Comparative Evaluation of Productivity and Cost Effectiveness of Catfish Fingerling Production in Earthen Pond and Recirculation System in Ibadan, Nigeria

Despite the popularity of the African catfish and its great market potentials, the production is still basically at subsistence level due majorly to inadequate supply of seed for stocking. This has been linked to the absence of reliable production techniques for the mass production and rearing of the species under practical farming conditions. The purpose of this study therefore, was to find a suitable culture system for the mass production of catfish (Clarias gariepinus) fingerlings. Protected earthen pond and a unit of recirculation system were used. Fertilized eggs fromfemale were divided into two equal halves and incubated under the same conditions. Forty-nine thousand frys each were stocked into the protected earthen pond and a unit recirculation system respectively. The frys in the two systems were raised for twenty one days and fed the same quantityand quality of feed throughout the period. The survival rate of the frys in the recirculation system was 79% as against 17% in the earthen pond. However, bigger sized (2.2 ± 0.23g) fingerlings were obtained from the earthen pond relative to those cultured in the recirculation system (0.9 ±0.07g). The cost of raising frys in a recirculation system (N34,000) was twice that needed for earthen pond (N17,000), but this was more than made up for in the profit from sales, which was N311,360 and N99,156 respectively. The main reason for fish farming is the expected return tobe, therefore, the choice of income-generating activities, amongst several options available, should be made on the grounds of their expected returns

Evaluation of diazepam-ketamine combination for immobilization of African land tortoise (Testudo graeca)

Zoo and wildlife practitioners are constantly exposed to persistent dangers during physical restraint of wild animals. Chemical immobilization in reptiles is unpredictable due to their ectothermic nature. This study aims to  determine a safe and effective anesthetic protocol for immobilization in chelonians and other reptiles. Varied doses of diazepam ketamine  combinations were administered and evaluated in 16 healthy land tortoises (Testudo graeca). The tortoises were divided into four groups (4 per group) labeled DK-1 through DK-4. DK-1 had a combination of 44mg/kg of  ketamine with 0.25mg/kg of diazepam. DK-2 had 22mg/kg of ketamine with 0.25mg/kg of diazepam. DK-3 had 44mg/kg of ketamine with  0.5mg/kg diazepam while DK-4 had 22mg/kg of ketamine with 0.5mg/kg of diazepam. Anesthetic effects were monitored to determine the duration required for partial extension of the head and limbs, full extension of limbs, and complete recovery from anesthesia. These visual inspection of partial recovery and full extension were adapted as surface and deep anaesthesia respectively in describing the depth of anaesthesia. All the time intervals were recorded in minutes, and summarized as mean and standard deviation. ANOVA was used to test for significance across the groups. Full extension of head and limbs was achieved within mean periods of 10, 15.5 and 13 minutes in DK-1, DK-3 and DK-4 respectively. Tortoises in DK-2, which were only sedated, demonstrated only surface depth of anaesthesia. Complete recovery occurred in mean periods of 128, 25, 158 (p < 0.05) and 132 minutes for groups DK-1, DK-2, DK-3, and DK-4 respectively. Diazepam-Ketamine anaesthetic cocktail provides a safe protocol for chemical restraint in tortoises. A higher dose of diazepam produced a longer duration of complete recovery.Keywords: Anaesthesia, Diazepam, Immobilization, Ketamine, <i>Testudo graeca</i&gt

Blood lead level as biomarker of environmental lead pollution in feral and cultured African catfish (Clarias gariepinus )

Research has demonstrated a positive link between the presence of lead in freshwater, sediments or food organisms and the onset of sub-lethal effects characterized by neurological defects, kidney dysfunction, endocrine disruption, reproductive/developmental defects, behavioural abnormalities and anemia in demersal aquatic fauna. Considering the significance of haematological parameters as indicators of fish health, this present work assessed the blood lead level (BLL) and haematological parameters of feral and cultured African catfish (Clarias gariepinus) in Ibadan, a metropolitan city. BLL and haematological parameters of fifty Clarias gariepinus were determined. Each set of ten fish were randomly collected from three different fish ponds and two rivers. BLL was relatively higher in feral fishes than those from fish ponds; while all the haematological parameters (PCV, HB, RBC, MCH, MCV and MCHC) were non-significantly (

Ultrastuctural study of the phagocytic activities of splenic macrophages in tilapia (Oreochromis niloticus)

The main stages of the phagocytic process after the intraperitoneal injection of colloidal carbon to tilapia (Oreochromis niloticus), was ultra-structurally documented. Carbon particles were initially indiffuse form in the cytoplasm but they gradually formed discrete electron dense bodies that later fused with cytoplasmic granules to form phagolysosomes. Ultra structural results demonstrate that colloidalcarbon is actively phagocytized by cytoplasmic granules (lysosomes) in the spleen of O. niloticus. Direct phagocytic reaction of cells in the presence of an antigen is therefore very important in immunity

Modeling of Reservoir Inflow for Hydropower Dams Using Artificial Neural Network

The stream flow at the three hydropower reservoirs in Nigeria were modeled using hydro-meteorological parameters and Artificial Neural Network (ANN). The model revealed positive relationship between the observed and the modeled reservoir inflow with values of correlation coefficient of 0.57, 0.84 and 0.92 for Kainji, Jebba and Shiroro hydropower reservoir respectively. The established model was used to predict 20 years stream-flow for each of the hydropower reservoirs which were found to have similar statistics with the observed values.  The predicted reservoir inflow were subjected to trend analysis which revealed an upward trend with percentage increase of 4.58%, 6.34% and 5.42% for Kainji, Jebba and Shiroro hydropower reservoirs respectively. The upward trend is an indication of increase in water availability for hydropower generation at the three stations given other constraints are brought under control.http://dx.doi.org/10.4314/njt.v34i1.

Conservation Status and Habitat Preferences of Common Warthog ( Phacochoerus Africanus ) in Old Oyo National Park, Nigeria

This study assessed the conservation status and habitat preference of Common warthog in Old Oyo National Park, Nigeria using direct sighting and line transect method. The abundance estimate and encounter rate of common Warthog in the study area from 2018-2019 showed that year 2018 recorded 213 individuals at an encounter rate of 0.38/km while year 2019 recorded 184 individuals at an encounter rate of 0.32/km while the mean abundance estimate of common Warthog are 4.65\ub10.64 and 1.71\ub10.48 which represents 156 and 58 individuals at encounter rate of 0.55/km and 0.20/km in the wet season and dry season of year 2018 compared to year 2019 with average abundance estimate value of 4.00\ub10.85 and 1.41\ub10.61 which represents 135 and 48 individuals at an encounter rate of 0.47/km and 0.17/km for wet and dry season respectively. The mean age structure and sex ratio of the observed warthog population during dry and wet seasons revealed that juveniles had highest mean of age structures among the populations observed across the seasons. The habitat preference of common warthog revealed that they are mostly found in mixed woodland and open savanna with 112 observation and the lowest was recorded in the outcrop vegetation and open savanna with 21 individuals.in the wet season. During the dry season, mixed woodland/open savanna and Riparian grassland had the highest sightings of 45 and 33 individuals each. The outcrop vegetation/open savanna had the lowest observation of 1 individuals only. The study also recommends that more aspect of the ecology of the animal should be studied in details and emphasis should be placed on the habitat requirements

Assessment of Surface Water Contamination from Coalbed Methane Fracturing-Derived Volatile Contaminants in Sullivan County, Indiana, USA

There is a growing concern over the contamination of surface water and the associated environmental and public health consequences from the recent proliferation in hydraulic fracturing in the USA. Petroleum hydrocarbon-derived contaminants of concern [benzene, toluene, ethylbenzene, and xylene (BTEX)] and various dissolved cations and anions were spatially determined in surface waters around 14 coalbed methane fracking wells in Sullivan County, IN, USA. At least one BTEX was detected in 69% of sampling sites (n=13) and 23% of sampling sites were found to be contaminated with all of the BTEX. Toluene was the most common BTEX compound detected across all sites, both upstream and downstream from coalbed methane fracking sites. The calcium (~60 ppm) and sulfates (~175 ppm) were the dominant cations and anions, respectively, in surface water around the fracking sites. This study represents the first report of BTEX contamination in surface water from coalbed methane hydraulic fracturing wells

An assessment of the levels of phthalate esters and metals in the Muledane open dump, Thohoyandou, Limpopo Province, South Africa

<p>Abstract</p> <p>Background</p> <p>This work reports the determination of the levels of phthalate esters (dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), diethyl hexyl phthalate (DEHP)) and metals (lead, cadmium, manganese, zinc, iron, calcium) in composite soil samples. The soil samples were collected randomly within the Muledane open dump, Thohoyandou, Limpopo province, South Africa. Control samples were collected about 200 m away from the open dump. The phthalate esters were separated and determined by capillary gas chromatography with a flame ionization detector, whilst the metals were determined by atomic absorption spectrophotometry.</p> <p>Results</p> <p>Open dump values for the phthalate esters and metals to be generally higher in comparison to control samples for DMP, DEP, DBP and DEHP – the mean values calculated were 0.31 ± 0.12, 0.21 ± 0.05, 0.30 ± 0.07, and 0.03 ± 0.01 mg/kg, respectively, for the open dump soil samples. Nonetheless, the mean open dump values for lead, cadmium, manganese, zinc, iron and calcium were 0.07 ± 0.04, 0.003 ± 0.001, 5.02 ± 1.92, 0.31 ± 0.02, 11.62 ± 9.48 and 0.12 ± 0.13 mg/kg, respectively. The results were compared statistically.</p> <p>Conclusion</p> <p>Our results revealed that the discarding of wastes into the open dump is a potential source of soil contamination in the immediate vicinity and beyond, <it>via </it>dispersal. Increased levels of phthalate esters and metals in the soil pose a risk to public health, plants and animals. Sustained monitoring of these contaminants is recommended, in addition to upgrading the facility to a landfill.</p