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Kurt Pfister

Publications and source records attributed to Kurt Pfister.

12 recordsLinked to original sources

Sero-prevalence and risk indicators for canine ehrlichiosis in three rural areas of Brazil.

Ehrlichia canis has a worldwide geographic distribution, occurring particularly in tropical and subtropical areas. In Brazil, the main vector in urban areas is believed to be the brown dog tick Rhipicephalus sanguineus, but little is known about the occurrence, transmission and other epidemiological aspects of canine ehrlichiosis in rural areas, where Amblyomma ticks are found more frequently than R. sanguineus. A sero-prevalence study of canine ehrlichiosis was carried out in three distinct rural regions of the State of Minas Gerais, Brazil. Serum samples were collected from 226 dogs living on farms in Lavras (n=85), Belo Horizonte (n=45), and Nanuque (n=96) and were analyzed by an indirect fluorescent antibody test for the detection of anti-Ehrlichia canis antibodies. Age, breed, sex, presence of ticks and packed cell volume were also recorded. There were 65.6% positive dogs in Nanuque, 37.8% in Belo Horizonte, and 24.7% in Lavras. Animals living in Nanuque were 4.6 times more likely to be serologically positive than dogs living in the other two regions and antibody titres were considerable higher in this area. Male dogs, dogs >5 years of age, those infested with ticks, and mongrels all showed higher rates of positivity. The results point to the importance of canine ehrlichiosis in rural areas and indicate the need for further studies on natural transmission and maintenance of the disease.

Animals↗

Survey on the subject of equine Lyme borreliosis.

According to the results of a questionnaire on equine Lyme borreliosis addressing veterinarians in Germany, the existence of the disease was confirmed by more than half of the 118 participants. Practitioners who regarded Borrelia burgdorferi as a pathogen of horses seemed to be more sensitized in terms of the number of annually diagnosed cases as well as the frequency of occurrence of tick infestation with equine patients or prophylactic treatments against ectoparasites by horse owners. Chronically poor performance and diverse orthopaedic problems were the clinical symptoms most often leading to a Lyme borreliosis suspicion. The tentative diagnoses were predominantly confirmed by serology. Antibiotics (and anti-inflammatory agents) were mainly used for therapy. Whereas horse owners repeatedly asked for examination of their horses, and some veterinarians asserted equine Lyme borreliosis to be an underestimated problem in the horse population, others stated the disease was often enough misdiagnosed.

Animals↗

[Mites as a cause of zoonoses in human beings].

Different mite species occurring in animals may infest humans temporarily. Such agents should be considered a possible cause of erythemateous and sometimes pruritic skin reactions of unclear origin. Pseudoscabies is a common problem in occupationally exposed humans, e.g. farmers, veterinarians or pet owners. Those selflimiting dermatoses may often be misdiagnosed. Several species including Sarcoptes scabiei, Notoedres cati, Cheyletiella spp., Dermanyssus gallinae, Ornithonyssus bacoti, Ophionyssus natricis and Neotrombicula autumnalis may infest human skin, causing symptoms.

Animals↗

First molecular detection of Babesia vogeli in dogs from Brazil.

The present work describes the detection and first molecular characterization of Babesia vogeli in dogs, naturally infected in Brazil and even in South America. Microscopic examination of Giemsa-stained peripheral blood smears collected from dogs originating from four different locations in Brazil revealed the presence of large Babesia merozoites and trophozoites (>2.5 microm). DNA was extracted from infected blood samples and PCR amplifications of the 18S rDNA were carried out. As a reference, DNA from an isolate of B. vogeli originated from Egypt was used. PCR products were purified and sequenced. The DNA sequences demonstrated 100% identity among the Brazilian isolates. Comparisons with the 18S rDNA sequence of the B. vogeli isolate from Egypt and with other B. vogeli sequences from Spain, France, Japan, Australia and South Africa confirmed the affiliation of all Brazilian isolates to the species B. vogeli.

Animals↗

Amplification of ribosomal DNA of Anoplocephalidae: Anoplocephala perfoliata diagnosis by PCR as a possible alternative to coprological methods.

The diagnosis of tapeworm infections in horses relies on copro-diagnostic methods, which are time-consuming and of limited sensitivity for determination of the exact prevalence. The development of serological tests has slightly improved the detection of tapeworm infections, but more sensitive methods are still required. A polymerase chain reaction (PCR)-based approach may constitute a valuable tool to improve tapeworm diagnosis. Nuclear ribosomal DNA (rDNA) is a useful target for species and/or strain markers. Partial 18S, the internal transcribed spacer 1 (ITS-1), the 5.8S, the internal transcribed spacer 2 (ITS-2), and partial 28S rDNA of the equine tapeworms Anoplocephala perfoliata and Anoplocephaloides mamillana were amplified and sequenced. The lengths and GC contents of the regions sequenced were 2087-2091bp and 49.35-49.69% for A. perfoliata, and 2110-2119bp and 49.15-49.32% for A. mamillana, respectively. Sequence alignment and comparison of both taxa showed 79.3-80.2% identity. The lowest identities were found in the ITS regions with 39.9-43.5% for the ITS-1 and 59.5-61.2% for the ITS-2. No matches of the ITS-2 of A. perfoliata and A. mamillana were found with other species by BLAST search. For this reason, ITS-2 sequences seemed appropriate as accurate species markers and A. perfoliata ITS-2 primers were developed. The ITS-2 PCR enabled the detection of genomic DNA as low as 0.5 pgs. First efforts on the practical application of the PCR-based approach were made. A 6-mg fragment of a tapeworm proglottid was detected in 0.5 and 1g of faeces.

Animals↗

[Occurrence of a house-infesting tropical rat mite (Ornithonyssus bacoti) on murides and human beings in Munich: 3 case reports].

In Germany there is little information available about the distribution of the Tropical rat mite (Ornithonyssus bacoti) in rodents. A few case reports show that this hematophagous mite species may also cause dermatitis in man. All developmental stages are exclusively blood feeders. Three children (4, 11 and 15 years old) of a family, a 23-year-old medical student and a 17-year-old dental technician were attacked by the tropical rat mite. Prior to the consultation of our institute, the patients' conditions had been diagnosed as allergic dermatitis and treated by several antiphlogistic agents, however without success. The conclusive diagnosis of tropical rat mite dermatitis, was based on the identification of the arthropod O. bacoti in the flats of the patients (husbandry of gerbils, etc.) and in the dental practice. The diagnosis of rat mite dermatitis requires the detection of the parasite, which is more likely to be found in the environment of its host than on the host's skin itself.

Adolescent↗

PCR detection and serological evidence of granulocytic ehrlichial infection in roe deer (Capreolus capreolus) and chamois (Rupicapra rupicapra).

The role of wild mammals, such as roe deer (Capreolus capreolus) and chamois (Rupicapra rupicapra), in the epidemiology of granulocytic ehrlichiae in Switzerland was investigated. We tested blood samples for Ehrlichia phagocytophila genogroup 16S rRNA gene sequences by PCR and for immunoglobulin G antibodies against granulocytic ehrlichiae by indirect fluorescent-antibody assay (IFA). Overall means of 60.9% of 133 roe deer serum samples and 28.2% of 39 chamois serum samples were seroreactive by IFA. PCR results were positive for 18.4% of 103 roe deer serum samples as well. None of the 24 chamois blood samples tested were positive by PCR. Partial 16S rRNA gene and groESL heat shock operon sequences of three roe deer samples tested showed strong degrees of homology (> or =99.7 and > or =98.6%, respectively) with the sequences of granulocytic ehrlichiae isolated from humans. These results confirm that chamois, and particularly roe deer, are commonly infected with granulocytic ehrlichiae and provide evidence that these wild mammals are potential reservoirs for granulocytic ehrlichiae in Switzerland.

Animals↗

[Epidemiological investigations of bovine Chorioptes mange in Germany].

Chorioptic mange in cattle has long been recognised as a common external parasitosis in livestock. In order to evaluate the economic importance of Chorioptes bovis-mange, the seasonal prevalence in several types of husbandry in the states of Germany, location of clinical skin symptoms, procedure of diagnosis, influence on milk or meat production, and treatment especially in dairy farming, 1190 German large animal practicioners have been asked by questionnaires from which 367 responded. This paper gives an update on important epidemiological investigations on bovine chorioptic mange due to this inquiry. Since more than one third of the questioned veterinarians see tail mange often, it is of high importance for farm cattle. Chorioptes mange mainly occurs in dairy cattle stocks, and has especially negative effects on milk production and meat productivity. For treatment of this external parasitosis mainly macrocyclic lactons and pyrethroids are used.

Animal Husbandry↗

A study on the seasonal epidemiology of Anoplocephala spp.-infection in horses and the appropriate treatment using a praziquantel gel (Droncit 9% oral gel).

In a study on the seasonal dynamics of the gastro-intestinal nematode egg production in horses, one breeding farm also revealed a particularly high prevalence of Anoplocephala spp. infection. Consequently, this farm was chosen for analysing the seasonal pattern of the tapeworm egg excretion over a one year period in order to establish the most favourable periods for an appropriate and successful cestocidal treatment. The seasonal analysis showed a significantly higher (p < 0.05) Anoplocephala spp. egg excretion between July and October, i.e. during the second part of the grazing period. This result clearly underlines the importance of a cestocidal treatment during that period of the year. Subsequently, horses of this farm and of a second farm with a high prevalence of Anoplocephala spp. were used to evaluate the efficacy of praziquantel in a specific oral gel formulation for horses under field conditions. The efficacy of praziquantel was tested in a total of 33 horses from the two farms harbouring a coproscopically detected Anoplocephala spp. infection prior to treatment. Praziquantel (Droncit 9%, oral gel, 1 mg/kg bodyweight) was administered to the horses according to their body weight. The efficacy of the drug was evaluated ten days after treatment by a double faecal analysis. Thereby, no Anoplocephala spp. eggs were found in the faeces of 32 horses (97%). The single horse remaining positive for Anoplocephala spp. eggs did not completely swallow the anthelmintic gel and consequently, did not receive the appropriate dose of the drug.

Animals↗

[Tick infestation and the prevalence of Borrelia burgdorferi and Babesia divergens in cattle in Bavaria].

During the grazing period 2002 319 cattle from 31 farms located in 6 districts of southern Bavaria were examined for the presence of ticks in 4- to 5-week intervals, and 287 serum samples were tested for the presence of antibodies against Borrelia burgdorferi and Babesia divergens. Ticks were detected in all 31 farms with a mean prevalence of 69%. 3218 out of 3453 collected ticks were Ixodes ricinus; 139 nymphs, 19 larvae and 77 damaged adult specimens could only be determined to the Genus level (Ixodes). The seasonal pattern revealed the highest frequencies of ticks in May/June and September. The intensity of tick infestation of positive animals was generally low. 76.5% of parasitized cattle had 1-6 ticks per day of investigation. Individual cattle showed up to 250 ticks per day. The percentage of infested animals in each herd varied within the period between 0-100%. The examination of serum samples by immunofluorescence technique (IFAT) revealed positive anti-Borrelia antibody titers (> or = 1:64) for 45.6% of the animals. The within-farm seroprevalence of borreliosis ranged from 20 to 100% in 27 of the 31 farms. A significant correlation could be detected between the number of ticks/cattle and the anti-Borrelia burgdorferi IgG-titer. By contrast, there was no significant correlation between the age of the animals and anti-Borrelia serum titers. For comparative reasons, 64 IFAT-positive serum samples were tested by Western blot techniques for the presence of antibodies cross-reacting with Borrelia garinii antigen. These analyses revealed that 69% of the samples reacted positively, 28% were unclear and 3% were negative. Examinations of the 287 serum samples for the presence of anti-Babesia divergens antibodies revealed one positive animal with a titer of 1:16.

Animals↗

[Questionnaire on the incidence and control of fleas in dogs and cats presented to German small animal practices].

2590 small animal practitioners in Germany have been asked by a questionnaire from which 1694 (65.4%) replied. 1186 of these veterinarians (70%) often see ectoparasite infestation. Fleas are predominant and occur on cats (1016/60%), followed by dogs (424/25%), small mammals and birds (254/15%). Flea infestations on dogs and cats are observed throughout the year, but the prevalences are generally higher during the summer season. The results reveal that topically administered spot-on formulations is the most popular method used for flea control. The most common applied antiparasitic substances both in dogs and in cats were fipronil (535/31.6%; 690/40.7%), imidacloprid (290/17.1%; 417/24.6%) and selamectin (267/15.8%; 319/18.8%). Due to 771 (45.5%) of the answering veterinarians the animal owner himself, and according 694 (41%) respectively 229 (13.5%) of the replies the veterinarian or the veterinary technician applies the antiparasiticide onto the skin. 1457 veterinarians (86%) administer compounds against adult fleas and their developmental stages also in the animal's environment.

Animals↗