Sublethal Effects of Organophosphate Chlorpyrifos on Hemato-Immunological Parameters of the Gercacinid Crab, Cardiosoma armatum (Herklots, 1851)

Low insecticide exposure has been shown to cause profound effects on non-target organisms, including crabs. Therefore, the changes in hematological parameters, serum biochemistry and antioxidant enzymes in the Gercacinid crab, Cardiosoma armatum were assessed during 28-day exposure to four concentrations of organophosphate chlorpyrifos (0.003, 0.006, 0.03 and 0.06 mg/l). The results showed a significant (P= 0.0) decrease in packed cell volume and total haemocyte count of the exposure crabs (except in 0.003 mg/l concentration) compared to control group. There were no significant changes in hemocyte sedimentation rate, granulocyte and agranulocyte, although all exposure groups increased in hemocyte sedimentation rate and agranulocyte with respective ranges of 3.00-3.02 mm/hr and 64.00-67.00 %. Except for alkaline phosphatase, there were no significant variation in the biochemical profile of both the control crabs and exposure crabs, although organophosphate chlorpyrifos exposure induced increase in all the measured biochemical parameters. The serum protein level and the activities of the enzymes (superoxide dismutase, catalase and malondialdehyde) were inhibited in exposure groups. The changes in these hemato-immunological parameters of the crabs were suitable biomarkers of a sub-lethal exposure to chlorpyrifos at the concentrations tested, and this will be useful in biomonitoring of aquatic environment

Assessment of heavy metal content in imported and local fish and crustacean species obtained within Lagos Metropolis

Fishes are known for their abilities to concentrate heavy metals in their muscles and since they play important role in human nutrition, they need to be carefully screened to ensure that unnecessary high level of some toxic trace metals are not being transfer to man through their consumption. The study was to evaluate heavy metals (chromium, lead, iron and cadmium) in imported and local species of shrimps, crabs and fish using Atomic Absorption Spectroscopy. The selected imported species were horse mackerelkote fish (Trachurus trachurus), mackerel - titus (Scomber scrombus), croaker (Pseudotolithus typus), smooth swim crab (Portunus validus) and pink shrimp (Farfantepenaeus notialis) while the local species used were; Sole fish (Cynoglossus senegalensis), Tilapia (Oreochromis niloticus), brackish water catfish (Chrysichthys nigrodigitatus), freshwater catfish (Clarias gariepinus), lagoon crab (Callinectes amnicola) and freshwater prawn (Macrobrachium macrobrachion). It was observed that there was no significant difference in the metals (Cd, Pb and Cr) between the imported and local fish species and between imported and local crustacean species. However, these metals concentrated more in the local fish species, O. niloticus (1.846 ± 1.00 mg/100g). The mean heavy metals concentration occurred in the following decreasing order: Fe > Cd > Pb > Cr for all the samples. The mean concentrations of the analyzed heavy metals in the samples were below the maximum permissible limits as recommended by the International Atomic Energy Agency (IAEA), United Nations Environment Program (UNEP) and Federal Environmental Protection Agency (FEPA) for heavy metals in fish.Keywords: Fish, Shrimp, Crab, Heavy metal, Chromium, Lead, Iro

Antioxidant Defense System Alternations in Four Crab Species as a Bio-Indicator of Environmental Contamination

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

Occurrence and variation in the depth of burrows of mangrove crabs around a tropical creek in Nigeria

Mangrove crabs are active burrowers in intertidal sediments of wetland, living beneath drifts and high-tide marks in lagoon shores in many parts of the world. The occurrence, distribution and burrow depths and diameters of the mangrove crabs, Cardisoma armatum and Goniopsis pelii collected from a mangrove wetland of the Lagos Lagoon were investigated between February and July, 2017. Burrows were counted biweekly on permanent square plots marked out in the six stations, while the appearance of new burrows as well as disappearance of old burrows, depths and diameters were recorded. C. armatum was present in all the study sites with a total of 848 specimens and occurred throughout the study period, while G. pelli with a total of 115 specimens occurred in two study sites and during the wet season only. Species ratio was 1: 0.37 while the Chisquared value at 1 d.f and 5 % significant level was 557.93. The depth of the crab burrows across the stations ranged from 16.65 – 33.47 cm with diameter ranging between 4.0 – 6.40 cm. Crab burrows, its occurrence and distribution were observed to be affected by natural and anthropogenic factors. There was a rapid decline in burrows in the month of April when rainfall seized and anthropogenic factors like noise, refuse dumping and construction works also played major roles in determining the dispersion of burrows. Therefore, mangrove crabs and their burrows are greatly influenced by both abiotic and biotic factors.Keywords: Cardisoma armatum, Goniopsis pelii, Mangrove wetland, Burrow, Depth and width, Occurrence, Distributio

Some ecological aspects of the gecarcinid land crab, Cardisoma armatum Herklots, 1851 (Crustacea, Brachyura, Gecarcinidae) from the estuarine region of the Comoe River, Côte d’Ivoire

Cardisoma armatum Herklots, 1851 is a land crab endemic to tropical coastal ecosystems and represents an important fishery resource. C. armatum was collected using traps at the eastern region of the Ebrie lagoon and the estuarine region of the Comoé River in 2009 during the high rainy season extending from mid-May to mid-July and in low dry season from mid-July to September. Some biometric parameters are measured to determine some aspects of population structure and condition of this edible crab. Sexual dimorphism was confirmed with the major chelae of male crabs reaching larger sizes than those of females. The sex ratio that varied with the sampling periods was associated with migrations occurring during the breeding season. Positive, negative, and positive allometric growth patterns were observed for the carapace length-total weight relationship, respectively, in males, females, and the population as a whole. For the carapace width/total weight relationship, negative allometric growth was observed, respectively, in males, females, and the whole population. Our data show an evidence of a serious problem of recruitment in the population of this crab related to degradation of the habitats and heavy harvesting pressures, highlighting the necessity of developing and implanting management and protection strategies of this crustacean.© 2016 International Formulae Group. All rights reserved.Keywords: Cardisoma armatum, Population structure, Condition index, Ebrie lagoon, Comoé River, Côte d’Ivoir

Microbial assemblage of the anatomical parts of gercacinid crab from a tropical mangrove swamp

The microbial assemblage and occurrence in the gut, flesh and shell of Cardisoma armatum, from the tropical mangrove swamp of Lagos Lagoon, Nigeria, was analysed using standard microbiological techniques. The crab gut had the highest total heterotrophic bacteria count and total coliform count with respective significant (p&lt;0.05) values of 6.90 ± 0.16 x104CFU g-1 and 3.45 ± 0.12 x102CFU g-1. Total feacal coliform of the crabs were 0.05 ± 0.00 x102CFU g-1, 0.01 ± 0.00 x102Cfu g-1 and 0.01 ± 0.00 x102CFU g-1 in gut, flesh and shell, respectively. Highest total fungal count of 7.50 ± 0.04 x103CFU g-1 was recorded in the crab shell. The bacteria and fungi species isolated&nbsp;and their frequencies of occurrences in percentage were: Bacillus sp. (21.4 %), Citrobacter sp. (3.6 %) Enterobacter sp. (7.1 %), Escherichia coli (10.7 %), Klesiellia pneumonia (17.9 %), Providencia sp. (3.6 %), Serratia sp. (10.7 %), Staphylococcus aureus (10.7 %), S. epidermis (7.1 %), Vibrio sp. (7.1 %), Aspergillus flavus (8.6 %), Aspergillus fumigatu (5.7 %), Aspergillus niger (40.0 %), Fusarium sp. (14.3 %), Penicillium sp. (5.7 %) and Saccharomyces sp. (25.7 %). The isolation rates in the different anatomical sites of the crab follow the order: guts &gt; flesh &gt; shell and shell &gt; flesh &gt; guts for bacterial and fungi infestation respectively. The results of this study showed that the gercacinid crab, C. armatum in the tropical mangrove of Lagos harbours microorganisms including those that are pathogeni

Growth and immunological profile of gercacinid crab at different sublethal salinity regimes

Salinity is the most variable ecological parameter in the lagoon with daily and seasonal variations. The changes in growth, serum biochemistry and antioxidant enzymes activities of Cardisoma armatum were examined during 84-day exposure to five different sublethal salinities (0, 5, 10, 15 and 20 ppt). At the start of the trial, the crab initial average body weight was not significantly different (P &gt; 0.05). The highest weight gain was recorded in 15 ppt (47.40±1.01 g), followed by 20 ppt, 10 ppt and 5 ppt with no significant differences between them. At the end of 84 days experiment, the crab exhibited the lowest body weight growth (48.29 %) at 0 ppt and the highest (81.04±1.08%) at 10 ppt. The 10 ppt treatment had the highest specific growth rates (0.31±0.11 %/day), followed by 5 ppt, 20 ppt, 15 ppt, and then 0 ppt treatments. Aspartate and alanine aminotransferases significantly decreased after 0 ppt, but mean serum protein value increased with salinity increase. Greater activities of catalase, superoxide dismutase and malondialdehyde were recorded in 5-20 ppt. All the antioxidant enzyme activities (with the exception of glutathione) showed significant differences. Thus, deviation from the brackish water condition adversely affects the growth and immune functions of the gecarcinid, resulting in population decline in reclaimed wetlands