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Humane Harvest

Humane Harvest

Reduce Harvest Stress with AQUI-S

Rested Harvest Procedure

There are many ways to incorporate AQUI-S® into a harvest procedure. The most commercially efficient rested harvest procedure is where anaesthetised fish are supplied to the slaughter area continuously. Continuous flow systems often incorporate staging areas or zones to ensure only fish that are appropriately anaesthetised are available for slaughter. The system below is one example of a continuous flow system. In this system, fish remain in each zone for approximately five minutes before moving to the next. To move the fish between zones, the net lining between the zones is lowered and the fish pushed forward. Fish are only moved forward once all fish have been harvested from Zone 3.

rested harvest technique

rested harvest technique

This rested harvesting design has proven effectiveness and is being used successfully by finfish farms around the world. Farms using this system are able to have a continuous flow. The size and design of the system can be adapted to suit your particular requirements.

The Basic Rested Harvest Technique:


The Crowd
The crowding of fish is the most crucial step involved in a rested harvest. If the crowd is conducted poorly, it will adversely affect the flesh quality. A successful crowd involves careful marshalling of fish into the sedation bath. Fish should be exhibiting normal swimming behavior during this process. There should be no escape response shown as evidenced by agitated swimming behavior and excessive exercise.


Entry into the Bag  
The gusset is slowly lowered to allow fish to swim into the AQUI-S® bag where they are subsequently sedated. Fish should show no reaction or aversion to entering the AQUI-S® bath.


AQUI-S® Application  
The AQUI-S® stock solution can be added directly to the water. This may be prior to the entry of the fish or once fish have entered the sedation bath. A garden sprayer fitted with an extra long wand can be used for the application of AQUI-S®. The tip of the wand is placed beneath the surface to inject the stock solution.


Movement Inside the Bag  
As fish progress through the sedation bag, they steadily become more sedated. Sedated fish can be easily moved within the sedation bag with the use of the internal net lining. As fish are sedated, they do not fight against the movement of the bag.


Removal from the Bag  
If a brail net is being used, it should be enclosed for minimal water loss. The brail is emptied into a tub containing AQUI-S® treated water on the harvest barge. The tub needs to have a return pipe running back to the sedation bag to conserve AQUI-S® treated water. If a fish pump is being employed, it should have a return pipe running back to the sedation bag to conserve AQUI-S® treated water. Agitation of water due to pump action may cause some foaming.


Fish can be killed by either percussion or Iki Jime. There has been significant progress on the design of automated killing methods, and percussion stunners are currently the most effective available. The gill arches should be cut and fish transferred to an ice slurry for bleeding.