An outbreak of bovine trypanosomiasis in the Blue Nile State, Sudan

<p>Abstract</p> <p>Background</p> <p>In this paper, we report an outbreak of bovine trypanosomiasis in Kurmuk District, Blue Nile State, Sudan that involved an infection with four <it>Trypanosoma </it>species in cattle. The outbreak occurred in June 2010 when indigenous cattle, mainly Kenana and Fulani breed types, crossed the national Sudanese border to Ethiopia and returned. A veterinarian was notified of massive deaths in the cattle populations that recently came from Ethiopia. All animals involved in the outbreak were from the nomadic Fulani group and resident local cattle were not infected and no death has been reported among them. A total of 210 blood samples were collected from the ear vein of cattle. A few samples were also collected from other domestic animals species. Parasitological examinations including hematocrit centrifugation techniques (HCT) and Giemsa-stained thin blood films were carried out. ITS1-PCR, which provides a multi-species-specific diagnosis in a single PCR, was performed.</p> <p>Findings</p> <p>Parasitological examinations revealed that 43% (91/210) of the affected cattle population was infected with two morphologically distinct trypanosomes. Seventy animals (33.3%) were infected with <it>T. vivax </it>and twenty one (10%) with <it>T. congolense</it>. In contrast, ITS1-PCR was able to identify four <it>Trypanosoma </it>species namely <it>T. vivax, T. congolense, T. simiae </it>and <it>T. brucei </it>in 56.7% (80/141). <it>T. brucei </it>showed the highest prevalence of 36.9% (52/141) and the lowest 19% (27/141) was displayed by <it>T. congolense</it>. Furthermore, and because ITS1-PCR could not differentiate between <it>T. brucei </it>subspecies, serum resistance-associated (SRA) gene based PCR was used to detect the human <it>T. brucei rhodesiense </it>in <it>T. brucei </it>positive samples. None of the samples was shown positive for <it>T. b. rhodesiense</it>. The identity of the 400 bp PCR product originating from <it>T. simiae</it>, was further confirmed by sequencing and subsequent phylogenetic analysis.</p> <p>Conclusions</p> <p>The outbreak of bovine trypanosomiasis occurred in the Blue Nile State was caused by mixed infection of two or more <it>Trypanosoma </it>species and the conventional parasitological examinations were not reliable in identifying all the species of <it>Trypanosoma </it>involved in the outbreak. It is difficult to determine the cause of the disease for the reason that the current enzootic situation in the resident cattle in the region is poorly understood. The study concluded that there are at least four species of trypanosomes that caused this outbreak in the Blue Nile State. The presence of mixed infections might have exacerbated the severity of the disease. It is hypothesized that variant parasite type(s) might have been introduced to Sudanese cattle when they crossed to Ethiopia, a tsetse belt region.</p

Capture and release of traveling intrinsic localized mode in coupled cantilever array

A method to manipulate intrinsic localized mode (ILM) is numerically discussed in a nonlinear coupled oscillator array, which is obtained by modeling a microcantilever array. Prior to the manipulation, coexistence and dynamical stability of standing ILMs are first investigated. The stability of coexisting ILMs is determined by a nonlinear coupling coefficient of the array. In addition, the global phase structure, which dominates traveling ILMs, is also changed with the stability. It makes possible to manipulate a traveling ILM by adjusting the nonlinear coupling coefficient. The capture and release manipulation of the traveling ILM is shown numerically

Botulinum toxin: Description of injection techniques and examination of controversies surrounding toxin diffusion

10.1111/j.1600-0404.2007.00931.xActa Neurologica Scandinavica117273-8

Theileria in ruminants

Theileria are important hemoprotozoan parasites of domestic and wild ruminants, transmitted by ixodid ticks leading to diseases which range from mild in apparent reactions to highly fatal diseases. Bovine-infecting T. parva and T. annulata and ovine-infecting T. lestoquardi are of major global economic importance, but other Theileria spp. are also briefly mentioned. Classification of Theileria has been a subject of great controversy without consensus on whether many taxons are different species, synonyms, or subspecies of the same parasite. However, with the development of new molecular tools, many of the outstanding difficulties could be resolved. Theileria have complex life cycles both in the vertebrate host and the tick vector, many of which are not clearly understood. One unique feature of some Theileria is their ability to transform infected host cells into a reversible cancer-like proliferation conferring to them an ability to proliferate without apoptosis. The transformation is not permanent because it can be reversed by treatment with anti-theilerial drugs. Understanding this mechanism could give insights into treatment of cancer. Control of the diseases caused by Theileria has largely relied on chemical drugs either to treat infected hosts or prevent infection by controlling the tick vectors. But resistance to chemicals by the parasites or vectors has led to the development of more sustainable control methods such as live vaccination against the three most pathogenic Theileria spp. of ruminants. Efforts are also under way to develop subunit vaccines against these parasites