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GENOTOXICITY OF DIAZINON IN MALE ALBINO RATS FED ON DIET SUPPLEMENT WITH CHITOSAN Texto completo
2014
Mohammed J. Alwan | Jihad A. Ahmed
In order to determine the genotoxic effects of diazinon and the role of chitosan to neutralize these effects, our study performed in (24) male rats (Rattus norvegicus) were divided into four groups and treated for (60) days as following, group (A) treated with normal saline and served as control, group (B) treated with [(1/10LD50) 3.8mg/kg. bw] of diazinon, group (C) treated with [(1/10LD50) 3.8mg/kg. bw] of diazinon and fed on diet supplement containing (1gram/1kg ration) chitosan, group (D) fed on diet supplement containing (1gram/1kg ration) chitosan only. The genotoxic effect of diazinon was evaluated by using the micronucleus assay showed increasing of micronucleated polychromatic erythrocytes were (11.6%) in group B, while (7%) in group C . The chromosomal aberration showed increase of presence of chromosomal aberration in group B was (7.5±1.04), while in the group C showed mild elevation in (3.25±0.8). The polymorphism of GSTM1 and GSTT1 genes showed highly incidence of both genes polymorphism in group B was (66.6%) while group C was (50%) . we concluded that diazinon is genotoxic pesticide and chitosan ameliorate it effects.
Mostrar más [+] Menos [-]Occurrence of haemoparasites in cattle in Monduli district, northern Tanzania Texto completo
2014
Isihaka J. Haji | Imna Malele | Boniface Namangala
Haemoparasite infections are among the most economically important cattle diseases in sub-Saharan Africa. The present study investigated the occurrence of haemoparasites in 295 indigenous cattle from five villages (Mswakini, Lake Manyara, Naitolia, Makuyuni and Nanja) of the Monduli district, a wildlife-domestic animal-human interface area in northern Tanzania. The data showed that the overall occurrence of haemoparasites in the sampled cattle was 12.5% (95% CI: 8.7% – 16.3%), involving single and mixed infections with Theileria parva, Anaplasma marginale, Babesia bovis, Trypanosoma vivax and Trypanosoma brucei. The highest haemoparasite occurrence was recorded in Lake Manyara (18.3%; 95% CI: 8.5% – 28.1%), and the lowest was recorded in Nanja (6.5%; 95% CI: 0.4% – 12.6%). This preliminary study, furthermore, provided evidence of the possible arthropod vectors (ticks and tsetse flies) that may be involved in the transmission of haemoparasites to cattle in the Monduli district. It is envisaged that this survey will stimulate more studies to determine the prevalence of haemoparasites in livestock by using more sensitive molecular techniques.
Mostrar más [+] Menos [-]Molecular survey for foot-and-mouth disease virus in livestock in Tanzania, 2008–2013 Texto completo
2014
Raphael S. Sallu | Christopher J. Kasanga | Mkama Mathias | Mmeta Yongolo | Chanasa Mpelumbe-Ngeleja | Misheck Mulumba | Ezekia Ranga | Philemon Wambura | Mark Rweyemamu | Nick Knowles | Donald King
Phylogeography data are of paramount importance in studying the molecular epidemiology dynamics of foot-and-mouth disease virus (FMDV). In this study, epithelial samples and oesophageal-pharyngeal fluids were collected from 361 convalescent animals (cattle and buffaloes) in the field throughout Tanzania between 2009 and 2013. The single plex real-time RT-PCR (qRT-PCR) assay for rapid and accurate diagnosis of FMDV employing the Callahan 3DF-2, 3DF-R primers and Callahan 3DP-1 probe were used. Preparation of the samples was performed according to the OIE manual, with a Kenya O serotype obtained from the attenuated vaccine serving as a positive control and samples collected from healthy animals serving as true negatives. The results indicated that 53.49% of samples (n = 176) were positive for FMDV genome by qRT-PCR, with Ct values ranging from 14 to 32. In addition, molecular typing of the FMDV genome positive samples using serotype specific primers revealed the existence of several serotypes: serotype South Africa Territory 1 (SAT1) (34.25%, n = 60), serotype A (68.92%, n = 98), serotype O (59.20%, n = 98) and SAT2 (54.54%, n = 96). The virus protein 1 sequences analysis for 35 samples was performed and the collective results indicated: 54.28% serotype O, 25.71% serotype A, 14.28% serotype SAT1 and 2.85% serotype SAT2. Therefore in this study, both the phylogenetic trees and spatial distribution of serotypes elucidated the phylodynamics of multiple FMDV field strains in Tanzania and neighbouring countries.
Mostrar más [+] Menos [-]Perceived risk factors and risk pathways of Rift Valley fever in cattle in Ijara district, Kenya Texto completo
2014
Nelson O. Owange | William O. Ogara | Jacqueline Kasiiti | Peter B. Gathura | Sam Okuthe | Rosemary Sang | Hippolyte Affognon | Washington Onyango-Ouma | Tobias T.O. Landmann | Murithi Mbabu
Ijara district in Kenya was one of the hotspots of Rift Valley fever (RVF) during the 2006/2007 outbreak, which led to human and animal deaths causing major economic losses. The main constraint for the control and prevention of RVF is inadequate knowledge of the risk factors for its occurrence and maintenance. This study was aimed at understanding the perceived risk factors and risk pathways of RVF in cattle in Ijara to enable the development of improved community-based disease surveillance, prediction, control and prevention. A cross-sectional study was carried out from September 2012 to June 2013. Thirty-one key informant interviews were conducted with relevant stakeholders to determine the local pastoralists’ understanding of risk factors and risk pathways of RVF in cattle in Ijara district. All the key informants perceived the presence of high numbers of mosquitoes and large numbers of cattle to be the most important risk factors contributing to the occurrence of RVF in cattle in Ijara. Key informants classified high rainfall as the most important (12/31) to an important (19/31) risk factor. The main risk pathways were infected mosquitoes that bite cattle whilst grazing and at watering points as well as close contact between domestic animals and wildlife. The likelihood of contamination of the environment as a result of poor handling of carcasses and aborted foetuses during RVF outbreaks was not considered an important pathway. There is therefore a need to conduct regular participatory community awareness sessions on handling of animal carcasses in terms of preparedness, prevention and control of any possible RVF epizootics. Additionally, monitoring of environmental conditions to detect enhanced rainfall and flooding should be prioritised for preparedness.
Mostrar más [+] Menos [-]Typing and serological surveillance of FMDV in the African buffaloes in Zambia Texto completo
2014
Tingiya Sikombe | Christopher J. Kasanga | Yona Sinkala | Martin Simuunza | John Muma | Rahana Dwarka | Misheck Mulumba | Cornelius Mundia | Aaron Mweene
The changing landscape for health research in Africa: The focus of the Southern African Centre for Infectious Diseases and Surveillance Texto completo
2014
Mark M. Rweyemamu | Esron D. Karimuribo | Leonard E.G. Mboera
Multitoxin analysis of <i>Aspergillus clavatus</i>-infected feed samples implicated in two outbreaks of neuromycotoxicosis in cattle in South Africa Texto completo
2014
Christo J. Botha | Matthew J. Legg | Mariëtte Truter | Michael Sulyok
Aspergillus clavatus intoxication is a highly fatal neuromycotoxicosis of ruminants, especially cattle. It is caused by the ingestion of infected sprouting grain and sorghum beer residue. Locomotor disturbances, tremors and paralysis are observed. Histologically, degeneration and necrosis of larger neurons in the medulla oblongata, the midbrain, the thalamus and the ventral horns of the spinal cord are observed. Although a range of mycotoxins such as patulin, cytochalasin E and pseurotin A have been isolated, there is limited information on which specific mycotoxin or group of mycotoxins are involved during outbreaks of intoxication in livestock. In the present study, two outbreaks of A. clavatus poisoning in cattle are briefly described. Feed samples were collected for fungal identification, and culture and multitoxin analysis. A range of fungal metabolites were detected, and the estimated concentrations (μg/kg) are provided. Both the sprouting barley and brewer’s grain were predominantly infected with A. clavatus and, to a lesser extent, Rhizopus arrhizus. The only common Aspergillus secondary metabolite present in all the samples was pseurotin A. Patulin and cytochalasin E were present in the sprouting barley samples, as well as the A. clavatus isolates cultured on malt extract agar for 2 weeks; however, neither of these mycotoxins could be detected in the brewer’s grain sample.
Mostrar más [+] Menos [-]Acknowledgement to reviewers Texto completo
2014
Editorial Office
Screening for foot-and-mouth disease virus in livestock-wildlife interface areas of Tanzania Texto completo
2014
Emma Peter | Christopher J. Kasanga | Raphael Sallu | Mkama Mathias | Mmeta Yongolo | Misheck Mulumba | Ezekia Ranga | Philemon N. Wambura | Mark M. Rweyemamu
First report of a mixed infection of <i>Trichinella nelsoni</i> and <i>Trichinella</i> T8 in a leopard (<i>Panthera pardus</i>) from the Greater Kruger National Park, South Africa Texto completo
2014
Louis J. La Grange | Björn Reininghaus | Samson Mukaratirwa
At least three Trichinella species, namely Trichinella nelsoni, Trichinella britovi and Trichinella zimbabwensis, and one genotype (Trichinella T8), have been isolated from sylvatic carnivores on the African continent. With the exception of T. britovi, the other species are known to circulate in wildlife of the Kruger National Park (KNP), South Africa, and KNP neighbouring game reserves (collectively known as the greater KNP area). Lions (Panthera leo) and spotted hyenas (Crocuta crocuta) appear to be the most important reservoirs of T. nelsoni and Trichinella T8 in the KNP and surrounding areas. Interspecies predation between lions and hyenas has been implicated as a primary mode of maintaining the life cycles of these two Trichinella species. This is the first report of a mixed natural infection of T. nelsoni and Trichinella T8 in a leopard (Panthera pardus) from South Africa. Trichinella muscle larvae were identified to species level by multiplex polymerase chain reaction (PCR). Probable sources of infection, based on the known dietary preference and prey species’ range of leopards, are also discussed. The described occurrence of Trichinella species in a leopard from the greater KNP area raises the question of possible sources of infection for this predator species.
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