Staying clean to prevent cellulitis in broilers - Interpretive Summary

   

In the battle between biosecurity and disease, which safety measures have the best track records at preventing infections from spreading?

For a new study, a team of poultry scientists in Germany compared biosecurity measures on farms with the incidence of cellulitis, a bacterial skin infection that can make broiler carcasses unfit for consumption. Their research, published recently in The Journal of Applied Poultry Research, points to several ways to cut cellulitis cases—and overall disease occurrence.

“Using appropriate farm-specific clothing with changing of shoes and an adequate cleaning of the broiler houses after each grow out period helped to improve outcomes regarding total condemnation ratios as well as condemnation ratios due to cellulitis,” write study authors Schulze Bernd et al.

Cellulitis is common in many species and is usually caused by E. coli. The disease often causes inflamed, red and swollen skin. Overtime, a superficial case of cellulitis can lead to deep lesions. In Germany, cellulitis is reported as one of the main reasons broilers carcasses do not pass inspection—making cellulitis a burden on both animal welfare and the economy.

To help solve this problem, the researchers in the new study worked with 100 broiler farms in Germany to collect data on 199 broiler houses. The farmers answered a detailed questionnaire on their biosecurity practices. At the end of the grow out period, each farmer brought their broilers to the same processing plant. The processing plant then reported the total number of carcasses condemned for cellulitis and the overall total carcasses condemned.

The researchers were not surprised to learn that farms that cleaned out and disinfected broiler houses between flocks had a lower condemnation rate and cellulitis. They were, however, surprised to find that the disinfectant used had little effect. Interestingly, the total condemnation rate was lowest on farms where the farmer had recently changed disinfectant types due to a previous disease outbreak in a flock.

“From this, one could conclude that it is advantageous to review cleaning and disinfection procedures to react to existing disease processes in order to control them,” write the study authors.

Of the other security measures tracked, changing clothing and shoes between broiler houses made the most difference. On farms where farm staff wore protective clothing, the median cellulitis ratio dropped 10 percent compared with farms with no protective clothing. Supplying farm-specific clothing to farm visitors led to an additional 3 percent drop.

Factors such as manure management, proximity to a biogas plant and carcass handling did not affect the cellulitis ratios seen in this study, though the authors emphasize that additional measures, including minimizing the number of vehicles that enter a farm, can reduce cases of diseases like avian influenza.

   

The full paper, titled “Influences of biosecurity on the occurrence of cellulitis in broiler flocks,” can be found in The Journal of Applied Poultry Research and online here.

DOI: 10.1016/j.japr.2021.100230