Prevention of fish photobacteriosis. Comparison of the efficacy of intraperitoneally administered commercial and experimental vaccines

Abstract

Two commercial multivalent vaccines against vibriosis, caused by Vibrio anguillarum serotype(s) and photobacteriosis, caused by Photobacterium damsela subsp. piscicida, one with oil adjuvant (AJ) and the other, being an aqueous solution (AV), and an experimental monovalent (Ph. damselae subsp. piscicida) vaccine inactivated with formalin or heat, namely EVF and EVH, were tested in laboratory trials on sea bass (Dicentrarchus labrax) with respect to their efficacy against experimentally induced photobacteriosis.The first trial aiming at high bacterial pressure was carried out 34 days post-vaccination and resulted in 90% mortalities in the control. The relative per cent survival (RPS) of vaccinated fish was calculated at 24, 3.7, 0 and 0 for the AJ, AV, EVF and EVH formulations, respectively. The second trial aiming at medium bacterial pressure was carried out 49 days post-vaccination and resulted in 45% mortalities in the control. The relative per cent survival (RPS) of vaccinated fish was calculated at 100, 92.7, 77.8 and 66.7 for the AJ, EVF, EVH and AV formulations, respectively. Apparently, under both these high and medium bacterial pressure conditions, the commercial vaccine AJ performed better than the commercial vaccine AV, while under medium pressure there was no statistical difference between the performance of EVF and AJ. The measurement of specific antibody titers in sera collected from all fish groups 49 days post-vaccination, showed high levels in the fish vaccinated with the AJ vaccine, almost three times lower levels for the AV and EVF vaccines and even lower levels for the EVH vaccine. Results are discussed with respect to the choices available to mariculture companies in selecting a commercial vaccine against photobacteriosis and possible alternatives, which, if commercially developed, may reduce the cost of vaccination.

Quantitative and qualitative analysis of sea bream,Sparus aurata(L.), humoral immune response, vaccinated with commercial and experimental vaccines against vibriosis and photobacteriosis

“…Specific antibodies titres raised against either of the pathogens were significantly higher from the experimental group that was immunized with the adjuvanted commercial vaccine (AJ). This is in agreement with previous studies (Bakopoulos et al , 2015a, b) and the presence of adjuvant has been shown to have a profound effect on the efficacy of adjuvanted vs aqueous formulations (Gravningen et al , 1998; Lund et al , 2003; Nikoskelainen et al , 2007; Bakopoulos et al , 2015a). This effect is due to stimulation of non-specific immune factors; it has been shown adjuvants induce a strong attraction of different types of leukocytes in the area of vaccination and can have a prolonged effect due to slower release of antigen (Afonso et al , 2005).…”

“…More information cannot be provided because of its proprietary nature. The efficacy of both these products against infection with Phdp has been described before (Bakopoulos et al , 2015a) and field data support the efficacy of both products against Vibriosis. Both these products were purchased and kindly donated by the company Cephalonian Aquaculture for the purposes of this study.…”

“…It is evident that the inclusion of an adjuvant to the formulation which induces a strong attraction of different types of leukocytes in the area of vaccination (Afonso et al , 2005) not only enhanced the production of specific anti-Phdp levels, but also had a positive effect on the repertoire of antigens recognized. This has positive implications on the efficacy of the vaccine, as has been previously recognized (Gravningen et al , 1998; Bakopoulos et al , 2015a). In the study of Hanif et al (2005) sera from sea bream broodstock immunized twice with inactivated whole Phdp bacterial cells reacted with Phdp antigens at the range of 117–34.7 kD, contradicting the reactions we saw in this study.…”

Infectious diseases and treatment solutions of farmed greater amberjack Seriola dumerili with particular emphasis in Mediterranean region

“…Caution should be given therefore for the possible transmission of the pathogen among different Mediterranean farmed species. Commercially available vaccines against Photobacteriosis have been available for quite some time for farmed gilthead seabream and European seabass (Bakopoulos et al, 2015) and effective chemotherapy exists to confront the bacterium (Rigos & Troisi, 2005).…”

Συσχέτιση περιβαλλοντικών παραμέτρων με την εμφάνιση ασθενειών στο εκτρεφόμενο λαβράκι Dicentrarchus labrax, L. 1758 και πρόληψη των ασθενειών αυτών

“…, ενώ η προστασία που παρέχεται μετά τον εμβολιασμό κατά του Phdp είναι αμφισβητήσιμη . (Gravningen et al 2008) και για διδύναμα εμβόλια σε λαβράκι (Bakopoulos et al 2015b). Στα πειράματα που έγιναν στην παρούσα μελέτη, η σοβαρότητα της λοίμωξης όπως αποδείχθηκε από την ποσοστιαία αθροιστική θνησιμότητα των μη εμβολιασμένων ψαριών (μαρτύρων), επηρέασαν τις τιμές RPS που υπολογίστηκε και στις δύο περιπτώσεις και για τα δύο εμβόλια.…”