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

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

Genetic diversity among nine free range local chicken ecotypes in Tanzania based on microsatelliteDNA polymorphisms

Tanzania Journal of Agricultural Sciences 2008, Vol. 9(1) : 54 - 68The genetic diversity among nine free-range local chicken ecoivpes identified in Tanzania was evaluated using 20 polymorphic microsatelliies markers. The ecotypes were named Ching'toekuie, Mbeya, Morogoro-medium, Kuchi, Singamagazi, N'zenzegere, Pemba, Tunga, and Unguja. A manual microsatellite typing procedure was adopted. Of the 20 microsaielliie loci, 16 were amplified by PCR and were highly polymorphic. Four to 15 alleles per locus and four to seven alleles per ecotype were detected. Gene diversity was venj high (62 to 79%). The shortest genetic distance as measured by Nei's standard genetic distance (Ds) was between Kuchi and Unguja ecotypes (Ds distance = 0.0671) while the White Leghorn and Unguja ecotype (Ds distance= 0.9149) presented the longest genetic distance. A Neighbour-loining dendogram based on Ds distance showed the local chicken ecotypes to assort into three clusters. The bootstrapping values within the dendogram ranged from 41 to 98%. These results indicate that the free-range local chicken ecotypes to exist in different genetic groups. The accurate genetic typing of this animal genetic resource is important in making rational decisions on the utilisation of the chickens for economical use without compromising the conservation of each unique ecotype adapted to a particular eco-climaiic zone