The effects of different diets and stocking density on the growth performance of abeochromis variabilis (Boulenger, 1906) under aquaculture conditions.
| dc.contributor.author | Shoko, Amon Paul | |
| dc.date.accessioned | 2019-07-05T05:14:38Z | |
| dc.date.accessioned | 2020-01-07T15:44:34Z | |
| dc.date.available | 2019-07-05T05:14:38Z | |
| dc.date.available | 2020-01-07T15:44:34Z | |
| dc.date.issued | 2002 | |
| dc.description | Available in print form | en_US |
| dc.description.abstract | The effects of different diets and stocking density on the growth performance of Oreochromis variabilis (L.) (Osteichthyes: Cichlidae) fry were investigated in a hatchery. The diets and stocking density experiments were conducted in a modified 1000-litre circular polytex tanks and 20-litre plastic buckets respectively. O. variabilis fry in the diets experiment were fed on different experimental diets while those reared on stocking density experiment were fed on 'dagaa' fishmeal ad-libitum for 84 and 56 days respectively. The diet that contained cotton seed cake as the main ingredient showed better growth performance than the soyabean meal and composite diet. Fishmeal control diet showed no significant difference (p>0.05) in growth rate over cotton seed cake. Overall mean survival rate for all experiments was 89 ± 1.74% and was not influenced by diets. The conclusion generally reached was that diets containing cotton seed cake could be used to replace fishmeal in feeding O. variabilis. In both small and large size grades of O. variabilis fry cumulative weights increased with increasing stocking density. Lower stocking densities (1 fish fry per litre] showed higher specific growth rate (SGR), Apparent protein efficiency ratio (APER), Apparent food conversion efficiency (AFCE) and better Apparent food conversion ratio (AFCR) than medium (2 fish fry per litre) and high stocking densities (3 fish fry per litre). Overall mean mortality in the size graded stocking experiment was 10 ± 1.47% and 11 ± 1.57% for large and small grades respectively. High and low stocking densities gave highest yield per unit fry tank and better individual fish growth respectively. It is recommended that the choice of stocking density is essentially a trade-off between maximum growth, optimal biomass gain and economic considerations, which may dictate densities that result into a net reduction in overall production costs. | en_US |
| dc.identifier.citation | Shoko, A. P. (2002). The effects of different diets and stocking density on the growth performance of abeochromis variabilis (Boulenger, 1906) under aquaculture conditions. Masters dissertation, University of Dar es Salaam. Available at (http://41.86.178.3/internetserver3.1.2/search.aspx?formtype=advanced) | en_US |
| dc.identifier.uri | http://localhost:8080/xmlui/handle/123456789/1356 | |
| dc.language.iso | en | en_US |
| dc.publisher | University of Dar es Salaam | en_US |
| dc.subject | Microbial growth | en_US |
| dc.subject | Effects of diets and stocking density | en_US |
| dc.subject | Aquaculture conditions | en_US |
| dc.subject | Oreochromis variabilis | en_US |
| dc.title | The effects of different diets and stocking density on the growth performance of abeochromis variabilis (Boulenger, 1906) under aquaculture conditions. | en_US |
| dc.type | Thesis | en_US |