Treatment or Protection Strategies

Management
SPDV is most certainly endemic in Atlantic salmon farming regions in Europe and possibly world-wide. Good management practices, such as fallowing and all in-all out stocking, have undoubtedly reduced the impact of this disease in recent years but there is no doubt that there would be significant savings to farmers if an effective vaccine was coupled to these measures.

Dietary management has also been applied to reduce stress and aid recovery. Many farms withhold feed from all fish on site for 5-10 days upon suspicion of PD, as there was some circumstantial evidence that this reduced the impact and losses. However, in our experience, it may take  2-3 months for all pens on a site to become infected and this strategy may be causing unnecessary losses in production due to days off feed. If possible, dietary management should be on a cage by cage basis to optimise any effect and reduce consequent growth penalties. Additional vitamin E and C in the diet may aid recovery.

Prophylaxis
A vaccine against PD has been developed by Intervet, Norvax Compact PD, and is available in several markets. Intervet continues to work towards improving the use of the vaccine in various vaccination situations and strategies.