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Beadell J.S.,Yale University | Hyseni C.,Yale University | Abila P.P.,National Livestock Resources Research Institute | Azabo R.,National Livestock Resources Research Institute | And 6 more authors.
PLoS Neglected Tropical Diseases | Year: 2010

Background: Glossina fuscipes fuscipes, a riverine species of tsetse, is the main vector of both human and animal trypanosomiasis in Uganda. Successful implementation of vector control will require establishing an appropriate geographical scale for these activities. Population genetics can help to resolve this issue by characterizing the extent of linkage among apparently isolated groups of tsetse. Methodology/Principal Findings: We conducted genetic analyses on mitochondrial and microsatellite data accumulated from approximately 1000 individual tsetse captured in Uganda and neighboring regions of Kenya and Sudan. Phylogeographic analyses suggested that the largest scale genetic structure in G. f. fuscipes arose from an historical event that divided two divergent mitochondrial lineages. These lineages are currently partitioned to northern and southern Uganda and co-occur only in a narrow zone of contact extending across central Uganda. Bayesian assignment tests, which provided evidence for admixture between northern and southern flies at the zone of contact and evidence for northerly gene flow across the zone of contact, indicated that this structure may be impermanent. On the other hand, microsatellite structure within the southern lineage indicated that gene flow is currently limited between populations in western and southeastern Uganda. Within regions, the average FST between populations separated by less than 100 km was less than ∼0.1. Significant tests of isolation by distance suggested that gene flow is ongoing between neighboring populations and that island populations are not uniformly more isolated than mainland populations. Conclusions/Significance: Despite the presence of population structure arising from historical colonization events, our results have revealed strong signals of current gene flow within regions that should be accounted for when planning tsetse control in Uganda. Populations in southeastern Uganda appeared to receive little gene flow from populations in western or northern Uganda, supporting the feasibility of area wide control in the Lake Victoria region by the Pan African Tsetse and Trypanosomiasis Eradication Campaign. © 2010 Beadell et al. Source

El Imam A.H.,Health Science University | Taha K.M.,Animal Resources Research Corporation
Jordan Journal of Biological Sciences | Year: 2015

Malignant Ovine Theileriosis (MOT) is a tick borne disease of sheep and goats, caused by Theileria lestoquardi and is considered a major constraint for sheep production in many areas of the world. It has been reported to infect lymphocytes in vivo and in vitro and the schizonts differentiate into macro-schizonts and micro-schizonts. To date, little is known about the mechanisms involved in the disease pathogenesis, but its high mortality is likely to be linked to the ability of T. lestoquardi to stimulate uncontrolled proliferation of the infected leukocyte. Consequently, severe tissue destruction and pulmonary oedema leading to respiratory failure are thought to be the cause of death. Despite an immense amount of small ruminant research, MOT remains an important disease of sheep and goats. Therefore, the present review outlines the current knowledge covering T. lestoquardi transmission, distribution, pathogenesis, diagnosis and control. The information may assist in filling the gaps in our knowledge about the economic impact of the disease and new research initiatives. We conclude that the development of a simple, affordable and applicable diagnostic test for an early detection at the field level, and the production of an effective vaccine could have a significant impact on the control of the disease. © 2015 Jordan Journal of Biological Sciences. Source

Ibrahim K.E.,King Saud University | Khan H.A.,King Saud University | Omer F.A.,Animal Resources Research Corporation
Experimental and Toxicologic Pathology | Year: 2014

Iminodipropionitrile (IDPN) is a prototype nitrile compound that produces excitation, chorea and circling (ECC) syndrome in rodents. Previous studies have implicated vestibular hair cell degeneration in IDPN-induced behavioral abnormalities. Although the pathological changes in vestibular labyrinth of IDPN-treated rats are well documented, the effects of IDPN on other organ systems are not clearly understood. We therefore examined the histopathological alterations in inner ear, brain, liver and kidneys of rats exposed to IDPN. Adult male Wistar rats were divided into two groups of six animals each. Control rats received normal saline whereas the IDPN group was treated with IDPN (100. mg/kg, i.p.) daily for 7 days. All the animals were carefully observed for any behavioral abnormality and the dyskinetic movements including the vertical and horizontal head weaving, circling and backward walking were quantified. The animals were sacrificed on day 9 and the samples of cochlea, brain, liver and kidney were collected for histopathology. The results showed a direct correlation between the severity of behavioral deficits and the cellular damage in crista ampullaris in IDPN-treated rats. Histopathology of liver was severely influenced by IDPN treatment, leading to vacuolization of cytoplasm, distorted sinusoids, infiltration of mononuclear cells and necrotic zones. However, the severity of hepatic damage in IDPN-treated rats was independent of the magnitude of vestibular hair cell degeneration as well as the severity of behavioral deficits. Administration of IDPN in the vestibulotoxic doses did not produce any histological changes in the brain cortex and kidneys of rats. © 2013 Elsevier GmbH. Source

Aboagla E.M.-E.,Animal Resources Research Corporation | Maeda T.,Hiroshima University
Theriogenology | Year: 2011

Arbutin (4-hydroxyphenyl-glucopyranoside) is a glycosylated hydroquinone present in high concentrations in the leaves of several plants capable of surviving prolonged, extreme dehydration. Two experiments were conducted to determine the effects of arbutin on cryopreservation of goat sperm. In Experiment 1, goat sperm were frozen in extenders with various ratios of Tris-citric acid-glucose (TCG) and arbutin; concentrations of the latter were 0.0 (only TCG), 0.1, 0.2, 0.3, and 0.4 M (only arbutin)]. All extenders had 20% (v/v) egg yolk (EY) and 4% (v/v) glycerol (osmolality = 370 mOsm, pH = 7.0). Sperm motility and acrosome integrity were assessed using CASA, and fluorescein isothiocyanate-labeled peanut agglutinin (FITC-PNA), respectively. Percentages of motile and progressively motile sperm improved with the addition of arbutin; results were optimal (89.0 and 70.0%, respectively; P < 0.05), with 0.4 M arbutin. Furthermore, arbutin improved (P < 0.05) post-thaw recovery rates for both motility and progressive motility. After incubation for 3 h, motility of frozen-thawed washed sperm improved (70%, P < 0.05) with arbutin in the extender. The percentage of sperm with an intact acrosome peaked (77.2%, P < 0.05) with 0.4 M arbutin in the extender. In Experiment 2, the percentage of cells with merocyanine 540/Yo-Pro staining was higher in sperm treated with arbutin than with TCG (P < 0.05), with the best result (58.0%) with 0.4 M arbutin; therefore, arbutin increased membrane fluidity. In conclusion, substitution of a TCG-EY diluent composition with arbutin improved freezability of goat sperm (apparently due to increased membrane fluidity). Furthermore removal of arbutin by centrifugation after freezing and thawing increased sperm longevity. © 2011 Elsevier Inc. Source

Elhussein A.M.,Animal Resources Research Corporation
Parasitology Research | Year: 2010

Theileria-free Hyalomma anatolicum larvae were fed on a naturally infected sheep with Theileria lestoquardi. Resulting flat nymphs of the tick were able to transmit T. lestoquardi infection upon feeding to 3/3 susceptible sheep. Adults emerging from the same batch of larvae were also infective to 3/3 susceptible sheep when they had the infection during their larval feeding. Transmission of T. lestoquardi to sheep was confirmed through clinical monitoring, examination of blood and lymph node biopsy smears, serology using indirect immunoflourescent test, and molecular using polymerase chain reaction technique. © 2010 Springer-Verlag. Source

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