Page 60 - Studio International - May 1974

swim in the sea-water breeding-grounds. These be taken. It has by no means proved easy to conditions for micro-organisms that consume
can be compared to a sound which is barricaded procure brood-stock and subsequently to keep quantities of oxygen. At the worst, these factors
at both ends by gratings in a concrete it alive until it is ready to spawn. Up to the can result in shortage of oxygen and
framework. smolt stage the young salmon is very prone to development of hydrogen sulphide. This is
The salmon is now fed with wet-pellet food attacks of sickness and to parasites, especially particularly a danger for the water on the
consisting of carefully chosen ingredients. The when the temperature rises in the summer. bottom. Changes of weather can cause these
salmon's natural diet is kept to as far as possible, For the hazards of breeding up to the smolt layers to rise and in severe cases be toxic
but with vitamins added. Nourishment alone is stage there are now, however, adequate enough to kill the fish. At the Mowi plants a
not enough to produce a first-class product. remedies, both medicinal and practical. regular oxygen check is taken, also from the
The water must be clean and rich in oxygen. Salt-water breeding is still a little-known bottom strata. In addition, frequent control is
In order to keep the quality of the water at its field. In the initial stages sea-birds are a grave carried out by frogmen. The salt content and
best, the company has installed pumps to problem, and also outsider fish which probably the flow of currents are also checked regularly.
increase the water replacement. feed on the young salmon. Neither can a certain Samples of salmon are sent at regular intervals
Although many difficulties have been cannibalism among the salmon be excluded. to Norges Veterinaerhøyskole (Norwegian
overcome, and the company has begun In addition to nutrition, environment is an Veterinary College) for control. q
marketing salmon for consumption, there are extremely important factor. Food wastage and Courtesy Thor Mowinckel
still plenty of problems to be faced and risks to fish excrement provide good growing

(Top left) Overall shot of Freshwater Plant (Above centre) Mowinckel and staff catching small
quantity of salmon to check if ready to spawn
(Top centre) Loading boat with nets to catch salmon
for testing and finding spawners (Above) Hatchery of last May's eggs

(Top right) Hatchery of last May's eggs, checking for (Left) Testing quality and quantity of spawn which
size, colour, growth, etc. (Detail) will be tested in laboratory later
(Above) Mixing up food for salmon

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