# Nano-coating with silicon dioxide to reduce the occurrence of bacterial contamination in a pig abattoir drinking system

## TL;DR

This study tested silicon dioxide nano-coating on pig abattoir drinking systems to reduce bacterial contamination but found no significant effect.

## Contribution

The study evaluates the effectiveness of nano-coating in reducing bacterial contamination in pig abattoir drinking systems for the first time.

## Key findings

- Nano-coating did not significantly reduce bacterial loads or presence compared to uncoated equipment.
- Combined methods like nano-coating and sanitary treatment may be needed for effective bacterial reduction.
- Modifications to the coating itself could improve its effectiveness in abattoir settings.

## Abstract

A recently discovered source for infection of slaughter pigs, and thus entry for bacteria into the food chain, is the installed drinking equipment in lairage pens of pig abattoirs. To mitigate this, nano-coating of stainless steel, currently used in human medicine fields as well as in other parts of the food chain, appears as promising technology. In this study, silicon dioxide nano-coating was applied to six drinkers and installed for one and three months in a lairage of a pig abattoir, while results were compared with those of drinkers that had not been nano-coated. Laboratory examination of eight sample types related to the drinkers was conducted for total aerobic plate count, Enterobacteriaceae count, Pseudomonas spp. count, Salmonella presence, pathogenic Yersinia enterocolitica presence, Listeria monocytogenes presence and methicillin-resistant Staphylococcus aureus presence. The nipple drinker, which the pigs take into their mouth for drinking, was then examined using scanning electron microscopy and elemental analysis. The nano-coating did not produce statistically significant reductions in the loads or presence of these bacteria compared to the same but uncoated drinking equipment used under the same conditions. Further studies should focus on the implementation of combined methods, such as nano-coating and sanitary treatment, as well as modifications to the coating itself, to produce meaningful reductions of the bacterial loads on/in abattoir lairage drinking equipment.