Scientific research proved that physical exercise will also increase the robustness and strengthen the health of fish. Regular training strengthens immune defence and leads to increased life expectancy. Physical fostering of farmed salmon improves the growth rate of the fish and better equips them to cope with disease. Molecular genetic studies show that physical training influences parts of the salmon’s immune system and amongst other things reduces the its inflammation level.
Fisheries and Aquaculture Industry Research Fund (FHF) has initiated two projects about aerobic stamina training of salmon. Scientists from Nofima Marin, the Norwegian Institute for Water Research (NIVA), the Norwegian School of Veterinary Science (NVH) and NTNU’s Faculty of Medicine, in collaboration with Aakvik Settefisk, have studied whether physical training of presmolt gives a more robust salmon.
The results of a bath challenge test for infectious pancreatic necrosis (IPN) show that the group that had completed six weeks’ of swimming exercise had a survival rate that was more than 10 percent better than the control group. This shows that physical exercise increases disease resistance in fish. The study also showed that fish that had undergone training had significantly better growth rates than fish that had not undergone training.
The fact that fish that that were subjected to physical exercise as presmolt salmon cope better in a challenge test than fish that have not undergone such swimming exercise indicates that the physical training has had a positive effect on the immune system of the fish. Studies of 1800 genes showed that other parts of the immune system were positively influenced by physical training.
Research shows that training is beneficial for farmed fish, the next questions will be how much, how often, how hard and in which way fish should be trained. Overtraining is a well known term within the field of exercise physiology. The concept of overtraining means that the body has insufficient time to recover between training sessions. This can lead to a chronic inhibition of the immune system and increased inflammation levels in the body.
