Effects of bamboo substrate and supplementary feed on growth and production of the African catfish, Clarias gariepinus

The effects of bamboo poles as substrate for periphyton development on the growth and production of the African catfish, Clarias gariepinus , was evaluated over a period of 90 days. Three treatments, namely manure application as control (C), control and substrate installation (C + S) and, control and substrate with supplementary feeding (C + S + F) were randomly allotted to six earthen ponds each with an area of 100m2. Catfish fingerlings of mean weight 27.5g \ub1 1.25 were stocked at the rate of 80 fish per 100m2. Water temperature, pH, Total Alkalinity, Total Dissolved Solids (TDS), ammonia and nitrites were monitored during the study. The results obtained after a 90- day culture period indicated no significant variations in water quality between treatments. Similarly, there were no significant difference in survival between the treatments which ranged from 81.3%, 96.8% and 86.3% for the C, C+S and C+S+F respectively. The mean gross fish yield (kg/100m2) varied from 16.0kg for C + S, 9.5kg for C + S + F and 6.0kg for C. the study indicated bamboo poles as substrate for periphyton was a superior alternative to improve catfish production under pond conditions

Detection of viable Mycobacterium ulcerans in clinical samples by a novel combined 16S rRNA reverse transcriptase/IS2404 real-time qPCR assay.

Detection of Viable <em>Mycobacterium ulcerans</em> in Clinical Samples by a Novel Combined 16S rRNA Reverse Transcriptase/IS<em>2404</em> Real-Time qPCR Assa

The Current State of the Clam, Galatea paradoxa, Fishery at the Lower Volta River, Ghana

The clam, Galatea paradoxa has for decades been an important source of protein to the riparian communities of the lower Volta River and provides employment to about 2000 people, especially women. The fishing grounds have dwindled from 100 km from the pre-dam era to a narrow stretch of 10 km as a result of the development of sand bars at the estuary. This study was conducted to ascertain the socio-economic importance of the clam fishery to the people of the lower Volta, Ghana. The research found out that there were 251 fishing canoes and 503 fishers engaged in the clam fishery. The average daily catch per fishing canoe was 130 kg of clams, with an annual harvest of 7700 tonnes worth 4,620,408 Ghana Cedis. Commercial extinction of G. paradoxa is imminent in the lower Volta as a result of habitat alteration and overfishing. There is the need to put in place a sustainable harvesting measure that will target medium to large size clams against the current situation where the catch is dominated by smaller clams. It is recommended that a minimum landing size of 50 mm should be imposed. This should be done in consultation with the chiefs and traditional authorities in the communities which have managed the fishery to date. The marketing of clams below the 50 mm shell length limit should be abolished and enforced by the traditional authorities. Secondly, the farming of smaller clams, which is a traditional activity in the estuary, should be encouraged so that fishers who harvest undersize clams can seed them onto their culture plots

Circulating tumor DNA is readily detectable among Ghanaian breast cancer patients supporting non-invasive cancer genomic studies in Africa.

Circulating tumor DNA (ctDNA) sequencing studies could provide novel insights into the molecular pathology of cancer in sub-Saharan Africa. In 15 patient plasma samples collected at the time of diagnosis as part of the Ghana Breast Health Study and unselected for tumor grade and subtype, ctDNA was detected in a majority of patients based on whole- genome sequencing at high (30×) and low (0.1×) depths. Breast cancer driver copy number alterations were observed in the majority of patients

SARS-CoV-2 infections among asymptomatic individuals contributed to COVID-19 cases: A cross-sectional study among prospective air travelers from Ghana

BackgroundThe spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by asymptomatic individuals has been reported since the early stages of the coronavirus disease 2019 (COVID-19) outbreak in various parts of the world. However, there are limited data regarding SARS-CoV-2 among asymptomatic individuals in Ghana. The aim of the study was to use test data of prospective travelers from Ghana as a proxy to estimate the contribution of asymptomatic cases to the spread of COVID-19.MethodsThe study analyzed the SARS-CoV-2 PCR test data of clients whose purpose for testing was classified as “Travel” at the COVID-19 walk-in test center of the Noguchi Memorial Institute for Medical Research (NMIMR) from July 2020 to July 2021. These individuals requesting tests for travel generally had no clinical symptoms of COVID-19 at the time of testing. Data were processed and analyzed using Microsoft Excel office 16 and STATA version 16. Descriptive statistics were used to summarize data on test and demographic characteristics.ResultsOut of 42,997 samples tested at the center within that period, 28,384 (66.0%) were classified as “Travel” tests. Of these, 1,900 (6.7%) tested positive for SARS-CoV-2. The majority (64.8%) of the “Travel” tests were requested by men. The men recorded a SARS-CoV-2 positivity of 6.9% compared to the 6.4% observed among women. Test requests for SARS-CoV-2 were received from all regions of Ghana, with a majority (83.3%) received from the Greater Accra Region. Although the Eastern region recorded the highest SARS-CoV-2 positivity rate of 8.35%, the Greater Accra region contributed 81% to the total number of SARS-CoV-2 positive cases detected within the period of study.ConclusionOur study found substantial SARS-CoV-2 positivity among asymptomatic individuals who, without the requirement for a negative SARS-CoV-2 result for travel, would have no reason to test. These asymptomatic SARS-CoV-2-infected individuals could have traveled to other countries and unintentionally spread the virus. Our findings call for enhanced tracing and testing of asymptomatic contacts of individuals who tested positive for SARS-CoV-2

Population dynamics of the freshwater clam Galatea paradoxa

Population parameters such as asymptotic (L∞), growth coefficient (K), mortality rates (Z,F and M), exploitation level (E) and recruitment pattern of the freshwater clam Galatea paradoxa were estimated using length-frequency data from the Volta River estuary, Ghana. The L∞ for G. paradoxa at the Volta estuary was 105.7 mm, the growth coefficient (K) and the growth performance index (Ǿ) ranged between 0.14–0.18 year-1 and 3.108–3.192, respectively. Total mortality (Z) was 0.65–0.82 year-1, while natural mortality (M) and fishing mortality (F) were 0.35–0.44 year-1 and 0.21–0.47 year-1, respectively, with an exploitation level of 0.32–0.57. The recruitment pattern suggested that G. paradoxa has year-round recruitment with a single pulse over an extended period (October–March) in the Volta River. The Volta River stock of G. paradoxa is overfished and requires immediate action to conserve it. This can be achieved by implementing a minimum landing size restriction and intensifying the culture of smaller clams which is a traditional activity at the estuary

Effects of bamboo substrate and supplementary feed on growth and production of the African catfish, Clarias gariepinus

The effects of bamboo poles as substrate for periphyton development on the growth and production of the African catfish, Clarias gariepinus , was evaluated over a period of 90 days. Three treatments, namely manure application as control (C), control and substrate installation (C + S) and, control and substrate with supplementary feeding (C + S + F) were randomly allotted to six earthen ponds each with an area of 100m2. Catfish fingerlings of mean weight 27.5g ± 1.25 were stocked at the rate of 80 fish per 100m2. Water temperature, pH, Total Alkalinity, Total Dissolved Solids (TDS), ammonia and nitrites were monitored during the study. The results obtained after a 90- day culture period indicated no significant variations in water quality between treatments. Similarly, there were no significant difference in survival between the treatments which ranged from 81.3%, 96.8% and 86.3% for the C, C+S and C+S+F respectively. The mean gross fish yield (kg/100m2) varied from 16.0kg for C + S, 9.5kg for C + S + F and 6.0kg for C. the study indicated bamboo poles as substrate for periphyton was a superior alternative to improve catfish production under pond conditions

Bioaccumulation of heavy metals in the tissue of the clam Galatea paradoxa and sediments from the volta estuary, Ghana

The concentrations of heavy metals, Mn, Zn, Fe and Hg were determined in sediments and in the whole soft tissue of the clam Galatea paradoxa from two clam fishing locations, Ada and Aveglo at the Volta estuary in Ghana from March to September 2008. Thirty clams were obtained from each sampling location monthly and grouped into three size classes of 10 individuals each based on shell lengths as follows: small (25-40mm), medium (41-55mm), and large (above 55mm). Metal concentrations in the tissues of the different clam size-classes from the two stations were similar and did not vary significantly.A comparative evaluation of the metal concentrations in the clams and sediments however, revealed significant variations in concentrations for Zn, Fe and, Hg. Concentration of Fe in the sediment from Ada for June was 18 times higher than the concentration in the clams similarly, Hg concentrations were approximately 5 times higher in the clam tissues than in the sediments. On the basis of calculated BSAFs the metal enrichment in the tissues of the clams rank in the following order Hg>Mn>Fe. The BSAFs indicated a significant accumulation of Hg in the clam tissues relative to the concentrations of other metals in the sediments. The concentrations of the studied metal in the clam and sediment samples are similar to those observed in areas under low pollution impact and the current the levels of contamination of these metals in the estuary do not exceed the clams′ capacity of regulation