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Molecular surveillance of spotted fever group rickettsioses in wildlife and detection of Rickettsia sibirica in a Topi (Damaliscus lunatus ssp. jimela) in Kenya Полный текст
2017
Ndeereh, David(Kenya Wildlife Service Department of Veterinary Services) | Thaiyah, Andrew(University of Nairobi Department of Clinical Studies) | Muchemi, Gerald(University of Nairobi Department of Public Health, Pharmacology and Toxicology) | Miyunga, Antoinette A.(Kenya Wildlife Service Forensics and Genetics Laboratory)
Spotted fever group rickettsioses are a group of tick-borne zoonotic diseases caused by intracellular bacteria of the genus Rickettsia. The diseases are widely reported amongst international travellers returning from most sub-Saharan Africa with fever, yet their importance in local populations largely remains unknown. Although this has started to change and recently there have been increasing reports of the diseases in livestock, ticks and humans in Kenya, they have not been investigated in wildlife. We examined the presence, prevalence and species of Rickettsia present in wildlife in two regions of Kenya with a unique human-wildlife-livestock interface. For this purpose, 79 wild animals in Laikipia County and 73 in Maasai Mara National Reserve were sampled. DNA extracted from blood was tested using the polymerase chain reaction (PCR) to amplify the intergenic spacer rpmE-tRNAfMet and the citrate synthase-encoding gene gltA. Rickettsial DNA was detected in 2 of the 79 (2.5%) animals in Laikipia and 4 of the 73 (5.5%) in Maasai Mara. The PCR-positive amplicons of the gltA gene were sequenced to determine the detected Rickettsia species. This revealed Rickettsia sibirica in a Topi (Damaliscus lunatus ssp. jimela). This is the first report of spotted fever group rickettsioses in wildlife and the first to report R. sibirica in Kenya. The finding demonstrates the potential role of wild animals in the circulation of the diseases.
Показать больше [+] Меньше [-]Wildlife-livestock interactions and risk areas for cross-species spread of bovine tuberculosis Полный текст
2017
Meunier, Natascha V.(Royal Veterinary College Department of Pathology and Pathogen Biology ,London School of Hygiene and Tropical Medicine Faculty of Epidemiology and Population Health) | Sebulime, Peregrine(London School of Hygiene and Tropical Medicine Faculty of Epidemiology and Population Health) | White, Richard G.(London School of Hygiene and Tropical Medicine Faculty of Epidemiology and Population Health) | Kock, Richard(Royal Veterinary College Department of Pathology and Pathogen Biology)
The transmission of diseases between livestock and wildlife can be a hindrance to effective disease control. Maintenance hosts and contact rates should be explored to further understand the transmission dynamics at the wildlife-livestock interface. Bovine tuberculosis (BTB) has been shown to have wildlife maintenance hosts and has been confirmed as present in the African buffalo (Syncerus caffer) in the Queen Elizabeth National Park (QENP) in Uganda since the 1960s. The first aim of this study was to explore the spatio-temporal spread of cattle illegally grazing within the QENP recorded by the Uganda Wildlife Authority (UWA) rangers in a wildlife crime database. Secondly, we aimed to quantify wildlife-livestock interactions and cattle movements, on the border of QENP, using a longitudinal questionnaire completed by 30 livestock owners. From this database, 426 cattle sightings were recorded within QENP in 8 years. Thirteen (3.1%) of these came within a 300 m-4 week space-time window of a buffalo herd, using the recorded GPS data. Livestock owners reported an average of 1.04 (95% CI 0.97-1.11) sightings of Uganda kob, waterbuck, buffalo or warthog per day over a 3-month period, with a rate of 0.22 (95% CI 0.20-0.25) sightings of buffalo per farmer per day. Reports placed 85.3% of the ungulate sightings and 88.0% of the buffalo sightings as further than 50 m away. Ungulate sightings were more likely to be closer to cattle at the homestead (OR 2.0, 95% CI 1.1-3.6) compared with the grazing area. Each cattle herd mixed with an average of five other cattle herds at both the communal grazing and watering points on a daily basis. Although wildlife and cattle regularly shared grazing and watering areas, they seldom came into contact close enough for aerosol transmission. Between species infection transmission is therefore likely to be by indirect or non-respiratory routes, which is suspected to be an infrequent mechanism of transmission of BTB. Occasional cross-species spillover of infection is possible, and the interaction of multiple wildlife species needs further investigation. Controlling the interface between wildlife and cattle in a situation where eradication is not being considered may have little impact on BTB disease control in cattle.
Показать больше [+] Меньше [-]B-cell epitopes of African horse sickness virus serotype 4 recognised by immune horse sera Полный текст
2017
Mathebula, Evans M.(Onderstepoort Veterinary Institute Agricultural Research Council ,University of Pretoria Department of Veterinary Tropical Diseases) | Faber, Frederika E.(Onderstepoort Veterinary Institute Agricultural Research Council) | van Wyngaardt, Wouter(Onderstepoort Veterinary Institute Agricultural Research Council) | van Schalkwyk, Antoinette(Onderstepoort Veterinary Institute Agricultural Research Council) | Pretorius, Alri(Onderstepoort Veterinary Institute Agricultural Research Council ,University of Pretoria Department of Veterinary Tropical Diseases) | Fehrsen, Jeanni(Onderstepoort Veterinary Institute Agricultural Research Council ,University of Pretoria Department of Veterinary Tropical Diseases)
Identifying antigenic proteins and mapping their epitopes is important for the development of diagnostic reagents and recombinant vaccines. B-cell epitopes of African horse sickness virus (AHSV) have previously been mapped on VP2, VP5, VP7 and NS1, using mouse, rabbit and chicken monoclonal antibodies. A comprehensive study of the humoral immune response of five vaccinated horses to AHSV-4 antigenic peptides was undertaken. A fragmented-genome phage display library expressing a repertoire of AHSV-4 peptides spanning the entire genome was constructed. The library was affinity selected for binders on immobilised polyclonal immunoglobulin G (IgG) isolated from horse sera collected pre- and post-immunisation with an attenuated AHSV-4 monovalent vaccine. The DNA inserts of binding phages were sequenced with Illumina high-throughput sequencing. The data were normalised using pre-immune IgG-selected sequences. More sequences mapped to the genes coding for NS3, VP6 and VP5 than to the other genes. However, VP2 and VP5 each had more antigenic regions than each of the other proteins. This study identified a number of epitopes to which the horse's humoral immune system responds during immunisation with AHSV-4.
Показать больше [+] Меньше [-]Epidemiology and effect of gastrointestinal nematodes on dairy goats in Argentina Полный текст
2017
Suarez, Victor H.(Centro de Investigaciones Agropecuarias Instituto Nacional de Tecnología Agropecuaria) | Martínez, Gabriela M.(Centro de Investigaciones Agropecuarias Instituto Nacional de Tecnología Agropecuaria) | Viñabal, Alberto E.(Centro de Investigaciones Agropecuarias Instituto Nacional de Tecnología Agropecuaria) | Alfaro, José R.(Centro de Investigaciones Agropecuarias Instituto Nacional de Tecnología Agropecuaria)
The aim of this work was to study the epidemiology and harmful effects of gastrointestinal nematodes (GINs) on dairy goats maintained in an intensive system. Two groups of goats were studied: untreated group (UG) (subdivided into UGjun goats that kidded in June, and UGjul goats that kidded in July) and treated group (TG) (with no subgroups, treated with monepantel: 3.75 mg/kg, orally, monthly). Eggs per gram (epg) in faeces were counted, faecal culture was performed to differentiate nematode genera and milk production was measured. Differences between groups were compared using least squares means analysis of variance (milk production and milking period length) and Kruskal-Wallis test (faecal egg counts). Nematode infection was moderate, with Haemonchus and Trichostrongylus being the dominant genera; the faecal egg counts reached the level of 2000 only once throughout the study. Goats that kidded in June had higher egg count after parturition (UGjun = 1564 epg), with significant differences (p < 0.04) from those that still had not kidded (UGjul = 962 epg). Over the entire trial period, the mean total milk production of TG (399.5 L ± 34.0 L) was significantly higher (p < 0.05) than that of UG (281.6 L ± 37.5 L), representing an increase of 41.8% in total milk yield. The results of this study show a post-partum peak in egg count and a negative effect of GINs on milk yield, even with moderate infections.
Показать больше [+] Меньше [-]Prevalence and renal pathology of pathogenic Leptospira spp. in wildlife in Abeokuta, Ogun State, Nigeria Полный текст
2017
Ajayi, Olusola L.(Federal University of Agriculture Department of Veterinary Pathology) | Antia, Richard E.(University of Ibadan Department of Veterinary Pathology) | Ojo, Olufemi E.(Federal University of Agriculture Department of Veterinary Microbiology and Parasitology) | Awoyomi, Olajoju J.(Federal University of Agriculture Department of Veterinary Public health and Reproduction) | Oyinlola, Latifa A.(Federal University of Agriculture Department of Food Science and Technology) | Ojebiyi, Oluwabusola G.(Federal University of Agriculture Department of Veterinary Pathology)
There is paucity of information on the prevalence of leptospirosis in wildlife in Nigeria. This study investigated the prevalence and renal pathology of leptospirosis in wild animals in Southwest Nigeria. One hundred and five kidney samples were examined from 10 different wildlife species (antelope) greater cane rat (GCR), hare, African giant rat (AGR), tree hyrax, civet cat, monitor lizard, python, bushbuck and partridge) using a combination of Ellinghausen McCullough Johnson Harris (EMJH) medium, microscopic agglutination test (MAT), Warthin-Starry silver stain (WSss) and immunohistochemistry. Chi-square test was used with confidence level set at 0.05 to ascertain associations between positive cases and sex and species. Eighty-two (78.1%) samples were culturally positive, while 67.7% (63/93), 57.0% (16/28) and 66.7% (8/12) were WSss, MAT and immunohistochemically positive, respectively. Interstitial nephritis (41.0%) and tubular nephrosis (81.0%) were the most prominent histopathological changes. Pathogenic Leptospira organisms were highest in GCR (32.1%) and antelope (14.3%). Serovars hardjo (11.54%), bratislava (3.9%), canicola (3.9%), icterohaemorrhagiae (15.4%), pomona (7.14%) gripptotyphosa (19.2%) and undetermined isolates were also detected in other animals. The result showed high prevalence of Leptospira infection in the wild and the possibility of domestic animals and humans contracting the disease. This study is the first documentation of evidence of pathogenic Leptospira species in wildlife in Nigeria.
Показать больше [+] Меньше [-]Identification and phylogenetic analysis of contagious ecthyma virus from camels (Camelus dromedarius) in Iran Полный текст
2017
Oryan, Ahmad(Shiraz University Department of Pathobiology) | Mosadeghhesari, Mahboobe(Shiraz University Department of Pathobiology) | Zibaee, Saeed(Razi Vaccine and Serum Research Institute) | Mohammadi, Ali(Shiraz University Department of Pathobiology)
Contagious ecthyma is a highly contagious disease affecting domestic and wild ruminants such as sheep, goats and camels. The identification and characterisation of a parapoxvirus (PPV) infecting camels is described here. The virus was detected in dromedary camels (Camelus dromedarius) from Kerman and Shiraz in Iran. PPV-specific amplification by polymerase chain reaction (PCR) further confirmed that the disease was associated with PPV infection. Phylogenetic analysis of ORF011 (B2L) gene sequences showed 99.79% and 82.13% similarity of the PPV identified in this study with the Jodhpur isolate and the bovine papular stomatitis virus (BPSV) isolates (CE41), respectively. Moreover, phylogenetic analysis of the ORF045 gene indicated that the Shiraz sample was in all probability closely related to VR634 and to F00.120R and PCPV776. In conclusion, the results suggest that camel PPV (CPPV) is a likely cause of contagious ecthyma in dromedary camels in Iran.
Показать больше [+] Меньше [-]The involvement of the hypothalamo-pituitary-adrenocortical axis in stress physiology and its significance in the assessment of animal welfare in cattle Полный текст
2017
Brown, Emma J.(University of KwaZulu-Natal School of Life Sciences) | Vosloo, Andre(University of KwaZulu-Natal School of Life Sciences)
The intensification of cattle production has raised concern for animal welfare due to the stress that is associated with farming practices. The welfare of an animal is determined by the animal's ability to cope with or adapt to its continuously changing environment and the biological cost that is associated with this adaptation and maintenance. Stressors arise from various psychological, physiological and physical aspects of farming practices due to management and human-cattle interactions. Measuring the activity of the hypothalamo-pituitary-adrenocortical (HPA) axis with plasma cortisol levels is a useful method for determining the effects of stress on animals as it is stimulated at the onset of a perceived stress. The activation of the HPA axis affects various target tissues or systems and can result in suppression of the immune system, increased susceptibility to disease and adverse effects on reproductive success in prenatal and neonatal calves. Although some levels of stress associated with farming practices are unavoidable, improvements in farming methods need to be implemented in order to maintain or increase the efficiency of cattle production in a way that does not compromise the welfare of the animal.
Показать больше [+] Меньше [-]Spatiotemporal patterns of clinical bovine dermatophilosis in Zimbabwe 1995-2014 Полный текст
2017
Ndhlovu, Felistas | Ndhlovu, Daud N.(University of Zimbabwe Department of Clinical Veterinary Studies) | Chikerema, Sylvester M.(University of Zimbabwe Department of Clinical Veterinary Studies) | Masocha, Mhosisi(University of Zimbabwe Department of Geography and Environmental Science) | Nyagura, Mudavanhu(University of Zimbabwe Department of Pre-Clinical Veterinary Studies) | Pfukenyi, Davies M.(University of Zimbabwe Department of Clinical Veterinary Studies)
A retrospective study of clinical bovine dermatophilosis outbreaks and cases for the period 1995-2014 was conducted, using data obtained from the Division of Veterinary Services (DVS). A total of 3856 outbreaks and 26 659 cases of dermatophilosis were reported countrywide during this period. The post rainy season accounted for 37.9% of the outbreaks followed by the rainy season (26.7%), cold dry season (22.1%) and the hot dry season (13.2%). A retrospective space-time scan statistic in SaTScan™ was used to detect clusters. From this study, it was evident that dermatophilosis was spreading from the north-west of Zimbabwe through the central to the north-east during the period 2010-2014. Five clusters were identified mainly in the central and north-western regions of Zimbabwe. The primary cluster was centred at Ungwe, Gokwe district in Midlands; the second, third, fourth and fifth likely clusters were centred at Bonga (Mashonaland Central), ARDA (Mashonaland West), Nsenga (Matabeleland North) and Zanda in Gokwe, respectively. The findings of this study suggest the continued spread of dermatophilosis across the country; as such the Department of Livestock and Veterinary Services are advised to develop measures aimed at managing this spread such as dipping, quarantine, movement control and raising farmer awareness.
Показать больше [+] Меньше [-]Phylogenetic analysis of a partial L1 gene from bovine papillomavirus type 1 isolated from naturally occurring papilloma cases in the northwestern region of Turkey Полный текст
2017
Timurkan, M. Ozkan(Atatürk University Department of Virology) | Alcigir, M. Eray(Ankara University Department of Pathology)
This study was aimed at the molecular characterisation of bovine papillomavirus type 1 (BPV-1) isolated from papilloma cases in the northwestern region of Turkey. BPV-1 is a widely occurring oncogenic virus in cattle and is associated with benign epithelial neoplasia which causes significant economic losses in dairy and beef cattle because of treatment costs. In this study, 29 suspected papilloma specimens were collected from cattle in northwestern Turkey. These samples underwent molecular characterisation via the polymerase chain reaction (PCR) and sequencing analysis as well as macroscopic and histopathological examination. The histopathological examinations confirmed papilloma as the main lesion type in the specimens. Of the 29 papilloma-like tissue samples that were collected, 11 (i.e. 37.93%) were detected as positive and determined as containing BPV-1 (11 of 11, 100%). Using a partial sequence for the L1 gene acquired from GenBank, phylogenetic analysis confirmed the presence of BPV-1 and revealed that the infection might have originated in cross bred domestic and imported cattle. This study provides potentially useful information on the origin and spread of this disease. Its results can potentially aid in the development of appropriate control measures and therapeutic or vaccination strategies against the BPV-1 strain of bovine papillomatosis.
Показать больше [+] Меньше [-]Geigerin-induced cytotoxicity in a murine myoblast cell line (C2C12) Полный текст
2017
Botha, Christo J.(University of Pretoria Department of Paraclinical Sciences) | Clift, Sarah J.(University of Pretoria Department of Paraclinical Sciences) | Ferreira, Gezina C.H.(University of Pretoria Department of Paraclinical Sciences) | Masango, Mxolisi G.(Agricultural Research Council-Onderstepoort Veterinary Institute Food, Feed and Veterinary Public Health)
Geigeria poisoning in sheep, locally known as 'vermeersiekte', is an economically important plant poisoning in southern Africa. The toxic principles contained by the toxic plants are believed to be several sesquiterpene lactones, such as geigerin, vermeeric acid and vermeerin, which cause striated muscle lesions in small stock. Because of ethical issues surrounding the use of live animals in toxicity studies, there is currently a dire need to establish an in vitro model that can be used to replace traditional animal experimentation. The objective of this study was to determine the cytotoxicity of geigerin in a murine myoblast cell line (C2C12) using methyl-thiazol-tetrazolium (MTT) and lactate dehydrogenase (LDH) assays, annexin V and propidium iodide (PI) flow cytometry and transmission electron microscopy (TEM). Mouse myoblasts were exposed to 2.0 mM, 2.5 mM and 5.0 mM geigerin for 24, 48 and 72 h. A concentration-dependent cytotoxic response was observed. Apoptosis was detected by means of annexin V flow cytometry during the first 24 h and apoptotic bodies were also visible on TEM. According to the LDH and PI flow cytometry results, myoblast cell membranes were not injured. We concluded that the murine myoblast cell line (C2C12) is a suitable model for future studies planned to evaluate the cytotoxicity of other and combinations of sesquiterpene lactones, with and without metabolic activation, implicated in 'vermeersiekte' and to elucidate the subcellular effects of these myotoxins on cultured myoblasts.
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