Oral and intranasal administration of somatostatin DNA vaccine mediated by attenuated Salmonella Enterica Serovar Typhimurium to promote growth of piglets
X.B. Liu,
A.X. Liang,
X.G. Feng,
A.Z. Guo,
C.Y. Ke,
S.J. Zhang,
L.G. Yang
Affiliations
X.B. Liu
Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, People's Republic of China
A.X. Liang
Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, People's Republic of China
X.G. Feng
Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, People's Republic of China
A.Z. Guo
State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, People's Republic of China
C.Y. Ke
Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, People's Republic of China
S.J. Zhang
Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, People's Republic of China
L.G. Yang
Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, People's Republic of China
An attenuated strain of Salmonella typhimurium has been used as a carrier for oral and intranasal genetic immunization. Here, we evaluate the efficacy of a vaccine strain of S. typhimurium. CSO22 (pGM-CSF/SS, plasmid granulocyte-macrophage colony-stimulating factor/somatostatin) expressing two copies of SS genes. A total of 115 piglets, aged 2 months old, were either orally or intranasally immunized against the vaccine strain CSO22 (pGM-CSF/SS) with three dosages (5 × 1010 colony forming units (CFU), 5 × 109 CFU and 5 × 108 CFU). For oral immunization, the specific anti-SS antibodies were detected in the immunized piglets. The levels of SS antibodies in the high-dose immunized group (5 × 1010 CFU) were significantly higher than that in the phosphate buffered saline immunized group (P < 0.01) and 40% of animals were positive in SS antibodies in the high-dose immunized group. Moreover, the weight gain of the high-dose group was increased by 20.86%, 10.26% and 15.30% during 4, 8 and 12 weeks, respectively, after immunization in comparison to the control. For intranasal immunization, the growth of the low-dose group was increased by 10.23% in the whole test period (12 weeks). In conclusion, our results suggest that the recombinant strain could elicit anti-SS antibodies and improve the growth performance of immunized piglets, and that the oral immunization program is better than the intranasal program.