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This study was carried out to assess the distribution, abundance of different tick genera and prevalence of Theileria parva infection in Tarime zebu cattle kept in selected wards of Serengeti and Tarime districts in Mara region. Adult ticks were identified and counted from half body parts of 360 animals which were extensively managed in communal land with natural pastures. Concurrently, blood samples were collected and thereafter DNA extracted and a nested polymerase chain reaction (nPCR) was done using primers specific for p104 gene to detect the presence of T. parva DNA. Ticks were identified into four groups: Amblyomma genus, Boophilus sub-genus of Rhipicephalus genus, other species of Rhipicephalus, and Hyalomma genus. Rhipicephalus genus accounted for 71.8 % of the total ticks, whereas Amblyomma, Boophilus sub-genus of Rhipicephalus genus and Hyalomma constituted 14.1, 14.0 and 0.1 %, respectively. There were more animals ( p < 0.05) infested with ticks in Tarime district (96.1 %) than in Serengeti (61.7 %). The average counts of ticks were higher in adult animals ( p < 0.05) than in young animals. The overall prevalence of T. parva was 27.7 % and was higher ( p < 0.05) in Serengeti (38.3 %) than in Tarime district (16.7 %). However, all animals tested positive for T. parva did not show any clinical signs of East Coast fever (ECF), suggesting the existence of subclinical infection in Tarime zebu. These results suggest that Tarime cattle can tolerate ECF infection and are likely to serve as potential carriers of T. parva to other less-tolerant cattle breeds in mixed herds. Since Tarime cattle are preferred by most farmers with mixed herds, routine screening for T. parva is highly recommended to minimize introduction of infected cattle into an immunologically naive population. [ABSTRACT FROM AUTHOR]

Rift Valley fever (RVF) is an acute mosquito-borne viral zoonotic disease affecting domestic animals and humans caused by the Rift Valley fever virus (RVFV). The virus belongs to the genus Phlebovirus of the family Bunyaviridae. The main aim of this study was to detect the presence of antibodies to RVFV as well as the virus in the serum samples that were collected from livestock during the 2006/2007 RVF outbreaks in different locations in Tanzania. Analysis of selected samples was done using a RVF-specific inhibition enzyme-linked immunosorbent assay (I-ELISA) and reverse transcription polymerase chain reaction (RT-PCR). Genomic viral RNA was extracted directly from serum samples using a QIAamp® Viral RNA Mini Kit (QIAGEN), and a one-step RT-PCR protocol was used to amplify the S segment of RVFV. Positive results were obtained in 39.5 % ( n = 200) samples using the RVF I-ELISA, and 17.6 % ( n = 108) of samples were positive by RT-PCR. I-ELISA detected 41 (38.7 %), 32 (39.0 %), and 6 (50.0 %) positive results in cattle, goats, and sheep sera, respectively, whereas the RT-PCR detected 11 (0.2 %), 7 (0.2 %), and 1 (0.1 %) positive results in cattle, goats, and sheep sera, respectively. These findings have demonstrated the presence of RVFV in Tanzania during the 2006/2007 RVF outbreaks. To our knowledge, this is the first report to detect RVFV in serum samples from domestic animals in Tanzania using PCR technique. Therefore, a detailed molecular study to characterize the virus from different geographical locations in order to establish the profile of strains circulating in the country and develop more effective and efficient control strategies should be done. [ABSTRACT FROM AUTHOR]

Bovine tuberculosis (BTB) is an important neglected zoonosis that affects livestock, wildlife and human. A study to determine prevalence and geospatial clusters for BTB was conducted from June 2010 to March 2012 at livestock-wildlife interface areas (LWIA). A total of 1,288 cattle located in vicinity of Mikumi-Selous ecosystem Tanzania were tested. Single Intradermal Comparative Tuberculin Test and spatial scan statistic analysis were applied to establish the status of the disease and identify significant spatial BTB clusters. Overall individual prevalence was 3.7 % ( n = 1,288) (95 % CI = 2.8-4.9) and 7.8 % (95 % CI = 6.4-9.4) with cut-off of >4 and >2 mm, respectively. Villages with at least one reactor were 55.8 % ( n = 43). Reactivity was significantly higher in Mvomero and Kilosa districts compared with Kilombero and Ulanga districts ( χ = 15.9; P < 0.001). Significant spatial BTB clusters were revealed at 11 villages. BTB clustering was significant in Kilosa and Mvomero districts compared with Kilombero and Ulanga districts. There was overlap and aggregation of BTB clusters covering south and south-east of Kilosa district bordering Mikumi National Park (MNP) and Mvomero. Generally, clustering occurred around major rivers. The current study provides useful information on the dynamics and epidemiological status of BTB around the wildlife-livestock-human interface, it reveals that the wildlife are at risk of BTB from infected livestock. The study revealed hotspots for BTB that can be applied to guide implementation of participatory intervention at LWIA and control strategies in marginalised pastoralist communities. This study calls for similar studies in other Tanzania's LWIA for efficient intervention of BTB countrywide. [ABSTRACT FROM AUTHOR]

A crude resinous extract from Commiphora swynnertonii was tested against an experimental coccidial infection in local chickens. A total of 80 growing chickens were randomly assigned into five groups, which received different treatments. Chickens in G1 were not infected with coccidian oocysts and therefore served as a negative control. All chickens in G2, G3, G4 and G5 were infected through oral administration of coccidian oocysts suspension at a dosed rate of 1.5 × 10 Eimeria spp. oocysts per bird. Starting from day 3 post-infection (p.i), chickens in different groups were treated for 7 consecutive days as follows: G1 and G2 (positive control) received 5 ml of normal saline as placebo, G3 and G4 were given the extract at 400 and 800 mg/kg bodyweight whereas G5 received anticoccidial drug. Clinical signs, bodyweights, oocysts counts and mortality rates were observed regularly. Results showed that oral administration of the resinous extract to chickens with coccidiosis significantly reduced mortality rate from 94 to 25 % and oocysts counts from 1.03 × 10 to 6.55 × 10 oocysts/g faeces ( p < 0.05). Also a body condition score chart indicated less severe clinical signs of the disease in the groups which received the extract. Mean daily body weights were slightly reduced by the administration of the extract but this effect disappeared by day 7 p.i. These findings clearly indicate that resinous extract from C. swynnertonii has significant anticoccidial effect against experimental Eimeria spp. infection in chickens. A larger field trial to validate the use of the extract in chickens naturally infected with Eimeria spp. is required. [ABSTRACT FROM AUTHOR]

Studies were carried out to investigate the effect of crude extracts from resin, leaves, stem barks and root barks of Commiphora swynnertonii against Newcastle disease virus (NDV) using an in ovo assay. Nine-day-old embryonated chicken eggs were divided into seven groups ( n = 6) and received various treatments. Six groups were inoculated with velogenic NDV strain; five groups out of these were treated with different concentrations of the four extracts or a diluent, dimethylsulphoxide. The uninoculated and inoculated groups were left as negative and positive controls, respectively. Embryo survival was observed daily and embryo weights were measured day 5 post-inoculation; a few eggs from selected groups were left to hatch. Allantoic fluid from treated eggs and serum from hatched chicks were collected for hemagglutination and hemagglutination inhibition (HI) tests to detect NDV in the eggs and antibodies against NDV in the hatched chicks respectively. Results showed that embryo survival and mean embryo weight were significantly higher ( p < 0.001) in those groups which were treated with the crude extracts from C. swynnertonii than the positive control group. Also the extracts significantly ( p < 0.001) reduced virus titres, whereas no viruses were detected in the allantoic fluids of the resin-treated group at the highest concentration of 500 μg/mL. Furthermore, the HI test results showed very low levels of antibodies against NDV in chicks hatched from resin and root bark extract-treated eggs suggesting that these plant materials were capable of destroying the NDV before stimulating the developing chick's immunity. The current findings have clearly demonstrated that crude extracts especially that of resin from C. swynnertonii have strong antiviral activity against NDV in ovo. In vivo trials are needed to validate the use of resin from the tree in controlling Newcastle disease in chickens. [ABSTRACT FROM AUTHOR]

Smallholder farmers' knowledge and practice of dairy calf management on 129 farms with calves less than 10 months of age in Southeastern and Southern Highland areas of Tanzania was assessed. The method of study included both a farm visit and completion of a questionnaire. Most of the farmers were female, with a primary level of education, and majority kept 1-3 milking cows that yielded 6-10 l milk/cow/day. Most of the calves were fed milk using a residual calf suckling system. Weaning age was 3-8 months. Overall, the body condition of the calves was poor, ranged from 1 to 2.5 with a mode of 2. The majority of the farmers believed that helminthosis was the most common disease condition affecting the calves; diarrhea was ranked as the second. Calf death was reported by 20% of the farmers to have occurred in their herd lasting the 2 years prior to the study. Calf body condition score was related to body weight for calves younger than 9 weeks, and older than 23 weeks of age, whereas no such relationship existed in the age group 9 to 23 weeks. The sex distribution was skewed with less male calves being older than 23 weeks. We hypothesize that male calves experience inferior management compared with female calves. This study demonstrates a low level of knowledge on, and poor practices of calf management among the surveyed farmers that suggest the need for educational intervention. [ABSTRACT FROM AUTHOR]