Ngaphambi kokufuya iimfesi ngokusebenzisa amanzi afretjhi, kuqakathekile ukuba nemano werhwebo ehle, khetha abathengi bakho ozobathengisela iimfesi, thola amanzi wekhwalithi, iinsiza ezifaneleko, istoko seemfesi ezinepilo ehle namakghono afaneleko wokufuya iimfesi ngokusebenzisa amanzi afretjhi.
Khuyini I-Tilapia?
I-Tilapia ingeyesibili esibalweni somhlobo weemfesi ezifuywako ephasini. Ngokuvela zivela e-trophika ye-Afrika neduze neMpumalanga yephasi, i-tilapia kumhlobo weemfesi odla iintjalo nenyama yenye iinlwane begodu ikghona ukuphila endaweni ezinobujamo obahlukahkukeneko botjhiso. Zingafuywa emanzini afuthumele ngamazinga ahlukahlukeneko (20 - 30℃), kodwana ziphila kuhle khulu eenzibeni ezinokudla kwemvelo.
Ngimiphi Imihlobo ye-Tilapia Ehle Engafuywa?
Eminye imikhiqizo ye-tilapia engaba ku 95% ekhiqizwa ephasini isebenzisa ama-Oreochromis niloticus abudisi, i-Nile tilapia. Umhlobo lo udlule i-O. mossambicus (Mozambique tilapia) eyasetjenziswa ngaphambilini eyayibhalelwa kukhula nayiyincani. Ikhula kancani beyibe nokwakheka okuncani komzimba, owawunikela umkhiqio ophasi weemfesi.
Umhlobo we-Nile tilapia aeungenwa malwelwe, zikhula msinya begodu zinomzimba omkhulu (deep bodied) ngizo ezitholakala emarhwebeni, zinombala obovu nosiliva. ("Deep bodied" kutjho bona umzimba omkhulu kunaloyo omncani, onehloko ekulu nenyama encani njenge-O. mossambicus).
Umhlobo we-Nile tilapia ungakhula kusukela ku 1 g ubuncani kufikela ku 500 g (ubukhulu bokuthengiswa) eenyangeni ezi 8-9 nawumadanisa neenyanga ezi 14 zeminye imihlobo ye-tilapia.
I-Nile tilapia ibanjwa khulu e-Sewula Africa kodwana idinga iphemithi ekhethekileko ebuya e- Department of Environmental Affairs (DEA) yeSewula Africa, lapho ethathwa njengomhlobo weemfesi ezivela kwamanye amazwe.
Ubujamo Bokukhulisa I-Tilapia
I-Tilapia kumhlobo weemfesi othanda amanzi afuthumeleko asemazingeni ahlangana na 24 - 32°C. Amazinga i-tilapia ekhula ngayo ayehla lokha amazinga wokutjhisa nakangaphasi kwe 20°C begodu itjengisa ukungakhuli lokha amazinga nakangaphasi kwe 15°C. I-tilapia ithola amagulo lula lokha amazinga wokutjhisa nakangaphasi kwe 15℃ begodu ziyafa amazinga nakangaphasi kwe 12℃. Lokhu kuvimbela iindawo zeSewula Africa lapho umhlobo weemfesi loo ongakhuliselwa khona ngaphandle, nanoma izindlu zama-green house tunnel zenza kube lula ukufuya iimfesi kunanoma ngiyiphi indawo.
Namkhana ama-tilapia akghona ukuphila ngomoya wokuphefumula ophasi (ongaphasi kwe 4 ppm) ne-amoniya esizingeni eliphezulu kunaleyo yomhlobo omunye weemfesi (e.g. trout) azikhulu kuhle lokha amazinga wekhwalithi yamanzi nakangasisemazingeni aphasi ngokwaneleko. Kuliphutha ukukholwa bona i-tilapia ingakhula endaweni enganamazinga amahle.
Iindawo Zokukhiqiza I-Tilapia eSewula Africa
Nanoma amazinga afuthumeleko kungiwo afunekako unyaka woke, iinarha ezikhiqiza inani eliphezulu le-tilapia njenge-Egypt (lapho amathani angaphezulu kwe 750 000 akhiqizwa khona qobe nyaka) kutjengisa bona iindawo zeSewula Africa zifanele ukukhiqiza ama-tilapia. I-Egypt, namazinga wayo afuthumeleko ebusika, inezingalokutjhisa lamanzi elingaphazi kwe 10℃.
Zinengi iindawo eSewula Africa ezise Lowveld (eemfundeni zeLimpopi nezeMpumalanga Incomati corridor) nezesifundeni zetlhagwini yaKwaZulu-Natal ezinamazinga angaphezulu kwe 150℃ ebusika, ekungizo ezinobujamo bomtjhiso obuhle bona kungafuywa kizo ama-talapia.
Ihlelo Le-Green Water Pond Elenzelwe I-Talapia
Indundu yefuyo ye-talapia e-China, Indonesia, e-Phillippines, Bangladesh, Israel ne-Egypt yenziwa ngokuvundisa nokupha ukudla ama-green water ponds.
“Ukuvundisa” ama-green water ponds kukufakelela amakhemikhali wokuvundisa nofana iinlwane emanzini ukuthuthukisa ukukhula kokudla kweemfesi kwemvelo-iinlwane ezifana ne-daphnia, cyclops nama-algaes ekudliwa ziimfesi. Amanzi atjhugulula umbala abehlaza nakwenzeka ikambiso lee.
Ekunikelweni ukudla eenzibeni ezinamanzi ahlaza ngombala, ama-artificial pelletized feeds ayasetjenziswa. Iinziba lezi kufanele kube ngezikulu ukulonda amanzi wekhwalithi ehle, ubukhulu obungalingana ne 0.25 ha (e.g. 50 m x 50 m).
Woke ama-tilapia asesemancani afuywa wodwa nalayo wesilisa abekwa wodwa, ukuvikela ukuminyana eenzibeni. Ihlelo lakade leminyaka yabo 1960s elincani, iinziba zamanzi abonakalako, ukusebenzisa iimfesi ezincani zobulili obuvangiweko nezabezimu abangaziwako yabonakala njengelinganamsebenzi.
Ihlelo le Re-Circulating Elenzelwe Ama-Tilapia
Re-circulating aquaculture systems (RAS) elenzelwe ukufuya umhlobo weemfesi ze-talapia khelazanywa ngaphambilini eendaweni ezisemadorobheni nezisemadorobhaneni. Namkha kunjalo, ihlelo le-RAS litlhoga i-eneji namakghono begodu lisalele emuva ngokudinga i-artificial feeding. E-Sewula Africa, i-tilapia ukudla kwayo kudurile lokha nawukuqathanisa nakamanye amazwe afana neZambia. Nge-food conversion ration (FRC) elingana ne 1:1.5 ngamahlelo amahle, ngokusebenzisa isibonelo ukudla kwe-talapia kwe R12/kg, kungabiza imali engange R18/kg kunanoma kukuphi e-RSA.
I-eneji, amakghono nezinye iindleko zenza bona ukurhweba kungabazeke. Ngokuhlanganisa i-eneji ephezulu nendleko zokubhadela umsebenzi, iindleko zokukhiqiza i-tilapia zidlula imali yokuthenga inyama ye-tilapia emakethe ngezinye iinkhathi.Nanoma iSewula Africa inekghono lokuphatha amanzi wekhwalithi kufanele kwamukelwe bona kunengozi zokobana amahlelo angeze aphumelela kwesinye isikhathi, lokha nakunokulahlekelwa sitoko.
Amahlelo anjalo athembele khulu ku-eneji isikhathi esinengi 24/7, bekadinge namanye amahlelo we-eneji angasentjenziswa lokha nakubhale ihlelo lokuthoma nofana elibekiweko lokunikela i-eneji namazinga aphazelu wekghono lobuthekniki. Ngokungezelela, ayikahlolwa kwezamarhwebo ngalesi sikhathi.
Translated by Busisiwe Skhosana