The vertical transmission of salmonellas and formic acid treatment of chicken feed. A possible strategy for control.

The treatment of feed given to laying hens with 0.5% formic acid reduced significantly the isolation rate of salmonellas and was associated with a reduction in the incidence of infection in newly hatched chicks. These improvements were not sustained until slaughter, however, as growing birds acquired salmonellas, probably from feed which was not acid treated. The data indicate that formic acid treatment of chicken food could have important benefits for the public health.