Genetic control of resistance to salmonellosis and to Salmonella carrier-state in fowl: a review

Abstract

Salmonellosis is a frequent disease in poultry stocks, caused by several serotypes of the bacterial species Salmonella enterica and sometimes transmitted to humans through the consumption of contaminated meat or eggs. Symptom-free carriers of the bacteria contribute greatly to the propagation of the disease in poultry stocks. So far, several candidate genes and quantitative trait loci (QTL) for resistance to carrier state or to acute disease have been identified using artificial infection of S. enterica serovar Enteritidis or S. enterica serovar Typhimurium strains in diverse genetic backgrounds, with several different infection procedures and phenotypic assessment protocols. This diversity in experimental conditions has led to a complex sum of results, but allows a more complete description of the disease. Comparisons among studies show that genes controlling resistance to Salmonella differ according to the chicken line studied, the trait assessed and the chicken's age. The loci identified are located on 25 of the 38 chicken autosomal chromosomes. Some of these loci are clustered in several genomic regions, indicating the possibility of a common genetic control for different models. In particular, the genomic regions carrying the candidate genes TLR4 and SLC11A1, the Major Histocompatibility Complex (MHC) and the QTL SAL1 are interesting for more in-depth studies. This article reviews the main Salmonella infection models and chicken lines studied under a historical perspective and then the candidate genes and QTL identified so far.

Use of Integrated Studies to Elucidate Potential Benefits from Genetic Resistance to Salmonella Carrier State in Fowl

“…Indeed, differences in expression of gallinacins observed by Sadeyen et al, (2004) and Sadeyen et al (2006) were found to be associated, in young chicken, with increased susceptibility but, in adults, with resistance. Similar variations with age should also be the case of a large proportion of genes or genome regions found to be involved in resistance (for a review, see Calenge et al, 2010). This result also implies that increasing genetic resistance of hens should reduce resistance in chicks.…”

“…One main feature of studies of genetic resistance to Salmonella is the very large number of resistance-related traits that were considered (see Calenge et al, (2010) for a review). They differ in many factors.…”

“…At the opposite, only the study of Beaumont et al (2003b) suspected a role of the TLR4 gene. Other candidate genes involved in the immune response were investigated using either polymorphisms within the gene or genetic markers (for a review, see Calenge et al (2010).…”

Antibiotics effect on salmonella spp .isolated from young chicks in chicken fields

“…More than 2,500 serotypes have been described mostly under the species (3,4). Salmonellosis, especially the one that manifests as Pullorum disease, is one of the commonest diseases of local poultry, which causes severe economic loss to the industry.…”

Karasinekteki (Musca domestica) Antimikrobiyal Peptidler Salmonella pullorum ile Enfekte Tavuklarda Bağırsak Lactobacillus acidophilus ve Mukozal Epitel Hücrelerini Etkiler

“…More than 2.550 Salmonella serotypes have been reported, mostly belonging to S. enterica [2] . Pullorum disease caused by S. enterica serovar.…”