Arktika paalia (Salvelinus alpinus) kasvatamine Eestis
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Kuupäev
2012
Kättesaadav alates
ainult raamatukogus, only in library
Autorid
Ajakirja pealkiri
Ajakirja ISSN
Köite pealkiri
Kirjastaja
Abstrakt
Arktika paalia Salvelinus alpinus, on levinud Põhjapoolkera külmades arktilistes vetes.
Ta on hinnatud vääriskala ja tema kasvatamine Rootsi, Soome jt maade kalakasvandustes
on algjärgus. Eestis on arktika paaliat kasvatatud alates 1990-ndatest aastatest
erinevatesse kasvandustesse imporditud silmtäpis marjast või noorkalana.
Kalakasvatustehnoloogilised kogemused tema paljundamise ja vastsete kontrollitud
tingimustes kasvatamise kohta meie oludes puuduvad. Käesoleva töö eesmärk oli Simuna
Ivaxi kalakasvandustes kasvatatud arktika paalia paljundamise tulemuste põhjal hinnata
selle kala noorjärkude kasvu ja ellujäämist Eesti tingimustes.
Arktika paalia paljundamiseks kasutati 2005-ndal aastal Soomest Saimaa
kalauurimis- ja kasvatuskeskusest Mõdriku kalakasvandusse ühesuvistena toodud ja
2009-ndaks aastaks suguküpsuse saavutanud kalu.
Paljundamise, inkubeerimise ja kasvatamise andmed koguti novembrist 2009 kuni
märtsini 2012 kahes OÜ Simuna Ivax kalakasvanduses. 2009-nda aasta novembris saadi
Mõdriku kalakasvanduses juhuslikult valitud suguküpsetelt 41 emaselt mari ja 44 isaselt
paalialt niisk. Mari viljastati ja inkubeeriti Äntu kalakasvanduses. Emaskalade viljakuse
näitajad kõikusid laiades piirides, 430-2585 marjatera 1 keha kilo kohta. Samuti kõikus
niisa kogus, kuid spermide aktiivsus oli stabiilselt hea (2,5).
Mitme emase mari viljastati portsjonitena koos mitme isase seguniisaga ja pandi
inkubeeruma haudeaparaatidesse. Temperatuuril 4,1 oC kestis inkubeerumine 107
ööpäeva. Mari jõudis silmtäpi staadiumi 41. päevaks ja koorumine algas 100. päeval
peale viljastamist.
Marja inkubeerimisaegse suremuse kõrgtase jäi esimese inkubatsioonikuu
algusesse, kus kadu oli ligi 2500-3500 marjatera (ca 2 %) ööpäevas, mis kuu lõpupoole
langes ja jäi püsima 1000 piirimaile (1 %) ööpäevas. Kokku suri 88 päeva jooksul 120
000 marjaterast 86 800, mis teeb 72 % kogu viljastatud marjast.
Eelvastsete rebukoti tagavara hakkas ammenduma 67 päeva peale koorumist,
samal ajal lasti vastsed haudekastidest suuremasse vanni ja neid hakati kuivsöödaga
sööma õpetama. Kasvatamisaegset noorkalade kadu hinnati surnud isendite arvu põhjal.
Suremus oli katse alguses eelvastsete rühmas 14 tk päevas, mis vähenes kala kasvades.
Vastseeas (vanus kuni 80 päeva) püsis keskmine suremus 7 isendit päevas. Maimude eas
oli suremus 3-4 isendit päevas. Jõudes keskmise kaaluni 1 gramm, kalade hukkumine
praktiliselt lõppes (1 surnu viie ööpäeva jooksul). Noorkalad transporditi 8 grammistena
edasiseks kasvatamiseks Äntust Mõdrikusse, kus suuri probleeme pole esinenud.
Paaliate õpetamine kuivsööta tarbima pikka harjutamisaega ei nõudnud.
Probleemiks oli ebaühtlane kasv ja kannibalism.
Arktika paalia paljundamine ja kasvatamine Eesti tingimustes on võimalik, kui on
olemas sobivad kasvatustingimused, millest olulisim on hapnikurikas, puhas ja külm (alla
15 oC) vesi. Maimud kasvasid Simuna Ivaxi kasvanduses 1 grammiseks 160 päevaga, mis
on 100 päeva kauem kui Johnston’i (2002) poolt kirjeldatud 60 päeva. Maimude aeglast
kasvu ja marja suurt suremust esimestes katsetes võib seletada vähestest kogemustest
tingitud vigadest võtetes, sh noorte, juhuslikult valitud ja vähekvaliteetsete sugukalade
kasutamisega. Välistatud pole inbriidingu mõju marja ellujäämusele ja noorkalade
elujõule. Et tagada väiksem marja kadu inkubeerimisel, peaks kalakasvataja olema
hoolsam erinevate veeparameetrite jälgimisel ja fikseerimisel ning võimalikult vähe oma
tegevusega inkubeerivat marja häirima.
The Arctic charr Salvelinus alpinus is common cold-water fish in the northern hemisphere. He is appreciated valuable fish and his farming in Swedish, Finnish and other countries fish farms is at the early state. In Estonia the Arctic charr has been farmed in different farms since 1990-s as imported eyed stage ova or young fish. There are no fish farming technological experiences concerning the Arctic charr reproduction and controlled larvae farming in our conditions. The aim of the thesis was to estimate the Arctic charr fingerlings growth and survival on the basis of reproduction experiences from Simuna Ivax fish farm. Fishes from Finnish Saimaa Fish Research and Farming Centre were used for the Arctic charr reproduction. These fishes were brought to Mõdriku fish farm in 2005 as one-summer old and reached their sexual maturation in 2009. Reproduction, incubation and farming data was gathered from November 2009 until March 2012 in two Simuna Ivax fish farms. In November 2009 41 sexually matured female and 44 male charrs were randomly selected from Mõdriku fish farm for roe and milt that was inseminated and incubated in Äntu fish farm. The females’ fertility rates varied substantially, ranging from 430 to 2585 eggs per kilo of fish weight. The milt amount ranged but the activity was evenly good. Mixed roe was inseminated in portions with male milt mix and were put to incubate in to the incubation trays. Incubation lasted 107 days at 4,1 oC. After 41 days the roe became the eyed stage and after 100 day the hatching began. Roe’s incubation time fatality rate was higher in the beginning of the first incubation month, the loss was then approximately 2500-3500 eggs (2%) per day. In the end of the month the fatality rate decreased within 2 weeks to 1000 (1%) eggs per day. Altogether, from 120 000 eggs 86 800 died within 88 days that is 72 % from whole roe. By 66 day after the hatching the supply of the newly hatched alevins yolc sac started to run down. 67 days after the hatching, the larvae were put from hatching trays and feeding with dry food started. Young fish loss during the breeding time was estimated on the basis of dead individuals. The newly hatched alevins group fatality rate was 14 per day at the beginning of the experiment but decreased with fish growth. In fry stage (up to 80 days in age) the fatality rate was 7 individuals per day. Fingerling fish stage fatality rate was 3-4 individuals per day. After obtaining the 1 g weight (160 days after hatching) the dying stopped (1 dead per 5 day). From Äntu 8 g weight young fishes were transported to Mõdriku where no major problems have occurred. There was no need for long dry food eating training period, but the problem was uneven growth and cannibalism. The Arctic charr reproduction and farming in Estonia is possible in case of appropriate farming conditions from which the most important is clean, cold (below 15 °C), oxygen rich water. Young fish in Simuna Ivax farm weighted 1 g after 160 days that is however 100 days more than Johnston (2002) experience. The causes of young fish slow growth and roe’s high fatality rate in first experiments could be the early state technology and young randomly selected brood fishes with low quality. Also the effect of inbreeding to roe’s survival and young fish vitality cannot be excluded. Roe’s survival during the incubation could be better in case of more consistent surveillance over water parameters and less disturbance.
The Arctic charr Salvelinus alpinus is common cold-water fish in the northern hemisphere. He is appreciated valuable fish and his farming in Swedish, Finnish and other countries fish farms is at the early state. In Estonia the Arctic charr has been farmed in different farms since 1990-s as imported eyed stage ova or young fish. There are no fish farming technological experiences concerning the Arctic charr reproduction and controlled larvae farming in our conditions. The aim of the thesis was to estimate the Arctic charr fingerlings growth and survival on the basis of reproduction experiences from Simuna Ivax fish farm. Fishes from Finnish Saimaa Fish Research and Farming Centre were used for the Arctic charr reproduction. These fishes were brought to Mõdriku fish farm in 2005 as one-summer old and reached their sexual maturation in 2009. Reproduction, incubation and farming data was gathered from November 2009 until March 2012 in two Simuna Ivax fish farms. In November 2009 41 sexually matured female and 44 male charrs were randomly selected from Mõdriku fish farm for roe and milt that was inseminated and incubated in Äntu fish farm. The females’ fertility rates varied substantially, ranging from 430 to 2585 eggs per kilo of fish weight. The milt amount ranged but the activity was evenly good. Mixed roe was inseminated in portions with male milt mix and were put to incubate in to the incubation trays. Incubation lasted 107 days at 4,1 oC. After 41 days the roe became the eyed stage and after 100 day the hatching began. Roe’s incubation time fatality rate was higher in the beginning of the first incubation month, the loss was then approximately 2500-3500 eggs (2%) per day. In the end of the month the fatality rate decreased within 2 weeks to 1000 (1%) eggs per day. Altogether, from 120 000 eggs 86 800 died within 88 days that is 72 % from whole roe. By 66 day after the hatching the supply of the newly hatched alevins yolc sac started to run down. 67 days after the hatching, the larvae were put from hatching trays and feeding with dry food started. Young fish loss during the breeding time was estimated on the basis of dead individuals. The newly hatched alevins group fatality rate was 14 per day at the beginning of the experiment but decreased with fish growth. In fry stage (up to 80 days in age) the fatality rate was 7 individuals per day. Fingerling fish stage fatality rate was 3-4 individuals per day. After obtaining the 1 g weight (160 days after hatching) the dying stopped (1 dead per 5 day). From Äntu 8 g weight young fishes were transported to Mõdriku where no major problems have occurred. There was no need for long dry food eating training period, but the problem was uneven growth and cannibalism. The Arctic charr reproduction and farming in Estonia is possible in case of appropriate farming conditions from which the most important is clean, cold (below 15 °C), oxygen rich water. Young fish in Simuna Ivax farm weighted 1 g after 160 days that is however 100 days more than Johnston (2002) experience. The causes of young fish slow growth and roe’s high fatality rate in first experiments could be the early state technology and young randomly selected brood fishes with low quality. Also the effect of inbreeding to roe’s survival and young fish vitality cannot be excluded. Roe’s survival during the incubation could be better in case of more consistent surveillance over water parameters and less disturbance.
Kirjeldus
Märksõnad
kalakasvatus, Arktika paalia (Salvenius alpinus), kasvukeskkond, terviseprobleemid, magistritööd