Immunopotentiation of a developed Salmonella enterica serotype enteritidis vaccine by thymulin and zinc in meat chicken breeders

Development of recombinant subunit vaccine targeting InvH protein of Salmonella Typhimurium and evaluation of its immunoprotective efficacy against salmonellosis

Salmonella Typhimurium is the most prevalent non-host specific Salmonella serovars and a major concern for both human and animal health systems worldwide contributing to significant economic loss. Type 3 secretion system (T3SS) of Salmonella plays an important role in bacterial adherence and entry into the host epithelial cells. The product of invH gene of Salmonella is an important component of the needle complex of the type 3 secretion system. Hence, the present study was undertaken to clone and express the 15 kDa InvH surface protein of Salmonella Typhimurium in an E. coli host and to evaluate its immune potency in mice. The purified recombinant InvH (r-InvH) protein provoked a significant (p < 0.01) rise in IgG in the inoculated mice. The immunized mice were completely (100%) protected against the challenge dose of 107.5 LD50, while protection against challenge with the same dose of heterologous serovars was 90%. The bacterin-vaccinated group showed homologous protection of 60% against all three serovars. Findings in this study suggest the potential of the r-InvH protein of S. Typhimurium as an effective vaccine candidate against Salmonella infections.

Influence of Zinc Sulphate on the Probiotic Properties of Lactobacillus plantarum CCM 7102

The effects of zinc sulphate on selected properties of L. plantarum CCM 7102 were tested in vitro. The resistance of lactobacilli to higher concentrations of ZnSO4 (up to 5000 mg Zn2+.l−1) in growth media was strain-dependent. Further studies were carried out on the most resistant strain of L. plantarum CCM 7102. While the addition of low concentrations of zinc sulphate into the growth media (< 100 mg Zn2+.l−1) did not influence the properties of L. plantarum CCM 7102, the concentrations of 100—500 mg Zn2+.l−1 stimulated: the growth rate, production of lactic acid, adhesion to porcine enterocytes and the inhibition of pathogens E. coli O8:K88+ent+, S. enterica and S. Typhimurium. Conversely, however, high concentrations > 500 mg Zn2+.l−1 inhibited these properties. The addition of zinc (250 mg Zn2+.l−1) did not affect the resistance to antimicrobials, low pH, and the resistance to bile salt was affected only weakly. Zinc-resistant probiotic Lactobacillus strains are suitable for use in feedstuffs with a higher content of zinc designed for the prevention of post weaning diarrhoea in pigs.

Development of broiler chickens after treatment with thymulin 5cH: a zoo technical approach

Modulation of immune response due to thymulin 5cH has been previously observed. The aim of the present study is to evaluate the development of broiler chickens treated with thymulin 5cH by conventional zoo technical indices, phytohemaglutinin induced inflammation test and histomorphometric analysis of lymphoid organs (thymus, Fabricius bursa and spleen). Animals were divided in two groups: (a) test: birds with free access to thymulin 5cH diluted into the drink water and (b) control: birds with free access to water only, from the 1st to the 42nd day of life. All experimental procedures were done in blind. The results show that thymulin 5cH treated group had increased productivity index compared to control (391.45 versus 261.93) associated with higher viability in the 7th week (p = 0.013), and a possible shunt to B lymphocyte activity. The data suggest that thymulin 5cH could be a viable method to improve productivity in poultry production due to its immune modulation properties.

Effects of polyether ionophores on the protective immune responses of broiler chickens against Angara disease and Newcastle disease viruses

Immunization against Angara disease virus (ADV), a serotype 4 avian adenovirus, and Newcastle disease virus (NDV), an avian paramyxovirus serotype 1, is the mainstay of a broiler vaccination programme, while polyether ionophores usually form an essential component of a broiler medication programme in most parts of India and Pakistan. The role of polyether ionophores in the protective immune responses of broiler chickens vaccinated and challenged with ADV and NDV was investigated. A total of 1600 birds were divided into eight groups of 200 birds each. First four groups were vaccinated against NDV and ADV, while the remaining four served as unvaccinated controls. The first 3 groups of birds were administered salinomycin, monensin and cyclophosphamide (CYP), respectively. The last group served as an untreated control. The same treatment schedule was also followed for the next four unvaccinated groups. The post-vaccination and post-challenge serological responses to NDV and ADV, body and lymphoid organ weight gains, post-challenge survival rate and detection of NDV and ADV in the tissues of infected birds were evaluated. Birds administered salinomycin showed a significant stimulation of protective immune responses against both NDV and ADV as compared to the untreated and CYP-treated birds. Monensin also enhanced the protective immune responses against both viruses but the effect was not statistically significant. Thus, it is concluded that monensin and salinomycin augment the anti-NDV and anti-ADV immune responses in broiler chickens, which supports their use in poultry flocks.

Avian thymic hormone treatment of peripheral blood mononuclear cells from young chicks stimulates acute graft-versus-host reaction in chicken embryos

Avian thymic hormone (ATH) is a parvalbumin produced by epithelial cells in the thymic cortex of chickens and circulates in the blood on a 5-day cycle. It stimulates precocious development of cell-mediated immunity. The effect of partially purified extracts of thymus (TE) and purified ATH were tested for their effect on the acute graft-versus-host reaction (GVHR). Treatment of chicks for their first 3-days of life did not enhance the acute GVHR produced by their PBMC in 14-day-old embryos. PBMC from 3-day-old chicks were treated in vitro with TE, ATH, thymosin fraction 5 or thymosin alpha1 for 2 h and injected into 14-day-old embryos. Bone marrow cells and thymic lymphocytes were treated with TE. Only PBMC treated with TE or ATH produced an enhanced acute GVHR. Because ATH targets gammadelta T cells, the data implicate participation of donor gammadelta T cells in the acute GVHR.

Evaluation of 12 stabilizers in a developed attenuated Salmonella Enteritidis vaccine

The development of a stable live attenuated Salmonella Enteritidis (SE) vaccine, resisting heat stress during transportation and storage in unequipped tropical and subtropical zones of the world, is highly recommended. Twelve stabilizers were individually supplemented into a 9 ml volume of sterile distilled water resulting in concentrations of 1, 2, 3, 4 and 5%. A volume of 1 ml of attenuated live SE vaccine is added over the 9 ml of each concentration of the stabilizers. The differently stabilized SE vaccines were stressed at 55 degrees C for 48 h. The lowest percent reductions in SE cell viability by specified level of each stabilizer in ascending order were: 22.3% by 2% skim milk, 55.1% by 5% bovine serum albumin (BSA), 59.2% by 4% sorbitol, 74.4% by 3% maltose, 75% by 2% honey, 91.3% by 3% histidine, 96.9% by 1% heparin, 97.5% by 4% dextrose, 97.9% by 5% lactose, 99.4% by 5% sucrose, 99.5% by 2% gelatin, and 100% by 1-5% glycerol. In narrowing the concentration levels of skim milk to include 1.00, 1.25, 1.50, 1.75, 2.00, 2.25, 2.50, 2.75, and 3.00%, the 2.50% was the optimum level resulting in minimal percent reduction in SE cell viability of 18.9% after exposure to the defined heat stress.