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Comparison of pathogenic domains of rabies and African rabies-related lyssaviruses and pathogenicity observed in mice
2013
Joe Kgaladi | Louis H. Nel | Wanda Markotter
Several lyssavirus species occur in Africa (Rabies virus, Lagos bat virus, Mokola virus, Duvenhage virus, Shimoni bat virus and Ikoma lyssavirus), displaying a high sequence diversity between isolates belonging to the same species. There is limited information about comparative pathogenesis of these African lyssaviruses and this precludes authoritative opinion on the potential public and veterinary health impact. In this study, an analysis of representative African lyssaviruses attempted to correlate viral genomic sequence similarities and differences with the corresponding pathogenic profiles observed in mice. The study demonstrated that the virus isolates evaluated could be lethal to mice when introduced intramuscularly and that different isolates of the same lyssavirus species differ in their virulence. Using real-time polymerase chain reaction (PCR), viral RNA was detected in brain tissue, but no viral RNA was detected in the salivary glands or blood of mice that succumbed to infection. Comparison of known pathogenic domains indicated that pathogenicity is likely to be dependent on multiple domains. Cumulatively, our results re-emphasised the realisation that the pathogenicity of a lyssavirus species cannot be deduced based on studies of only a single isolate of the species or a single pathogenic domain.
Mostrar más [+] Menos [-]Lack of evidence for safe vaccination with the Muguga cocktail in Sudan
2013
Dirk Geysen | Dirk Berkvens
<strong>How to cite this article:</strong> Geysen, D. & Berkvens, D., 2013, ‘Lack of evidence for safe vaccination with the Muguga cocktail in Sudan’, <em>Onderstepoort Journal of Veterinary Research</em> 80(1), Art. #571, 1 page. http:// dx.doi.org/10.4102/ojvr. v80i1.571
Mostrar más [+] Menos [-]Spatial variation of epoxyscillirosidine concentrations in <i>Moraea pallida</i> (yellow tulp) in South Africa
2013
Christo J. Botha | Heleen Coetser | Rowena A. Schultz | Leonie Labuschagne | Deon van der Merwe
Moraea pallida (yellow tulp) poisoning is economically the most important intoxication of livestock in South Africa. Poisoning varies according to locality, climatic conditions and growth stage of the plant. The primary objective of this study was to determine the concentration of the toxic principle, epoxyscillirosidine, in yellow tulp leaves and to ascertain the variability of epoxyscillirosidine concentrations within and between different locations. A secondary objective was to utilise Geographic Information Systems in an attempt to explain the variability in toxicity. Flowering yellow tulp plants were collected at 26 sampling points across 20 districts of South Africa. The leaves of five plants per sampling point were extracted and submitted for liquid chromatography/mass spectrometry analysis. A large variation in mean epoxyscillirosidine concentrations, ranging from 3.32 μg/g – 238.27 μg/g, occurred between different geographical regions. The epoxyscillirosidine concentrations also varied tremendously between individual plants (n= 5) collected at the same sampling point, with up to a 24 times difference between the lowest and highest concentration detected. No generalised correlation between epoxyscillirosidine concentrations and soil elemental concentrations could be established. However, samples obtained from the north-eastern part of the sampling region tended to have higher epoxyscillirosidine concentrations compared to samples obtained from the south-western part of the sampling region. Higher toxin concentrations in the northeast were associated with statistically significant higher soil concentrations of iron, bismuth, bromide, cadmium, chromium, rubidium, tellurium, thallium, titanium and zinc, whilst soil concentrations of strontium and soil pH, were significantly lower. This study corroborated the contention that epoxyscillirosidine concentration in yellow tulp fluctuates and may explain the variability in toxicity.
Mostrar más [+] Menos [-]Ethological Problems and Learning Disability due to Aluminium Toxicity in Rats
2013
Amira, A. Goma | U. E. Mahrous
A total of 35 Sprague-Dawley adult rats were used to investigate the effect of aluminium toxicity on behavioural patterns of adult female rats and learning ability of offspring. Rats were allotted into 4 groups, group one received 2g/l anhydrous aluminium chloride (n=10), group two received 3g/l anhydrous aluminium chloride (n=10), group three received 3.5g/l anhydrous aluminium chloride in drinking water (n=10) and control group did not receive anhydrous aluminium chloride (n=5) from 8th day of pregnancy till weaning of pups. The obtained results showed that feeding time increased significantly in 2g/l and 3.5g/l anhydrous aluminium chloride groups than control one, while, litter licking frequency and nursing time increased significantly in 2g/l anhydrous aluminium chloride than other groups. On contrary lying time decreased significantly in rats treated with 2g/l anhydrous aluminium chloride than other groups, licking and scratching decreased in 3g/l and 3.5g/l anhydrous aluminium chloride groups. In considering, the time spent in closed arms by offspring pups exhibited much times significantly than control group, while, time spent in open arms of elevated plus maze decreased significantly in all treated groups than control group. On the other hand, number of entries in open arms significantly decreased in treated groups than control one.
Mostrar más [+] Menos [-]The Hypolipdemic and Antioxidant Effects of Porobiotic, Prebiotics and Natural Lipotropic Factors on Hyperlipidemia and Fatty Liver in Broilers
2013
Doaa S. Mohamed | M. F. El Kady | K. M. Hassanin | K. S. Hashem
Fatty liver is considered a serious problem in broilers as liver is the main organ involved in metabolism of all absorbed substances. In addition, fatty liver has a direct impact on the growth and performance of the chicken. One of the modern approach in controlling metabolic upset, is the use of probiotics, prebiotics in controlling this problems. Here we tried to summarize the protective role of some probiotics, prebiotics and other natural lipotropic factors and their mode of action against hperlipidemia and fatty liver in broilers.
Mostrar más [+] Menos [-]A review of the epidemiology and control of gastrointestinal nematode infections in cattle in Zimbabwe
2013
Davies M. Pfukenyi | Samson Mukaratirwa
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.
Mostrar más [+] Menos [-]Construction and immunogenicity of a ∆apxIC/ompP2 mutant of <i>Actinobacillus pleuropneumoniae</i> and <i>Haemophilus parasuis</i>
2013
Qiong Liu | Yuheng Gong | Yuqin Cao | Xintian Wen | Xiaobo Huang | Qigui Yan | Yong Huang | Sanjie Cao
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 LD<sub>50</sub> data shown that the mutant strain was attenuated 30-fold, compared with the parent strain (LD<sub>50</sub> of the mutant strain and parent strain in mice were determined to be 1.0 × 10<sup>7</sup> CFU and 3.5 × 10<sup>5</sup> 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>
Mostrar más [+] Menos [-]Sero-diagnosis of Bovine Tuberculosis by ELISA Using Bovine PPD and ST.CF
2013
A. El-Sify | M. Nayel | S. Hazem | R. Tarabess | S. Akram | M. Allaam | H. Hassan | M. El Garhy
Bovine tuberculosis represents one of the very important infectious diseases in Egypt and the world. It has zoonotic importance and causes severe economic losses. Accurate and rapid diagnosis considered as the milestone for control of the disease. In this study ELISA technique was used for confirmation of positive reactors cows that tested with single intradermal tuberculin test, to detect false positive reactors. Bovine PPD and ST.CF antigens have been used as two different coating antigens for ELISA technique. 3747 cattle from dairy farms in five different governorates were subjected to the single intradermal cervical tuberculin test whereas 78 (2.24%) proved positive reactors to tuberculin. These positive reactors tested with ELISA. 64 (82.05%) animals were positive by ELISA coated with ST-CF, while by using bovine PPD as coating antigen 58 (74.35%) animals were positive. The previous results indicated that ELISA test showed higher sensitivity and specificity using ST-CF as coating antigen than in case of bovine PPD coating antigen.
Mostrar más [+] Menos [-]Molecular surveillance of <i>Theileria ovis, Theileria lestoquardi</i> and <i>Theileria annulata</i> infection in sheep and ixodid ticks in Iran
2013
Gholamreza Razmi | Saeed Yaghfoori
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.
Mostrar más [+] Menos [-]Notes on the occurrence of <i>Trypanosoma</i> sp. (Kinetoplastida: Trypanosomatidae) in freshwater fishes from South Africa
2013
Maryke L. Ferreira | Annemariè Avenant-Oldewage
A total of 257 fishes from four families, Clariidae, Cichlidae, Cyprinidae and Schilbeidae were collected from three localities: the Sand River Dam, Swaziland; the Nylsvlei Nature Reserve, South Africa and the Vaal Dam and Vaal River Barrage, South Africa. Only fishes (n= 154) from Clariidae and Cichlidae were found to be infected with trypanosomes. A total of 221 Clarias gariepinus (Burchell 1822) were collected from the Vaal Dam and Vaal Barrage area, South Africa. Of these, 74%(89/121) were infected with trypanosomes from the Vaal Dam and 63%(63/100) from the Vaal River Barrage, with no seasonal infection pattern. A prevalence of 25%(1/4) was found in C. gariepinus from the Sand River Dam, Swaziland, and a 50% (1/2) prevalence was found in Tilapia sparrmanii from the Nylsvlei Nature Reserve, South Africa. Standard measurements conformed closely to the morphometric and morphological descriptions of Trypanosoma mukasai. This article provides new locality records for T. mukasai from the Vaal Dam, Vaal River Barrage and Nylsvlei Nature Reserve (South Africa) and the Sand River Dam (Swaziland). Tilapia sparrmanii collected in the Sand River Dam in Swaziland is also noted as a new host record.
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