Salmonella continues to be one of the most important zoonotic infections. A reduction of Salmonella at the farm level helps to mininimise the contamination pressure at the slaughterhouse. Although this is not the entire answer when it comes to preventing |Salmonella infection in pork consumers it is expected that pork producers will do their part in reducing carcass contamination levels at slaughter. These UK researchers wanted to confirm the effectiveness of a complete sanitation program in reducing Salmonella in finishing pigs. Two pig finisher buildings in each of 10 Salmonella positive farms were sampled pre-sanitation and post-sanitation , post-restocking with the following batch of pigs, and shortly before these pigs were sent to slaughter. One building on each farm (intervention) was sanitized according to a rigorous protocol consisting of several steps followed by an approved disinfectant. Rodent specialists visited the farms before and after sanitation and rodent carcasses were collected for Salmonella testing.
The researchers found the following:
- intervention buildings were significantly less likely (p = 0.004) to be positive for Salmonella after the more intense sanitation.
- The pre-restocking pigs had the highest likelihood (p<0.001) of being Salmonella positive (often with multiple serovars
- The pigs housed in the “intervention” buildings were significantly less likely (p = 0.004) to be positive for Salmonella at slaughter age.
- All the rats tested were Salmonella negative while S. Typhimurium or its monophasic variants were isolated from 6 mouse carcasses in 3 farms where the same serovars were isolated from pigs.
Take Home Messages:
- Cleaning all fixtures of buildings, leaving the pens empty for 2-3 days and using an effective disinfectant are significant factors in removing Salmonella contamination.
- Even though the incoming pigs were positive for salmonella the sanitation intervention was effective in reducing level at slaughter.
- Rodents can contribute to Salmonella carryover between batches
Ref: Martelli F, Lambert M, Butt P, Cheney T Tatone FA, Callaby R, Rabie A, Gosling RJ, Fordon S, Crocker G, Davies RH, Smith RP. Evaluation of an enhanced cleaning and disinfection protocol in Salmonella contaminated pig holdings in the United Kingdom. PLoS One. 2017 Jun 8;12(6):e0178897. doi: 10.1371/journal.pone.0178897. eCollection 2017.