خيارات البحث
النتائج 261 - 270 من 452
Ticks of four-toed elephant shrews and Southern African hedgehogs
2011
Ivan G. Horak | Shaun Welman | Stacey L. Hallam | Heike Lutermann | Nomakwezi Mzilikazi
Several studies on ticks infesting small mammals, including elephant shrews, have been conducted in South Africa; however, these studies have included only a single four-toed elephant shrew and no hedgehogs. This study thus aimed to identify and quantify the ixodid ticks infesting four-toed elephant shrews and Southern African hedgehogs. Four-toed elephant shrews (Petrodromus tetradactylus) were trapped in dense shrub undergrowth in a nature reserve in north-eastern KwaZulu-Natal. They were separately housed, first in cages and later in glass terraria fitted with wire-mesh bases to allow detached ticks to fall through for collection. Southern African hedgehogs (Atelerix frontalis) were hand caught on a farm in the eastern region of the Northern Cape Province and all visible ticks were collected by means of tweezers while the animals were anaesthetised. The ticks from each animal were preserved separately in 70% ethanol for later identification and counting. The immature stages of five ixodid tick species were collected from the elephant shrews, of which Rhipicephalus muehlensi was the most common. It has not been recorded previously on any species of elephant shrew. Three ixodid tick species were collected from the hedgehogs. Large numbers of adult Haemaphysalis colesbergensis, which has not been encountered previously on hedgehogs, were collected from these animals. Four-toed elephant shrews are good hosts of the larvae and nymphs of R. muehlensi, and Southern African hedgehogs are good hosts of adult H. colesbergensis.
اظهر المزيد [+] اقل [-]Ticks infesting cattle in Central Equatoria region of South Sudan
2011
Wani L. Marcellino | Ibrahim I. Julla | Diaeldin A. Salih | Abdel R.M. El Hussein
Ticks infesting cattle represent a serious problem for improvement of cattle productivity in South Sudan. There has been limited information on ticks and tick-borne diseases in southern Sudan. This study was initiated to update the current distribution of ticks infesting cattle in the Central Equatoria region of South Sudan. The surveys for the present study were conducted at various cattle camps in Juba, Mangalla and Terekeka between December 2004 and June 2005. A total of 2322 ticks were collected from the bodies of 88 randomly selected cattle. Ticks were preserved in 70% ethanol for later identification. Seven ixodid tick species were found to infest cattle in Juba whilst six species were recorded in Mangalla and only four species in Terekeka. Amblyomma variegatum was the most common and widely distributed species found on cattle across all the study locations. Amblyomma lepidum was not found during this study. Based on these findings, it would be advisable to preempt the situation and institute containment procedures before possible East Coast fever outbreaks occur.
اظهر المزيد [+] اقل [-]The dynamics of questing ticks collected for 164 consecutive months off the vegetation of two landscape zones in the Kruger National Park (1988-2002). Part I. Total ticks, Amblyomma hebraeum and Rhipicephalus decoloratus
2011
Horak, Ivan G(University of Pretoria Department of Veterinary Tropical Diseases) | Gallivan, Gordon J(Ottawa) | Spickett, Arthur M(Onderstepoort Veterinary Institute Parasites, Vectors & Vector-borne Diseases Programme)
The dynamics of questing ticks collected for 164 consecutive months off the vegetation of two landscape zones in the Kruger National Park (1988-2002). Part III. The less commonly collected species
2011
Gallivan, Gordon J(Ottawa) | Spickett, Andrea(Onderstepoort Veterinary Institute Parasites, Vectors & Vector-borne Diseases Programme) | Heyne, Heloise(Onderstepoort Veterinary Institute Parasites, Vectors & Vector-borne Diseases Programme) | Spickett, Arthur M(Onderstepoort Veterinary Institute Parasites, Vectors & Vector-borne Diseases Programme) | Horak, Ivan G(University of Pretoria Department of Veterinary Tropical Diseases)
Despite many studies regarding tick ecology, limited information on long-term changes in tick populations exist. This study assessed the long-term population dynamics of the less frequently collected questing ixodid ticks in the Kruger National Park (KNP). From 1988 to 2002, monthly dragging of the vegetation was performed in three habitats (grassland, woodland and gully) at two sites in the KNP (Nhlowa Road, Landscape Zone 17, and Skukuza, Landscape Zone 4). Amblyomma marmoreum and Rhipicephalus evertsi evertsi were collected as larvae most commonly. Most A. marmoreum larvae were collected at Skukuza and numbers peaked from March to July. More R. evertsi evertsi larvae were collected at Nhlowa Road and numbers peaked in summer and in winter, while at Skukuza there was a single peak in spring. Haemaphysalis elliptica, Rhipicephalus simus and Rhipicephalus turanicus were collected as adults most commonly. More Ha. elliptica and R. turanicus were collected at Nhlowa Road than at Skukuza, while R. simus numbers from the two sites were approximately equal. Ha. elliptica were collected most often between February and June, and R. simus and R. turanicus during February and March. All three species were collected more frequently in gullies than in grassland or woodland. Their numbers increased in 1994/1995 following an eruption of rodents, the preferred hosts of the immature stages. The different host-seeking strategies of ticks largely determine the development stage at which they are likely to be collected during vegetation dragging and reflect a complex interaction between ticks, their hosts and the environment
اظهر المزيد [+] اقل [-]Rumen protozoa in South African sheep with a summary of the worldwide distribution of sheep protozoa
2011
Booyse, Dirk(University of Pretoria Department of Anatomy and Physiology) | Dehority, Burk A.(Ohio State University Department of Animal Sciences)
Protozoa species were identified in rumen contents of four domestic sheep (Ovis aries) from South Africa. All animals were fed a forage diet which consisted of 50% lucerne and 50% teff hay. Ten new host records were identified, bringing the total number of species and forms observed in sheep in South Africa to 30. The occurrence and geographic distribution of ciliate protozoa in both domestic and wild sheep from around the world are summarised. It was found that 15 genera and 131 species occur in domestic sheep globally.
اظهر المزيد [+] اقل [-]Ixodid ticks, fleas and lice infesting dogs and cats in Hawassa, southern Ethiopia
2011
Kumsa, Bersissa E.(Addis Ababa University Department of Parasitology ,University of Padova Department of Experimental Sciences) | Mekonnen, Shewit(Addis Ababa University Department of Parasitology)
This study investigated the prevalence, risk factors and species composition of ticks, fleas and lice infesting dogs and cats in and around Hawassa in southern Ethiopia. In total, 200 dogs and 100 cats were examined from November 2008 to April 2009. Of the dogs and cats examined, 99.5%and 91.5%, respectively, were infested with one or more species of ticks, fleas or lice. The overall prevalence was higher in dogs than in cats. A total of six different species of ectoparasites were collected and identified from dogs, but only three species from cats. Ctenocephalides felis was the predominant species amongst the animals, with a prevalence of 82.9% on dogs and 67% on cats. Other prevalent species on dogs included Ctenocephalides canis (73.8%), Heterodoxus spiniger (4%), nymphs of Amblyomma spp. (3.5%), Pulex irritans (2.5%) and Haemaphysalis leachi (0.5%). C. canis (18%) and P. irritans (6%) were also found on cats. More female than male fleas and lice were observed. The study revealed that the prevalence of fleas, ticks and lice on dogs was not significantly different between male and female animals or between young and adult dogs. However, the prevalence of these ectoparasites was significantly higher in female than in male and in adult than in young cats. The study showed that the prevalence of ectoparasites on both dogs and cats was significantly higher on animals with flea allergy dermatitis (FAD) than those without FAD, and on animals with lesions on their skin compared with those without lesions.
اظهر المزيد [+] اقل [-]Ticks on pastures and on two breeds of cattle in the Eastern Cape province, South Africa
2011
Nyangiwe, Nkululeko(Döhne Agricultural Development Institute) | Goni, Sindisile(Döhne Agricultural Development Institute) | Hervé-Claude, Louis P.(University of Veterinary Medicine of Hannover Institute of Biometry) | Ruddat, Inga(University of Veterinary Medicine of Hannover Institute of Biometry) | Horak, Ivan G.(University of Pretoria Department of Veterinary Tropical Diseases ,University of the Free State Department of Zoology and Entomology)
Many studies on the population dynamics of questing ticks on pastures and of parasitic ticks on cattle have been conducted. Few, however, have attempted to link the two in a single study. This study aimed to assess the population dynamics of questing ixodid ticks on pastures and of adult ticks on two breeds of cattle with different levels of susceptibility to tick infestation on the same pastures. Between January 2005 and December 2009 questing ixodid ticks were collected monthly from natural pastures at the Döhne Agricultural Development Institute and at the adjacent Campagna Production System in the Amahlathi District, Eastern Cape province, South Africa. Between February 2007 and January 2010 adult ticks were collected monthly from Bonsmara and Nguni cattle grazing these pastures. Ten tick species were collected from the pastures and 12 from the cattle. Significantly more questing larvae of Rhipicephalus appendiculatus, Rhipicephalus decoloratus, Rhipicephalus evertsi evertsi and Rhipicephalus microplus were recovered from the pastures grazed by Bonsmara cattle than from those grazed by Nguni cattle (p <0.05). Significantly more adult Hyalomma rufipes, Rhipicephalus follis, R. appendiculatus, R. decoloratus, R. evertsi evertsi and R. microplus were collected from the Bonsmara cattle than from the Nguni cattle (p < 0.05). The study showed that Nguni cattle are less susceptible to tick infestation than are Bonsmara cattle and fewer questing ticks are collected from pastures grazed by Nguni cattle than by Bonsmara cattle.
اظهر المزيد [+] اقل [-]Use of real-time quantitative reverse transcription polymerase chain reaction for the detection of African horse sickness virus replication in Culicoides imicola
2011
Scheffer, Elisabeth G.(University of Pretoria Equine Research Centre ,Freie Universität Berlin Institut für Virologie) | Venter, Gert J.(ARC-Onderstepoort Veterinary Institute ,University of Pretoria Department of Veterinary Tropical Diseases) | Joone, Christopher(University of Pretoria Equine Research Centre) | Osterrieder, Nikolaus(Freie Universität Berlin Institut für Virologie) | Guthrie, Alan J.(University of Pretoria Equine Research Centre)
Despite its important role as vector for African horse sickness virus (AHSV), very little information is available on the dissemination of this virus in Culicoides (Avaritia) imicola Kieffer (Diptera: Ceratopogonidae). This study reports on the applicability of a real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR) to detect AHSV in dissected midges. A total of 96 midges were fed on AHSV-infected blood, after which one test group was dissected into head/thorax and abdomen segments immediately after feeding and the other only after 10 days of incubation. The majority of the midges (96%) ingested the virus successfully and there was no significant difference between the virus concentration in the heads/thoraxes and the abdomens immediately after feeding. After incubation, virus was detected in 51% of the midges and it was confined to the abdomen in the majority of these. The fact that virus was detected only in the heads/thoraxes of four Culicoides midges after incubation suggests the presence of a mesenteronal escape barrier. Replication in the salivary glands was not shown. An increase of the mean virus concentration in the abdomen after incubation indicates localised viral replication. The real-time RT-qPCR is recommended for further studies investigating the replication and dissemination of AHSV in Culicoides midges.
اظهر المزيد [+] اقل [-]The virulence of Brucella abortus isolated from cattle in Korea
2011
Lim, J.J., Gyeongsang National University, Jinju, Republic of Korea | Kim, J.H., Northern Branch, Gyeongbuk Veterinary Service Laboratory, Andong, Republic of Korea | Kim, D.H., Gyeongsang National University, Jinju, Republic of Korea | Lee, J.J., Gyeongsang National University, Jinju, Republic of Korea | Kim, D.G., Gyeongsang National University, Jinju, Republic of Korea | Jun, M.H., Chungnam National University, Daejeon, Republic of Korea | Kim, S.H., Chungnam National University, Daejeon, Republic of Korea | Chang, H.H., Gyeongsang National University, Jinju, Republic of Korea | Lee, H.J., Gyeongsang National University, Jinju, Republic of Korea | Min, W.G., Gyeongsang National University, Jinju, Republic of Korea | Kim, S., Gyeongsang National University, Jinju, Republic of Korea
In this study, we isolated 12 of Brucella (B.) spp. from cattle, which have been positive in Rose Bangal test and tube agglutination test in Gyeongbuk province in 2009. According to AMOS PCR analysis, isolated 12 strains were identified as B. abortus. Murine derived macrophage, RAW 264.7 cells, were infected with isolated 12 strains or reference strain (B. abortus 544), and bacterial internalization were characterized. According to these results, we divided the isolated strains into the following three groups: class Ⅰ, lower internalization than that of B. abortus 544; class Ⅱ, similar internalization to that of that of B. abortus 544; class Ⅲ, higher internalization than that of B. abortus 544 within RAW 264.7 cells. Furthermore, intracellular growth, bacterial adherent assay, LAMP-1 colocalization, virulence in mice and surface protein pattern were characterized. From these results, representative strains of class Ⅲ showed lower LAMP-1 colocalization, higher adherent efficiency, higher virulence in mice than those of B. abortus 544, and showed different pattern of surface proteins. These results suggest that B. abortus field strains, isolated from cattle in Korea, possess various virulence properties and higher internalization ability of field strain may have an important role for its virulence expression.
اظهر المزيد [+] اقل [-]Isolation and Antimicrobial Susceptibility of Microorganisms from Milk Samples of Jindo Dogs (Canis familiaris var. jindo)
2011
Lee, J.D., Jeollanamdo Livestock Sanitation Office, Gangjin, Republic of Korea | Lee, Y.K., Chonnam National University, Gwangju, Republic of Korea | O, S.I., Jindo Dog Research and Testing Center, Jindo, Republic of Korea | Jung, J.Y., Jeollanamdo Livestock Sanitation Office, Gangjin, Republic of Korea | Son, C.H., Chonnam National University, Gwangju, Republic of Korea | Shin, S.S., Chonnam National University, Gwangju, Republic of Korea | Oh, K.S., Chonnam National University, Gwangju, Republic of Korea | Hur, T.Y., National Institute of Animal Science, RDA, Cheonan, Republic of Korea | Suh, G.H., Chonnam National University, Gwangju, Republic of Korea
Lack of hygiene and puerperal mastitis are common causes of bacterial diseases in nursing neonates. The aim of this study was to isolate microorganisms from milk samples of healthy female Jindo dogs with suckling puppies and to investigate antimicrobial susceptibility against the isolated bacteria. Milk samples were collected from 120 udders of 12 lactating Jindo dogs that were 2~4 years old without any clinical diseases including mastitis. Bacteria were isolated from 64 milk samples (53.3%), either singly (76.6%) or in combination (23.4%). Staphylococcus (S.) spp. was the most common microorganisms (74.7%) isolated from canine milk, followed by Haemophillus spp. (10.9%), Streptococcus spp. (9.6%), Gardnerella spp. (2.4%) and Moraxella spp. (2.4%). The most frequently isolated organism was S. warneri (31.3%). Antimicrobial susceptibility of these bacteria was tested with 17 antimicrobial agents by Kirbyand Bauer standardized disc diffusion method. Results indicated that bacteria isolated from healthy canine milk were mostly susceptible to amoxicillin-clavulanic acid, cephalothin and ceftiofur, but were resistant to erythromycin, neomycin and tetracycline.
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