Trypanosomosis is considered as a threat to the ongoing efforts on poverty alleviation in Uganda despite attempts to control it. Understanding current prevalence and level of knowledge of local farmers influences the extent to which they adhere to and the success of existing control interventions. Prevalence of bovine trypanosomosis was determined from a total of 200 cattle blood samples randomly selected and screened for trypanosomes by microhaematocrit centrifugation method (HCT) and blood smear microscopy; a questionnaire was used to establish the level of knowledge and livestock practices. STATA software was used for descriptive data analysis and Ashur's scale to assess farmers' knowledge. Four blood samples (4/200) were positive for trypanosomes by both HCT and smear microscopy techniques giving a prevalence of 2% (95% CI: 1.94－2.06); T. congolense and T. vivax species were identified with T. congolense contributing 75% of all infections. Farmers level of knowledge was low and nomadic farming system was mainly practiced. Trypanosomosis remains an economically important challenge in the study area. There is need to encourage farmers to adopt integrated tick and tsetse control practices by using acaricides that kill both ticks and tsetse and there is need for community sensitization and enhancement of the prevailing trypanosomosis control interventions.

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Neospora caninum is an apicomplexan parasite that causes abortion in cattle and sheep. Dog is the main host of N. caninum and infected one shows neurologic disorders. Accurate diagnosis is important particularly under lacking of treatment and vaccination measures. Herein, we targeted the evaluation of diagnostic ability of recombinant protein NcGRA1(rNcGRA1) for detection of specific antibody (IgG) against N. caninum in mice and dogs. The rNcGRA1 was expressed using the E. coli expression system. Diagnostic ability of rNcGRA1 was tested against experimental mouse and dog sera, as well as field dog sera. Simultaneously, same serum samples were tested against rNcSAG1 and Neospora lysate antigen (NLA)-based iELISA. In the N. caninum experimentally infected mice, specific IgG antibodies to NcGRA1 were detectable from 14 days post infection (dpi), and increased at 28 dpi with no detectable antibody levels in the negative control or Toxoplasma gondii infected-mouse sera. In experimentally infected dog sera, the performance of rNcGRA1 was proficient in demonstrating IgG antibody at 28 dpi. In case of field dog sera (N=18), seropositive rate was 44.4% and 22.2% for rNcGRA1 and rNcSAG1-based iELISAs, respectively. These results show that the rNcGRA1 is a novel useful diagnostic antigen for serological detection of N. caninum in dogs.

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The soil ciliate, Colpoda cucullus, can tolerate various types of environmental stress, including 4,000 Gy gamma radiation, by forming resting cysts (encystment). In this study, we found that C. cucullus resting cycts also were able to tolerate 8,000 Gy gamma radiation. Irradiated wet cysts and dry cysts were morphologically indistinguishable from nonirradiated cysts and were able to successfully revert to vegetative cells (excystment). The viability (i.e., excystment) of dry cysts was higher than that of wet cysts after 8,000 Gy gamma irradiation. However, vegetative cells did not survive 8,000 Gy gamma radiation and decomposed.

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Considering the veterinary and public health significance of T. gondii infection and absence of epidemiological data in West Kordofan, and Blue Nile states in Sudan, a total of 392 serum samples from camel, cattle, sheep and goats in West Kordofan, and Blue Nile states were examined for T. gondii antibodies using Latex agglutination test. The overall seroprevalence was 22.4% (88/392). The seropositivity rate was 13.3% (6/45), 44% (33/75), 61% (22/36), 15.4% (21/136), 6% (6/100) in camels, cattle, sheep and goats and donkeys, respectively. Animal species was the only risk factor of T. gondii seropositivity. The significant higher seroprevalence of T. gondii in sheep and cattle indicates their potential role in the transmission of human toxoplasmosis in Sudan and the widespread contamination of the rural environment in Sudan with Toxoplasma oocysts. Further epidemiological studies, as well as special awareness and educational programs for toxoplasmosis are strongly suggested.

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In parasitic unicellular eukaryotes, the tolerance to the pH (1-1.5) of gastric acid is a crucial survival strategy so that they can proliferate in the intestinal tract. We found that the resting cysts of non-parasitic soil ciliate Colpoda cucullus Nag-1 showed a strong tolerance to both extremely low and high pH. The purpose of this study was to explore the tolerance mechanism to extreme pH. Most cysts were alive after exposure to 0.1 M HCl (pH 1) for 4h, or after exposure to 0.1 M NaOH (pH 13) for 3h. Such tolerance to extreme pH is acquired gradually over several days after encystment induction. The resting cysts were reversibly dehydrated by osmotic pressure when they were transferred from water to 0.1 M HCl or 0.1 M NaOH. This result suggests that H⁺/Cl^- and Na⁺/OH^- may diffuse through the cyst wall to reach the plasma membrane. Acid tolerance was reduced in the presence of protonophore (CCCP), suggesting that less permeability of the cyst plasma membrane to H⁺ may be responsible for acid tolerance.

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