO farrowing unit | 1 = yes, 0 = no |
AIAO nursery unit | 1 = yes, 0 = no |
AIAO fattening unit | 1 = yes, 0 = no |
Stocking density nursery | 1 < 0.30 m2/pig; 2 > or = 0.30 m2/pig |
Cross fostering during first week of life piglets | 0 = no, 1 < 10%, 2 ≥10% |
Cross fostering after first week of life piglets | 0 = no, 1 < 10%, 2 ≥ 10% |
Stocking density fattening unit | 1 ≥ 0.70 m2/pig, 2 = 0.70–0.65 m2/pig, 3 < 0.65 m2/pig |
Cleaning and disinfection farrowing unit | 1 = yes, 0 = no |
Cleaning and disinfection nursery | 1 = yes, 0 = no |
Cleaning and disinfection fattening unit | 1 = yes, 0 = no, 2 = only cleaned not disinfected |
Stand empty period farrowing unit | 1 = yes, 2 = not always, 0 = no |
Stand empty period nursery unit | 1 = yes, 2 = not always, 0 = no |
Stand empty period fattening unit | 1 = yes, 2 = not always, 0 = no |
Gilts vaccinated against M. hyopneumoniae | 1 = yes, 0 = no |
Clinical signs of M. hyopneumoniae in grower-finishers | 1 = yes, 0 = no |