Table 1.
Description of dichotomous BRD indicator outcome variables used in the LCA
| BRD indicator | Response category 1 | Response category 2 |
|---|---|---|
| Overall visual score: sum of all visual scores (range 0 to 21) | Score of 0 (n = 143) | Score ≥ 1 (n = 125) |
| Number of BRD treatments, 0 to 3 | Never treated or treated once for BRD (n = 228) | Treated more than once for BRD (n = 42) |
| Rectal temperature, °C at the time of pull | <40° rectal temp (n = 184) | ≥40° rectal temp (n = 86) |
| CALA, score 1 to 3 | Lung auscultation score < 2 (n = 101) | Lung auscultation score ≥ 2 (n = 169) |
| Lung consolidation, % | <10% total lung consolidated1 (n = 203) | ≥10% total lung consolidated (n = 22) |
| Pleural lesions, score 1 to 3 | Score ≤ 2 (n = 221) | Score 3 (n = 49) |
| BHV1 serostatus | Antibody positive at either induction or first BRD pull (pre-exposed; n = 110) | Seronegative at both induction and the first BRD pull (naïve; n=134) |
| BVDV serostatus | Antibody positive at either induction or first BRD pull (pre-exposed; n = 168) | Seronegative at both induction and the first BRD pull (naïve; n = 77) |
| BRSV serostatus | Antibody positive at either induction or the first BRD pull (pre-exposed; n = 240) | Seronegative at both induction and the first BRD pull (naïve; n = 6) |
| BPI3 serostatus | Antibody positive at either induction or first BRD pull (pre-exposed; n = 229) | Seronegative at both induction and the first BRD pull (naïve; n = 17) |
| BAdV3 serostatus | Antibody positive at either induction or first BRD pull (pre-exposed; n = 223) | Seronegative at both induction and the first BRD pull (naïve; n = 23) |
| BHV1 RT-qPCR swab result at the first BRD pull | Negative swab result at the first BRD pull (n = 245) | Positive swab result at the first BRD pull (n = 25) |
| BCoV RT-qPCR swab result at the first BRD pull | Negative swab result at the first BRD pull (n = 263) | Positive swab result at the first BRD pull (n = 7) |
| BRSV RT-qPCR swab result at first BRD pull | Negative swab result at the first BRD pull (n = 262) | Positive swab result at the first BRD pull (n = 8) |
| BPI3 RT-qPCR swab result at first BRD pull | Negative swab result at the first BRD pull (n = 269) | Positive swab result at the first BRD pull (n = 1) |
| BVDV RT-qPCR swab result at first BRD pull | Negative swab result at the first BRD pull (n = 262) | Positive swab result at the first BRD pull (n = 8) |