Follow-up of hatchery rotifer cultures with regard to their genetic identity

: Papakostas S, De Wolf T, Triantafyllidis A, Vasileiadou K, Kanellis D, Cecconi P, Kappas I, Abatzopoulos TJ

Publisher: ARISTOTLE UNIV THESSALONIKI

: 2007

Journal of Biological Research

: JOURNAL OF BIOLOGICAL RESEARCH-THESSALONIKI

: J BIOL RES-THESSALON

: 7

: 41

: 49

: 9

: 1790-045X

Brachionus sp. rotifers are widely used in large numbers for larval rearing in fish industry. By practice, cultured rotifers are discriminated on the basis of their body size. Recently however, marked polymorphism has been uncovered with the use of molecular markers. Rotifers of the same size but of distinct genetic profiles have been shown to differ in environmental preferences. Thus, mass culturing practices in hatcheries should be re-considered. In this study, we have followed a number of experimental cultures from an Italian hatchery. The genetic composition of the cultures was recorded and it was revealed that a single Brachionus biotype was prevalent in all cultures. Results indicate that the few observed crashes occurred soon after upscaling. Diet change seems to be a possible factor leading to this outcome. In a single occasion, contamination was observed but the co-existence of different Brachionus types did not affect culture performance. In the future, detailed joint analyses of the genetic identity and culture preferences of the different Brachionus rotifers will provide useful insights into performance-related problems in hatcheries.