Finfish Breeding and Hatchery Management

5.3.3. Use of anaesthetics and disinfectants

Unit 5 - Fish seed rearing techniques

5.3.3. Use of anaesthetics and disinfectants in fish breeding and live transport

• Sedation would reduce the metabolic activity and decrease the oxygen consumption by fish. It also reduces the excretion of ammonia, carbon dioxide and other toxic wastes.
• It controls the excitability of the fish, thereby reducing the chances of injury and the time required for handling them.
• However, care should be taken in selecting the sedative and also its dosage. Sedation should be such that it should not totally suppress the escape reaction of fish and it should be possible to revive the fish quickly.
• Some of the sedatives like MS-222, novocaine, amobarbital, thiouracil, quinaldine, hydroxyl quinaldine, sodium amytol , etc. are found to be adequate for the successful transport of fish seed and brood-fish.
• Jhingran and Pullin (1988) stated that while fingerlings need not be essentially anaesthetized before being transported, brood fish must be anaesthetized.

Use of antiseptics and antibiotics

• The accidental introduction of infectious diseases and parasites along with fish consignments is a possibility that must be guarded against.
• This calls for prophylactic measures like the use of antiseptics and antibiotics in the transport medium or short-term bath prior to transport.

The recommended chemicals and their dosages are as follows:

Chemical	Dosage (mg/l)
1. Acriflavine	10ppm
2. Methylene blue	2ppm
3. CuSO4	5ppm
4. KMnO4	3ppm
5. Chloromycetin	8-10ppm
6. NaCl	3%
7. Formalin	15ppm