Salmonella in chicken : Current and developing strategies to reduce contamination at farm level

Salmonella sp. is a human pathogen that frequently infects poultry flocks. Consuming raw or undercooked contaminated poultry products can induce acute gastro-enteritis in human. Faced with the public health concern associated with salmonellosis, the European Union (EU) has established a European regulation forcing Member States (MS) to implement control programs aimed at reducing Salmonella prevalence in poultry production, especially at the primary production level. The purpose of the present review article is to summarise the current research and to suggest future developments in the area of Salmonella control in poultry, which may be of value to the industry in the coming years. The review will focus especially on preventive strategies that have been developed and that aim at reducing the incidence of Salmonella colonization in broiler chickens at farm level. Besides the usual preventive hygienic measures, different strategies have been investigated, like feed and drinking water acidification by organic acids and immune strategies based on passive and active immunity. Modulating the diet in terms of ingredient and nutrient composition with the intent of reducing the bird’s susceptibility to Salmonella has also been examined. Because in-ovo feeding has been shown to accelerate small intestinal development and to enhance the epithelial cell function, it could also be an efficient tool to control enteric pathogens. Microflora-modulating feed additives, like antibiotics, prebiotics, probiotics, and synbiotics, represent another field of investigation, whose success depends on the additive used. Finally, recent control methods, such as chlorate products and bacteriophages, have also been studied.