Full Text Available
Note: Clicking the button above will open the full text document at the original institutional repository in a new window.
Determination of salinity tolerance limits of tilapia, Oreochromis mossambicus, for use in tuna line fishery
Assignment (MPhil)--Stellenbosch University, 2003.
Saved in:
| Main Author: | |
|---|---|
| Other Authors: | |
| Format: | Thesis |
| Language: | en_ZA |
| Published: |
Stellenbosch : Stellenbosch University
2012
|
| Subjects: | |
| Tags: |
No Tags, Be the first to tag this record!
|
| _version_ | 1867613840819093504 |
|---|---|
| access_status_str | Open Access |
| author | Fitwi, Biniam Samuel |
| author2 | Brink, Danie |
| author_browse | Brink, Danie Fitwi, Biniam Samuel |
| author_facet | Brink, Danie Fitwi, Biniam Samuel |
| author_sort | Fitwi, Biniam Samuel |
| collection | Thesis |
| dc_rights_str_mv | Stellenbosch University |
| description | Assignment (MPhil)--Stellenbosch University, 2003. |
| format | Thesis |
| id | oai:scholar.sun.ac.za:10019.1/53355 |
| institution | Stellenbosch University (South Africa) |
| language | en_ZA |
| last_indexed | 2026-06-10T12:42:31.964Z |
| license_str | Other — see source repository |
| provenance_str_mv | Harvested via OAI-PMH from SUNScholar — Stellenbosch University Repository |
| publishDate | 2012 |
| publishDateRange | 2012 |
| publishDateSort | 2012 |
| publisher | Stellenbosch : Stellenbosch University |
| publisherStr | Stellenbosch : Stellenbosch University |
| record_format | dspace |
| source_str | SUNScholar — Stellenbosch University Repository |
| spelling | oai:scholar.sun.ac.za:10019.1/53355 Determination of salinity tolerance limits of tilapia, Oreochromis mossambicus, for use in tuna line fishery Fitwi, Biniam Samuel Brink, Danie Stellenbosch University. Faculty of AgriSciences. Dept. of Animal Science. Mozambique tilapia -- Effect of salt on Baitfish Osmoregulation Tuna fishing Dissertations -- Agriculture Theses -- Agriculture Assignment (MPhil)--Stellenbosch University, 2003. ENGLISH ABSTRACT: Many species of tilapia such as Oreochromis mossambicus are euryhaline, able to adapt to different salinity waters. Their ability to withstand high salinity levels has given rise to the possibility of using tilapia as baitfish for tuna line fishery. The purpose of the study was to determine the survival rate of tilapia O. mossambicus during direct transfer from freshwater to the salinity levels of 0, 15, 20, 22.5, 25, 27.5, 30, 32.5, and 35 ppt. The data was analysed through means of univariate ANOVAand regression analysis. O. mossambicus showed no mortality to all salinity regimes up to 25 ppt. Mortality was observed at 27.5 ppt, with 100% mortality at 35 ppt. LC 50 and LC 90 were found to be 30.5 and 34.2 ppt, respectively. The results indicate that tilapia (0. mossambicus) will survive a direct transfer to salinities up to 25 ppt. acclimation will be required in the event of transfer to salinity levels above 25 ppt, in order to prevent significant levels of mortalities. AFRIKAANSE OPSOMMING: Meeste van die tilapia spesies soos Oreochremis mossambicus het die vermoë om by water van verskillende soutgehaltes aantepas. Dit is hierdie vermoë om hoë sout vlakke te weerstaan wat die moontlikheid vir gebruik as lewende aas in die tuna langlyn visvangbedryf moontlik maak. Die doel van hierdie studie was om die oorlewingsvlak van tilapia, O. mossambicus te bepaal by die oorplasing van varswater direk na soutwater by vlakke van 0, 15, 20, 22.5, 25, 27.5, 30, 32.5, en 35 dele per duisend. Die data is verwerk deur gebruik te maak van eenvariant ANOVAen regressie analises. O. mossambicus het geen mortaliteite tot gevolg gehad by al die oorplasings van vlakke tot en met 25 dele per duisend sout nie. Mortaliteite is wel gevind vanaf 27.5 dele per duisend, met 100 % mortaliteite by 35 dele per duisend. LC 50 en LC90 was gewees 30.5 en 34.2 dele per duisend onderskeidelik. Die resultate toon aan dat tilapia (0. mossambicus) sal oorleef by direkte oorplasing na soutwater by vlakke van tot en met 25 dele per duisend. Tilapia wat na hoër vlakke as 25 dele per duisend oorgeplaas wil word, sal eers geleidelik moet akklimatiseer om mortaliteite te beperk. Masters 2012-08-27T11:35:26Z 2012-08-27T11:35:26Z 2003-12 Thesis http://hdl.handle.net/10019.1/53355 en_ZA Stellenbosch University viii, 38 p. : ill. application/pdf Stellenbosch : Stellenbosch University |
| spellingShingle | Mozambique tilapia -- Effect of salt on Baitfish Osmoregulation Tuna fishing Dissertations -- Agriculture Theses -- Agriculture Fitwi, Biniam Samuel Determination of salinity tolerance limits of tilapia, Oreochromis mossambicus, for use in tuna line fishery |
| title | Determination of salinity tolerance limits of tilapia, Oreochromis mossambicus, for use in tuna line fishery |
| title_full | Determination of salinity tolerance limits of tilapia, Oreochromis mossambicus, for use in tuna line fishery |
| title_fullStr | Determination of salinity tolerance limits of tilapia, Oreochromis mossambicus, for use in tuna line fishery |
| title_full_unstemmed | Determination of salinity tolerance limits of tilapia, Oreochromis mossambicus, for use in tuna line fishery |
| title_short | Determination of salinity tolerance limits of tilapia, Oreochromis mossambicus, for use in tuna line fishery |
| title_sort | determination of salinity tolerance limits of tilapia oreochromis mossambicus for use in tuna line fishery |
| topic | Mozambique tilapia -- Effect of salt on Baitfish Osmoregulation Tuna fishing Dissertations -- Agriculture Theses -- Agriculture |
| url | http://hdl.handle.net/10019.1/53355 |
| work_keys_str_mv | AT fitwibiniamsamuel determinationofsalinitytolerancelimitsoftilapiaoreochromismossambicusforuseintunalinefishery |