Ed Metzger from Southwest Ontario Veterinary Service, Does Prolonged Nursery Downtime Affect Bacterial Loads?


Sanitation measures such as cleaning, disinfection and downtime between production batches on pig farms are essential in preventing disease outbreaks. These measures may not eliminate all of the bacteria but a significant reduction in “infective pressure” can reduce the probability of disease. One of the questions that comes up from time to time is the potential benefit of longer downtime between batches. While we do know that downtime is an important factor for diseases such as PRRS and PED there a relatively few studies that have examined the effect of longer downtimes on bacteria in nursery units.


These Belgian researchers wanted to evaluated the potential benefit of a 10-day downtime period in pig nursery units on total aerobic flora, Enterococcus spp., Escherichia coli, fecal coliforms and methicillin resistant Staphylococcus aureus (MRSA). Three downtime periods of 10 days were monitored in each of 3 units. The microbiological load was measured before disinfection and at 1, 4, 7 and 10 days after disinfection.


The researchers were not able to identify any significant increase or decrease in E. coli, fecal coliforms, MRSA and Enterococcus spp associated with the prolonged downtime.. Total aerobic flora counts were the lowest on day 4 after disinfection (i.e. 4.07 log CFU/625 cm2) (P < 0.05), but the difference with other sampling moments was limited (i.e. 0.6 log CFU/625 cm2) and therefore negligible. Furthermore, this observation on day 4 was not confirmed for the other microbiological parameters. After disinfection, drinking nipples were still mostly contaminated with total aerobic flora (i.e. 5.32 log CFU/625 cm2) and Enterococcus spp. (i.e. 95 % of the samples were positive) (P < 0.01); the feeding troughs were the cleanest location (total aerobic flora: 3.53 log CFU/625 cm2 and Enterococcus spp.: 50 % positive samples) (P < 0.01).


Take Home Messages:

  1. There was no benefit with respect to bacterial load reduction after disinfection when downtime was increased to 10 days.
  2. It was interesting that the water nipples were the most heavily contaminated after cleaning and disinfection. Increased attention to the water supply may represent an opportunity for control of diseases such as postweaning colibacillosis.

Ref: Luyckx K, Millet S, Van Weyenberg S, Herman L, Heyndrickx M, Dewulf J, De Reu K. A 10-day vacancy period after cleaning and disinfection has no effect on the bacterial load in pig nursery units. BMC Vet Res. 2016 Oct 19;12(1):236.


1 Comment

  1. Don Entz

    Question. If u let a nursery sit idle for 10 days wouldn’t the best time to disinfect be day 8 or 9

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