ISSN 2375-0715
Research Article
African Journal of Fisheries Science ISSN 2375-0715 Vol. 6 (7), pp. 001-008, July, 2018. © International Scholars Journals
Full Length Research Paper
Morphometric measurements and growth patterns of four species of the genus Synodontis (cuvier,1816) from Lower Benue River, Makurdi, Nigeria
Akombo P. M., Atile J. I., Adikwu I. A. and Araoye P. A.*
Department of Biological Sciences, Benue State University, Makurdi, Nigeria.
Accepted 3 of March, 2018
Abstract
Relationship between basic morphometric measurements and growth pattern of four species of Synodontis from Lower Benue River was investigated bi-monthly from February to October, 2009 to determine variations and differences in the growth pattern of the different populations. Morphometric parameters of a total number of 195 specimens of Synodontis clarias, Synodontis membranaceus, Synodontis resupinatus and Synodontis schall were measured and evaluated by linear regression and correlation. There was a strong positive correlation between body weight and body girth, standard length and body weight, standard length and head length, standard length and body depth, standard length and snout length, standard length and eye diameter and body weight and eye diameter in S. clarias, S. membranaceus, S. resupinatus, and S. schall but the correlation between standard length and eye diameter and body weight and eye diameter in S. resupinatus were low. The growth pattern analysis depicts allometric growth in these species with their ‘b’ values less than 3.
Key words: Synodontis, morphometric, Lower Benue River.
Adikwu I. A. and Araoye P. A.*, Akombo P. M., Atile J. I.
Page: 1 - 8
https://doi.org/10.46882/AJFS/1051Research Article
African Journal of Fisheries Science ISSN 2375-0715 Vol. 6 (6), pp. 001-008, June, 2018. © International Scholars Journals
Full Length Research Paper
Profitability analysis of small scale aquaculture enterprises in Central Uganda
Theodora S. Hyuha1*, James O. Bukenya2, Julius Twinamasiko1 and Joseph Molnar4
1Department of Agribusiness and Natural Resources, Faculty of Agricultural Sciences, Makerere, University, Kampala, Uganda.
2Department of Finance, Agribusiness and Economics, Alabama A&M University, Normal, Alabama, USA.
4Office of International Agriculture, Auburn University, Auburn Alabama, USA.
Accepted 19 January, 2018
Abstract
The study had three overriding objectives. Firstly, to assess the profitability of small-scale aquaculture production enterprises in central Uganda; secondly, to ascertain the factors affecting profitability; and thirdly, to identify the constraints to fish farming in the region.The data were collected through a survey questionnaire administered to a random sample of 200 small scale fish farmers in the three major fish farming districts of Mpigi, Mukono and Wakiso in central Uganda. The analysis was carried out using descriptive statistics, enterprise budgeting and ordinary linear regression. Although the results show small-scale aquaculture enterprises to be profitable in the study region, the estimated profit margins are relatively small. Farming experience, fish price, record keeping, feed cost and volume of fish harvested were the most influential factors in explaining profitability. The key factors identified as hindrances to aquaculture development in the region included predators, unavailability of credit facilities, expensive feeds, shortage and poor quality of fingerlings.
Key words: Aquaculture, enterprise budgets, profitability, Uganda, small farmers.
James O. Bukenya, Theodora S. Hyuha*, Julius Twinamasiko and Joseph Molnar
Page: 1 - 8
https://doi.org/10.46882/AJFS/1050Research Article
African Journal of Fisheries Science ISSN 2375-0715 Vol. 6 (5), pp. 001-009, May, 2018. © International Scholars Journals
Full Length Research Paper
Effects of dietary lipid sources on reproductive performance, egg and larval quality and egg fatty acid composition
S. Sangsawangchote1, N. Chaitanawisuti2* and S. Piyatiratitivorakul1
1Department of Marine Science, Faculty of Science, Chulalongkorn University, Phya Thai Road, Bangkok, Thailand.
2Aquatic Resources Research Institute, Chulalongkorn University, Phya Thai Road, Bangkok, Thailand.
Accepted 19 October 2017
Abstract
A 120 day feeding trial was conducted to evaluate the reproductive performance, egg and larval quality and egg fatty acid composition in Spotted Babylon (Babylonia areolata) broodstock fed with natural food (fresh meat of carangid fish, Seleroides leptolepis,) and one of four experimental formulated diets containing 5 or 15% of dietary lipid from either tuna oil or a mixture of tuna oil and soybean oil (6:4) labeled as 5% TO, 15% TO, 5% MO and 15% MO respectively. Using trash fish as a control food resulted is the lowest levels of in 20:5 n - 3, 22:6 n - 3 and 20:4 n - 6 fatty acids compared to those of all experimental diets, while the highest contents of those fatty acids were found in the 5% TO diet. Statistically significant differences in reproductive performance between dietary treatments with the best reproductive performance were found only for females fed the 5% TO diets, but egg and larval quality showed no variability among females fed trash fish and all experimental diets. No significant differences were observed in the survival duration in the starvation tolerance test for females fed trash fish or any of the experimental diets. However, the fatty acid profile of egg capsules was significantly affected by the dietary treatments. The levels of major fatty acids (20:5 n - 3, 22:6 n - 3 and 20:4 n - 6) in egg capsules produced from females fed diets containing 5% tuna oil (5% TO) was significantly higher than those from females fed trash fish or other experimental diets. We therefore conclude that formulated diets resulted in successful reproduction and high essential fatty acids in egg capsules comparable to the use of trash fish.
Key words: Babylonia areolata, broodstock diet, reproductive performance, egg and larvae quality.
N. Chaitanawisuti* and S. Piyatiratitivorakul, S. Sangsawangchote
Page: 1 - 9
https://doi.org/10.46882/AJFS/1049Research Article
African Journal of Fisheries Science ISSN 2375-0715 Vol. 6 (4), pp. 001-005, April, 2018. © International Scholars Journals
Full Length Research Paper
Real-time quantitative (PCR) applications to quantify and the expression profiles of heat shock protein (HSP70) genes in Nile tilapia, Oreochromis niloticus (L.) and Oreochromis mossambicus (P.)
J. Baby Joseph and S. S. Sujatha*
International Centre for Bioresource Management, Malankara Catholic College, Mariagiri, Kaliakkavilai, 629153, Kanyakumari District, TamilNadu, India.
Accepted 28 January, 2018
Abstract
Quantitative real-time PCR (qRT-PCR) has already been used to study the expression profiles of heat shock protein (Hsp) genes in Nile tilapia, Oreochromis niloticus (Lineaus, 1752) and Oreochromis mossambicu (Peter, 1983). Young fish were exposed to heat stress for 5.5 h followed by qRT-PCR of Hsp70 mRNA, using tubulin (tub) as a reference gene and flourogenic dyes. Expression of Hsp70 mRNA peaked at 1 h of heat stress and decreased at 5.5 h. This method proved to be a very sensitive technique in quantifying Hsp70 transcripts in 6.70 ng of total DNA from the two tilapia species. A standard curve was prepared, for both tilapia fishes showed almost uniform results throughout the experiment. The threshold PCR cycle (Ct), at which RT -PCR products from DNA standards accumulated to a critical level, was determined for samples in the range of 2 × 104 to 2 × 1010 molecules/ l. From conclusion of this study, it is shown that when the tilapia fish muscles are subjected to stress, with the help of abiotic factors- temperatures, whether above or below optimum condition within a stipulated period of time in a peculiar way, will lead to the production of the Hsp70 protein.
Keywords: Hsp70, quantitative RT-PCR, Oreochromis mossambicus, Oreochromis niloticus.
J. Baby Joseph, S. S. Sujatha*
Page: 1 - 5
https://doi.org/10.46882/AJFS/1048Research Article
African Journal of Fisheries Science ISSN 2375-0715 Vol. 6 (4), pp. 001-007, April, 2018. © International Scholars Journals
Full Length Research Paper
Optimum dietary protein levels and protein to energy ratios on growth and survival of juveniles spotted Babylon (Babylonia areolata Link) under the recirculating seawater conditions
N. Chaitanawisuti1*, C. Rodruang2 and S. piyatiratitivorakul2
1Aquatic Resources Research Institute, Chulalongkorn University, Phya Thai Road, Bangkok, Thailand 10330.
2Department of Marine Science, Faculty of Science, Chulalongkorn University, Phya Thai Road, Bangkok, Thailand 10330.
Accepted 5 January, 2011
Abstract
A feeding experiment of three dietary protein levels (35, 40 and 45%) and three dietary energy levels (3.8, 4.0 and 4.2 kcal g-1 diet) factorial design with four replicates was conducted to determine the proper dietary protein and energy levels for the growth and survival of the juveniles spotted Babylon Babylonia areolata under the recirculating seawater conditions. Snails with initial body weight averaging 0.29 ± 0.01 g were fed the experimental diets for 16 weeks. Survival rates (SR) of each group was above 95% and no significant difference among dietary treatments (p > 0.05). Mean weight gain of snails fed the 35% protein diets with 4.0 kcal/g diet was significantly (P < 0.05) different from that of snails fed the 40 and 45% protein diets at all energy levels. Feed conversion ratio (FCR) was significantly influenced by dietary protein and energy levels (p < 0.05). Diets containing 35% protein level and 4.0 kcal g-1 energy level appeared to be utilized more efficiently in term of FCR (3.21) than diets containing the other dietary protein and energy levels, ranging 3.62 - 4.54. The results of this study indicate that a diet containing 35% dietary protein and 4.0 kcal g-1 diets with P/E ratio of 85.99 mg protein/kcal was recommended for juvenile B. areolata growth under our experimental recirculating seawater conditions.
Key words: B. areolata, dietary protein, protein / energy ratio, growth, survival.
C. Rodruang and S. piyatiratitivorakul, N. Chaitanawisuti*
Page: 1 - 7
https://doi.org/10.46882/AJFS/1047Research Article
African Journal of Fisheries Science ISSN 2375-0715 Vol. 6 (2), pp. 001-006, February, 2018. © International Scholars Journals
Full Length Research Paper
Site selection for grouper mariculture in Indonesia
W. Brian Szuster1* and Hatim Albasri2
1Department of Geography, University of Hawai‘i at Mānoa Saunders 445, 2424 Maile Way Honolulu, Hawai‘i, USA 96821.
2Research Center for Indonesian Aquaculture, Indonesian Ministry of Marine Affairs and Fisheries, Jakarta, Indonesia.
Accepted 09 November, 2017
Abstract
This research assesses a site selection approach for net-cage grouper mariculture off Kaledupa Island in Indonesia. Data collection focused on 15 biophysical site capability parameters, plus an additional 7 site suitability parameters assessed through interviews with villagers and local experts. Site capability analysis identified 4,511 ha capable of sustaining grouper mariculture within the 8,582 ha study area. Suitability analysis identified 2,667 suitable ha based on villager opinions and 4,083 suitable ha based on local expert opinions. Reliance on villager opinions and resolution of fragmentation issues reduced the final area deemed suitable to 2,423 ha.
Key words: Grouper, siting, mariculture, Kaledupa Island.
W. Brian Szuster*, Hatim Albasri
Page: 1 - 6
https://doi.org/10.46882/AJFS/1044