PMID- 34644164
OWN - NLM
STAT- MEDLINE
DCOM- 20230927
LR  - 20231105
IS  - 1098-5336 (Electronic)
IS  - 0099-2240 (Print)
IS  - 0099-2240 (Linking)
VI  - 88
IP  - 1
DP  - 2022 Jan 11
TI  - Evaluation of the Impact of Antimicrobial Use Protocols in Porcine Reproductive 
      and Respiratory Syndrome Virus-Infected Swine on Phenotypic Antimicrobial 
      Resistance Patterns.
PG  - e0097021
LID - 10.1128/AEM.00970-21 [doi]
LID - e00970-21
AB  - A longitudinal study was conducted to assess the impact of different 
      antimicrobial exposures of nursery-phase pigs on patterns of phenotypic 
      antimicrobial resistance (AMR) in fecal indicator organisms throughout the 
      growing phase. Based on practical approaches used to treat moderate to severe 
      porcine reproductive and respiratory syndrome virus (PRRSV)-associated secondary 
      bacterial infections, two antimicrobial protocols of differing intensities of 
      exposure [44.1 and 181.5 animal-treatment days per 1000 animal days at risk 
      (ATD)] were compared with a control group with minimal antimicrobial exposure 
      (2.1 ATD). Litter-matched pigs (n = 108) with no prior antimicrobial exposure 
      were assigned randomly to the treatment groups. Pen fecal samples were collected 
      nine times during the wean-to-finish period and cultured for Escherichia coli and 
      Enterococcus spp. Antimicrobial-susceptibility testing was conducted using NARMS 
      Gram-negative and Gram-positive antibiotic panels. Despite up to 65-fold 
      difference in ATD, few and modest differences were observed between groups and 
      over time. Resistance patterns at marketing overall remained similar to those 
      observed at weaning, prior to any antimicrobial exposures. Those differences 
      observed could not readily be reconciled with the patterns of antimicrobial 
      exposure. Resistance of E. coli to streptomycin was higher in the group exposed 
      to 44.1 ATD, but no aminoglycosides were used. In all instances where resistances 
      differed between time points, the higher resistance occurred early in the trial 
      prior to any antimicrobial exposures. These minimal impacts on AMR despite 
      substantially different antimicrobial exposures point to the lack of 
      understanding of the drivers of AMR at the population level and the likely 
      importance of factors other than antimicrobial exposure. IMPORTANCE Despite a 
      recognized need for more longitudinal studies to assess the effects of 
      antimicrobial use on resistance in food animals, they remain sparse in the 
      literature, and most longitudinal studies of pigs have been observational. The 
      current experimental study had the advantages of greater control of potential 
      confounding, precise measurement of antimicrobial exposures which differed 
      markedly between groups and tracking of pigs until market age. Overall, 
      resistance patterns were remarkably stable between the treatment groups over 
      time, and the differences observed could not be readily reconciled with the 
      antimicrobial exposures, indicating the likely importance of other determinants 
      of AMR at the population level.
FAU - Odland, Carissa A
AU  - Odland CA
AUID- ORCID: 0000-0003-0787-4985
AD  - Pipestone Veterinary Services, Pipestone, Minnesota, USA.
FAU - Edler, Roy
AU  - Edler R
AD  - Pipestone Applied Research, Pipestone, Minnesota, USA.
FAU - Noyes, Noelle R
AU  - Noyes NR
AD  - University of Minnesotagrid.17635.36, Saint Paul, Minnesota, USA.
FAU - Dee, Scott A
AU  - Dee SA
AD  - Pipestone Applied Research, Pipestone, Minnesota, USA.
FAU - Nerem, Joel
AU  - Nerem J
AD  - Pipestone Applied Research, Pipestone, Minnesota, USA.
FAU - Davies, Peter R
AU  - Davies PR
AD  - University of Minnesotagrid.17635.36, Saint Paul, Minnesota, USA.
LA  - eng
GR  - #18-180/National Pork Board (NPB)/
PT  - Journal Article
PT  - Randomized Controlled Trial, Veterinary
PT  - Research Support, Non-U.S. Gov't
DEP - 20211013
PL  - United States
TA  - Appl Environ Microbiol
JT  - Applied and environmental microbiology
JID - 7605801
RN  - 0 (Anti-Bacterial Agents)
RN  - 0 (Anti-Infective Agents)
SB  - IM
MH  - Animals
MH  - Anti-Bacterial Agents/pharmacology
MH  - *Anti-Infective Agents
MH  - Drug Resistance, Bacterial
MH  - Escherichia coli
MH  - Longitudinal Studies
MH  - *Porcine respiratory and reproductive syndrome virus
MH  - Swine
PMC - PMC8752131
OTO - NOTNLM
OT  - E. coli
OT  - Enterococcus
OT  - antimicrobial resistance
OT  - pig
OT  - porcine reproductive and respiratory syndrome virus (PRRSV)
EDAT- 2021/10/14 06:00
MHDA- 2022/01/22 06:00
PMCR- 2022/01/11
CRDT- 2021/10/13 17:15
PHST- 2021/10/14 06:00 [pubmed]
PHST- 2022/01/22 06:00 [medline]
PHST- 2021/10/13 17:15 [entrez]
PHST- 2022/01/11 00:00 [pmc-release]
AID - 00970-21 [pii]
AID - aem.00970-21 [pii]
AID - 10.1128/AEM.00970-21 [doi]
PST - ppublish
SO  - Appl Environ Microbiol. 2022 Jan 11;88(1):e0097021. doi: 10.1128/AEM.00970-21. 
      Epub 2021 Oct 13.