Fig 1.
Outcomes were compared for pigs managed with standard AB medication (T1), modified AB medication (T2), or an antibiotic-free (ABF) regimen (T3). AB = antibiotic; ADG = average daily gain; FCR = feed conversion ratio; IPC = Individual Pig Care; PRRSV = porcine reproductive and respiratory syndrome virus.
Table 1.
Pre-weaning performance comparison in litters raised using a standard (T1), modified antibiotic medication (T2), or ABF production protocol (T3).
Table 2.
Average daily gain and feed conversion ratio (FCR) by production phase and treatment group.
Data are presented as the LSmean ± SEM. Removal weights were not added back into the pen weight for the ADG and FCR calculations.
Fig 2.
Individual Pig Care (IPC) scores for treatment groups T1, T2, and T3 during the four months from weaning to finish.
The three numerical values adjacent to each bar indicate, in descending order, the IPC scores for categories A (mild clinical disease), B (moderate clinical disease), and C (severe clinical disease). IPC scores spiked immediately after PRRSV challenge (C arrow) and declined when ABF restrictions were lifted and group medication was initiated (M arrow) for all groups, including the antibiotic-free group T3 as an animal-health intervention. The standard medication group T1 had the lowest cumulative IPC scores before PRRSV challenge and during the month following challenge, indicating that this group had the lowest level of clinical disease, followed successively by the T2 and T3 groups.
Table 3.
Final market results for litters raised using a standard (T1) or modified (T2) antibiotic medication or an antibiotic-free (T3) production protocol.
Fig 3.
Caregiver responses to the survey question ‘Are you satisfied with the efficacy of the care being given to the study animals?’.
Response are shown as mean values on a 10-point scale from 1 (full agreement) to 10 (no agreement). Responses were based on the observed health status of pigs in each treatment group at each week of the study. For the first 11 weeks of the study, satisfaction scores were most favorable for T1 and T2 pigs at each time point compared to scores for ABF (T3) pigs. Relatively favorable scores for the T1 and T2 groups reflected the absence of clinical disease due to infection control treatment on day 0 or subsequent therapeutic AB treatment, which was denied in T3 pigs. C = challenge with PRRSV; M = group medication of pigs in all three groups, including T3 pigs.