SUMMARY – Effective procedures of vaccination against lactococcosis in rainbow trout (Oncorhynchus mykiss) are still under investigation and the methods currently employed are based on “autovaccines” that are injected intraperitoneally to fish. These vaccines allow a protection for 8 months, when integrated with adjuvants. The bacterial antigenic components involved in the protection are only partially considered by the literature. This investigation concerns the effect of some fractions of Lactococcus garvieae in the development of a protective immune response to the infection. Extracellular products (ECPs), bacterial whole cells (WCs) and membrane antigens (AM) were injected intraperitoneum to 90 g. rainbow trouts. Fish were subsequently submitted to an intraperitoneal challenge with L. garvieae (2.6×105 cfu/individual). The treatments allowed the following relative percentages of survival (RPS): 95% for WCs; 35% for ECPs, 33% for AM. These results suggest that WCs give the best protection, but also ECPs and AM are effective. Samples of serum collected from immunized and control fish were analysed by immunoblotting against the SDS-PAGE/Western Blotting protein profile of each bacterial fraction. The control and immunized fish sera contained immunoglobulins able to bind aspecifically the proteins having a molecular weight of 23, 48 and 102 kDa respectively.
Valutazione della protezione indotta da frazioni antigeniche di Lactococcus garvieae in trota iridea (Oncorhynchus mykiss)
VOLPATTI, Donatella;CONTESSI, Barbara;GUSMANI, Laura;GALEOTTI, Marco
2007-01-01
Abstract
SUMMARY – Effective procedures of vaccination against lactococcosis in rainbow trout (Oncorhynchus mykiss) are still under investigation and the methods currently employed are based on “autovaccines” that are injected intraperitoneally to fish. These vaccines allow a protection for 8 months, when integrated with adjuvants. The bacterial antigenic components involved in the protection are only partially considered by the literature. This investigation concerns the effect of some fractions of Lactococcus garvieae in the development of a protective immune response to the infection. Extracellular products (ECPs), bacterial whole cells (WCs) and membrane antigens (AM) were injected intraperitoneum to 90 g. rainbow trouts. Fish were subsequently submitted to an intraperitoneal challenge with L. garvieae (2.6×105 cfu/individual). The treatments allowed the following relative percentages of survival (RPS): 95% for WCs; 35% for ECPs, 33% for AM. These results suggest that WCs give the best protection, but also ECPs and AM are effective. Samples of serum collected from immunized and control fish were analysed by immunoblotting against the SDS-PAGE/Western Blotting protein profile of each bacterial fraction. The control and immunized fish sera contained immunoglobulins able to bind aspecifically the proteins having a molecular weight of 23, 48 and 102 kDa respectively.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
