Fakulta rybářství Jihočeská univerzita Fakulta rybářství Jihočeská univerzita University of South Bohemia University of South Bohemia in České Budějovice in České Budějovice 2018 Selected aspects of intensively cultured European whitefish (Coregonus maraena, Bloch) and peled (Coregonus peled, Gmelin) Vybrané aspekty intenzivního chovu síha marény (Coregonus maraena, Bloch) a peledě (Coregonus peled, Gmelin) , Coregonus maraena Coregonus , Gmelin) Coregonus peled Coregonus Roman Šebesta Selected aspects of intensively cultured European whitefish ( whitefish European cultured aspects of intensively Selected Bloch) and peled ( ISBN 978-80-7514-080-7 Czech Republic, Vodňany, 2018 Roman Šebesta Fakulta rybářství Jihočeská univerzita University of South Bohemia in České Budějovice Selected aspects of intensively cultured European whitefish (Coregonus maraena, Bloch) and peled (Coregonus peled, Gmelin) Vybrané aspekty intenzivního chovu síha marény (Coregonus maraena, Bloch) a peledě (Coregonus peled, Gmelin) Roman Šebesta Czech Republic, Vodňany, 2018 Chapter 1 I, Roman Šebesta, thereby declare that I wrote the Ph.D. thesis myself using results of my own work or collaborative work of me and colleagues and with help of other publication resources which are properly cited. I hereby declare that, in accordance with the § 47b Act No. 111/1998 Coll., as amended, I agree with publicizing of my Ph.D thesis in full version electronically in a publicly accessible part of the STAG database operated by the University of South Bohemia in České Budějovice on its web sites, with keeping my copyright to the submitted text of this Ph.D. thesis. I also agree so that the same electronic way, in accordance with above mentioned provision of the Act No. 111/1998 Coll., was used for publicizing reviews of supervisor and reviewers of the thesis as well as record about the progress and result of the thesis defence. I also agree with compering the text of my Ph.D. thesis with a database of theses “Theses.cz” operated by National Register of university theses and system for detecting of plagiarisms. In Vodňany 17th July, 2018 - 4 - Supervisor: Vlastimil Stejskal, Ph.D. University of South Bohemia in České Budějovice (USB) Faculty of Fisheries and Protection of Waters (FFPW) Institute of Aquaculture and Protection of Waters (IAPW) Laboratory of Controlled Reproduction and Intensive Fish Culture South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses Husova třída 458/102, 370 05 České Budějovice, Czech Republic Consultant: Assoc. Prof. Jan Mráz University of South Bohemia in České Budějovice (USB) Faculty of Fisheries and Protection of Waters (FFPW) Institute of Aquaculture and Protection of Waters (IAPW) Laboratory of Nutrition South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses Na Sádkách 1780, 370 05 České Budějovice, Czech Republic Head of Laboratory of Controlled Reproduction and Intensive Fish Culture: Vlastimil Stejskal, Ph.D. Dean of Faculty of Fisheries and Protection of Waters: Prof. Pavel Kozák Board of doctorate study defence with reviewers: Assoc. Prof. Josef Matěna – head of the board Prof. Petr Ráb – board member Prof. Otomar Linhart – board member Assoc. Prof. Martin Kocour – board member Prof. Lukáš Kalous – board member Assoc. Prof. Ondřej Slavík – board member Assoc. Prof. Zdeněk Adámek – board member Dr. Daniel Żarski – University of Warmia and Mazury, Olsztyn, Poland – reviewer Dr. Francesco Gai – National Research Council Institute of Sciences of Food Production, Turin, Italy – reviewer Date, hour and place of Ph.D. defence: 12th December, 2018 at 9:00 in USB, FFPW, RIFCH, Vodňany, Czech Republic Name: Roman Šebesta Title of thesis: Selected aspects of intensively cultured European whitefish Coregonus( maraena, Bloch) and peled (Coregonus peled, Gmelin) Vybrané aspekty intenzivního chovu síha marény (Coregonus maraena, Bloch) a peledě (Coregonus peled, Gmelin) Ph.D. thesis, USB FFPW, RIFCH, Vodňany, Czech Republic, 2018, 139 pages, with the summary in English and Czech. Graphic design & technical realisation: JENA Šumperk, www.jenasumperk.cz ISBN 978-80-7514-080-7 - 5 - Chapter 1 CONTENT CHAPTER 1 7 General introduction CHAPTER 2 25 The effect of light intensity and tank wall colour on survival and growth of peledCoregonus peled Gmelin 1788 larvae CHAPTER 3 41 Effect of temperature on growth and survival of maraena whitefishCoregonus maraena (Bloch 1779) larvae in controlled conditions CHAPTER 4 51 Effect of stocking density on growth and survival of maraena whitefishCoregonus maraena (Bloch 1779) larvae in controlled conditions CHAPTER 5 63 Effect of feeding strategy on survival, growth, intestine development, and liver of maraena whitefishCoregonus maraena (Bloch 1779) larvae cultured under RAS conditions CHAPTER 6 83 Combined effect of weaning time and co-feeding duration on growth and survival of peled Coregonus peled (Gmelin) larvae CHAPTER 7 93 Combined effect of weaning time and co-feeding duration on growth and survival of peled Coregonus peled (Gmelin) larvae CHAPTER 8 103 Prevalence of deformities in intensively reared peled Coregonus peled and comparative morphometry with pond-reared fish CHAPTER 9 113 General discussion 115 English summary 129 Czech summary 131 Acknowledgements 133 List of publications 134 Training and supervision plan during study 137 Curriculum vitae 139 - 6 - CHAPTER 1 GENERAL INTRODUCTION - 7 - Chapter 1 General introduction 1.1. COREGONIDS Whitefish Coregonus( sp.) have a northern circumpolar distribution with occurrence in North America (Canada), Asia (Chukchi peninsula) and Europe (British Isles) (Bodaly et al., 1991). Coregonidae subfamily belongs to the Salmonidae family. TheCoregoninae subfamily is actually divided into genus Coregonus, Prosopium, Stenodus and Leucichthys including marine, anadromous and freshwater species. Coregonus evolved in the lake and stream area of northwest Eurasia, Stenodus and Prosopium originated in the rivers of Siberia and northwest America respectively, and Leucichthys became differentiated in the lake-studded area of northeast America (Smith, 1957). Some species are extinct following the formation of hybrids and habitat modification. The genetic integrity of several wild populations and species is threatened. This leads to uncertainty and confusion in the classification and correct taxonomy of this fish genus. There exist a lot of speculations about number of coregonid species and subspecies which differ in size, shape, number of gill rakers, scales etc. In several lakes, several populations (up to 11 in Lake Onega) are morphologically and genetically distinct. They live in sympatry, and they have different habitat, ecology, preffered prey and spawning season requirements. These populations negate the idea that only single species could be involed within one lake (Kottelat and Freyhof, 2007). Beveridge (1989) mentioned 20 - 30 species belonging to the genus Coregonus. Hanel and Novák (2007), state 67 species of genus Coregonus and 6 species of genus Prosopium. Until 1950, 92 subspecies of whitefish had been described in Europe, and 300 local forms had been described all over the world (Brylińska, 2000). 1.2. COREGONIDS IN THE CZECH REPUBLIC Coregonids farming has a long history in the Czech Republic. In 1882, Maraena whitefish (Coregonus maraena) were introduced to the Czech Republic, whereas peled (Coregonus peled) were introduced from Siberia in 1970. Both species are suitable for polyculture with common carp (Cyprinus carpio) in deep ponds with cool water conditions (Hochman, 1987). In the past, the production was stable and high, but due to the global threats including predation by the great cormorant (Phalacrocorax carbo) (Suter, 1997), overfishing (Jackson et al., 2001), hybridization (Luczynski et al., 1992), eutrophication (Thomas and Eckmann, 2007), impairments of natural spawning sites (Winfield et al., 2004), pollution and environmental changes (Walther et al., 2002) the yield has rapidly declined. In 1997, market- size whitefish production ranged approximately 140 tons (Annual report 2002, Czech Ministry of Agriculture). The annual production decreased dramatically to 24 tons in 2007 (Annual report 2011, Czech Ministry of Agriculture) and to 4 tons in 2016 (Annual report 2017, Czech Ministry of Agriculture). The demand for coregonids is still high but current whitefish production do not sufficiently support internal fish market (general knowledge). Production of whitefish in intensive culture can mitigate the decline in wild populations from lakes and ponds. Furthermore, artificial production provides juvenile fish for re-stocking lakes, as well as for market demands (Heikinheimo-Schmid, 1992). Nowadays, whitefish are candidates for inland freshwater aquaculture, particularly in local markets in central and east Europe (Turkowski, 1999) and they show potential for rearing in RAS systems (Siikavuopio et al., 2012). They are well known for high palatability of their flesh and high content of polyunsaturated fatty acids (Orban et al., 2006). On the other hand, rearing of peled in RAS is a recent innovation, and optimization is necessary to standardize aspects of culture, including weaning of larvae from live feed to artificial diet (Stejskal et al., 2017). - 9 - Chapter 1 1.2.1. Peled (Coregonus peled) Peled has been considered valuable commercial species of coldwater aquaculture in Russia. This species has been introduced both within and far outside its natural range, for instance Estonia, Lithuania,