Give TWO purposes of using drugs in aquaculture.
to control mortality associated with bacterial diseases or infestation density of parasites, sedate or anesthetize fish, induce spawning, change gender.
Give 2 water quality problems.
High turbidity, pesticide, high nutrient, high organic matter, acidic water, industrial pollusion.
Give THREE chemicals used for water treatment.
Lime CaCO3 (calcium carbonate) Hydrated lime Ca(OH)2 (calcium hydroxide) Fertilizers, zeolite, salt.
2 examples of lime
Lime CaCO3 (calcium carbonate) Hydrated lime Ca(OH)2 (calcium hydroxide) Dolomite
2 reasons for liming.
Kill parasites, raise pH of acidic water, increase alkaline in water and mud, enhance fertilization.
Function of salt in aquaculture.
As a parasiticide to control external parasites of freshwater fish, Prevent and treat nitrite poisoning or “Brown Blood Disease”, Transport of handle fish.
3 types of breeding in aquaculture
Natural, semi-natural, artificial breeding.
2 benefits of artificial breeding.
Better rates of fertilization and hatching. Protection against enemies and unfavourable environmental conditions. Better conditions for growth and survival.
How to differentiate fish male and female?
Genital part.
What is hypophysation?
injection of the pituitary gland extract that induces breeding in fish.
Purpose of ovaprim.
Induce maturation within a spawning season Advance spawning date Coordinate and synchronize spawning times Increase milt production including increased sperm
Difference between disinfectant and antiseptic.
Disinfectant: non-living matter, antiseptic: living organisms.
Give 2 chemicals to disinfect the tank.
Chlorine, Iodophor
Why Malachite Green is banned?
MG - LMG - carcinogenic
2 chemicals to remove unwanted species.
rotenone, tea seed cake, saponin
