A study of the prevalence of African horse sickness in horses was conducted, using records from two private equine practices in Harare for the period 1998–2004. Results indicated a higher prevalence of the disease in horses in Zimbabwe in the late rainy season (March – May). Age of the horse was found to be a significant risk factor, with foals or yearlings appearing to be 1.80 times more likely to contract the disease compared with horses older than two years. The case fatality rate in foals or yearlings was also higher than in older age groups, but this difference was not significant. The vaccination status was an important risk factor, with vaccinated horses 0.12 times less likely to die from the disease compared with unvaccinated horses. Young, unvaccinated horses therefore seem to be the most susceptible to the disease and have greater chances of fatality. This study highlights the importance of adequately protecting horses against African horse sickness by providing immunisation through vaccination and discusses the need to review current vaccination strategies being practiced in Zimbabwe.

Cestodes are parasitic flatworms that live in the digestive tract of vertebrates as adults and often in the liver, muscle, haemocoel, mesentery and brain of various animals as larval stages. To identify the cestodes infecting <em>Clarias gariepinus</em> Burchell, 1822 (sharptooth catfish) in the Vaal Dam, a total of 45 host specimens were collected with the aid of gill nets between October 2011, January and April 2012. The fish were sacrificed and examined for cestode parasites. Two adult cestodes, <em>Tetracampos ciliotheca</em> Wedl, 1861 (prevalence 86.7%, mean intensity = 15,<em> n</em> = 45) and <em>Proteocephalus glanduligerus</em> (Janicki, 1928) (prevalence 51.1%, mean intensity = 5, <em>n</em> = 45) were found in the intestines of the catfish. Both <em>T. ciliotheca</em> and <em>P. glanduligerus</em> are new locality records. There were statistically insignificant differences in the infection of the male and female <em>C. gariepinu</em>. Fish with standard length ranging from 40 cm – 54 cm (≥ 3 years) had the highest prevalence and mean intensity while those ranging from 10 cm – 24 cm (&lt; 1 year) had the lowest prevalence and mean intensity for both cestodes. The study highlights the importance of changing feeding habits of <em>C. gariepinus </em>with age on the prevalence and mean intensity of the two gastrointestinal cestode parasites.

In this review, the main gastrointestinal nematodes infecting cattle in Zimbabwe and the epidemiological factors influencing their occurrence are reviewed and discussed. Nineteen gastrointestinal nematode species that belong to seven families have been found to occur in cattle in Zimbabwe. The main genera reported to date are Cooperia, Haemonchus, Trichostrongylus and Oesophagostomumand the dominant species are Cooperia pectinata, Cooperia punctata, Haemonchus placei and Trichostrongylus axei. The mixed infection by several species from the genera is the cause of parasitic gastroenteritis in cattle in Zimbabwe. Production and husbandry practices, season, host age and environment are considered to be the main factors that influence gastrointestinal nematode infection in cattle. The geographical distribution of the gastrointestinal nematodes is also reviewed in relation to the climatic conditions of the country. Various control options are discussed and how they are applicable to the Zimbabwean situation. Based on reports and existing data on the epidemiological features of the gastrointestinal nematode infection in cattle, practical control measures are critically reviewed and recommendations are made for a national control programme.

The attenuated <em>Salmonella typhimurium χ</em>4550 strain was used to harbour a reconstructed bicistronic DNA vaccine against porcine rotavirus, which carried the rotavirus nonstructural protein 4 (<em>NSP4</em>) and VP7 genes simultaneously. Using a balanced lethal system, the kanamycin resistance gene of expressing eukaryotic plasmids pVAX1 and pVAXD were replaced by the aspartate β-semialdehyde dehydrogenase (<em>asd</em>) gene. The NSP4 cleavage product (259–525) of rotavirus OSU strain and VP7 full-length genes were amplified by reverse transcription polymerase chain reaction and then inserted into the eukaryotic single-expression plasmid, pVAX1-asd, and the eukaryotic dual-expression plasmid, pVAXD-asd, respectively. The recombinant plasmids pVAX1-asd-NSP4, pVAX1-asd-VP7 and pVAXD-asd-NSP4-VP7 were transformed into the attenuated <em>S. typhimurium χ</em>4550 strain by electrotransformation. An indirect immunofluorescence assay of the expressed COS-7 cell suggested that the recombinant <em>S. typhimurium χ</em>4550 strain was constructed successfully. The recombinant <em>S. typhimurium χ</em>4550 strain was orally administered to BALB/c mice. The group immunised with dual- expression plasmids produced a significantly higher level of serum Immunoglobulin G (IgG) and intestinal Immunoglobulin A (IgA) than the group immunised with single-expression plasmids. These results indicated that eukaryotic bicistronic plasmid DNA vaccines could be successfully constructed to enhance humoural, mucosal and cellular immune response against rotavirus infection.

A molecular study was undertaken to detect Theileria ovis, Theileria lestoquardi and Theileria annulatain sheep and tick vectors. Investigation was conducted from 2010 to 2011 in the south of Khorasan Razavi Province, Iran. A total of 150 blood samples were collected from 30 different sheep flocks. In addition, ixodid ticks were sampled from the same flocks. The stained blood smears were microscopically examined for the presence of piroplasms and a semi-nested polymerase chain reaction-restriction (PCR) was used for subsequent molecular speciation. Salivary glands were isolated from the ticks and subsequently analysed by semi-nested PCR. polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to differentiate between T. lestoquardi and T. annulata from PCR-positive samples. Theileria species infection was microscopically detected in 18.6% of blood smears. The presence of T. ovis and T. lestoquardi or T. annulata was detected by semi-nested PCR in 58.6% and 6.6% of blood samples respectively. In total, 169 ixodid ticks were collected from different areas of the province. The most prevalent ticks were Rhipicephalus turanicus (n = 155; 91.7% of the total), followed by Hyalomma anatolicum anatolicum (n = 8; 4.7%) and Hyalomma marginatum turanicum (n = 6; 3.5%). From an organ pooling of 33 ticks, three pools of salivary glands from R. turanicus were positive for Theileria species by semi-nested PCR. Of the three R. turanicus samples testing positive for Theileria species, two (6.1%) were positive for T. ovis and one (3.0%) for T. lestoquardi or T. annulata. Amongst the 11 PCR-positive samples for T. lestoquardi or T. annulata, 10 were positive for T. lestoquardi and one sample was positive for both T. lestoquardi and T. annulata using PCR-RFLP. The results also demonstrated that PCR-RFLP could be used for the detection of T. ovis. Based on the results, it can be concluded that T. ovis has a higher prevalence than T. lestoquardi, and that R. turanicus could be a possible vector for T. ovis and T. lestoquardi. Finally, the PCR-RFLP based on Msp1 restriction enzyme is a simple method for differentiation of Theileria species in sheep and ixodid ticks.

Thirty two cattle, had no neurological syndrome, were serologically positive to brucellosis by using Tube agglutination and Rose Bengal Tests, by the official veterinary authority in Beni Suef province, Egypt. These animals were slaughtered in Beni Suef abattoirs during the project of control and eradication of brucella positive animals in Beni Suef province. Postmortem examination was performed and the brain was mechanically removed. Longitudinally the brain was cut; one half was fixed in formalin 25% for 2 weeks and the other one were sent to microbiology department for bacteriological isolation. Transverse sections were done in the fixed tissue and samples were collected from cerebrum, cerebellum, medulla oblongata, thalamus, hypothalamus, and caudate nucleus. These samples were processed according to Bancroft and Gamble (2008). From the thirty two brain samples, no isolates of brucella species were recovered. From the thirty two brain samples, no isolates of brucella species were recovered. Brains of slaughtered animals showed no pathological lesions grossly. Microscopically, inflammatory reactions, degeneration, malacia, demyelination, pigmentation,and vascular changes were detected.

The present study was conducted to assess the prevalence of Giardia species infection in cattle and human. One hundred of animal fecal samples and 139 human stool samples were collected from different veterinary clinics and its related hospitals respectively. All samples were undergone to microscopically examination by; direct smears in 0.90% Na Cl solution, Lugol's iodine stain for cyst detection and formol-ether concentration. 9 (28.1%) calves from 32 were positive in microscopic examination by the used techniques. 25% of the examined fecal samples of cattle (17/68) were containing cysts of Giardia species by microscope. 39 of 139 (28.1%) of human stool samples were found infected by this protozoon. Regarding the sex of human cases, 26.30% of examined males were positive while 30.20% of females were positive. The age factor in human infection was clear; the age group of 11 to 20 years were the more infected than the other group (1- 10ys). There is no relation between form of human stool and infection rate. ELISA kits confirmed that 6 % of animal cases and 15.8% of human were positive. The epidemiological aspects were discussed in the study.

A retrospective serosurvey was carried out between 2009 and 2012 to detect antibodies to Brucella spp. in free-ranging African wildlife ungulates from five selected game parks in Zimbabwe. Samples were drawn from wildlife-livestock interface and non-interface areas in Zimbabwe. A total of 270 serum samples from four different species, namely African buffalo (Syncerus caffer) (n=106), impala (Aepyceros melampus) (n = 72), black rhinoceros (Diceros bicornis) (n= 45) and white rhinoceros (Ceratotherium simum) (n = 47), were tested. The percentage of positive samples was 17.0% in buffalo (18/106; 95% CI: 9.72% – 24.1%) and 1.4% in impala (1/72; 95% CI: 0% – 4.2%). No antibodies to Brucella spp. were detected in the two rhinoceros species. The difference in the percentage of seropositive cases between buffalo and impala was significant (p< 0.05). Seropositivity to Brucella spp. was higher (19.1%) in adult buffalo compared with juveniles and sub-adults younger than six years (5.9%). Further, seropositivity was marginally higher (20.4%) in animals from wildlife-livestock interface areas than in those from non-interface areas (13.45%; OR = 1.45) although the difference was not statistically significant. The study showed that brucellosis could be more widespread in buffalo and may circulate in this species independently in the absence of contact with cattle, whilst rhinoceros may be considered less susceptible to brucellosis. The role of the wildlife-livestock interface in the epidemiology of brucellosis in wildlife and livestock is probably overstated but needs to be explored further.

The apxIC genes of the <em>Actinobacillus pleuropneumoniae</em> serovar 5 (SC-1), encoding the ApxIactivating proteins, was deleted by a method involving sucrose counter-selection. In this study, a mutant strain of <em>A. pleuropneumoniae</em> (SC-1) was constructed and named DapxIC/ ompP2. The mutant strain contained foreign DNA in the deletion site of ompP2 gene of <em>Haemophilus parasuis</em>. It showed no haemolytic activity and lower virulence of cytotoxicity in mice compared with the parent strain, and its safety and immunogenicity were also evaluated in mice. The LD₅₀ data shown that the mutant strain was attenuated 30-fold, compared with the parent strain (LD₅₀ of the mutant strain and parent strain in mice were determined to be 1.0 × 10⁷ CFU and 3.5 × 10⁵ CFU respectively). The mutant strain that was attenuated could secrete inactivated ApxIA RTX toxins with complete antigenicity and could be used as a candidate live vaccine strain against infections of <em>A. pleuropneumoniae</em> and <em>H. parasuis.</em>

Objective: To compare the feasibility and repeatability of tissue Doppler imaging (TDI) for quantification of radial left ventricular (LV) velocity and deformation from different imaging planes and to correlate cardiac event timing data obtained by TDI to M-mode and pulsed-wave Doppler-derived time intervals in horses. Animals: 10 healthy adult horses. Procedures: Repeated echocardiography was performed by 2 observers from right and left parasternal short-axis views at papillary muscle and chordal levels. The TDI measurements of systolic and diastolic velocity, strain rate, strain peak values, and timing were performed in 8 LV wall segments (LV free wall and interventricular septum from right parasternal views; left and right region of LV wall from left parasternal views). The inter- and intraobserver within- and between-day variability and measurement variability were assessed. The correlation between TDI-based measurements and M-mode and pulsed-wave Doppler-based time measurements was calculated. Results: TDI measurements of velocity, strain rate, and strain were feasible in each horse, although deformation could often not be measured in the LV free wall. Systolic and diastolic time intervals could be determined with low to moderate variability, whereas peak amplitude variability ranged from low to high. The TDI-based time measurements were significantly correlated to M-mode and pulsed-wave Doppler measurements. Conclusions and Clinical Relevance: TDI measurements of radial LV velocity and deformation were feasible with low to moderate variability in 8 LV segments. These measurements can be used for evaluating LV function in further clinical studies.