Nofima reports

Rapport/Report 34/2015 - English summary

Mørkøre, Turid; Larsson, Thomas; Kvellestad, Agnar Ståle; Koppang, Erling Olaf; Åsli, Magnus; Krasnov, Aleksei; Dessen, Jens-Erik; Moreno, Helena Maria; Valen, Elin Christine; Gannestad, Kjellrun Hoås; Gjerde, Bjarne; Taksdal, Torunn; Bæverfjord, Grete; Meng, Yuqiong; Heia, Karsten; Wold, Jens Petter; Borderias, A.J.; Moghadam, Hooman; Romarheim, Odd Helge; Rørvik, Kjell-Arne

Publication details

Publisher: Nofima AS

Issue: 34/2015

Number of pages: 79

International Standard Numbers:
Printed: 978-82-8296-322-0

Open Access: green


Today, every fifth salmon fillet has “black spots”. Most spots are less than 3 cm in diameter and localized to the abdominal fillet part. “Black spots” occur early in the seawater phase but the prevalence and the size of the spots increase toward slaughter. “Black spots” are associated with local chronic inflammation, scar formation, increased levels of certain minerals and microorganisms. The importance of genetic background and vaccine are not significant. It takes time before melanin is deposited in injured tissue, hence slaughter methods and slaughter stress have no significant impact on development of “black spots”. Farming conditions, water quality, vaccination method, the salmon's health condition and injuries during the farming phase can affect the development of “black spots”.