Study of Kampung Chicken Resistance to Salmonella enteritidis

A new study from Indonesia reveals that the local Kampung chicken are resistant to Salmonella enteritidis infection, which makes their eggs more suitable for a local speciality made with raw eggs.

28 November 2014

3 minute read

By: Jackie Linden

Kampung chicken eggs play an important role as substance in 'jamu' preparation in Indonesia, which is a dish mostly provided and consumed without cooking, according to a paper in International Journal of Poultry Science.

N. Ulupi and colleagues at Bogor Agricultural University in Indonesia explain that Salmonella-free eggs become significant in producing the safe jamu preparation and such eggs might be produced by chickens which have high resistance to this bacteria.

One of best markers showing resistance of chicken against Salmonella is an active Toll-like Receptor 4 (TLR4) gene. TLR4 is a phagocytes cell surface receptor that plays a role to recognise lipopolysaccharide of Gram-negative bacteria including Salmonella enteritidis. It is transcribed by TLR4 gene and conserved in the activation of the non-specific immune system.

The aim of the Bogor research was to prove resistance of Kampung chicken when was challenged with S. enteritidis, using TLR4 gene as marker.

TLR4 gene was genotyped in 50 Kampung chickens with PCR-RFLP. Then all the Kampung chickens were challenged with S. enteritidis (ID₅₀:5×10⁵ colony-forming units (CFU) per mL). Their expression on resistance against S. enteritidis as well as biological and molecular assays were measured.

The genotyping result identified three genotypes of TLR4 gene: AA, AG and GG. None of the parameters – including expression of TLR4 gene, concentration of leucocytes, differentiation of leucocytes, macrophages activity and capacity – was significantly different in AG and GG genotypes.

No S. enteritidis were found in blood or eggs produced by AA, AG and GG chickens.

IgY specific to S. enteritidis was found in eggs yolk with a very high concentration (2.94 to 3.89mg per mL).

The study proved that Kampung chicken resistant to S. enteritidis infection, concluded Ulupi and colleagues.

Reference

Ulupi N., Muladno, C. Sumantri and I.W.T. Wibawan. 2014. Study of Kampung chicken resistance against Salmonella enteritidis using TLR4 gene as marker. International Journal of Poultry Science. 13(8): 467-472.