Salmonella pullorum (Polyvalent) Stained Antigen

Salmonellosis is a serious problem currently threatening the poultry industry worldwide, and its culprit, Salmonella, is a Gram-negative parthenogenetic anaerobic bacterium that contains two major species, Salmonella bongori and Salmonella enterica. Among them, Salmonella gallinarium and Salmonella pullorum (Fowl typhoid) are avian-specific strains and the most pathogenic serotypes in birds, which can lead to systemic infections in birds and ultimately cause severe economic losses to the poultry industry. Salmonella belongs to the family Enterobacteriaceae and is rich in flagella on the whole cell body and is biochemically characterized by the production of hydrogen sulfide and catalase, the lack of oxidative enzymes as well as lactose fermentation properties. Salmonella has multiple serotypes, which are identified on the basis of somatic cell antigens and H-flagellar antigens in the bacterial flagellum. Unlike most Salmonella members, Salmonella gallinarium (SG) and Salmonella pullorum (SP) are flagellate and non-motile.

Figure 1. Avian Salmonellosis and its bacteriological characters
(Source: El-Saadony MT, et al. 2022)

SP infects birds via the oral route and obtains intestinal epithelial or lymphoid histiocytes in Peyer's patches and caecal tonsils. Free bacteria migrate with infected phagocytes to the lymphoid tissue where they multiply. It then returns to the intestinal lymphoid tissue and is excreted in the feces. In the early stages of infection, SP enters the GI tract via TLR5, a process that does not induce a significant inflammatory response and systemic infection. Researchers suggest Salmonella Pathogenicity Island-2 (SPI-2) gene may contribute to persistent infection during initial survival within macrophages.

Antibiotics are commonly used to minimize the impact of fowl typhoid on poultry and economic losses, but antibiotic use in poultry is declining due to increasing antibiotic resistance. In order to avoid the residual effects of antibiotics on poultry meat and the current situation of antibiotic resistance, many alternatives have been used to overcome these problems in order to obtain safe, cheap and organic poultry meat. Several antibiotic alternatives have been successful in controlling avian Salmonellosis, such as probiotics, prebiotics, commensals, organic acids, chitosan, nanoparticles and vaccines. These measures provide strategies for the control and prevention of avian Salmonellosis in developing or developed countries and provide safe and reliable poultry meat for human consumption, filling gaps and deficiencies in meat as a source of protein.

S. pullorum (Polyvalent) Stained Antigen