K. B. Davis
J.A. Jenkins
Torrans E. Les
A.-R.A. El Gamal
1999
<p><span> Induction of triploidy and tetraploidy in Nile tilapia, </span><i>Oreochromis niloticus</i><span>, was investigated by heat shock, cold shock, hydrostatic pressure, and/or chemicals (cytochalasin A, B, and D). Additionally, efficacy of combined protocols was determined. Heat shock 10 min after fertilization induced triploidy when incubation temperature was 24 C but not when incubation temperature was 31 C. Heat shock of 40–41 C at 4–6 min after fertilization was effective in inducing up to 100% triploidy with hatchability similar to controls. Cold shock at 13 C for 45 min five min after fertilization induced 85–100% triploids. Heat shock and multiple heat shocking were the most effective treatments for the induction of tetraploidy. Two heat treatments of 41 C applied at 65 and 80 min after fertilization for 5 min each produced approximately 80% tetraploidy in hatched fry. Immersion of fertilized eggs in cytochalasin A, B, or D at concentrations up to 10 μg/L applied at various times and durations was ineffective in inducing triploidy or tetraploidy.</span></p>
application/pdf
10.1111/j.1749-7345.1999.tb00875.x
en
World Aquaculture Society
Induction of triploidy and tetraploidy in Nile tilapia, Oreochromis niloticus (L.)
article