Triploidy induced by pressure shock in Arctic charr (Salvelinus alpinus): growth, survival and maturation until the third year

Retention of the second polar body for the production of triploid Arctic ch arr (Salvelinus alpinus) was induced by 65 MPa (650 bar) pressure shocks ap plied 30, 40 or 50 min after fertilization, each shock lasting 5 min. Tripl oid yield (percentage of relative survival to control x percent triploidy) varied from 55 to 100% and it was generally superior to 80. Despite increas ed mortality and decreased growth in diploid charrs during the spawning per iod, growth and survival did not differ between diploid and triploid Arctic charr up to and during their third year of life. Most of the triploid male s had developed testis, but they did not render milt; few triploid females had developed ovaries. Fecundity, of triploid females was low and fertilize d eggs from triploid females did not hatch. (C) 2001 Ifremer/CNRS/Inra/IRD/ Cemagref/Editions scientifiques et medicales Elsevier SAS.