EFFECTS OF CHALLENGE METHODS AND FEEDING ADDITIVES ON ANTIBODY PRODUCTION AND GROWTH INHIBITION OF THE SERUM AGAINST SALMONELLA ENTERITIDIS, S. GALLINARUM AND S. PULLORUM IN CHICKEN

Salmonellosis in humans occurs by consumption of contaminated poultry and their products. To prevent the Salmonella infection in poultry, we investigated the maturity of peritoneal macrophages of chicks, the effect of feeding additives on the IgM and IgG levels and growth inhibition of Salmonella and egg contamination among four inoculation methods. The maximal yield of peritoneal macrophages was in 30- to 33-day-old chicks and intracellular Escherichia coli were eradicated in the macrophages of chicks aged >29-days old. Fungal β-glucan sources and serovars affected the IgM and IgG levels. Complement activity affected IgM measurement and the highest antibody levels were observed against S. Enteritidis compared with S. Pullorum/Gallinarum. Furthermore, β-glucans of Schizophyllum commune and Ganodermaincreased the IgM level against three serovars, while β-glucans of Ganoderma, Taiwanofungus camphoratus, and Botryosphaeria rhodina increased the IgG level against S. Enteritidis and S. Pullorum. In the growth inhibition, β-glucans from S. commune and T. camphoratus increased the inhibition against S. Gallinarum. Supplementation with β-glucan from S. commune in combination with antibiotics and/or herbal medicine or β-glucan from B. rhodina inhibited the growth of S. Pullorum. Feeding with β-glucans from S. commune and Cordyceps inhibited the growth of S. Enteritidis. Among cloacal, oral, intraperitoneal (IP) and intravenous (IV) inoculations, IP inoculation stimulated the maximum antibody level, while S. Enteritidis could not be eradicated from the eggs with the highest antibody level. In conclusion, additives with β-glucan can be used to enhance the immune responses of young and mature chicken against Salmonella infection.