Feed is a possible carrier of pathogens and toxins. This is especially true with salmonella, mycotoxins (moulds), ionophores (cross-contamination with pre-mixes) and mycoplasma (cross-contamination during transportation). For this reason, (G)PS feed producers must follow strict programs for disease control in the production and transportation of feed.

Feed mills
A dedicated feed mill for the production of GPS feed is preferred. If PS feed is produced in the same feed mill, the standards for producing GPS feed should be applied.

The production of broiler, turkey and pig feeds is preferably done separately, to prevent cross-contamination with ionophores and other medications. This is also to prevent cross-contamination with dirty feed trucks to and from the farms.

Raw materials
The use of raw materials with an increased risk for salmonella contamination or mould growth must be avoided. Incoming raw materials must be monitored for the presence of salmonella as early as possible. This should be done preferably before being shipped to the feed mill.
During storage of raw materials, attention must be paid to humidity and temperature, to avoid growth of moulds.

Production
During production, the risk of (cross) contamination must be reduced by strictly monitoring the milling and mixing procedures. All premixes should be properly identified and tagged to prevent accidental mixing.

Treatments
The use of crumbled pellets, heat and the use of acids is recommended as a prevention against salmonella infection. In principle, the heat treatment should be seen as a method to reduce the possible presence of salmonella contamination, while the acid treatment should be seen as a method to prevent cross-contamination of salmonella after the production process. However, neither one of the methods should replace bio-secured raw materials and good milling procedures.

Although heat treatment helps to reduce the risk on contamination with Salmonella, it can influence the digestion of the birds and with it the quality of egg production systems

Binding toxins
Toxin binders are advisable, especially if raw materials used are mould sensitive or being harvested during moist conditions.

Feed transportation
Feed trucks can be transmitters of diseases especially for salmonella and mycoplasma. Dedicated feed trucks to be used for the GPS and PS operation decrease the risk. If this is not possible then feed deliveries should be done only on days directly after weekends and feed trucks should be cleaned and disinfected prior to delivery, especially for GPS farms