scholarly journals Protective efficacy of isometamidium chloride and diminazene aceturate against natural Trypanosoma brucei, Trypanosoma congolense and Trypanosoma vivax infections in cattle under a suppressed tsetse population in Uganda

2004 ◽  
Vol 71 (3) ◽  
Author(s):  
J.W. Magona ◽  
J.S.P. Mayende ◽  
R. Okiria ◽  
N.M. Okuna
Keyword(s):  
Trypanosoma Brucei ◽  
Protective Efficacy ◽  
Trypanosoma Congolense ◽  
Trypanosoma Vivax ◽  
Trypanosome Species ◽  
Diminazene Aceturate ◽  
Tsetse Control ◽  
Tsetse Population ◽  
The Mean ◽  
Mean Time

The protective efficacy of isometamidium chloride (ISMM) and diminazene aceturate (DIM) against Trypanosoma brucei, Trypanosoma congolense and Trypanosoma vivax infections in cattle under a suppressed tsetse population was assessed in southeast Uganda. A total of 66 and 57 trypanosome-infected cattle were treated with ISMM and DIM, respectively together with 177 trypanosomefree animals not treated were followed for 12 months, checked every 4 weeks. There was no statistical difference in the mean time to infection with any trypanosome species in animals treated with ISMM or DIM. However, the mean time to trypanosome infection was significantly longer for treated animals than controls. The mean time to infection with each of the three trypanosome species differed significantly, with the average time to T. vivax infection the lowest, followed by T. congolense and then T. brucei. The protective efficacy of DIM was as good as that of ISMM; implying curative treatments against trypanosomosis are sufficient for combination with tsetse control. Isometamidium chloride or DIM had the highest impact on T. brucei and T. congolense infections in cattle.

scholarly journals Evolutionary diversification of the trypanosome haptoglobin-haemoglobin receptor from an ancestral haemoglobin receptor

eLife ◽  
2016 ◽  
Vol 5 ◽  
Author(s):  
Harriet Lane-Serff ◽  
Paula MacGregor ◽  
Lori Peacock ◽  
Olivia JS Macleod ◽  
Christopher Kay ◽  
...  
Keyword(s):  
Developmental Stage ◽  
Trypanosoma Brucei ◽  
Evolutionary History ◽  
Trypanosoma Congolense ◽  
Tsetse Fly ◽  
Mammalian Host ◽  
Trypanosome Species ◽  
African Trypanosome ◽  
Evolutionary Diversification ◽  
Cellular Changes

The haptoglobin-haemoglobin receptor of the African trypanosome species, Trypanosoma brucei, is expressed when the parasite is in the bloodstream of the mammalian host, allowing it to acquire haem through the uptake of haptoglobin-haemoglobin complexes. Here we show that in Trypanosoma congolense this receptor is instead expressed in the epimastigote developmental stage that occurs in the tsetse fly, where it acts as a haemoglobin receptor. We also present the structure of the T. congolense receptor in complex with haemoglobin. This allows us to propose an evolutionary history for this receptor, charting the structural and cellular changes that took place as it adapted from a role in the insect to a new role in the mammalian host.

scholarly journals Prevalence of Cattle Trypanosomosis and Apparent Density of Its Fly Vectors in Bambasi District of Benishangul-Gumuz Regional State, Western Ethiopia

2020 ◽  
Vol 2020 ◽  
pp. 1-7
Author(s):  
Morka Amante ◽  
Hika Tesgera
Keyword(s):  
Trypanosoma Brucei ◽  
Body Condition ◽  
Apparent Density ◽  
Tsetse Fly ◽  
Meat Production ◽  
Tsetse Flies ◽  
Trypanosoma Vivax ◽  
Trypanosome Species ◽  
Cross Sectional ◽  
Significant Difference

Trypanosomosis is the most serious disease of cattle, which causes great socioeconomic losses in the country. Its socioeconomic impact is reflected on direct losses due to mortality, morbidity, and reduction in milk and meat production, abortion and stillbirth, and also costs associated with combat of the disease are direct losses. A cross-sectional study was carried out to assess the prevalence of cattle trypanosomosis, and the apparent density and distribution of its fly vectors in selected study areas. The methods employed during the study were buffy coat technique for parasitological study and deploying trap for the collection of tsetse flies. A total of 1512 flies were trapped, and among them, 1162 were tsetse flies while 350 were biting flies. Higher apparent density for tsetse fly (7.7 F/T/D) followed by Stomoxys (0.9 F/T/D), Tabanus (0.8 F/T/D), and Hematopota (0.6 F/T/D) was recorded. Out of 638 examined cattle, the overall prevalence of trypanosomosis in the study area was 9.1% (58/638). Out of positive cases, Trypanosoma congolense (7.7%) was the dominant trypanosome species followed by Trypanosoma vivax (0.9%), Trypanosoma brucei (0.2%), and mixed infection of Trypanosoma brucei and Trypanosoma vivax (0.3%). There was no a significant difference (p>0.05) in trypanosome infection between age, sex, and trypanosome species. The prevalence of trypanosomosis on the bases of body condition was 2.8% for poor, 5.5% for medium, and 0.8% for good body condition. The overall prevalence of anemia was (36.8%), and presence of anemia was higher in trypanosome positive animals (62.5%) than in negative animals (34.3%) which is statistically significant (p<0.05, CI = 1.794–5.471). The overall mean packed cell volume (PCV) value for examined animals was 25.84 ± 0.252SE. Mean (PCV) of parasitaemic cattle (9.1%) was significantly (p<0.05) lower than that of aparasitaemic cattle (90%). This survey showed that trypanosomosis is still a core problem for livestock production of the study area. Therefore, more attention should be given to the control of both the disease and its vectors.

scholarly journals Impact assessment of immunology and immunoparasitology research at ILRAD and ILRI.

2020 ◽  
pp. 164-207
Author(s):  
Samuel J. Black ◽  
Cynthia L. Baldwin
Keyword(s):  
Monoclonal Antibodies ◽  
Immune System ◽  
Trypanosoma Brucei ◽  
Subunit Vaccine ◽  
Trypanosoma Congolense ◽  
Theileria Parva ◽  
Trypanosoma Vivax ◽  
Personal Reflections ◽  
The Cost

Abstract This book chapter assesses the research on bovine immunology and immunoparasitology conducted over 42 years, from 1973 to 2015, first at ILRAD (1973-1994) and subsequently at ILRI, which was formed by merging ILRAD and the International Livestock Centre for Africa (ILCA) in 1995. This assessment covers the approaches taken, the performance of research teams, the scientific truths uncovered, the cost-effectiveness of the research undertaken and the practical outcomes achieved, notably, the development of monoclonal antibodies (mAbs) and other tools to better define the bovine immune system. The chapter makes extensive use of citation data along with the personal reflections of scientists who participated in the research and surveys of opinion leaders in the field. The specific scientific goals and achievements of ILRI and its predecessors were as follows: making a substantive contribution to bovine immunology was realistic and has been substantially achieved, measuring the diversity of strains of Theileria parva, Trypanosoma brucei, Trypanosoma vivax and Trypanosoma congolense was realistic and has been substantially achieved, identifying mechanisms of immunity that kill parasites or limit the growth of the above parasites was realistic and has been substantially achieved, and developing an effective subunit vaccine against any of the parasites was an ambitious goal and so far has not been achieved.

scholarly journals Prevalence of bovine trypanosomosis in Central Mozambique from 2002 to 2005

2008 ◽  
Vol 75 (1) ◽  
Author(s):  
E.J.K. Specht
Keyword(s):  
Trypanosoma Brucei ◽  
Infection Rate ◽  
Control Programme ◽  
Trypanosoma Congolense ◽  
Trypanosoma Vivax ◽  
Predominant Species ◽  
Bovine Trypanosomosis ◽  
Blood Smears ◽  
Cattle Infections ◽  
Veterinary Laboratory

The study is the result of analyzing 16 895 blood smears of cattle collected at 180 sites in the provinces of Manica, Sofala, Zambézia and Tete in Mozambique. Of the blood smears 73.9 % were from Manica, 11.8 % from Tete, 8.5 % from Sofala and 5.8 % from Zambézia; 75.6 % of these were collected from smallholder cattle. Infections with trypanosomes were highest in smallholder cattle from Sofala Province with 36.8 % of the 872 blood smears examined positive for trypanosomes, and lowest in cattle of commercial farmers in Manica Province with only 6.2 % of 2 252 blood smears being positive. Trypanosoma congolense was the predominant species, followed by Trypanosoma vivax and Trypanosoma brucei sensu lato. Trypanosoma brucei, which also infects humans, was more frequent in the districts of Buzi, Mutarara and Morrumbala with 15.1 %, 10.5 % and 9.8 % of all examined cattle in 2005 being infected with it, respectively. The results show a significant increase in the infection rate with trypanosomes compared with results obtained in previous years by the Regional Veterinary Laboratory in Manica Province and by the Regional Tsetse and Trypanosomiasis Control Programme in Zambézia, Tete and Sofala provinces.

scholarly journals Subcellular localization of a variable surface glycoprotein phosphatidylinositol-specific phospholipase-C in African trypanosomes.

1987 ◽  
Vol 105 (2) ◽  
pp. 737-746 ◽  
Author(s):  
D J Grab ◽  
P Webster ◽  
S Ito ◽  
W R Fish ◽  
Y Verjee ◽  
...  
Keyword(s):  
Phospholipase C ◽  
Trypanosoma Brucei ◽  
Specific Activity ◽  
Surface Glycoprotein ◽  
Trypanosoma Vivax ◽  
Trypanosome Species ◽  
Phospholipase Activity ◽  
African Trypanosomes ◽  
Variable Surface Glycoprotein ◽  
Variable Surface

African trypanosomes contain a membrane-bound enzyme capable of removing dimyristylglycerol from the membrane-attached form of the variable surface glycoprotein (mfVSG; Ferguson, M. A. J., K. Halder, and G. A. M. Cross, 1985, J. Biol Chem., 260:4963-4968). Although mfVSG phospholipase-C has been implicated in the removal of the VSG from the trypanosome surface (Cardoso de Almeida, M. L., and M. J. Turner, 1983, Nature (Lond.)., 302:349-352; Ferguson, M. A. J., K. Halder, and G. A. M. Cross, 1985, J. Biol Chem., 260:4963-4968), its precise function and subcellular location have not been determined. We have developed a procedure for the separation of the cell fractions and organelles of Trypanosoma brucei brucei (and other trypanosome species) by differential sucrose and isopycnic PercollR centrifugation. These fractions were tested for mfVSG phospholipase activity using Trypanosoma brucei mfVSG labeled with 3H-myristic acid as substrate. The highest enzyme-specific activity was associated with the flagella and evidence is presented to suggest that it is localized in the flagellar pocket. Some activity was also associated with the Golgi complex. These results suggest that the mfVSG phospholipase is localized primarily in the membrane of the flagella pocket and possibly other membrane organelles derived from and associated with this structure, and may be part of the VSG-membrane recycling system in African trypanosomes. The activity of mfVSG phospholipase amongst various trypanosome species was determined. We show that, in contrast to the bloodstream forms of Trypanosoma brucei, cultured procyclic Trypanosoma brucei and bloodstream Trypanosoma vivax had little or no mfVSG phospholipase activity. The activity found in bloodstream forms of Trypanosoma congolense was intermediate between Trypanosoma vivax and Trypanosoma brucei.

scholarly journals Occurrence of multiple drug resistance in Trypanosoma brucei rhodesiense isolated from sleeping sickness patients

2007 ◽  
Vol 74 (1) ◽  
Author(s):  
N. Maina ◽  
J.M. Kagira
Keyword(s):  
Trypanosoma Brucei ◽  
Multiple Drug Resistance ◽  
Prepatent Period ◽  
Sleeping Sickness ◽  
Cross Resistance ◽  
Control Group ◽  
Multiple Drug ◽  
Trypanosoma Brucei Rhodesiense ◽  
Diminazene Aceturate ◽  
The Mean

The occurrence of cross-resistance among melarsoprol-resistant Trypanosoma brucei rhodesiense isolates was investigated in this study. The isolates, T. b. rhodesiense KETRI 237, 2538, 1992, 2709, 2694 and 3530, had been obtained from sleeping sickness patients in Kenya and Uganda between 1960 and 1985. Five groups consisting of six mice each were inoculated intraperitoneally with 105 parasites of each isolate, and 24 h later treated with either melarsoprol, homidium chloride, diminazene aceturate or isometamidium chloride. The control group comprised infected but untreated mice. The mice were monitored for cure for a period of 60 days post-treatment. The mean prepatent period in the control mice was 5 days while the mean survival period was 22 days. Five of the stabilates, KETRI 237, 2538, 2709, 2694, and 3530, were confirmed to be melarsoprol resistant. Cross-resistance was observed, with the majority of the isolates being resistant to homidium chloride (5/6) and diminazene aceturate (5/6), but all were sensitive to isometamidium chloride (6/6). However T. b. rhodesiense KETRI 1992, which was previously considered as melarsoprol resistant, was sensitive to all the drugs tested. In conclusion, our study has revealed the existence of cross-resistance among the melarsoprol resistant isolates which could only be cured by isometamidium.

scholarly journals Epidemiology and Detection of Multiple Drug-Resistant Trypanosoma congolense in Zebu Cattle in Gurage Zone, Southwest Ethiopia

2020 ◽  
Author(s):  
Tilahun Tekle ◽  
Asamenew Tesfaye
Keyword(s):  
Longitudinal Study ◽  
Failure Rate ◽  
Drug Susceptibility ◽  
Trypanosoma Congolense ◽  
Post Treatment ◽  
Multiple Drug ◽  
Zebu Cattle ◽  
African Countries ◽  
Diminazene Aceturate ◽  
The Mean

Abstract Background Trypanosomosis in animal is a major threat for the development of livestock sector in many Africa countries as a result it contributes for the prevailing severe hunger and poverty in most sub-Saharan African countries. The aim of this study is to determine the prevalence and drug susceptibility pattern of Trypanosoma congolense in selected districts in Gurage zone, Ethiopia. Methods A cross-sectional study was carried out in 2000 selected indigenous cattle and eighty (n=80) cattle were selected out of 2000 to carry out drug susceptibility test using longitudinal study. Animals were grouped equally into two (n=40) treatment groups and treated with isometamidium chloride (ISMM) and diminazene aceturate (DIM) according to the manufacturer’s instruction. Sample was collected and the microhaematocrit centrifugation technique was used to determine PCV while trypanosomes were detected using dark-ground phase-microscopy. Results The overall prevalence of trypanosomosis was 4.50% (95% CI=4.28, 4.72) and significantly different among districts (P<0.05) where the highest prevalence (7.1%) was recorded in Abeshege district. The mean PCV for cattle in the longitudinal study (n=80) was 23.2 (95%CI=22.3, 24) with no significance (P>0.05) among the study villages. An overall 37.5% (30/80) drug failure rate was recorded at day 14 post treatment. The failure rate accounted 27.5% (11/40) and 47.5% (19/40) for ISMM and DIM at 14 days post-treatment respectively. Those persistently infected cattle at day 14 were re-treated by exchanging the drug and revealed a failure rate of 26.3% (5/19) and 54.5% (5/11) for ISMM and DA respectively. The mean PCV was variable (P<0.05) before applying treatment (day 0=23.2) and day 28 (PCV=25.09). Conclusions The study revealed that T. congolense developed resistance to ISM and DIM at the given dosage regimen. Therefore, an integrated control approach against the parasite and vectors should be implemented in the area.

scholarly journals Trypanosomatid Genomes Contain Several Subfamilies of ingi-Related Retroposons

2009 ◽  
Vol 8 (10) ◽  
pp. 1532-1542 ◽  
Author(s):  
Frédéric Bringaud ◽  
Matthew Berriman ◽  
Christiane Hertz-Fowler
Keyword(s):  
Trypanosoma Brucei ◽  
Leishmania Major ◽  
Trypanosoma Congolense ◽  
Leishmania Braziliensis ◽  
Site Specificity ◽  
Evolutionary Analysis ◽  
Trypanosoma Vivax ◽  
African Trypanosomes ◽  
Active Elements ◽  
Coding Capacity

ABSTRACT Retroposons are ubiquitous transposable elements found in the genomes of most eukaryotes, including trypanosomatids. The African and American trypanosomes (Trypanosoma brucei and Trypanosoma cruzi) contain long autonomous retroposons of the ingi clade (Tbingi and L1Tc, respectively) and short nonautonomous truncated versions (TbRIME and NARTc, respectively), as well as degenerate ingi-related retroposons devoid of coding capacity (DIREs). In contrast, Leishmania major contains only remnants of extinct retroposons (LmDIREs) and of short nonautonomous heterogeneous elements (LmSIDERs). We extend this comparative and evolutionary analysis of retroposons to the genomes of two other African trypanosomes (Trypanosoma congolense and Trypanosoma vivax) and another Leishmania sp. (Leishmania braziliensis). Three new potentially functional retroposons of the ingi clade have been identified: Tvingi in T. vivax and Tcoingi and L1Tco in T. congolense. T. congolense is the first trypanosomatid containing two classes of potentially active retroposons of the ingi clade. We analyzed sequences located upstream of these new long autonomous ingi-related elements, which code for the recognition site of the retroposon-encoded endonuclease. The closely related Tcoingi and Tvingi elements show the same conserved pattern, indicating that the Tcoingi- and Tvingi-encoded endonucleases share site specificity. Similarly, the conserved pattern previously identified upstream of L1Tc has also been detected at the same relative position upstream of L1Tco elements. A phylogenetic analysis of all ingi-related retroposons identified so far, including DIREs, clearly shows that several distinct subfamilies have emerged and coexisted, though in the course of trypanosomatid evolution, only a few have been maintained as active elements in modern trypanosomatid (sub)species.

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