TY - JOUR
T1 - Effect of size and temperature at vaccination on immunization and protection conferred by a live attenuated Francisella noatunensis immersion vaccine in red hybrid tilapia
AU - Soto Martinez, Esteban
AU - Brown, Nicholas
AU - Gardenfors, Zackarias O.
AU - Yount, Shaun
AU - Revan, Floyd
AU - Francis, Stewart
AU - Kearney, Michael T.
AU - Camus, Alvin
PY - 2014/12/1
Y1 - 2014/12/1
N2 - Francisella noatunensis subsp. orientalis (Fno) is a pleomorphic, facultative intracellular, Gram-negative, emerging bacterial pathogen of marine and fresh water fish with worldwide distribution. In this study, the efficacy of an attenuated Fno intracellular growth locus C (iglC) mutant was evaluated for use as a live immersion vaccine, when administered to hybrid tilapia at two different stages of growth (5g fry and 10g fingerlings) and at two temperatures (25°C and 30°C). To determine vaccine efficacy, mortality, days to first death, and Fno genome equivalents (GE) in the spleens of survivors, as well as serum and mucus antibody levels, were evaluated after 30d in fish challenged with a wild type virulent strain. Both size and temperature at vaccination played an important role in immunization and protection. Fry vaccinated at 25°C were not protected when compared to non-vaccinated fry at 25°C (p=0.870). In contrast, 5g fry vaccinated at 30°C were significantly protected compared to non-vaccinated fry at 30°C (p=0.038). Although lower mortalities occurred, 10g fingerlings vaccinated at 25°C were not protected, compared to non-vaccinated fingerlings at 25°C (p=0.328), while, 10g fingerlings vaccinated at 30°C were significantly protected, compared to non-vaccinated fingerlings at 30°C (p=0.038). Additionally, overall mortality of 5g fish was significantly higher than in 10g fish. Mortality was also significantly higher in fish subjected to a 30 to 25°C temperature change one week prior to challenge, than in fish maintained at the same temperature during vaccination and challenge. This information demonstrates that both temperature and size at vaccination are important factors when implementing immunization prophylaxis in cultured tilapia.
AB - Francisella noatunensis subsp. orientalis (Fno) is a pleomorphic, facultative intracellular, Gram-negative, emerging bacterial pathogen of marine and fresh water fish with worldwide distribution. In this study, the efficacy of an attenuated Fno intracellular growth locus C (iglC) mutant was evaluated for use as a live immersion vaccine, when administered to hybrid tilapia at two different stages of growth (5g fry and 10g fingerlings) and at two temperatures (25°C and 30°C). To determine vaccine efficacy, mortality, days to first death, and Fno genome equivalents (GE) in the spleens of survivors, as well as serum and mucus antibody levels, were evaluated after 30d in fish challenged with a wild type virulent strain. Both size and temperature at vaccination played an important role in immunization and protection. Fry vaccinated at 25°C were not protected when compared to non-vaccinated fry at 25°C (p=0.870). In contrast, 5g fry vaccinated at 30°C were significantly protected compared to non-vaccinated fry at 30°C (p=0.038). Although lower mortalities occurred, 10g fingerlings vaccinated at 25°C were not protected, compared to non-vaccinated fingerlings at 25°C (p=0.328), while, 10g fingerlings vaccinated at 30°C were significantly protected, compared to non-vaccinated fingerlings at 30°C (p=0.038). Additionally, overall mortality of 5g fish was significantly higher than in 10g fish. Mortality was also significantly higher in fish subjected to a 30 to 25°C temperature change one week prior to challenge, than in fish maintained at the same temperature during vaccination and challenge. This information demonstrates that both temperature and size at vaccination are important factors when implementing immunization prophylaxis in cultured tilapia.
KW - Francisella noatunensis
KW - Francisellosis
KW - Temperature
KW - Tilapia
KW - Vaccine
UR - http://www.scopus.com/inward/record.url?scp=84910615444&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84910615444&partnerID=8YFLogxK
U2 - 10.1016/j.fsi.2014.10.009
DO - 10.1016/j.fsi.2014.10.009
M3 - Article
C2 - 25462454
AN - SCOPUS:84910615444
VL - 41
SP - 593
EP - 599
JO - Fish and Shellfish Immunology
JF - Fish and Shellfish Immunology
SN - 1050-4648
IS - 2
ER -