ISSN 2375-0715
Research Article
African Journal of Fisheries Science ISSN 2375-0715 Vol. 7 (1), pp. 001-006, January, 2019. © International Scholars Journals
Full Length Research Paper
Digestibility coefficients of processed jackbean meal Cannavalia ensiformis (L.) DC for Nile tilapia, Oreochromis niloticus (Linnaeus, 1758) diets
Jimoh W. A.1*, Fagbenro O. A.2 and Adeparusi E. O.2
1Fisheries and Aquaculture Unit, Department of Biological Sciences, Crescent University, Abeokuta, Ogun State, Nigeria.
2Department of Fisheries and Aquaculture Technology, Federal University of Technology, Akure, Ondo State, Nigeria.
Accepted 5 October, 2018
Abstract
A study was conducted to determine in-vivo apparent digestibility coefficient of nutrients in processed jackbean meal. Acid Insoluble Ash (AIA) was used as an indicator. The test diets consist of the seed meal replacing soybean meal at 10, 20, 30 and 40% to serve as test diets D10, D20, D30, and D40 respectively. A diet called as diet CTR, without jackbean meal served as control. These diets were fed to Tilapia Oreochromis niloticus fingerlings (6.37 ± 0.07 g) in a glass tanks for 5 weeks. Faecal collection was made by siphoning after four hours of each feeding. Proximate analysis of both diets and faecal samples were carried out for crude protein, lipid, crude fiber, energy, and AIA. These were used to calculate the digestibility coefficient of nutrients. There was no significant difference (p > 0.05) in lipid and organic matter digestibility of the fish fed control diet and test diets. Significant (p < 0.05) variations occurred in nitrogen-free extracts, protein and crude fiber digestibility of fish fed control diet and the test diets.
Key words: Digestibility, in vivo, jackbean, Oreochromis niloticus.
Jimoh W. A*, Fagbenro O. A. and Adeparusi E. O.
Page: 1 - 6
https://doi.org/10.46882/AJFS/1059Research Article
African Journal of Fisheries Science ISSN 2375-0715 Vol. 7 (1), pp. 001-009, January, 2019. © International Scholars Journals
Full Length Research Paper
Recruitment patterns and standing stocks of the beaked clam Eumarcia paupercula (Holten, 1802) in Maputo Bay, Mozambique
13E. D. Mugabe, 12C. A. Amoda, 3C.L. Griffiths
1Centre of Coastal Studies and School of Marine and Coastal Sciences, Eduardo Mondlane University, Chuabo Dembe, P.O. Box 128, Quelimane, Mozambique.
2National Institute of Fisheries Research, Av. Mao Tsé Tung 4603, Maputo, Mozambique.
3Marine Biology Research Institute and Department of Biological Sciences, University of Cape Town, Rondebosch 7701, South Africa.
Corresponding author E-mail: [email protected]
Accepted 24 October, 2018
Abstract
The beaked clam Eumarcia paupercula is abundant in Maputo Bay, where it forms the basis of a substantial artisanal fishery. This study aimed to understand the recruitment pattern of the E. paupercula population of Costa do Sol beach and to monitor seasonal changes in its standing stocks and how these are impacted by the fishery. Results from November 2012 – April 2014 sampling programme showed that recruitment took place throughout the year, with the highest recruitment rates occurring during early winter, with over 250 recruits.m-2 and lowest in late winter and early summer, with less than 20 recruits.m-2. The abundance of the adult stock seemed to have little influence on recruitment rates. The total standing stock of E. paupercula across the approximately 144 000 m2 study site at Costa do Sol beach varied from a minimum of 7 238 kg in May to a maximum of 54 164 kg in November with a mean of approximately 25 300 kg. Seasonal changes in standing stock were controlled mainly by patterns of recruitment and of removal of adult clams by the artisanal fishery.
Keywords: Stock-recruit relationship, length frequency, Veneridae, bivalve fishery, tidal flat.
Mugabe E. D, Amoda C. A and Griffiths C.L
Page: 1 - 9
https://doi.org/10.46882/AJFS/1058Research Article
African Journal of Fisheries Science ISSN 2375-0715 Vol. 7 (1), pp. 001-005, January, 2019. © International Scholars Journals
Full Length Research Paper
A karyological analysis of PUNTIUS CONCHONIUS (Hamilton, 1822) (Pisces, Cyprinidae), a new cytotype from Dal Lake Srinagar Kashmir, J&K, India
Farooq A. Ganai* and A. R. Yousuf
Limnology and Fisheries Laboratory, Centre of Research for Development, University of Kashmir, Hazratbal Srinagar-190 006, India.
Accepted 2 May, 2018
Abstract
The karyotypic and cytological characteristics of Rosy barb, PUNTIUS CONCHONIUS (Hamilton, 1822) (cyprinidae) were investigated by examining metaphase chromosomes spreads from the anterior kidney following Thorgaard and Disney (1990). The fishes were obtained from the local fishermen and transported live to the Limnology and Fisheries Laboratory of Centre of Research for Development, University of Kashmir. Ten fish were injected intraperitoneally with two doses of phytohemagglutinin (PHA), 4 µg g-1body weight with a 20 h interval to induce cell division. After 8 h in 20°C water, the fish were injected intraperitoneally with colchicine 0.05% @ 0.5 ml/50 g body weight to depress the cell division in the metaphase stage and left for 2 to 3 h before sacrificing. Kidney and gill epithelia were used for karyotype analysis. The diploid chromosome number of the fish was 2n = 50, consisting of 11 pairs of metacentric, 8 pairs of submetacentric and 6 pairs of telocentric chromosomes respectively. Centromeric index, arm ratio and Fundamental Number were determined as 0 to 50, 1-∞ and 88 respectively. No heteromorphic sex chromosomes were cytologically detected.
Key words: Chromosome, Puntius conchonius, Dal Lake, karyotype.
Saeed Hajirezaee and Zahra Ajdari, Daniel Ajdari*
Page: 1 - 5
https://doi.org/10.46882/AJFS/1057Research Article
African Journal of Fisheries Science ISSN 2375-0715 Vol. 7 (1), pp. 001-009, January, 2019. © International Scholars Journals
Full Length Research Paper
Fish colonization of artificial reefs in the Persian Gulf (Bandar Lengeh-Iran): Reef designs and seasonal changes of fish abundance
Daniel Ajdari*, Saeed Hajirezaee and Zahra Ajdari
Department of Biology and Stock Assessment, Offshore Fisheries Research Center, Chabahar, Iran.
Accepted 24 August, 2018
Abstract
Artificial reefs are used as a management tool to compensate for overfishing and anthropogenic degradation. In the present study, to find the best artificial structure for enhancing of fish yields, the values of total fish catch and its seasonal changes were investigated in different forms of artificial structures placed in costal waters of Persian Gulf (Bandar-e-Lengeh-Iran). For this purpose, eight treatments including different forms of artificial reefs, reef ball (RB), fish house (FH), non-designed materials (ND), RB+FH, RB+ND, FH+ND and RB+ND+FH and one control group (C) were established. At each site, the fish sampling were carried out every three months for one year. According to data, total fish catch was higher significantly in RB+ND+FH treatment than in other experimental reef structures. As well as, the total fish yields in spring season were significantly higher than in other seasons. The catch composition data showed that Epinephelus coioides with 65% allocates the main quota of total catch on experimental artificial structures. In conclusion, the results indicated that artificial structures especially a complex of RB+ND+FH are more suitable for enhancing of fish catch successes in inshore waters of Bandar Lengeh.
Key words: Artificial reefs, reef ball, Persian Gulf.
Daniel Ajdari*, Saeed Hajirezaee and Zahra Ajdari
Page: 1 - 9
https://doi.org/10.46882/AJFS/1056Research Article
African Journal of Fisheries Science ISSN 2375-0715 Vol. 7 (1), pp. 001-006, January, 2019. © International Scholars Journals
Full Length Research Paper
Parasites of landed fish from Great Kwa River, Calabar, Cross River State, Nigeria
Ekanem A. P.1*, Eyo V. O.1 and Sampson A. F.2
1Department of Fisheries and Aquaculture, University of Calabar, Nigeria.
2Department of Marine Biology, University of Calabar, Nigeria.
Accepted 21 October, 2018
Abstract
Parasites of landed fish from the Great Kwa River, Calabar, Cross River State, Nigeria were studied. Parasitological examination of 180 fish samples belonging to 9 taxa from the River showed 50% incidence for Chrysicthys nigrodigitatus, 16.67% for Heterotis noloticus, Clarias gariepinus and Tilapia galileaus respectively and 0% for Hepsetus odoe, Arius gigas, Momyrus rume, Ethmalosa fimbriata and Cynoglossus senegalensis. Parasite infestations were found in the stomach and intestine, and no parasites were found on the fins, skin and gills. Nematodes, cestodes and protozoan were found in decreasing order of abundance. Diphyllobothrium sp. was found in the intestine of C. nigrodigitatus; Camallanus sp. was found in the intestine of H. niloticus and T. galileaus while protozoan cysts were found in the intestine of C. garipinus. Parasites were more prevalent in the fish of 30 to 39.9 cm total length size range. The study determined that in the Great Kwa River the preferred organs of parasites were the intestines and stomach.
Key words: Parasites, landed fish, Great Kwa River.
Eyo V. O and Sampson A. F, Ekanem A. P*
Page: 1 - 6
https://doi.org/10.46882/AJFS/1055Research Article
African Journal of Fisheries Science ISSN 2375-0715 Vol. 6 (8), pp. 001-015, August, 2018. © International Scholars Journals
Full Length Research Paper
Histopathology of Nile Tilapia (Oreochromis niloticus) juveniles exposed to aqueous and ethanolic extracts of Ipomoea aquatica leaf
Ayoola Simeon Oluwatoyin
Department of Marine Sciences, University of Lagos, Akoka, Yaba, Lagos State, Nigeria. E-mail: [email protected], [email protected]. Tel: +234(80)34650102.
Accepted 17 March, 2018
Abstract
The effect of aqueous and ethanolic extracts of Ipomoea aquatica leaf on the histopathology of selected organs of the fresh water Oreochromis niloticus was investigated. The differential acute toxicity of aqueous and ethanolic extracts of I. aquatica leaf on Nile Tilapia, O. niloticus were carried out under laboratory conditions. The LC50 after 96 h of exposure for aqueous and ethanolic extracts of Ipomoea aquatica were 2.659 and 0.196 g/L, respectively. These values showed that ethanolic extract of I. aquatica was more toxic than its aqueous extract. Signs of agitated behaviours, respiratory distress and abnormal nervous behaviours including eventual deaths were observed in exposed fish. Control fish neither died nor exhibited any unusual behaviour. Histopathological changes of gill, liver and muscle were noticed when O. niloticus was exposed to aqueous extract of I. aquatica for 96 h. In the gills, filament cell showed lesion, necrosis, malignancy, cellular degeneration and inflammation. In the liver, there was vacuolation of hepatocytes, inflammation and necrosis. In the muscle there was mild lesion, necrosis, inclusion bodies, inflammation and cellular degenerations. Similar result was obtained when the tested organism (O. niloticus) was exposed to ethanolic extract of I. aquatica for the same duration and under the same laboratory conditions. But the level of tissue and organ degeneration is more severe in the case of the ethanolic extract than in aqueous extract. This investigation revealed that leaf of I. aquatica has piscicidal property and can be put into use in the control and management of fish ponds by farmers. Therefore, this plant can actually be use as a biological control in eradicating predators and unwanted organisms in the ponds by farmer instead of using agrochemicals.
Key words: Histopathology, Ipomoea aquatica, Oreochromis niloticus.
Ayoola Simeon Oluwatoyin
Page: 1 - 15
https://doi.org/10.46882/AJFS/1052