A goal-oriented researcher with N.C.E., B.Agric., M.Sc. and Ph.D. Dr. R.O. Moruf is an aquatic animal scientist with experience in "Macro-invertebrate Fisheries" which focuses on Shellfish Biology, Eco-Physiology, Toxicology, Genetics, Culture, Nutrition, Processing & Extension/Economics. Supervisors: Associate Professor, Dr. (Mrs). Aderonke O. Lawal-Are (B.Sc, M.Sc, Ph.D. Fisheries)
African Journal of Agriculture, Technology and Environment , 2020
Serum biochemical profile is often applied as an index of physiological condition of invertebrate... more Serum biochemical profile is often applied as an index of physiological condition of invertebrates and thus provide information about the health status of local populations. The study aimed to establish normal ranges for chosen serum biochemical parameters of gastropod species, Pachymelania fusca (Gmelin, 1791) from Ologe and Badagry Lagoons using standard methods. In terms of water quality, Badagry Lagoon showed significant (P < 0.05) higher values in total dissolved solid (88.45 mg/L), chemical oxygen demand (41.88 mg/L), biological oxygen demand (35.73 mg/L), total suspended solid (100.44 mg/L), total hardness (102.06 mg/L), sulphate (34.31 mg/L) and nitrate (1.43 mg/L). In dry season, P. fusca from Ologe Lagoon had higher activities of aspartate aminotransferase (AST) (29.77±1.78 u/l), alanine aminotransferase (ALT) (11.69±1.68 u/l) and alkaline phosphatase (ALP) (140.58±49.64 u/l) than the activities of that from Badagry Lagoon. In wet season, the activity of ALP in P. fusca from Badagry Lagoon ranged from 63.48 to 118.68, and significantly higher than the range of 39.68 to 104.88 in P. fusca from Ologe Lagoon. Total protein was also higher in P. fusca from Badagry Lagoon, ranging from 10.77 to 42.46 g/L. The haemolymph activity of P. fusca from both studied locations varied across season
Moringa oleifera has impressive range of nutritional and medicinal values which when consumed hav... more Moringa oleifera has impressive range of nutritional and medicinal values which when consumed have influence on hematological profile which is applied as an index of physiological condition of various organisms and thus provide information about the health status of local populations. The study aimed to determine the effects of M. oleifera aqueous leaves extract on the hematology, serum biochemical profile and antioxidant enzyme activities of the burrowing crab, Cardiosoma guanhumi. Thirty juveniles of C. guanhumi (Average weight 43.20±0.05 g) were tested, where six crabs were randomly selected and distributed per each tank (1 x 1x 0.6m3) of 1litre of water. Different diets containing M. oleifera aqueous extract at inclusion levels of 0.5 ml, 1.0 ml, 1.5 ml, 2.0 ml and control were used to feed the crabs. Total Haemocyte Count ranged between 2733.33±0.90 mL and 6350.00±0.60 mL; there were significant differences among the treatment groups (p < 0.05). Haemocyte sub-population variables showed that crabs fed the control and 2.0ml M. oleifera kg-1 diet had increased in the granulocyte and monocyte populations but a decrease in the agranulocytes. The results of the serum enzymes showed an increase as the level of M. oleifera aqueous extract increases in the diet. Highest superoxide dismutase (75.43 ±21.25 min/mg pro) and catalase activities (2.96±0.18 min/mg pro), malondialdehyde (12.05±2.09 nmol/L) and glutathione concentrations (0.19 ±0.02 μmol/L) were recorded in crabs fed diet T4 (2.0ml M. oleifera kg-1), while the lowest were obtained in crabs fed control diet. The present study showed that the inclusion of M. oleifera aqueous extract up to 1.0ml kg-1 will have immunomodulatory performance on Cardiosoma guanhumi without any deleterious effect on the crab’s health status.
The degree of genetic variation in a population clearly specifies the structure of stocks and the... more The degree of genetic variation in a population clearly specifies the structure of stocks and the probability of sustenance in future. The portunid crab, Callinectes amnicola, is presently managed as a single stock in Nigeria. Hence, genetic heterogeneity in this species from three interconnecting lagoons (Badagry, Lagos and Epe) was analysed using randomly amplified polymorphic DNA technique. The DNA yield and purity across populations ranged from 61.63 to 2983.34 ng/μl and from 1.68 to 1.86 respectively. The six RAPD primers: OPA-04, OPA-05, OPA-09, OPA-11, OPA-17 and OPAB-08 successfully amplified genomic DNA of 30 individual of C. amnicola from 3 populations with 1 region and 999 permutations. 86 RAPD fragments ranging from 96 to 1403 bp in length were generated. With 69 loci, the percentages of polymorphic bands for each primer across all populations were 60.87% (Badagry Lagoon crab), 62.32% (Lagos Harbour crab) and 66.67% (Epe Lagoon crab). Similarity index ranged from 0.848 to 0.893 and genetic distances from 0.114 to 0.165. The variations within and among the crab populations were 78% and 22% respectively. UPGMA Dendogram among C. amnicola populations using Nei’s genetic distance obtained three main clusters, Epe Lagoon, Lagos Harbour and Badagry Lagoon, with seven outliers. The study established a relative geographical heterogeneity and limited gene flow across C. amnicola populations in coastal waters of Lagos, Nigeria.
The Proceedings of the Nigerian Academy of Science, 2020
Sustainable Development Goal 14 aims to increase the protection and sustainable management of coa... more Sustainable Development Goal 14 aims to increase the protection and sustainable management of coastal ecosystems and their resources while addressing threats such as pollution and ocean acidification. Nigeria as a nation with a coastline of approximately 853km facing the Atlantic Ocean is on one hand, at the mercy of the ocean but, on the other hand, the custodian of its resources. These resources like shellfishes sustain us today, and without them future generations will suffer, this is why there is a law against the destructive fishing practices, illegal, unreported and unregulated fishing activities. This article highlights the few priority areas and sustainability challenges for Nigerian shellfish resources as coastal lagoons are fully exploited and increase in harvest of shellfish resources from the lagoons is unlikely. It was noted that despite the availability of regulations, noncompliance by fisher folks has not helped in managing the exploitations. It is therefore recommended that officials need to work with those responsible for social policies, such as employment and other relevant policies, to make sure that the overall government policy direction is coherent and consistent. Also, giving coastal communities access to resources and allowing those access privileges to be traded can help in sustainable management of shellfish resources.
Bulletin UASVM Animal Science and Biotechnologies , 2020
Bivalve mariculture is a type of molluscan farming done in open seawater on racks, rafts or longl... more Bivalve mariculture is a type of molluscan farming done in open seawater on racks, rafts or longlines where naturally occurring phytoplankton serves as a key food item, introduced into the enclosures with the normal circulation of seawater. Increasingly, the reverse trophic interaction is being recognized; dissolved inorganic and organic waste compounds released by metabolically active bivalves can supply phytoplankton with nutrient and energy requirements for their growth. This two-way interaction can be viewed as a type of community symbiosis developed over long evolutionary timescales. The extent to which this affects overall nutrient budgets and thus primary production is related to the system flushing rate and residence time. Here we reviewed the feeding mechanism and nutrient recycling activities of bivalve and also emphasized the role of phytoplankton as a key nutritional live feed in sustainable bivalve mariculture. Bivalves influence nutrient dynamics through direct excretion and indirectly through microbial mediated remineralisation of their organic deposits in the sediments. The quantitative knowledge of bivalve - phytoplankton trophic interactions in coastal waters will inform bivalve mariculture development to effectively serve the needs of both seafood production and ecosystem restoration.
The concentrations of Mn, Cu, Fe, Zn, Hg and Cr were analyzed in the edible part of four species ... more The concentrations of Mn, Cu, Fe, Zn, Hg and Cr were analyzed in the edible part of four species of aquatic molluscs collected in different fish markets in Lagos using standard methods. Assessing the metal levels in periwinkle, oyster, clam and cuttlefish, muscle levels in mg kg-1 of Mn (0.57±0.00), Zn (2.85±0.00) and Cr (0.69±0.01) in clam were significantly higher (p<0.05) than their corresponding values in other examined mollusc species. Lowest mean levels (mg kg −1) of Mn (0.002±0.00), Fe (0.504±0.02) and Cu (0.025±0.00) in oyster, Zn (0.131±0.02) in periwinkle, Hg (0.001±0.00) and Cr (0.004±0.00) in cuttlefish were observed. However, the mean values of Fe, Cu and Hg were not significantly different across samples. The estimated daily intake of heavy metals (mg person-1 day-1) revealed that Mn (0.000001) in oyster and Hg (0.000001) in cuttlefish contributed the lowest daily intake while Fe (0.000264) in oyster contributed the highest daily intake. Total hazard quotient (THQ) values for the heavy metals followed descending order of Cu > Hg > Zn > Fe >Mn> Cr. The major risk contributor in terms of organism was clam with 33.20%. It is concluded that the mean heavy metal levels in muscle tissues of the examined species do not pose any threat (THQ< 1) as far as human health is concerned.
The Purple Mangrove Crab, Goniopsis pelii is one of the more elusive crab species inhabiting most... more The Purple Mangrove Crab, Goniopsis pelii is one of the more elusive crab species inhabiting most of the microhabitats in the mangrove ecosystem of Southern Nigeria. This study was carried out to investigate the size composition, growth pattern, diets, and reproductive biology of G. pelii from Abule-Eledu mangrove swamp in Lagos Lagoon, Nigeria. A total of 116 specimens were studied. Data revealed that the carapace length and total weight ranged from 2.5 to 4.9 cm (3.72 ± 0.39) and from 11 to 37 g (23.90 ± 4.21) respectively. The crab exhibited negative allometric growth pattern (b<3), and the carapace length-weight relationship was positively correlated (r = 0.577-0.900). The condition factor (K) ranged from 3.5-8.0 (male), 3.2-7.5 (female) and 3.4-8.0 (sexes combined). The highest K-values were recorded for the smaller size group (2.5-2.9 cm). In terms of sex, the male has the higher K-value (8.0). Identified food particles included plant materials, algae, detritus, diatoms, and protozoa. The sex ratio was 1:0.57 (male: female), and was significantly different from the theoretical ratio of 1:1. Fecundity ranged between 1.9 and 2.8 million eggs with egg diameter ranging from 0.26 to 0.38 mm. Crabs with partial gonad development were predominant in the mangrove, while adults with fully ripe gonads were encountered occasionally throughout the study period. In this study, the reproductive indices and body conditions are indicators of a viable population.
Journal of Agricultural Economics, Environment and Social Sciences , 2020
This study assessed the information sources and cues of food quality at customer interest before ... more This study assessed the information sources and cues of food quality at customer interest before the purchase of shellfish in Lagos metropolis, Nigeria. Shellfish is a broad description for aquatic invertebrate possessing a hard outer covering which include the molluscs (oysters, clams and snails) and the crustaceans (shrimps, prawns, lobsters and crabs). A total of 240 questionnaires were distributed between October and December 2019, while 218 were retrieved and 201 were analysed using descriptive statistics. The majority of the respondents were females (77.61%) with age range of 18-30 years. Among the sampled population, 45.27% had secondary education, 67.16% married while over 25% earned a monthly income of less than ₦20,000. Shrimp (28.36%) was the major type of shellfish consumed, although 43.78% consumed shellfish occasionally while buying majorly from fish market (58.71%). The main source of information on shellfish quality was fish mongers (39.30%) and nutritional composition (32.34%) was the most often used information cues for purchase decision. Awareness on information of shellfish quality in the study area is on the high side although consumption can still be regarded to be low, considering the percentage that purchases shellfish occasionally.
The study evaluated the effect of polystyrene microplastic contaminant on hemato-biochemical para... more The study evaluated the effect of polystyrene microplastic contaminant on hemato-biochemical parameters of Cardiosoma guanhumi from the mangrove area of Lagos Lagoon using standard methods. Total Haemocyte Count (THC) ranged between 3050.00±0.00 mL and 4200.00±0.05 mL with control crabs having the highest value of 4200.00±0.05 mL. There was significant difference between the treatment groups and the control (p<0.05). Hemocyte sub-population variables showed that crabs fed the control and 0.01g polystyrene microplastic diets had higher granulocyte and monocyte populations but a decrease in agranulocytes. The crabs fed with the polystyrene microplastic contaminated diets were significantly higher in serum protein (32.50±0.05-32.90±0.10 gL-1) than the crab fed with control diet (20.09±0.05 gL-1). Crabs fed 0.01g and 0.02g polystyrene microplastic based diets recorded the same aspartate aminotransferase mean value (19.30 µI-1) which was significantly higher than the mean value (11.50 µI-1) recorded in crabs fed control diet. Crab fed 0.01 g polystyrene microplastic based diet recorded most of the highest values for biochemical parameters: Alanine aminotransferase (13.00±0.05 µI-1), alkaline phosphatase (113.70±0.10 µI-1), lactate dehydrogenase (148.60±0.05 µI-1) and urea (40.41 ±0.15 µI-1). The changes in the crabs' hematological and serum biochemical profiles in this study provide reliable and discriminatory data on the effect of microplastic contaminant calling for long-term monitoring to assess the eco-health of the mangrove system.
Journal of Scientific Research and Development , 2020
The jumbo lump is the only part of the crab that can be hand-picked as a whole piece, having a so... more The jumbo lump is the only part of the crab that can be hand-picked as a whole piece, having a soft texture and a delicate and unique flavour. This research was aimed at studying the colour type, oleic acid and functional properties of minced and whole jumbo lump of the Smooth Swim Crab, Portunus validus using standard methods. Lightness values of minced and whole jumbo lump of the Smooth Swim Crab were over 80% higher than that of yellowness and redness. The oleic acid content followed decreasing order as whole berried female) > Minced non-berried female > minced berried female > whole non-berried female > whole male > minced male with respective % values of 2.98, 2.78, 2.58, 2.33, 2.19 and 1.98. Significantly (P<0.05) higher water absorption capacity (117.90±0.03 %) oil absorption capacity (67.10±0.10 %), swelling power (340.80±2.43%) and wettability (28.67±0.58 sec) were recorded in the minced jumbo lump while foam stability, 30.00±0.04 % was significantly lower than 40.00±0.05 % obtained in whole jumbo lump of non-berried female Smooth Swim Crab. The study suggests that the minced and whole of cooked jumbo lump have similar properties. Boiling of the Smooth Swim Crab resulted in harder jumbo lump whole pieces.
Meat quality in terms of its nutritional value, is a major factor when considering dietary items.... more Meat quality in terms of its nutritional value, is a major factor when considering dietary items. This study highlighted the proximate and mineral compositions in the meat of Land Crab, Cardiosoma armatum (Herklots, 1851) fed with Trash Fish (Natural feed) and formulated diet for three (3) months. The meat proximate composition of both crabs fed the two different diets was similar, and there was no significant difference in the crude protein, fat and fiber contents of the meat (p > 0.05). The diets had no significant effects on magnesium, sodium, potassium and phosphorus contents of the meat. Crabs fed formulated diet had significantly higher calcium content of 20428.52±0.10 mg/100 g, compared with the crabs fed with Trash Fish of 18541.83±0.10 mg/100 g (p < 0.05). The pattern of mineral contents in both crabs was calcium > phosphorus > magnesium > sodium > potassium. This study suggested no negative effects of formulated diet on the meat quality. Therefore, formulated diet could be used for fattening of Land Crabs.
Shellfish has become a worldwide delicacy amongst seafood lovers due to its essential nutrients w... more Shellfish has become a worldwide delicacy amongst seafood lovers due to its essential nutrients which are beneficial to human health. An investigative study was carried out on eight different shellfish-White Shrimp (Penaeus occidentalis), Tiger Shrimp (Penaeus monodon), Pink Shrimp (Farfantepenaeus notialis), Guinean Mantis Shrimp (Squilla aculeata calmani), Royal Spiny Lobster (Pallinurius regius), Lagoon Crab (Callinectes amnicola), Smoothswim Crab (Portunus validus) and Periwinkle (Tympanotonus fuscatus) obtained from Better Life market-exploring their bacterial quality and heavy metal accumulation. The highest Total Bacterial Count (2.71±0.03×10 8 CFU/g) was observed in P. occidentalis while the lowest count (1.00±0.04×10 8 cfu/g) was observed in T. fuscatus. The Total Faecal Count of the shellfishes reduced under 44 0 C temperatures except in P. occidentalis which increased from 1.40±0.05×10 3 to 1.70±0.01×10 3 CFU/g. Although, all identified bacteria (Bacillus spp, Escherichia coli, Lactobacillus spp, Pseudomonas aeruginosa and Klebsiella spp) were found in C. amnicola and T. fuscatus but the most contaminated shellfish was Penaeus occidentalis, with 38.5% E. coli, followed by F. notialis having 37.3% P. aeruginosa. The mean heavy metals concentration occurred in the following decreasing order: Iron> Zinc> Copper> Chromium> Manganese while Cadmium, Lead, Nickel and Arsenic were not detected in most of the samples. The study revealed that frozen shellfish are preserved under unhygienic environment most times and the fact that some levels of toxic metals were found in the samples is a cause for constant monitoring.
Nigerian Journal of Basic and Applied Science , 2019
Shell Morphometry is a fundamental tool for the evaluation of phenotypic stocks. The shell growth... more Shell Morphometry is a fundamental tool for the evaluation of phenotypic stocks. The shell growth pattern and percentage flesh yield of Galatea paradoxa from Itu Creek in Niger Delta were investigated using standard morphometric methods. The mean in centimeter (cm) of 9.71±0.09, 35.02±0.22, 23.21±0.12, 37.11±0.25, 29.31±0.16 and 7.32±0.04 were recorded for shell length, maximum width, maximum height, nacre length, nacre width and hinge length respectively. Mean live weight of 115.70±1.09 g, mean flesh weight of 37.91 ± 0.23g and mean shell weight of 66.82±0.97 g were recorded for this species. Galatea paradoxa showed negative allometric growth (b < 3) while the correlation coefficients (r) in all the shell variables were far below "1", indicating a week correlation between the parameters. About 19% of the live weight of the clam is made up of flesh by weight.
Metal pollution is of global concern due to toxicity effects. This study assessed heavy metal
con... more Metal pollution is of global concern due to toxicity effects. This study assessed heavy metal concentrations in sediment and a species of shrimp, Farfantepenaeus notialis, from Lagos and Epe Lagoons in Nigeria between May and October 2017. Significant variation (p<0.05) was observed between the sampling sites for a number of physicochemical parameters (pH, salinity, transparency and conductivity). The recorded mean salinity value of 15.20±2.75 ‰ (Lagos Lagoon) is typical of an estuary while 0.98±0.05 ‰ (Epe Lagoon) is typical of a freshwater body. Significantly higher values (mgkg-1) of lead (0.04±0.03) and zinc (1.45±0.24) were obtained in sediment of Epe Lagoon when compared to the lead (0.02±0.08) and zinc (0.85±0.03) of Lagos Lagoon sediment. All examined heavy metals were found in the crustacean samples in varying and sometimes very low, but measurable concentrations. The fact that some level of bioaccumulation was found in the examined crustacean is a cause for constant monitoring of the lagoons to eliminate any health risk.
Journal of Bangladesh Agricultural University, 2019
Edible crabs constitute one of the major sources of nutritious food for human nutrition. The stud... more Edible crabs constitute one of the major sources of nutritious food for human nutrition. The study was aimed to examine the protein, amino acid and fatty acid compositions of two edible crabs (Callinectes amnicola and Portunus validus) of Lagos coast, Nigeria. Samples were obtained from the water body, transported in crushed iced insulated containers and analyzed in the laboratory using standard methods. Crude protein varied from 55-68.92% (C. amnicola) and 51.9-67.51% (P. validus) on dry matter basis. Leucine (8.63-9.73g/100 g crude protein) and glutamic acid (12.71-16.19g/100 g crude protein) were the highest concentrated essential and non-essential amino acids, respectively. The coefficient of variation of the amino acid values indicated that C. amnicola has more variations, relative to its mean. The most concentrated saturated fatty acid was palmitic acid in the samples with significantly different (P <0.05) values of 14.32±1.05% (C. amnicola) and 24.52±0.00% (P. validus). With the exception of lauric, arachidic and lignoceric, all saturated fatty acids were more concentrated in P. validus than in C. amnicola. Oleic acid among the monounsaturated fatty acids occupied the highest position in C. amnicola (17.6233±0.04%) and in P. validus (12.4682±0.25%); whereas timnodenic acid was the most concentrated among the polyunsaturated fatty acids, with values of 23.9744±0.48 % (C. amnicola) and 15.7234±0.25 % (P. validus). Both species have reasonable levels of dietary protein and lipid quality.
Egyptian Academic Journal of Biological Sciences B. Zoology, 2019
The physicochemical flux, composition and abundance of crustacean larvae in two mesohaline creeks... more The physicochemical flux, composition and abundance of crustacean larvae in two mesohaline creeks of Lagos Lagoon were investigated. The status of the Physico-chemical parameters indicates a non-significant difference between variables except Alkalinity with Abule-Eledu Creek having significantly higher mean value (144.4±2.2 mg/L) than Abule-Agege Creek (121.9±4.9 mg/L). The transparency values of the creeks increased with a reduction in the amount of rainfall while the water temperature as well as salinity values increased appreciably with the dry season. An increase in conductivity (>190.40 μS/cm) and salinity (>10.50‰) in the dry months for both creeks was also observed. The crustacean larvae were represented by five orders with Calanoida and Cyclopoida (Sub-Class: Copepoda) were the most frequent and notable orders occurring in Abule-Eledu and Abule-Agege creeks respectively. Other crustacean categories such as Mysida, Calanoida and Harpaticoida were also recorded. Total species diversity was14 in Abule-Eledu creek and 17 in Abule-Agege Creek. Shannon-Wiener Index values ranged between 0.90 and 0.96 for Abule-Eledu Creek and between 0.97 and 1.09 for Abule-Agege Creek. With the exception of Menhinick Index and Equitability Index, all other biotic indices were higher in Abule-Agege Creek than Abule-Eledu creek. This study therefore suggests that Calanoida and Cyclopoida which are orders of the subclass Copepoda are the dominant crustacean zooplankton group in the creeks of the Lagos Lagoon
Portunids are decapod crustaceans of high economic importance. Seasonal variation in macronutrien... more Portunids are decapod crustaceans of high economic importance. Seasonal variation in macronutrient and micronutrients contents of Callinectes amnicola from three interconnecting lagoons were investigated using standard methods. The percentages of protein and moisture contents in the flesh were higher than that of the shell, while higher ash and nitrogen free extract were obtained in the shell. Crude fibres was not detected in flesh of C. amnicola but detected in shells with values ranging from 0.30 ±0.72 % (C. amnicola from Lagos Lagoon) to 0.55 ±2.15 % (C. amnicola from Badagry Lagoon). There were statistical differences (P ˂ 0.05) in crude fibre and carbohydrate levels of the crab shell during wet and dry seasons while significant difference exist in protein level only in wet season. Protein showed negative correlations with all the minerals in crabs from Badagry and Epe Lagoons but positive correlation with all examined minerals in Lagos Lagoon crabs. The study demonstrated that Callinectes amnicola is rich in macro-micronutrients and characterized by low lipid content (< 3%). The nutrient biochemical constituents in the crab species vary with season.
The Royal Spiny Lobster, Panulirus regius (De Brito Capello, 1864) is one of the most important m... more The Royal Spiny Lobster, Panulirus regius (De Brito Capello, 1864) is one of the most important marine crustaceans in Nigeria. Pattern of growth, condition factors and the primers for amplification of the mitochondrial DNA of a Palinuridae lobster, Panulirus regius along Nigeria coastal water were investigated from January to June 2017. The specimens ranged in carapace length from 13.1 to 28.3 cm, weighing 53.1 to 195.6g. Length-weight relationship was estimated as W = 0.0145L 1.600 given an allometric growth model. The calculated maximum Fulton's Condition Factor (K F) and Allometric Condition Factor (K A) were 2.5 and 0.0003 respectively. The designed primers were defined in sequences, number of band and percentage polymorphic band. The amplification result showed high polymorphism level based on the banding patterns of the samples. With this species specific primers specimen can be identified using minimal quantities of different tissues with only DNA isolation, PCR and electrophoresis for varieties of biological researches. This study revealed that morphometric characterization coupled with molecular analyses could make proper classification of crustaceans in Nigeria possible to achieve.
The ecological health status of aquatic environment is a determinant for the survival and growth ... more The ecological health status of aquatic environment is a determinant for the survival and growth of organisms within such niche. An investigative study was carried out on four crab species – Cardiosoma armatum, Goniopsis pelli, Callinectes amnicola, Portunus validusinhabiting contaminated sites in Lagos Lagoon- exploring their anti-oxidant defense mechanism in the light of heavy metal concentration in the crab tissues. Amongst the measured heavy metals, cadmium level proved to be significantly highest (P<0.05) with range concentration of 0.42±0.12mg/kg (G. pelli)- 0.79±0.06 mg/kg (C. armatum). Contrastingly, lead was marginally low with concentration below 0.01 mg/kg in all the crab species. Organismal responses to environmental pollution showed a high level of biomarkers. C. armatum was observed to have elevated level of superoxide dismutase (123.04±0.01min/mg/pro), catalase (7.74±0.05min/mg/pro), glutathion transferase (18.21±0.02 Hmol/mg pro), reduced glutathione (2.92±0.04Hmol/mg pro) and glutathione peroxidase (61.85±0.06 Hmol/mg pro) above other species with C. amnicola recording the lowest concentration of the biomarkers. With the low level of heavy metals and corresponding high concentration of these biomarkers, the pollution indices within the study habitat are quite modest.
Nigerian Journal of Agriculture, Food and Environment, 2019
Crabs typically walk sideways because of the articulation of the legs which makes a sidelong gait... more Crabs typically walk sideways because of the articulation of the legs which makes a sidelong gait more efficient. The occurrence, size diameter, growth pattern and allometric condition factor of 233 specimens comprising of 117 for Cardiosoma armatum and 116 for Goniopsis pelii from the mangrove swamps of Abule-Agege Creek, Lagos, Nigeria were investigated using standard morphometric techniques. The size groups 3.5-3.9 cm and 6.0-6.4 cm occurred most for G. pelii and C. armatum respectively. C. armatum is a bigger species ranging in carapace length from 3.00 to 7.40cm and weighed 91.3g to 183.9g, while the carapace length of G. pelii ranged from 2.50 to 4.90 cm and total weight from 11 g to 37 g. C. armatum occurred more in the mangrove swamp and unimodal distribution was exhibited by both crab species. Total length-weight relationship for both crab species showed negative allometric growth (b < 3). There was a weak correlation between carapace length and total weight of C. armatum but G. pelii exhibited strong significant correlation (r = 0.577, P < 0.01). Although, C. armatum had a higher condition factor (5.4-30.2) compared to G. pelii (3.4-8.0) but in both species, the highest K-values were recorded for the small size group and decreased with increase in sizes of the crabs.
African Journal of Agriculture, Technology and Environment , 2020
Serum biochemical profile is often applied as an index of physiological condition of invertebrate... more Serum biochemical profile is often applied as an index of physiological condition of invertebrates and thus provide information about the health status of local populations. The study aimed to establish normal ranges for chosen serum biochemical parameters of gastropod species, Pachymelania fusca (Gmelin, 1791) from Ologe and Badagry Lagoons using standard methods. In terms of water quality, Badagry Lagoon showed significant (P < 0.05) higher values in total dissolved solid (88.45 mg/L), chemical oxygen demand (41.88 mg/L), biological oxygen demand (35.73 mg/L), total suspended solid (100.44 mg/L), total hardness (102.06 mg/L), sulphate (34.31 mg/L) and nitrate (1.43 mg/L). In dry season, P. fusca from Ologe Lagoon had higher activities of aspartate aminotransferase (AST) (29.77±1.78 u/l), alanine aminotransferase (ALT) (11.69±1.68 u/l) and alkaline phosphatase (ALP) (140.58±49.64 u/l) than the activities of that from Badagry Lagoon. In wet season, the activity of ALP in P. fusca from Badagry Lagoon ranged from 63.48 to 118.68, and significantly higher than the range of 39.68 to 104.88 in P. fusca from Ologe Lagoon. Total protein was also higher in P. fusca from Badagry Lagoon, ranging from 10.77 to 42.46 g/L. The haemolymph activity of P. fusca from both studied locations varied across season
Moringa oleifera has impressive range of nutritional and medicinal values which when consumed hav... more Moringa oleifera has impressive range of nutritional and medicinal values which when consumed have influence on hematological profile which is applied as an index of physiological condition of various organisms and thus provide information about the health status of local populations. The study aimed to determine the effects of M. oleifera aqueous leaves extract on the hematology, serum biochemical profile and antioxidant enzyme activities of the burrowing crab, Cardiosoma guanhumi. Thirty juveniles of C. guanhumi (Average weight 43.20±0.05 g) were tested, where six crabs were randomly selected and distributed per each tank (1 x 1x 0.6m3) of 1litre of water. Different diets containing M. oleifera aqueous extract at inclusion levels of 0.5 ml, 1.0 ml, 1.5 ml, 2.0 ml and control were used to feed the crabs. Total Haemocyte Count ranged between 2733.33±0.90 mL and 6350.00±0.60 mL; there were significant differences among the treatment groups (p < 0.05). Haemocyte sub-population variables showed that crabs fed the control and 2.0ml M. oleifera kg-1 diet had increased in the granulocyte and monocyte populations but a decrease in the agranulocytes. The results of the serum enzymes showed an increase as the level of M. oleifera aqueous extract increases in the diet. Highest superoxide dismutase (75.43 ±21.25 min/mg pro) and catalase activities (2.96±0.18 min/mg pro), malondialdehyde (12.05±2.09 nmol/L) and glutathione concentrations (0.19 ±0.02 μmol/L) were recorded in crabs fed diet T4 (2.0ml M. oleifera kg-1), while the lowest were obtained in crabs fed control diet. The present study showed that the inclusion of M. oleifera aqueous extract up to 1.0ml kg-1 will have immunomodulatory performance on Cardiosoma guanhumi without any deleterious effect on the crab’s health status.
The degree of genetic variation in a population clearly specifies the structure of stocks and the... more The degree of genetic variation in a population clearly specifies the structure of stocks and the probability of sustenance in future. The portunid crab, Callinectes amnicola, is presently managed as a single stock in Nigeria. Hence, genetic heterogeneity in this species from three interconnecting lagoons (Badagry, Lagos and Epe) was analysed using randomly amplified polymorphic DNA technique. The DNA yield and purity across populations ranged from 61.63 to 2983.34 ng/μl and from 1.68 to 1.86 respectively. The six RAPD primers: OPA-04, OPA-05, OPA-09, OPA-11, OPA-17 and OPAB-08 successfully amplified genomic DNA of 30 individual of C. amnicola from 3 populations with 1 region and 999 permutations. 86 RAPD fragments ranging from 96 to 1403 bp in length were generated. With 69 loci, the percentages of polymorphic bands for each primer across all populations were 60.87% (Badagry Lagoon crab), 62.32% (Lagos Harbour crab) and 66.67% (Epe Lagoon crab). Similarity index ranged from 0.848 to 0.893 and genetic distances from 0.114 to 0.165. The variations within and among the crab populations were 78% and 22% respectively. UPGMA Dendogram among C. amnicola populations using Nei’s genetic distance obtained three main clusters, Epe Lagoon, Lagos Harbour and Badagry Lagoon, with seven outliers. The study established a relative geographical heterogeneity and limited gene flow across C. amnicola populations in coastal waters of Lagos, Nigeria.
The Proceedings of the Nigerian Academy of Science, 2020
Sustainable Development Goal 14 aims to increase the protection and sustainable management of coa... more Sustainable Development Goal 14 aims to increase the protection and sustainable management of coastal ecosystems and their resources while addressing threats such as pollution and ocean acidification. Nigeria as a nation with a coastline of approximately 853km facing the Atlantic Ocean is on one hand, at the mercy of the ocean but, on the other hand, the custodian of its resources. These resources like shellfishes sustain us today, and without them future generations will suffer, this is why there is a law against the destructive fishing practices, illegal, unreported and unregulated fishing activities. This article highlights the few priority areas and sustainability challenges for Nigerian shellfish resources as coastal lagoons are fully exploited and increase in harvest of shellfish resources from the lagoons is unlikely. It was noted that despite the availability of regulations, noncompliance by fisher folks has not helped in managing the exploitations. It is therefore recommended that officials need to work with those responsible for social policies, such as employment and other relevant policies, to make sure that the overall government policy direction is coherent and consistent. Also, giving coastal communities access to resources and allowing those access privileges to be traded can help in sustainable management of shellfish resources.
Bulletin UASVM Animal Science and Biotechnologies , 2020
Bivalve mariculture is a type of molluscan farming done in open seawater on racks, rafts or longl... more Bivalve mariculture is a type of molluscan farming done in open seawater on racks, rafts or longlines where naturally occurring phytoplankton serves as a key food item, introduced into the enclosures with the normal circulation of seawater. Increasingly, the reverse trophic interaction is being recognized; dissolved inorganic and organic waste compounds released by metabolically active bivalves can supply phytoplankton with nutrient and energy requirements for their growth. This two-way interaction can be viewed as a type of community symbiosis developed over long evolutionary timescales. The extent to which this affects overall nutrient budgets and thus primary production is related to the system flushing rate and residence time. Here we reviewed the feeding mechanism and nutrient recycling activities of bivalve and also emphasized the role of phytoplankton as a key nutritional live feed in sustainable bivalve mariculture. Bivalves influence nutrient dynamics through direct excretion and indirectly through microbial mediated remineralisation of their organic deposits in the sediments. The quantitative knowledge of bivalve - phytoplankton trophic interactions in coastal waters will inform bivalve mariculture development to effectively serve the needs of both seafood production and ecosystem restoration.
The concentrations of Mn, Cu, Fe, Zn, Hg and Cr were analyzed in the edible part of four species ... more The concentrations of Mn, Cu, Fe, Zn, Hg and Cr were analyzed in the edible part of four species of aquatic molluscs collected in different fish markets in Lagos using standard methods. Assessing the metal levels in periwinkle, oyster, clam and cuttlefish, muscle levels in mg kg-1 of Mn (0.57±0.00), Zn (2.85±0.00) and Cr (0.69±0.01) in clam were significantly higher (p<0.05) than their corresponding values in other examined mollusc species. Lowest mean levels (mg kg −1) of Mn (0.002±0.00), Fe (0.504±0.02) and Cu (0.025±0.00) in oyster, Zn (0.131±0.02) in periwinkle, Hg (0.001±0.00) and Cr (0.004±0.00) in cuttlefish were observed. However, the mean values of Fe, Cu and Hg were not significantly different across samples. The estimated daily intake of heavy metals (mg person-1 day-1) revealed that Mn (0.000001) in oyster and Hg (0.000001) in cuttlefish contributed the lowest daily intake while Fe (0.000264) in oyster contributed the highest daily intake. Total hazard quotient (THQ) values for the heavy metals followed descending order of Cu > Hg > Zn > Fe >Mn> Cr. The major risk contributor in terms of organism was clam with 33.20%. It is concluded that the mean heavy metal levels in muscle tissues of the examined species do not pose any threat (THQ< 1) as far as human health is concerned.
The Purple Mangrove Crab, Goniopsis pelii is one of the more elusive crab species inhabiting most... more The Purple Mangrove Crab, Goniopsis pelii is one of the more elusive crab species inhabiting most of the microhabitats in the mangrove ecosystem of Southern Nigeria. This study was carried out to investigate the size composition, growth pattern, diets, and reproductive biology of G. pelii from Abule-Eledu mangrove swamp in Lagos Lagoon, Nigeria. A total of 116 specimens were studied. Data revealed that the carapace length and total weight ranged from 2.5 to 4.9 cm (3.72 ± 0.39) and from 11 to 37 g (23.90 ± 4.21) respectively. The crab exhibited negative allometric growth pattern (b<3), and the carapace length-weight relationship was positively correlated (r = 0.577-0.900). The condition factor (K) ranged from 3.5-8.0 (male), 3.2-7.5 (female) and 3.4-8.0 (sexes combined). The highest K-values were recorded for the smaller size group (2.5-2.9 cm). In terms of sex, the male has the higher K-value (8.0). Identified food particles included plant materials, algae, detritus, diatoms, and protozoa. The sex ratio was 1:0.57 (male: female), and was significantly different from the theoretical ratio of 1:1. Fecundity ranged between 1.9 and 2.8 million eggs with egg diameter ranging from 0.26 to 0.38 mm. Crabs with partial gonad development were predominant in the mangrove, while adults with fully ripe gonads were encountered occasionally throughout the study period. In this study, the reproductive indices and body conditions are indicators of a viable population.
Journal of Agricultural Economics, Environment and Social Sciences , 2020
This study assessed the information sources and cues of food quality at customer interest before ... more This study assessed the information sources and cues of food quality at customer interest before the purchase of shellfish in Lagos metropolis, Nigeria. Shellfish is a broad description for aquatic invertebrate possessing a hard outer covering which include the molluscs (oysters, clams and snails) and the crustaceans (shrimps, prawns, lobsters and crabs). A total of 240 questionnaires were distributed between October and December 2019, while 218 were retrieved and 201 were analysed using descriptive statistics. The majority of the respondents were females (77.61%) with age range of 18-30 years. Among the sampled population, 45.27% had secondary education, 67.16% married while over 25% earned a monthly income of less than ₦20,000. Shrimp (28.36%) was the major type of shellfish consumed, although 43.78% consumed shellfish occasionally while buying majorly from fish market (58.71%). The main source of information on shellfish quality was fish mongers (39.30%) and nutritional composition (32.34%) was the most often used information cues for purchase decision. Awareness on information of shellfish quality in the study area is on the high side although consumption can still be regarded to be low, considering the percentage that purchases shellfish occasionally.
The study evaluated the effect of polystyrene microplastic contaminant on hemato-biochemical para... more The study evaluated the effect of polystyrene microplastic contaminant on hemato-biochemical parameters of Cardiosoma guanhumi from the mangrove area of Lagos Lagoon using standard methods. Total Haemocyte Count (THC) ranged between 3050.00±0.00 mL and 4200.00±0.05 mL with control crabs having the highest value of 4200.00±0.05 mL. There was significant difference between the treatment groups and the control (p<0.05). Hemocyte sub-population variables showed that crabs fed the control and 0.01g polystyrene microplastic diets had higher granulocyte and monocyte populations but a decrease in agranulocytes. The crabs fed with the polystyrene microplastic contaminated diets were significantly higher in serum protein (32.50±0.05-32.90±0.10 gL-1) than the crab fed with control diet (20.09±0.05 gL-1). Crabs fed 0.01g and 0.02g polystyrene microplastic based diets recorded the same aspartate aminotransferase mean value (19.30 µI-1) which was significantly higher than the mean value (11.50 µI-1) recorded in crabs fed control diet. Crab fed 0.01 g polystyrene microplastic based diet recorded most of the highest values for biochemical parameters: Alanine aminotransferase (13.00±0.05 µI-1), alkaline phosphatase (113.70±0.10 µI-1), lactate dehydrogenase (148.60±0.05 µI-1) and urea (40.41 ±0.15 µI-1). The changes in the crabs' hematological and serum biochemical profiles in this study provide reliable and discriminatory data on the effect of microplastic contaminant calling for long-term monitoring to assess the eco-health of the mangrove system.
Journal of Scientific Research and Development , 2020
The jumbo lump is the only part of the crab that can be hand-picked as a whole piece, having a so... more The jumbo lump is the only part of the crab that can be hand-picked as a whole piece, having a soft texture and a delicate and unique flavour. This research was aimed at studying the colour type, oleic acid and functional properties of minced and whole jumbo lump of the Smooth Swim Crab, Portunus validus using standard methods. Lightness values of minced and whole jumbo lump of the Smooth Swim Crab were over 80% higher than that of yellowness and redness. The oleic acid content followed decreasing order as whole berried female) > Minced non-berried female > minced berried female > whole non-berried female > whole male > minced male with respective % values of 2.98, 2.78, 2.58, 2.33, 2.19 and 1.98. Significantly (P<0.05) higher water absorption capacity (117.90±0.03 %) oil absorption capacity (67.10±0.10 %), swelling power (340.80±2.43%) and wettability (28.67±0.58 sec) were recorded in the minced jumbo lump while foam stability, 30.00±0.04 % was significantly lower than 40.00±0.05 % obtained in whole jumbo lump of non-berried female Smooth Swim Crab. The study suggests that the minced and whole of cooked jumbo lump have similar properties. Boiling of the Smooth Swim Crab resulted in harder jumbo lump whole pieces.
Meat quality in terms of its nutritional value, is a major factor when considering dietary items.... more Meat quality in terms of its nutritional value, is a major factor when considering dietary items. This study highlighted the proximate and mineral compositions in the meat of Land Crab, Cardiosoma armatum (Herklots, 1851) fed with Trash Fish (Natural feed) and formulated diet for three (3) months. The meat proximate composition of both crabs fed the two different diets was similar, and there was no significant difference in the crude protein, fat and fiber contents of the meat (p > 0.05). The diets had no significant effects on magnesium, sodium, potassium and phosphorus contents of the meat. Crabs fed formulated diet had significantly higher calcium content of 20428.52±0.10 mg/100 g, compared with the crabs fed with Trash Fish of 18541.83±0.10 mg/100 g (p < 0.05). The pattern of mineral contents in both crabs was calcium > phosphorus > magnesium > sodium > potassium. This study suggested no negative effects of formulated diet on the meat quality. Therefore, formulated diet could be used for fattening of Land Crabs.
Shellfish has become a worldwide delicacy amongst seafood lovers due to its essential nutrients w... more Shellfish has become a worldwide delicacy amongst seafood lovers due to its essential nutrients which are beneficial to human health. An investigative study was carried out on eight different shellfish-White Shrimp (Penaeus occidentalis), Tiger Shrimp (Penaeus monodon), Pink Shrimp (Farfantepenaeus notialis), Guinean Mantis Shrimp (Squilla aculeata calmani), Royal Spiny Lobster (Pallinurius regius), Lagoon Crab (Callinectes amnicola), Smoothswim Crab (Portunus validus) and Periwinkle (Tympanotonus fuscatus) obtained from Better Life market-exploring their bacterial quality and heavy metal accumulation. The highest Total Bacterial Count (2.71±0.03×10 8 CFU/g) was observed in P. occidentalis while the lowest count (1.00±0.04×10 8 cfu/g) was observed in T. fuscatus. The Total Faecal Count of the shellfishes reduced under 44 0 C temperatures except in P. occidentalis which increased from 1.40±0.05×10 3 to 1.70±0.01×10 3 CFU/g. Although, all identified bacteria (Bacillus spp, Escherichia coli, Lactobacillus spp, Pseudomonas aeruginosa and Klebsiella spp) were found in C. amnicola and T. fuscatus but the most contaminated shellfish was Penaeus occidentalis, with 38.5% E. coli, followed by F. notialis having 37.3% P. aeruginosa. The mean heavy metals concentration occurred in the following decreasing order: Iron> Zinc> Copper> Chromium> Manganese while Cadmium, Lead, Nickel and Arsenic were not detected in most of the samples. The study revealed that frozen shellfish are preserved under unhygienic environment most times and the fact that some levels of toxic metals were found in the samples is a cause for constant monitoring.
Nigerian Journal of Basic and Applied Science , 2019
Shell Morphometry is a fundamental tool for the evaluation of phenotypic stocks. The shell growth... more Shell Morphometry is a fundamental tool for the evaluation of phenotypic stocks. The shell growth pattern and percentage flesh yield of Galatea paradoxa from Itu Creek in Niger Delta were investigated using standard morphometric methods. The mean in centimeter (cm) of 9.71±0.09, 35.02±0.22, 23.21±0.12, 37.11±0.25, 29.31±0.16 and 7.32±0.04 were recorded for shell length, maximum width, maximum height, nacre length, nacre width and hinge length respectively. Mean live weight of 115.70±1.09 g, mean flesh weight of 37.91 ± 0.23g and mean shell weight of 66.82±0.97 g were recorded for this species. Galatea paradoxa showed negative allometric growth (b < 3) while the correlation coefficients (r) in all the shell variables were far below "1", indicating a week correlation between the parameters. About 19% of the live weight of the clam is made up of flesh by weight.
Metal pollution is of global concern due to toxicity effects. This study assessed heavy metal
con... more Metal pollution is of global concern due to toxicity effects. This study assessed heavy metal concentrations in sediment and a species of shrimp, Farfantepenaeus notialis, from Lagos and Epe Lagoons in Nigeria between May and October 2017. Significant variation (p<0.05) was observed between the sampling sites for a number of physicochemical parameters (pH, salinity, transparency and conductivity). The recorded mean salinity value of 15.20±2.75 ‰ (Lagos Lagoon) is typical of an estuary while 0.98±0.05 ‰ (Epe Lagoon) is typical of a freshwater body. Significantly higher values (mgkg-1) of lead (0.04±0.03) and zinc (1.45±0.24) were obtained in sediment of Epe Lagoon when compared to the lead (0.02±0.08) and zinc (0.85±0.03) of Lagos Lagoon sediment. All examined heavy metals were found in the crustacean samples in varying and sometimes very low, but measurable concentrations. The fact that some level of bioaccumulation was found in the examined crustacean is a cause for constant monitoring of the lagoons to eliminate any health risk.
Journal of Bangladesh Agricultural University, 2019
Edible crabs constitute one of the major sources of nutritious food for human nutrition. The stud... more Edible crabs constitute one of the major sources of nutritious food for human nutrition. The study was aimed to examine the protein, amino acid and fatty acid compositions of two edible crabs (Callinectes amnicola and Portunus validus) of Lagos coast, Nigeria. Samples were obtained from the water body, transported in crushed iced insulated containers and analyzed in the laboratory using standard methods. Crude protein varied from 55-68.92% (C. amnicola) and 51.9-67.51% (P. validus) on dry matter basis. Leucine (8.63-9.73g/100 g crude protein) and glutamic acid (12.71-16.19g/100 g crude protein) were the highest concentrated essential and non-essential amino acids, respectively. The coefficient of variation of the amino acid values indicated that C. amnicola has more variations, relative to its mean. The most concentrated saturated fatty acid was palmitic acid in the samples with significantly different (P <0.05) values of 14.32±1.05% (C. amnicola) and 24.52±0.00% (P. validus). With the exception of lauric, arachidic and lignoceric, all saturated fatty acids were more concentrated in P. validus than in C. amnicola. Oleic acid among the monounsaturated fatty acids occupied the highest position in C. amnicola (17.6233±0.04%) and in P. validus (12.4682±0.25%); whereas timnodenic acid was the most concentrated among the polyunsaturated fatty acids, with values of 23.9744±0.48 % (C. amnicola) and 15.7234±0.25 % (P. validus). Both species have reasonable levels of dietary protein and lipid quality.
Egyptian Academic Journal of Biological Sciences B. Zoology, 2019
The physicochemical flux, composition and abundance of crustacean larvae in two mesohaline creeks... more The physicochemical flux, composition and abundance of crustacean larvae in two mesohaline creeks of Lagos Lagoon were investigated. The status of the Physico-chemical parameters indicates a non-significant difference between variables except Alkalinity with Abule-Eledu Creek having significantly higher mean value (144.4±2.2 mg/L) than Abule-Agege Creek (121.9±4.9 mg/L). The transparency values of the creeks increased with a reduction in the amount of rainfall while the water temperature as well as salinity values increased appreciably with the dry season. An increase in conductivity (>190.40 μS/cm) and salinity (>10.50‰) in the dry months for both creeks was also observed. The crustacean larvae were represented by five orders with Calanoida and Cyclopoida (Sub-Class: Copepoda) were the most frequent and notable orders occurring in Abule-Eledu and Abule-Agege creeks respectively. Other crustacean categories such as Mysida, Calanoida and Harpaticoida were also recorded. Total species diversity was14 in Abule-Eledu creek and 17 in Abule-Agege Creek. Shannon-Wiener Index values ranged between 0.90 and 0.96 for Abule-Eledu Creek and between 0.97 and 1.09 for Abule-Agege Creek. With the exception of Menhinick Index and Equitability Index, all other biotic indices were higher in Abule-Agege Creek than Abule-Eledu creek. This study therefore suggests that Calanoida and Cyclopoida which are orders of the subclass Copepoda are the dominant crustacean zooplankton group in the creeks of the Lagos Lagoon
Portunids are decapod crustaceans of high economic importance. Seasonal variation in macronutrien... more Portunids are decapod crustaceans of high economic importance. Seasonal variation in macronutrient and micronutrients contents of Callinectes amnicola from three interconnecting lagoons were investigated using standard methods. The percentages of protein and moisture contents in the flesh were higher than that of the shell, while higher ash and nitrogen free extract were obtained in the shell. Crude fibres was not detected in flesh of C. amnicola but detected in shells with values ranging from 0.30 ±0.72 % (C. amnicola from Lagos Lagoon) to 0.55 ±2.15 % (C. amnicola from Badagry Lagoon). There were statistical differences (P ˂ 0.05) in crude fibre and carbohydrate levels of the crab shell during wet and dry seasons while significant difference exist in protein level only in wet season. Protein showed negative correlations with all the minerals in crabs from Badagry and Epe Lagoons but positive correlation with all examined minerals in Lagos Lagoon crabs. The study demonstrated that Callinectes amnicola is rich in macro-micronutrients and characterized by low lipid content (< 3%). The nutrient biochemical constituents in the crab species vary with season.
The Royal Spiny Lobster, Panulirus regius (De Brito Capello, 1864) is one of the most important m... more The Royal Spiny Lobster, Panulirus regius (De Brito Capello, 1864) is one of the most important marine crustaceans in Nigeria. Pattern of growth, condition factors and the primers for amplification of the mitochondrial DNA of a Palinuridae lobster, Panulirus regius along Nigeria coastal water were investigated from January to June 2017. The specimens ranged in carapace length from 13.1 to 28.3 cm, weighing 53.1 to 195.6g. Length-weight relationship was estimated as W = 0.0145L 1.600 given an allometric growth model. The calculated maximum Fulton's Condition Factor (K F) and Allometric Condition Factor (K A) were 2.5 and 0.0003 respectively. The designed primers were defined in sequences, number of band and percentage polymorphic band. The amplification result showed high polymorphism level based on the banding patterns of the samples. With this species specific primers specimen can be identified using minimal quantities of different tissues with only DNA isolation, PCR and electrophoresis for varieties of biological researches. This study revealed that morphometric characterization coupled with molecular analyses could make proper classification of crustaceans in Nigeria possible to achieve.
The ecological health status of aquatic environment is a determinant for the survival and growth ... more The ecological health status of aquatic environment is a determinant for the survival and growth of organisms within such niche. An investigative study was carried out on four crab species – Cardiosoma armatum, Goniopsis pelli, Callinectes amnicola, Portunus validusinhabiting contaminated sites in Lagos Lagoon- exploring their anti-oxidant defense mechanism in the light of heavy metal concentration in the crab tissues. Amongst the measured heavy metals, cadmium level proved to be significantly highest (P<0.05) with range concentration of 0.42±0.12mg/kg (G. pelli)- 0.79±0.06 mg/kg (C. armatum). Contrastingly, lead was marginally low with concentration below 0.01 mg/kg in all the crab species. Organismal responses to environmental pollution showed a high level of biomarkers. C. armatum was observed to have elevated level of superoxide dismutase (123.04±0.01min/mg/pro), catalase (7.74±0.05min/mg/pro), glutathion transferase (18.21±0.02 Hmol/mg pro), reduced glutathione (2.92±0.04Hmol/mg pro) and glutathione peroxidase (61.85±0.06 Hmol/mg pro) above other species with C. amnicola recording the lowest concentration of the biomarkers. With the low level of heavy metals and corresponding high concentration of these biomarkers, the pollution indices within the study habitat are quite modest.
Nigerian Journal of Agriculture, Food and Environment, 2019
Crabs typically walk sideways because of the articulation of the legs which makes a sidelong gait... more Crabs typically walk sideways because of the articulation of the legs which makes a sidelong gait more efficient. The occurrence, size diameter, growth pattern and allometric condition factor of 233 specimens comprising of 117 for Cardiosoma armatum and 116 for Goniopsis pelii from the mangrove swamps of Abule-Agege Creek, Lagos, Nigeria were investigated using standard morphometric techniques. The size groups 3.5-3.9 cm and 6.0-6.4 cm occurred most for G. pelii and C. armatum respectively. C. armatum is a bigger species ranging in carapace length from 3.00 to 7.40cm and weighed 91.3g to 183.9g, while the carapace length of G. pelii ranged from 2.50 to 4.90 cm and total weight from 11 g to 37 g. C. armatum occurred more in the mangrove swamp and unimodal distribution was exhibited by both crab species. Total length-weight relationship for both crab species showed negative allometric growth (b < 3). There was a weak correlation between carapace length and total weight of C. armatum but G. pelii exhibited strong significant correlation (r = 0.577, P < 0.01). Although, C. armatum had a higher condition factor (5.4-30.2) compared to G. pelii (3.4-8.0) but in both species, the highest K-values were recorded for the small size group and decreased with increase in sizes of the crabs.
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Papers by Olatunji MORUF Ph.D.
will suffer, this is why there is a law against the destructive fishing practices, illegal, unreported and unregulated fishing activities. This article highlights the few priority areas and sustainability challenges for Nigerian shellfish resources as coastal lagoons are fully exploited and increase in harvest of shellfish resources from the lagoons is unlikely. It was noted that despite the availability of regulations, noncompliance by fisher folks has not helped in managing the exploitations. It is therefore recommended that officials need to work with those responsible for social policies, such as employment and other relevant policies, to make sure that the overall government policy direction is coherent and consistent. Also, giving coastal communities access to resources and
allowing those access privileges to be traded can help in sustainable management of shellfish resources.
concentrations in sediment and a species of shrimp, Farfantepenaeus notialis, from Lagos and Epe
Lagoons in Nigeria between May and October 2017. Significant variation (p<0.05) was observed
between the sampling sites for a number of physicochemical parameters (pH, salinity, transparency
and conductivity). The recorded mean salinity value of 15.20±2.75 ‰ (Lagos Lagoon) is typical of an
estuary while 0.98±0.05 ‰ (Epe Lagoon) is typical of a freshwater body. Significantly higher values
(mgkg-1) of lead (0.04±0.03) and zinc (1.45±0.24) were obtained in sediment of Epe Lagoon when
compared to the lead (0.02±0.08) and zinc (0.85±0.03) of Lagos Lagoon sediment. All examined heavy
metals were found in the crustacean samples in varying and sometimes very low, but measurable
concentrations. The fact that some level of bioaccumulation was found in the examined crustacean is
a cause for constant monitoring of the lagoons to eliminate any health risk.
will suffer, this is why there is a law against the destructive fishing practices, illegal, unreported and unregulated fishing activities. This article highlights the few priority areas and sustainability challenges for Nigerian shellfish resources as coastal lagoons are fully exploited and increase in harvest of shellfish resources from the lagoons is unlikely. It was noted that despite the availability of regulations, noncompliance by fisher folks has not helped in managing the exploitations. It is therefore recommended that officials need to work with those responsible for social policies, such as employment and other relevant policies, to make sure that the overall government policy direction is coherent and consistent. Also, giving coastal communities access to resources and
allowing those access privileges to be traded can help in sustainable management of shellfish resources.
concentrations in sediment and a species of shrimp, Farfantepenaeus notialis, from Lagos and Epe
Lagoons in Nigeria between May and October 2017. Significant variation (p<0.05) was observed
between the sampling sites for a number of physicochemical parameters (pH, salinity, transparency
and conductivity). The recorded mean salinity value of 15.20±2.75 ‰ (Lagos Lagoon) is typical of an
estuary while 0.98±0.05 ‰ (Epe Lagoon) is typical of a freshwater body. Significantly higher values
(mgkg-1) of lead (0.04±0.03) and zinc (1.45±0.24) were obtained in sediment of Epe Lagoon when
compared to the lead (0.02±0.08) and zinc (0.85±0.03) of Lagos Lagoon sediment. All examined heavy
metals were found in the crustacean samples in varying and sometimes very low, but measurable
concentrations. The fact that some level of bioaccumulation was found in the examined crustacean is
a cause for constant monitoring of the lagoons to eliminate any health risk.