Editorial

No Abstrac

Editorial

No Abstract

Genetic structure among the local chicken ecotypes of Tanzania based on microsatellite DNA typing

A study was conducted to evaluate the genetic structure of local chicken ecotypes of Tanzania using 20 polymorphic microsatellite DNA markers. A standard PCR was followed by manual genotyping (6% native polyacrylamide gel visualized by silver staining). Phylogenetic analysis of 13 individuals from each of the nine ecotypes named Ching'wekwe, Kuchi, Mbeya, Morogoro-medium, N'zenzegere, Pemba, Singamagazi, Unguja and a White Leghorn breed was performed. The ten populations assorted into nine clusters with chickens from the same ecotype often clustering together. It is concluded that there is high genetic relatedness within indigenous chicken ecotype than between ecotypes. This offers a basic step towards rational decision-making on the modalities of selective breeding without compromising the existence of each unique genetic resource.Key words: Local-chicken, ecotypes, microsatellites, DNA, PCR.African Journal of Biotechnology Vol. 4 (8), pp. 768-77

The evolving landscape of COVID‐19 and post‐COVID condition in patients with chronic lymphocytic leukemia: A study by ERIC, the European research initiative on CLL

In this retrospective international multicenter study, we describe the clinical characteristics and outcomes of patients with chronic lymphocytic leukemia (CLL) and related disorders (small lymphocytic lymphoma and high-count monoclonal B lymphocytosis) infected by SARS-CoV-2, including the development of post-COVID condition. Data from 1540 patients with CLL infected by SARS-CoV-2 from January 2020 to May 2022 were included in the analysis and assigned to four phases based on cases disposition and SARS-CoV-2 variants emergence. Post-COVID condition was defined according to the WHO criteria. Patients infected during the most recent phases of the pandemic, though carrying a higher comorbidity burden, were less often hospitalized, rarely needed intensive care unit admission, or died compared to patients infected during the initial phases. The 4-month overall survival (OS) improved through the phases, from 68% to 83%, p = .0015. Age, comorbidity, CLL-directed treatment, but not vaccination status, emerged as risk factors for mortality. Among survivors, 6.65% patients had a reinfection, usually milder than the initial one, and 16.5% developed post-COVID condition. The latter was characterized by fatigue, dyspnea, lasting cough, and impaired concentration. Infection severity was the only risk factor for developing post-COVID. The median time to resolution of the post-COVID condition was 4.7 months. OS in patients with CLL improved during the different phases of the pandemic, likely due to the improvement of prophylactic and therapeutic measures against SARS-CoV-2 as well as the emergence of milder variants. However, mortality remained relevant and a significant number of patients developed post-COVID conditions, warranting further investigations

Micromechanical Properties of Injection-Molded Starch–Wood Particle Composites

The micromechanical properties of injection molded starch–wood particle composites were investigated as a function of particle content and humidity conditions. The composite materials were characterized by scanning electron microscopy and X-ray diffraction methods. The microhardness of the composites was shown to increase notably with the concentration of the wood particles. In addition,creep behavior under the indenter and temperature dependence were evaluated in terms of the independent contribution of the starch matrix and the wood microparticles to the hardness value. The influence of drying time on the density and weight uptake of the injection-molded composites was highlighted. The results revealed the role of the mechanism of water evaporation, showing that the dependence of water uptake and temperature was greater for the starch–wood composites than for the pure starch sample. Experiments performed during the drying process at 70°C indicated that the wood in the starch composites did not prevent water loss from the samples.Peer reviewe

EFFECT OF SUB-CLINICAL MASTITIS ON MILK YIELD AND COMPOSITION OF DAIRY GOATS IN TANZANIA

ABSTRACT Production of dairy goats is on the increase in East African countries. As in cows, prevalence of mastitis in dairy goats appears to be high but studies on the influence of this disease on milk yield and composition are scarce. This study was, therefore, carried out to determine the effect of sub-clinical mastitis on milk yield and composition in dairy goats of Magadu dairy farm in Morogoro, Tanzania. Does were screened for mastitis using the California Mastitis Test (CMT), milk yield was recorded and 80 ml samples collected for laboratory analyses. A total of 184 quarter milk yield samples were available for analyses. Milk samples were analysed for butterfat (BF) by the Gerber method, crude protein (CP) by the Kjeldahl method, lactose by IDF Standard No.28 method and chloride by titration using silver nitrate solution. Data were analysed using least squares analysis of variance based on General Linear models procedures. The fixed effects considered were CMT score, parity, stage of lactation, sampling occasion and quarter of the udder. Sub-clinical mastitis had a significant negative effect on quarter milk yield (P<0.001). Up to 29.4% milk reduction due to mastitis was recorded. Mastitis had a significant (P<0.05) effect on quarter crude protein, butter fat and chloride percentages but not on lactose content. There was a tendency for CP and chloride percentages to increase with increase in CMT scores. However, the mean chloride value obtained in this study of 0.244 was higher than expected. Further, mastitis significantly reduced BF content of milk from 6.32 in non-mastitic does to 4.91% among those with highest CMT score. The mean lactose percentage was 3.83. Subclinical mastitis had no significant influence on lactose content but there was a tendency for a decrease in this component with increase in severity of mastitis. It is recommended that further studies involving a bigger number of does with clinical mastitis be carried out to substantiate the present findings. Economic losses resulting from mastitis in goats also need to be assessed

Online and Mobile Learning in Poultry Farming in Tanzania

Poultry farming in Tanzania has become a major source of income in families in the rural areas. In earlier days, farmers used only a traditional way of farming by letting free poultry in the morning to fetch for food and later in the evening let them in the chicken barn for shelter. In some cases the farmers were not using vaccination or methods of treatment against diseases, instead they slaughter and eat a fowl if it shows signs of being sick. Currently, this situation is changing due to concerted effort to improve poultry farming in rural Tanzania. One of the many efforts is the deployment of agricultural extension officers they operate as facilitators and communicators, helping farmers in their decision-making and ensuring that appropriate knowledge is implemented in order to obtain the best results. Nowadays, several training are offered but have not reached the rural areas where the extension officers are operating and the residence for the bigger percent of traditional farmers. Introduction of m-learning is believed to be effective in delivering learning materials to agricultural extension officers in the rural areas. This paper explores the impact which can be realized by using m-learning to deliver learning materials to agricultural extension officers who in-turn will guide traditional poultry farmers in rural Tanzania to use professional methods of poultry farming. The learning materials are developed in the Learning Management System (LMS), which is also available via the web, and delivered to the mobile phones