Reproduction, Food, Length -Weight Relationship and Condition Factor of African Catfish Clarias Gariepinus (Burchell) in Lake Babogaya, Ethiopia
| dc.contributor.advisor | Admassu, Demeke (PhD) | |
| dc.contributor.author | Abera, Lemma | |
| dc.date.accessioned | 2018-07-03T11:08:14Z | |
| dc.date.accessioned | 2023-11-08T16:32:43Z | |
| dc.date.available | 2018-07-03T11:08:14Z | |
| dc.date.available | 2023-11-08T16:32:43Z | |
| dc.date.issued | 2007-06 | |
| dc.description.abstract | Some aspects of reproduction, food and feeding habits as well as length weight relationship and condition of Clarias gariepinus in Lake Babogaya were studied at Lake Babogaya located in the vicinity of Bishoftu town at about 45 Km East of Addis Ababa. Samples of C.gariepinus were collected monthly during September (2005) through to August (2006) using hook - and - line method and gillnets of various mesh sizes. Sex ratio was not significantly different from 1:1 except in samples taken in April and July, and in length groups between 25 and 54 cm total length (TL) in the total sample. In all these cases, there was a preponderance of females over males. In the total sample, for instance, females were about 1.26 more numerous than males. The 50% sexual maturity length (L50) was estimated at 50 cm TL for females and 56 cm TL for males. Estimated fecundity, which was linearly related with fish and gonad sizes ranged from 398 to 1165 eggs per gram with a mean of 945. Absolute fecundity was estimated to range from 11,000 to 580,571 with a mean of 159,660. Gonadosomatic index and frequency of ripe gonads suggested that C. gariepinus in Babogaya breeds throughout the year with intensive breeding activity during March to July and less intensively in September. Intensive breeding was coincident with the rainy seasons. C. gariepinus was found to ingest a variety of organisms of plant and animal origins, as well as items including detritus and sand grains. However, insects, zooplankton and fish (Oreochromis niloticus) were found to be the most important food of C. gariepinus in Babogaya. Thus, the fish is considered to have a mainly carnivorous feeding habit. The major food items ingested were all size groups of the fish during all sampling months of the study. However, the importance of insects and zooplankton tended to decrease whereas that of fish tended to increase with the TL of C. gariepinus. Thus, it appeared that the fish feeds progressively more O. niloticus as it grows larger. However, based on predator to prey size ratio of which 85 % range between 1:5 to 1:30, there was no direct correlation between the size of C. gariepinus (predator) and that of its prey (O. niloticus). High incidence of empty stomachs was observed during the whole sampling period. But, the frequency of empty stomach was high during the rainy season, which could be associated with breeding activity. The contribution of insects and zooplankton to the diet of C. gariepinus was relatively highest towards the end of the main rainy season, whereas the contribution of O. niloticus was relatively high during the rainy season. The relationship between total length (25 to 102 cm) and total weight (165 to 7000 g) was curvilinear and represented as TW = 0.0156 TL2.934, R2 = 0.942, P < 0.05. Fulton condition factor (mean ± SE) was 0.66 ± 0.04 for females, 0.63± 0.03 for males and 0.64 ± 0.01 combined for both sexes. Key Words/Phrases: Lake Babogaya, C. gariepinus, Reproduction, Food, length weight relation, condition factor, Ethiopia | en_US |
| dc.identifier.uri | http://etd.aau.edu.et/handle/123456789/5888 | |
| dc.language.iso | en | en_US |
| dc.publisher | Addis Ababa University | en_US |
| dc.subject | Lake Babogaya | en_US |
| dc.subject | C. gariepinus | en_US |
| dc.subject | Reproduction | en_US |
| dc.subject | Food | en_US |
| dc.subject | length weight relation | en_US |
| dc.subject | condition factor | en_US |
| dc.subject | Ethiopia | en_US |
| dc.title | Reproduction, Food, Length -Weight Relationship and Condition Factor of African Catfish Clarias Gariepinus (Burchell) in Lake Babogaya, Ethiopia | en_US |
| dc.type | Thesis | en_US |