Ornamental Fish Production and Management (1+1)

13.1.4 Conditioning of fish for packaging

Three stages :

1. Prophylactic treatment

2. Starvation

3. Pre-packing

Prophylactic treatment :

1 day to 1 week.

Need of prophylactic treatment :

To prevent post-shipment mortality, prophylactic treatment is essential. Post-shipment mortality is partly associated with less stress resistance of fish. Hence resistance of fish to stress has to be enhanced by nutritional prophylaxis and health prophylaxis.

Nutritional prophylaxis :

The ornamental fishes for export should be resistant to stress. Hence fish should be given nutritious feed for developing strong fish. Feed supplementation of vitamin C enhances stress resistance in fish.

Health Prophylaxis :

Healthy fishes alone should be transported in order to avoid mortality. Even infection is mild (harmless infection) the fishes should not be selected for export. When fishes are exposed to abnormal situation stress is unavoidable. Transportation creates stress. If fishes with mild infection are selected for transport corticosteroid level in plasma will be elevated and therefore immune suppresiveness results. It increases vulnerability of the fish to pathogens. Hence even harmless infection may become lethal. Therefore only healthy fishes should be selected for transport. In order to enhance health the immunity of fish should be enhanced by suitable feeds.

Starvation :

To reduce amount of excreta during transport (1-2 days).

Pre-packing :

Fishes are placed in air-conditioned room at 22-23^oC to enable them to acclimate packing conditions, crowding and low water temperature. Fish that fails to adapt to the packaging conditions and show signs of sickness are eliminated.

Acclimation and recovery of fish after shipment :

After shipment the fishes should not be stocked directly in the aquarium tank. The fishes should be acclimatized for the new environment. The fish bag should be floated for 30 minutes to equalize the temperature of water.