Testing of vaccines against mouthrot caused by infections of T. maritimum in Atlantic salmon smolts
The purpose of the experiment is to test different vaccines to prevent infections with Tenacibaculum maritimum, which is a significant disease and welfare problem in Atlantic salmon production in Western Canada. Mouthrot infections have a significant impact on the industry in Western Canada due to the need for antibiotics to treat the disease. Previous fish experiments have shown that the disease can be replicated in lab conditions with certain isolates of T. maritimum using a bath infection model. This experiment aims to use this bath infection model to test the efficacy of a number of vaccines against the bacteria.
A total of 1481 Atlantic salmon will be a part of the experiment. 30 fish will be used in a pre-experiment to confirm the infection protocol and 15 fish will be used to test antibody levels pre-immunisation. The other 1436 fish will all be immunised either with a control or with a vaccine against a Western Canadian strain of T. maritimum. Smoltification will be triggered so that half of the fish are ready to be transferred to saltwater at 8 weeks post-immunisation and the other half at 12 weeks. At these two time points 60 fish will be sampled to measure antibody levels and the fish will be transferred to saltwater. 36 fish from the 8 weeks group will also be sampled to determine smolt readiness. After 24 hours of acclimation to saltwater, the fish will be exposed to T. maritimum using the protocol developed by the University of Bergen. Some fish will experience disease. To reduce their suffering and discomfort to a minimum strict surveillance of humane endpoints will be enforced. The objectives of the experiment cannot be carried out without the use of laboratory fish. The number of fish is reduced to a minimum for what is necessary to provide sufficient quality data.
A total of 1481 Atlantic salmon will be a part of the experiment. 30 fish will be used in a pre-experiment to confirm the infection protocol and 15 fish will be used to test antibody levels pre-immunisation. The other 1436 fish will all be immunised either with a control or with a vaccine against a Western Canadian strain of T. maritimum. Smoltification will be triggered so that half of the fish are ready to be transferred to saltwater at 8 weeks post-immunisation and the other half at 12 weeks. At these two time points 60 fish will be sampled to measure antibody levels and the fish will be transferred to saltwater. 36 fish from the 8 weeks group will also be sampled to determine smolt readiness. After 24 hours of acclimation to saltwater, the fish will be exposed to T. maritimum using the protocol developed by the University of Bergen. Some fish will experience disease. To reduce their suffering and discomfort to a minimum strict surveillance of humane endpoints will be enforced. The objectives of the experiment cannot be carried out without the use of laboratory fish. The number of fish is reduced to a minimum for what is necessary to provide sufficient quality data.