Question

in mid 20th century fish disease cantrolled by using

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Answer 1

Answer:

Duff's report did not result in an immediate landslide of fish vaccination trials in ... the second world war, the preoccupation was with disease control using the newly discovered antibiotics.

Answer 2

Answer:

Dip treatment in 3% common salt for 5- 10 mins. - 1:2000 parts of copper sulphate (CuSo4) for 5- 10 mins. - 1:1000 parts of Potassium permanganate (KMno4) for 5-10 mins until fish shows distress. - 3-5% common salt bath for 5 mins.

Mucus (slime coat) is a physical barrier that inhibits entry of disease organisms from the environment into the fish. It is also a chemical barrier because it contains enzymes (lysozymes) and antibodies (immunoglobulins) that can kill invading organisms.

Explanation:

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