Set Bornstein

Evaluation of an enzyme-linked immunosorbent assay (ELISA) for the serological diagnosis of sarcoptic mange in swine

An enzyme-linked immunosorbent assay (ELISA) using an extract from Sarcoptes scabiei var. culpes as antigen was evaluated for its usefulness in monitoring antibodies to S. scabiei var. suis in naturally infected pigs. Five hundred and fifty-eight serum samples from certified Sarcoptes-free pigs (120 from weaned piglets, 218 from fatteners and 220 from adult sows) and 94 samples from certified Sarcoptes-infected pigs (35 from weaned piglets, 45 from fatteners and 14 from adult sows) were examined. The cut-off optical density (OD) values, considered to reflect the presence of antibodies to S. scabiei var. suis, were determined to be 0.059, 0.213 and 0.374 for weaners, fatteners and sows, respectively. The specificity of the ELISA was high (> or = 98%) for all age groups. Sensitivity was highest in the piglets (80%), followed by fatteners (78%) and sows (50%). These results indicate that an ELISA may be a simple and valuable alternative to monitor S. seabiei var. suis infections in naturally infected weaners and fatteners.

Camel trypanosomiasis and its vectors in Somalia

Blood samples from 3000 Somali camels (Camelus dromedarius) were examined for trypanosome infection. Of these, 160 (5.33%) were infected with Trypanosoma evansi, one (0.03%) with T. congolense and one (0.03%) with T. brucei. Camel trypanosomiasis occurred in most areas of tabanid infestation throughout the country. The tabanids Philoliche zonata and P. magretti are incriminated as the major vectors of the disease.

The efficacy of simplified eradication strategies against sarcoptic mange mite infections in swine herds monitored by an ELISA.

Eradication programmes directed against Sarcoptes scabiei var. suis, performed without any disinfection of the environment, were compared to an eradication programme including a simultaneous environmental disinfection. The performance of such programmes would be facilitated considerably if environmental disinfection could be avoided. The trial was conducted in four conventional piglet-producing herds designated A-D. All herds suffered from a subclinical but persistent infection with the sarcoptic mite. Herd A was treated with two injections of ivermectin and simultaneously disinfection of the environment was done. In the other herds, the animals were treated twice (B and C) or three times (D) with acaricides (ivermectin or phoxim) at intervals of 7-12 days without any simultaneous disinfection of the buildings or environment. The results were monitored by attempts to demonstrate the mite by skin scrapings, and by monitoring the levels of serum antibodies to Sarcoptes scabiei by an ELISA. Samples were taken from all adults and from 20% of the piglets aged 10-12 weeks, before initiating the control programmes, every third month during the first year and a final sampling 18 months after the treatments. After treatment, the levels of antibodies continuously decreased. Presumably dead S. scabiei were demonstrated in one sow from two of the herds 3 months after initiating acaricidal treatments. S. scabiei was not demonstrated later, nor from skin scrapings of the piglets. The results obtained demonstrate that it is possible to eradicate sarcoptic mange mites in swine herds with the use of simplified eradication programmes. The success of such programmes may efficiently be monitored by measuring the levels of serum antibodies to S. scabiei.

Long-term study of Sarcoptes scabiei infection in Norwegian red foxes (Vulpes vulpes) indicating host/parasite adaptation

The red fox (Vulpes vulpes) population, in Norway, was naïve to Sarcoptes scabiei prior to the late 1970s when this parasite was first recorded and a still ongoing epidemic started. During the course of this protracted epidemic some degree of host/parasite adaptation, with the occurrence of healthy antibody positive foxes, might be expected. In the present study the prevalence of sarcoptic mange and serologically identified S. scabiei exposure was investigated in 363 Norwegian red foxes, shot by hunters during two different study periods (1994-1995 and 2002-2005). The sarcoptic mange diagnosis was based upon the presence of clearly visible lesions in the skin of the cadaver with confirmatory demonstration of S. scabiei. The serodiagnosis was based on an indirect-ELISA. There was a significant decrease in prevalence of both mange cases and seropositive animals from the first to the second study period. Whilst the mange prevalence fell more than threefold, from 30.0% to 6.6%, the seroprevalence dropped less dramatically from 53.3% to 19.1%. The smaller decrease in seroprevalence compared to mange cases reflected a significantly higher ratio of seropositive-mange negative versus seropositive-mange positive foxes, during the second study period, 40:18, compared to the first, 14:18. These findings indicate that the red fox population is adapting to live with the parasite and that low-grade or sub-clinical infections, and even recoveries, occur amongst exposed foxes. Mange positive foxes had significantly poorer body condition than those without sarcoptic mange. No significant difference in body condition was seen between seropositive-mange negative versus seronegative-mange negative foxes. The ELISA sensitivity was found to be 95% and proved a useful tool for investigating the exposure to S. scabiei in wild foxes. This study is believed to be the first pointing to a long-term Sarcoptes/fox adaptation, combining long-term prevalence studies of clinical sarcoptic mange and serological evidence of exposure to the parasite in the general fox population.

A previously unidentified Chorioptes species infesting outer ear canals of moose (Alces alces): characterization of the mite and the pathology of infestation.

BackgroundDuring the past decade, Chorioptes mites occupying the outer ear canals have been a common finding at routine necropsies of moose (Alces alces) in Sweden, but neither the taxonomy of the mites nor lesions from the infestation have been investigated. In this study, the mites are characterized by morphological and molecular techniques, and the histopathology of the skin of the outer ear canal is described.MethodsExternal auditory meatuses from 53 necropsied moose were examined for the presence of Chorioptes, and samples from outer ear canals were taken for histopathological and microbiological examination. A proportion of the mites from each moose was identified to species. The DNA was extracted from mites from three moose, and their ITS-2 sequences were determined; these sequences were compared phylogenetically to sequences from other Chorioptes taxa.ResultsChorioptes mites were found in 43 (81%) of the 53 moose. The mites had morphological and genetic characteristics distinct from those of C. texanus and C. bovis, the two species generally accepted within the genus. Morphology also did not argue for a diagnosis as C. crewei, C. mydaus or C. panda. On histopathology, lesions were characterized by a hyperplastic perivascular to interstitial dermatitis with epidermal hyperkeratosis and crust formation. Dermal inflammatory infiltrates were composed of mixed T- and B-lymphocytes, plasma cells and macrophages, whereas eosinophils were notably uncommon. Staphylococcus aureus was grown from the infested epidermis of five of 14 examined moose.ConclusionChorioptes mite infestation was frequently detected in the outer ear canals of moose in Sweden. The mites were evidently pathogenic, being associated with inflammatory lesions of the external auditory meatus. Our studies indicate infestations with a previously undescribed Chorioptes species.

The opportunistic Sarcoptes scabiei: a new episode from giraffe in the drought-suffering Kenya.

The ubiquitous Sarcoptes mite is unexplainable emerging and re-emerging parasite, threatening biodiversity and human health. When a new outbreak occurs, it is not clear if it is a genuine emergence resulting from a new incidence or apparent emergence resulting from increased detection. In this paper we report, for the first time to our knowledge, an outbreak of sarcoptic mange in giraffes in the wild. Three decaying carcasses and five free-ranging subadult reticulated giraffes were observed to have mange-like lesions in the drought-suffering Wajir Region in North Eastern Kenya, while apparently all sympatric wild and domestic animals were mange-free. Affected giraffes were captured and successfully treated. The possible relations between this outbreak and annual seasons, animal age-classes and sex, and spatial distribution are discussed.

The spread of porcine sarcoptic mange during the fattening period revealed by development of antibodies to Sarcoptes scabiei

Using an indirect ELISA based on a whole body homogenate of Sarcoptes scabiei var vulpes, the development of serum antibodies to S. scabiei var suis during the fattening period was studied in two herds, purchasing fatteners and performing age segregated production systems. All the pigs in one of the herds were treated with ivermectin on the same day within a week after arrival, while no precautions were made to prevent sarcoptic mange in the other herd. In both herds, a transient immune response to S. scabiei was detected in some animals during the early fattening period, reflecting that these pigs had been exposed to S. scabiei before delivery to the fattening units. It also indicated that they had been treated with acaricides close to allocation. The incidence of animals seropositive to S. scabiei was initially low in both herds. The infection spread gradually as indicated by increasing optical densities of antibodies to S. scabiei, especially during the second half of the rearing period. This increase was more pronounced in the herd which had received no prophylactic treatment to sarcoptic mange. The infection with S. scabiei was found to have spread to more animals towards the end of the fattening period in that herd. It was concluded that a single injection with the acaricide on arrival at the fattening farm decreased and delayed the spread of the infection, but did not eradicate the mite infection. The results showed that conventional pigs sold as fatteners at present may be infected with S. scabiei and that precautions aimed at preventing sarcoptic mange therefore, are indicated in fattening herds. In this context, the ELISA employed could be a valuable means of discriminating between S. scabiei var suis infected piglet producing herds and uninfected herds.

Zymogram and life-history studies on trypanosomes of the subgenus Megatrypanum.

Of 13 Swedish dairy cows examined, 12 (92.3%) were found to be infected with trypanosomes by cultivation of blood samples. Of the two species of tabanid fly caught close to the cattle, 33.3% of theTabanus brornius and 8.6% of theHaematopota pluvialis were also found to be infected with trypanosomes on dissection. Isoenzyme patterns of trypanosome isolates from oneH. Pluvialis and from six cattle were identical, incriminating this fly species as a vector of the trypanosome. Comparison of these isolates with otherMegatrypanum isolates indicated that the Swedish parasites were a form ofTrypanosoma theileri and thatT. theileri and the badger parasiteT. pestanai are closely related. An isolate of aMegatrypanum from a buffalo (Syncerus caffer) in Kenya was entirely different fromT. theileri.

Important ectoparasites of Alpaca ( Vicugna pacos )

Summary Background Alpacas (Vicugna pacos), earlier named Lama pacos, belong to the family Camelidae of which there are 7 living species. Four are native to South America and of those four two are domestic species, the alpaca (Vicugna pacos) and the llama (Lama glama) and two are wild, the vicuna (Vicugna vicugna )a nd the guanaco (Lama guanicoe). These species are often referred to as the New World camels (NWCs) or the South American Camels (SACs) [1]. To the three Old World camels (OWCs) belong the bactrians or the two-humped camel (Camelus bactrianus). Lately it has been established that there are two different species of bactrians, one domesticated and one wild endangered species [2]. The latter lives on the border between Mongolia and China. The other domesticated OWC species is the more well known, the one-humped or the dromedary camel (Camelus dromedarius). The Camelidae evolved and developed parallel to the Ruminantiae over 35 million years ago in North America [1] and have developed special anatomical and physiological features which are of great significance to their biology, well adapted to the extreme climatic environments of the rough countries of deserts and semi-deserts of Asia, the Middle East and Northern Africa (OWC) and the high altitude country of the Andes in South America (SAC/NWC), respectively. The Camelidae (long neck and small head) are members of the order of Artiodactyla (even number of digits), suborder Tylopoda (modified ruminants with pad or callus on each foot). All camelids have 37 pairs of chromosomes and the karyotypes are quite similar. The SACs can interbreed and produce fertile offspring. Important livestock

Chorioptes mites: re‐evaluation of species integrity

Chorioptes mites (Acari: Psoroptidae) are non‐burrowing agents of mange which parasitize a wide range of domesticated and wild ungulates. Considerable historical confusion has surrounded the description and naming of the various species of Chorioptes. Here, the opisthosomal setae of male adult Chorioptes mites from a range of host species and geographic locations were subjected to detailed analysis. Discriminant analysis suggests the existence of three clear morphotypes. The first, Chorioptes bovis, is characterized by a very long seta 1 (ae) and short spatulate setae 2 (l4 and d5), whereas, in the second, Chorioptes texanus, setae 2 (l4 and d5) are longer and narrower than in C. bovis, but most of the other setae are shorter; this is particularly true for seta 1 (ae). A third morphotype is characterized by a seta 1 (ae) that is shorter than in C. bovis but longer than in C. texanus, long setae 2 (l4 and d5) and a long seta 6 (l5). The data are compared with previously published measurements. Although this analysis supports the validity of C. bovis and C. texanus as morphologically distinct, it also supports the existence of a proposed third species of Chorioptes, as described by Hestvik et al. in 2007, and suggests that the mites described by Sweatman in his classic 1958 description of C. texanus, which were obtained from the ears of semi‐domesticated reindeer, are likely to have been specimens of this as yet unnamed species. The results show that there is a high degree of phenotypic plasticity in setal lengths. It is concluded that a statistical difference in the absolute measurement of any one seta is not a reliable species indicator; the relative sizes of groups of setae would appear to be more taxonomically informative and should be used when identifying Chorioptes morphologically.