Plague in a complex of white-tailed prairie dogs and associated small mammals in Wyoming

Fleas were collected from white-tailed prairie dogs (Cynomys leucurus) and other small mammals trapped on six grids during a field study near Meeteetse (Wyoming, USA) in 1989 and 1990 to investigate the dynamics of plague in this rodent population. Fleas were identified and tested for Yersinia pestis by mouse inoculation. Yersinia pestis-positive fleas were found on prairie dogs and in their burrows. Flea species on prairie dogs changed from spring to late summer. White-tailed prairie dog numbers were significantly lower in the presence of Y. pestis-positive fleas; however, affected populations generally recovered 1 to 2 yr following absence of detectable plague. Grids where recovery occurred had a high proportion of juvenile male prairie dogs. Eighteen flea species were identified on small mammals, six of which were infected with Y. pestis. Some flea species were associated with a particular small mammal species, while others were found on a broad range of host species. Flea species most important in the potential interchange of Y. pestis between associated small mammals and white-tailed prairie dogs were Oropsylla tuberculata cynomuris, Oropsylla idahoensis, and Oropsylla labis. Plague cycled through the white-tailed prairie dog complex in an unpredictable manner. Each summer the complex was a mixture of colonies variously impacted by plague: some were declining, some were unaffected by plague, and others were recovering from plague population declines. These data provide insight into the dynamics of plague in white-tailed prairie dog complexes, but predicting movement of plague is not yet possible and the role of associated mammals in maintenance of plague is not understood.

Role of small mammals in the ecology of Borrelia burgdorferi in a peri-urban park in north coastal California

The role of small mammals other than woodrats in the enzootiology of the Lyme disease spirochete, Borrelia burgorferi, was assessed in the peri-urban park. Mammals were collected monthly from September through to April. Following tick removal, the animals were tested for B. burgdorferi by culture of ear-punch biopsies. Larvae and nymphs that were intermediate in morphology between Ixodes spinipalpis and Ixodes neotomae occurred on several species of rodents (Peromyscus truei, Peromyscus californicus, Microtus californicus, Rattus rattus and Reithrodontomys megalotis) and the brush rabbit (Sylvilagus bachmani). Morphometric analyses of these I. spinipalpis-like ticks and the offspring from two I. neotomae females from the site suggest that I. neotomae may bo conspecific with I. spinipalpis. Borrelia burgdorferi was isolated from eight out of 109 (7.3%), three out of 16 (18.8%), two out of 38 (5.3%) and two out of six (33.3%) P. truei, P. maniculatus, M. californicus and R. rattus, respectively. One bush rabbit yielded the first isolate of B. burgdorferi from a lagomorph in western North America. This isolate and three others derived from unfed I. spinipalpis-like nymphs failed to produce infection when inoculated intradermally into 11-12 P. maniculatus each. Likewise, no spirochetes were detected in 420 Ixodes pacificus nymphs derived from larvae fed on animals inoculated with these isolates. An additional isolate, derived from an I. spinipalpis-like nymph, was recovered by ear-punch biopsies from five our of 12 (42%) needle-inoculated P. maniculatus. However, spirochetes were not detected in 20 I. pacificus nymphs fed as larvae on each of five mice (two infected and three uninfected) inoculated with this isolate. We conclude that brush rabbits and several species of rodents besides woodrats may contribute to the maintenance of B. burgdorferi because they harbour the spirochete and are fed upon by competent enzootic vectors.

Toxoplasmosis in wild mammals from the Czech Republic

The prevalence of Toxoplasma gondii was determined in wild mammals in the Czech Republic from 1981 to 1990. The biological prevalence of T. gondii was < 1% in insectivores (n = 578), 12% in carnivores (n = 112), 1% in rodents except muskrats (Ondatra zibethicus) (n = 5,163), 24% in muskrats (n = 437), 5% in lagomorphs (n = 293), 0% in ruminants (n = 456), and 2% in wild boars (Sus scrofa) (n = 136). The seroprevalence (Sabin-Feldman dye test, titre > or = 1:4) of T. gondii was 15% in ruminants (n = 421), and 15% in wild boars (n = 124). Antibodies to T. gondii also were found in four of 10 carnivores. Toxoplasmosis is a common infection in wild mammals from the Czech Republic, but its prevalence varies considerable according to taxonomic groups and different localities where wild mammals live.

Efficacy of ivermectin against nematodes infecting field populations of snowshoe hares (Lepus americanus) in Yukon, Canada

From July 1990 to February 1991, nematode numbers in free-ranging snowshoe hares (Lepus americanus) at Kluane Lake, southwestern Yukon, Canada, were manipulated by subcutaneous injection (0.4 mg/kg) of ivermectin. Three field experiments were conducted to determine the degree of helminth loss associated with a single administration of ivermectin; the length of time that ivermectin was effective in reducing worm numbers; and the effect of repeated ivermectin administration in reducing worm numbers. Numbers of the nematodes, Protostrongylus boughtoni and Nematodirus triangularis were reduced by approximately 80% 2 wk after treatment with a single dose of ivermectin, and were still significantly lower than controls at 4 wk. However, beyond 2 wk, ivermectin did not affect the rate of acquisition of new worms of either species. All treated groups contained one or more hares in which numbers of P. boughtoni and N. triangularis were not reduced. In addition, ivermectin had no effect on numbers of Trichuris leporis or Passalurus sp. Overall, ivermectin was not as effective against the nematodes of free-ranging hares as has been reported for nematodes of domestic and laboratory animals.

Parasites of domestic and wild animals in South Africa. XXXIII. Ixodid ticks on scrub hares in the north-eastern regions of northern and eastern Transvaal and of KwaZulu-Natal

Ixodid ticks were collected from scrub hares (Lepus saxatilis) at three localities. Nine tick species were recovered from 24 hares examined at Pafuri, Kruger National Park, Northern Transvaal. The most abundant and prevalent species were Hyalomma truncatum, Rhipicephalus kochi and a Rhipicephalus species (near R. pravus). Twelve tick species were collected from 120 scrub hares examined around Skukuza, Kruger National Park, Eastern Transvaal. The immature stages of Hyalomma truncatum were most abundant and those of Amblyomma hebraeum most prevalent on the hares. No haematozoa were found on blood smears made from these hares. Thirty-four scrub hares on mixed cattle and game farms near Hluhluwe, north-eastern KwaZulu-Natal harboured 12 tick species. The most abundant and prevalent of these were the immature stages of Rhipicephalus muehlensi. Piroplasms, tentatively identified as Babesia leporis, were present on blood smears of eight of these hares. The host status of scrub hares for 18 ixodid tick species or subspecies found in South Africa is tabulated.

Fleas, lice and mites on scrub hares (Lepus saxatilis) in northern and eastern Transvaal and in KwaZulu-Natal, South Africa

Fleas, lice and mites were collected from 24 and 120 scrub hares at Pafuri and Skukuza, Northern and Eastern Transvaal, respectively, in the Kruger National Park, and from 34 scrub hares in the Hluhluwe region, north-eastern KwaZulu-Natal. Ctenocephalides felis damarensis, the only flea recovered, reached peak burdens on the hares at each locality during late winter or spring. Juvenile hares harboured significantly fewer fleas than did adult animals. The lice Haemodipsus lyriocephalus and Haemodipsus setoni were collected from hares at each locality, with H. setoni generally being the most abundant. Listrophorus leporicolus was found on hares at Skukuza and Hluhluwe, and mites of the genus Cheyletiella were collected from hares at Skukuza.

Serologic survey for Toxoplasma gondii infection in the brown hare (Lepus europaeus P.) in Sweden

Serum samples from 176 brown hares (Lepus europaeus P.) shot in three areas of south and central Sweden during 1984 and 1985 were analyzed for antibodies to the protozoan parasite Toxoplasma gondii using several serological assays. No toxoplasma antibodies were detected in any of the sera, either by direct agglutination test or by ELISA, and selected sera were also negative in the IFAT and the Sabin Feldman dye test. Based on the high incidence of acute fatal toxoplasmosis in hares in Scandinavia, we propose that the brown hare is exceptionally susceptible to primary T. gondii infection.

Toxoplasma gondii virulence: changing pattern under different maintenance conditions

Toxoplasma gondii parasites were isolated in vitro and in vivo from a hare that had died of disseminated toxoplasmosis. Intraperitoneal inoculation of either homogenate of hare organs or parasites isolated on culture produced chronic infection in mice. However, a progressive increase of virulence following subsequent mouse-to-mouse transfections was observed. These findings suggest that host-parasite interaction plays a major role in determining the degree of pathogenicity, and that in vitro and in vivo isolation, if not followed by subsequent passages, may fail to reveal major differences in virulence between isolates.

Parasites of domestic and wild animals in South Africa. XXXII. Ixodid ticks on scrub hares in the Transvaal

A total of 264 scrub hares (Lepus saxatilis) were examined for ixodid ticks at various localities in the Kruger National Park, eastern Transvaal Lowveld. Thirteen tick species were recovered from these hares. The seasonal abundances of the immature stages of Amblyomma hebraeum, Amblyomma marmoreum, Hyalomma truncatum, Rhipicephalus appendiculatus, Rhipicephalus evertsi evertsi, Rhipicephalus simus and Rhipicephalus zambeziensis and all stages of a Rhipicephalus sp. (near R. pravus) were determined. Three scrub hares, examined in the north-western Transvaal Bushveld, were infested with five ixodid tick species. Ten hares examined in the eastern Transvaal Highveld harboured three species. A total of 15 ixodid tick species were recovered from the scrub hares examined in the three regions of the Transvaal. No haematozoa were found in blood smears made from the hares examined in the southern region of the Kruger National Park.

Fleas and lice on scrub hares (Lepus saxatilis) in South Africa

A total of 380 scrub hares (Lepus saxatilis) from 5 localities, ranging from the north-eastern Transvaal to the eastern and the south-western Cape Province of South Africa, were examined for fleas and lice. Ctenocephalides felis damarensis was almost exclusively responsible for the flea infestations on hares at 4 of the 5 sites. At 4 localities the prevalence and abundance of this flea reached peaks between August and October and declined thereafter to their lowest levels between February and April. Its prevalence and abundance in the north-eastern Transvaal were not correlated with the breeding cycle of the hares in this region. The 2 louse species recovered, sometimes sympatrically, were Haemodipsus lyriocephalus and Haemodipsus setoni. Listrophorus leporicolus was the only mite species recovered.

Blood chemistry and endoparasites of the mountain hare (Lepus timidus L.) in high and low density populations

In order to study the effect of high population density on the condition, blood characteristics and helminth parasitism of mountain hares (Lepus timidus), 12 specimens were shot in December 1982 and 12 more in February 1983 on the west coast of central Finland (group 1, dense population). In addition 14 hares were shot in December 1982 about 100 km from group 1 (group 2, dense population). Group 3 consists of 15 hares from stable, rather low density populations shot in southern Finland during three previous winters. The hares in group 1 were the lightest, had the least fat and were the most seriously infected with Protostrongylus pulmonalis and Trichostrongylus retortaeformis, while those in group 2 were the heaviest and had the highest Ca, Mg, alkaline phosphatase and creatinine values. The group 3 hares had the most fat. The group 1 animals shot in February 1983 had higher Ca, Mg, triglyceride and cholesterol values than those shot in December 1982. It seems that high population density combined with a lack of suitable food leads to poor condition and high endoparasite abundances. The differences in Ca and Mg are probably due to diet. The higher creatinine values in group 2 and in the hares with little or no T. retortaeformis infection may be due to the greater muscle mass.

[Focal changes in the lungs of wild hares caused by the parasite Protostrongylus commutatus (Diesing, 1851)]

The pathomorphological changes in the lungs of hare (Lepus europaeus Pallas, 1778) provoked by the parasite P. commutatus (Diesing, 1851) are macroscopically manifested as layer and nodular changes. With regard to the fact that the layer changes are suggesting the hatching nodules of protostronglyoses of small domestic ruminants, we have decided to rate them separately because of the differentiation. The layer changes on the surface of hare's lungs become evident as areas of emphysema, inflammation and induration. The emphysematous changes are macroscopically evident in the form of lobular formation (Fig. 1). Histologically, it was found out that the emphysematous effect was limited by an area of compressed lungs structures without perspicuous signs of the development of atelectatic changes (Fig. 2). The emphysematous changes are causing prominent exudative inflammatory processes in the bronchi and bronchioli provoked by unfertilized and disintegrating eggs of parasites. Inflammatory layers are macroscopically evident as solid brown-reddish areas (Fig. 3). Their macroscopic manifestation is transient. It is qualified by the stages of the inflammation itself. It is possible to put down the stage of manifestative development of the changes in the inflammatory areas only by continual examinations of hare's lungs all year round. Unfertilized eggs and grounded, disintegrating larvae of protostrongylus are provoking the inflammatory reactions which may lead in the layer changes to the obliteration of bronchioli (Fig. 6), which is macroscopically evident as induration (Fig. 7). The bronchioli are obliterated so that the phagocytic ability of monocytes is transformed to a reparative ability.(ABSTRACT TRUNCATED AT 250 WORDS)

Parasites of domestic and wild animals in South Africa. XXIX. Ixodid ticks on hares in the Cape Province and on hares and red rock rabbits in the Orange Free State

One hundred and seventeen scrub hares, Lepus saxatilis, were examined for ixodid ticks in various regions of the Cape Province. They were infested with 18 tick species and the seasonal abundances of the immature stages of Amblyomma hebraeum, Amblyomma marmoreum, Hyalomma marginatum rufipes, Rhipicephalus appendiculatus and Rhipicephalus glabroscutatum and all stages of Rhipicephalus oculatus and the adults of a Rhipicephalus sp. (near R. oculatus) were determined. Seventy-two scrub hares on 3 farms in the Orange Free State harboured 10 ixodid tick species and the seasonal abundances of the immature stages of H. marginatum rufipes and Hyalomma truncatum and all stages of Rhipicephalus punctatus were determined. Thirty Cape hares, Lepus capensis, examined in the northern Cape Province harboured 5 tick species and the seasonal abundances of the immature stages of H. marginatum rufipes and H. truncatum were determined. Thirty-four Cape hares examined in the south-western Orange Free State carried 6 tick species and the seasonal abundance of immature H. marginatum rufipes was determined on these animals. Twenty-eight Smith's red rock rabbits examined on 2 farms in the south-western Orange Free State were infested with 7 tick species.

[The development of methods for the absolute count of the population of ixodid pasture ticks in open landscapes. 3. The count of hungry Dermacentor nuttalli Olen., 1919 larvae and nymphs in the steppe regions of the Transbaikal area]

Methods for absolute registration of the number of hungry larvae and nymphs directly in the places of their natural habitation have been elaborated. Specific features of the activation of these phases in Transbaikal conditions have been studied. Peaks of their seasonal activity can be observed in July. It has been shown that the results of single (during seasonal peak in their number) capture of larvae and nymphs from all animal holes over a 100 m2 area can be used for characterization of density. Single capture accounts for 9-15% larvae and 12-16% nymphs of the total number of activized individuals. To assess reliably mean larval and nymph density, with the inadequacy of the results of absolute registration being 30%, not less than 100-130 areas should be examined.

Protostrongylus pulmonalis from hares (Lepus europaeus) in Italy

Protostrongylus (Pulmostrongylus) pulmonalis from Lepus europaeus in Italy (Alto Adige) was studied. Most of the parasite population showed the typical morphology described for this species. Variations observed in the morphological features of gubernaculum, antero-lateral ray and telamon are considered to lie within the range of variability of the species. This is the first record of Protostrongylus (Pul.) pulmonalis in hares in Italy.

Interaction of the tick (Haemaphysalis leporispalustris) with a cyclic snowshoe hare (Lepus americanus) population

Prevalence and intensity of the tick, Haemaphysalis leporispalustris, were monitored during 1963 to 1976 in a cyclic snowshoe hare (Lepus americanus) population near Rochester, Alberta, Canada. Prevalence was near zero from December through March, and near 100% among adult hares from May through September. Prevalence among juvenile hares approached 100% by age 2 mo. Intensity peaked for both adults and juveniles during May-June and again in August. Mean intensities were significantly higher among adult males than adult females in 5 of 13 yr, and almost significant in two others. Tick intensities were lowest during 3 yr, 1969 to 1971, when hare densities were highest. Tick intensities in spring were correlated with intensities the previous fall. Survival of marked adult and juvenile hares was unrelated to intensities of infestation. Mean numbers of corpora lutea and embryos tended to be lower among adult females with heavy tick infestations, and intra-uterine losses rose steadily from about 3 to 13% as tick intensities increased from none to heavy. Comparison of average tick intensities on adults 1-, 2-, and greater than or equal to 3-yr-old yielded no evidence of increased immunity with age.

The Syphaciinae (Oxyuridae, Nematoda) parasitic in rodents and lagomorpha. Numerical taxonomy. Cladistic analysis of evolution

Two different methods are successively used for the systematic study of the Syphaciinae, a parasitic group of pin-worms specific for the Rodents and Lagomorpha. The statistical method permits to build a "phenetic classification"; the cladistic method permits to build a "phylogenetic classification". The classification finally proposed is principally found on the results of the morphological study of the parasites, but has also in view the integration of all available data concerning the biology, the biogeography and the phylogeny of the hosts.

The scrub hare, a reliable indicator of the presence of Hyalomma ticks in the Cape Province

The host preferences of immature and adult Hyalomma marginatum rufipes, Hyalomma marginatum turanicum and Hyalomma truncatum were studied at various localities in the Cape Province. The immature stages of all 3 ticks preferred scrub hares (Lepus saxatilis) as hosts and were recovered from these animals even when few adult ticks were present on large herbivores in the locality. Ground-frequenting birds were also infested, but only with immature H. marginatum rufipes and H. marginatum turanicum. Some small rodents were also infested but only with the immature stages of H. truncatum. The adult ticks preferred Cape mountain zebra (Equus zebra zebra), eland (Taurotragus oryx) and cattle. The immature stages of H. marginatum rufipes were most abundant on scrub hares from February to August. Too few adult ticks of this species were recovered to determine their seasonal abundance. The immature stages of H. marginatum turanicum were most abundant on scrub hares during the winter months and the adults were most abundant on scrub hares during the winter months and the adults were most abundant on Cape mountain zebra and eland during summer. Immature H. truncatum were most abundant on scrub hares during February and May, while peak adult burdens were found on zebra and eland during February, August, November and December.

A comparison of the tick burdens of wild animals in a nature reserve and on an adjacent farm where tick control is practised

Acaricidal treatment of cattle, sheep and goats on a farm in Valley Bushveld in the Grahamstown district resulted in a reduction in the numbers of certain tick species on kudu (Tragelaphus strepsiceros), scrub hares (Lepus saxatilis) and crowned guinea fowl (Numida meleagris) on the same farm. The tick species most severely affected was Amblyomma hebraeum, while Haemaphysalis silacea, Hyalomma marginatum rufipes and Rhipicephalus appendiculatus were affected to a lesser extent. Rhipicephalus glabroscutatum and Rhipicephalus oculatus appeared to be unaffected.

Parasites of domestic and wild animals in South Africa. XXI. Arthropod parasites of vaal ribbok, bontebok and scrub hares in the western Cape Province

Vaal ribbok (Pelea capreolus), bontebok (Damaliscus dorcas dorcas) and scrub hares (Lepus saxatilis) were slaughtered in the Bontebok National Park at regular intervals and examined for arthropod parasites. Twelve species of ixodid ticks were recovered; the antelope each harboured 9 species and the hares 11. Rhipicephalus nitens was the most prevalent and most abundant tick. The vaal ribbok also harboured large numbers of Ixodes pilosus and the bontebok fairly large numbers of Rhipicephalus glabroscutatum. The vaal ribbok were infested with 2 lice species and the larvae of 3 oestrid fly species. The bontebok harboured 2 lice species and the larvae of 2 oestrid flies, and the scrub hares were infested with a louse species and a flea species. The host preference and seasonal abundance of some of the parasites were determined.

Parasitism in a declining population of snowshoe hares

Prevalence and intensity of six endoparasites were determined in 346 snowshoe hares (Lepus americanus) obtained at Rochester, Alberta, during December-April 1981-1982, the second winter of a cyclic population decline. The data were analyzed for (1) differences among host sex and age classes, and among months and sample sources, and (2) evidence that parasitism was of demographic significance to the hare population. Prevalence and intensity of Obeliscoides cuniculi were consistently highest among adult hares, but rose most sharply from February to March among juveniles. In contrast, prevalence and intensity of Nematodirus triangularis were highest among juveniles; prevalence reached 90-100% by January, whereas intensity continued to rise through April. Prevalence and intensity of both Trichuris leporis and Protostrongylus boughtoni were highest also among juvenile hares; neither parameter exhibited a definite trend over time. Prevalences of Taenia pisiformis (cysticerci) and Eimeria spp. were unrelated to sex, age or month; but Taenia intensity was highest among juveniles, and Eimeria intensity tended to decrease from December to April. Intensities of Nematodirus, Protostrongylus and Eimeria were higher in male hares than in females. Prevalence and intensity were correlated directly in Obeliscoides, Nematodirus, Trichuris and Eimeria. Hares that died during trapping and handling, or from natural predation, had greater intensities of Obeliscoides than did animals killed on purpose. There was no indication, however, that risk of death was increased by the other parasitic infections. Age-related immune responses to parasitism (except Obeliscoides) were evidenced by reduced or stabilized prevalence and/or intensity among older hares. A multiple-regression model predicted depressed body weight with increasing intensities of Nematodirus, Trichuris or Protostrongylus. Other body-condition and reproductive indices were unassociated with parasite intensities. Within the hare population, Obeliscoides, Trichuris, Protostrongylus and Taenia had overdispersed distributions (typical of many endoparasites) that did not differ from a negative binomial. The frequency with which each possible combination of helminth species occurred within individual hares was consistent with the assumption that such infections occurred independently. There was no compelling reason to believe parasitism was a significant factor in the overwinter decline of this population of snowshoe hares.

The occurrence and abundance of helminth parasites of the mountain hare Lepus timidus (L.) and the wild rabbit Oryctolagus cuniculus (L.) in Aberdeenshire, Scotland

Mountain hares were collected each month between April 1984 and March 1985 and their intestines examined for helminths. 26 rabbits were also collected between July and December 1984 and examined for gastro-intestinal helminths. Three nematode and two cestode species were found in the hares while only two nematode and one cestode species were found in the rabbits. Trichostrongylus retortaeformis was recorded from 88% of the 193 hares and 92% of the rabbits while comparable figures for Passalurus ambiguus were 0.5% and 54% and for Mosgovoyia pectinata 14% and 81%. Seasonal fluctuations were observed in the T. retortaeformis populations in the hare; numbers tended to be low during the winter months and high throughout the summer. Paranoplocephala wimerosa was reported for the first time from the British Isles and Trichostrongylus axei was recorded for the first time in the mountain hare.

[Toxoplasmas of wild warm-blooded animals in Turkmenia]

Antibodies to Toxoplasma in the reaction of indirect hemagglutination were found in 8 species of mammals and 2 species of birds. Carriage of antibodies to Toxoplasma in house mouse, common fox, bald coot , and rock-dove was first recorded from Turkmenia . Analysis of the infection with Toxoplasma according to species, habitat of antibodies carriers, their ecology, age, sex and season of investigation is given.

[A Danish pathography from the 17th century (Johan Valentin Wille) (author's transl)]

A monograph written by the physician Johan Valentin Wille in 1675 is discussed and commented. The monograph was published in Th. Bartholin Acta medica, the first medical journal in Denmark, and was in 1934 translated from Latin into Danish by the physician Eiler Høeg. It givees a detailed description of organ changes and internal parasites found in cattle and hare autopsied on Sealand 1674-75. Vermiform bodies found in the liver of cattle are undoubtedly identical with Fasciola hepatica. The tumorous or cystic formations in the bovine lung and liver correspond certainly with the larval stages of Echinococcus granulosus and the small cysts arranged as "bunches of grapes" on the liver surface and mesentery of hares cannot be anything else than Cysticercus pisiformis. It is possibly the first description of the mentioned parasites in animals in Denmark. The observations are published almost two centuries before the life-cycles of these parasites were finally clarified and about one century before the Danish Veterinary School was established at Christianshavn (in Copenhagen) and the founder Abildgaard started to publish his interesting observations on intestinal parasites.--The monograph is typical for that particular time, reflecting the decline of the medieval humoralism and the growth of the Renaissance science.

[Presence of adiaspores of Emmonsia crescens Emmons and Jellison, 1960, a moniliaceous, aleurioid fungus, in the lungs of small wild mammals in northern Morocco]

The authors examine the lungs of 133 small mammals caught in the North of Morocco and belonging to 7 species: 12,8% of the animals (14/95 A. sylvaticus, 1/18 M. spretus and 2/11 C. russula) possess one adiaspore of E. crescens or more hundred. The relatively damp climate of this region can explain this strong percentage of infestation. That is the first time that the adiaspiromycosis is noticed in small mammals in North Africa and the second time on the African continent.

Case reports of bot fly myiasis in pikas (Ochotona princeps)

Six cases of bot fly (Cuterebra spp.) myiasis in pikas (Ochotona princeps) are reported from Oregon and Montana. These are the first known cases of Cuterebra parasitism of pikas.

[Nematodirinae (Nematoda) from Ruminants and from lagomorpha. (author's transl)]

Study of eight species of Nematodirinae with special emphasis on their synlophe: Nematodirus filicollis (Rudolphi, 1802), N. spathiger (Railliet, 1896). N. helvetianus May, 1920, N. battus Crofton & Thomas, 1951, N. tortuosus Tucker, 1942, Nematodirella dromedarii (May, 1920), Nematodiroides zembrae (Bernard, 1965) and Rauschia triangularis, type species of the new genus Rauschia. Furthermore, bibliographical data permit to know the structure of the synlophe in four other species. In each of these species the synlophe retains the primitive bilateral symmetry observed in the Molineidae; in species parasitic in Ruminants and Rodents, the synlophe shows non pronounced size gradient, nor a pronounced peculiar orientation of the tip of the crests. These last specialized characters are observed, on the contrary, in species parasitic in Lagomorpha. These latter show, starting from synlophes of the "Anoplostrongylinae"-type, various evolutionary essays; the most remarkable is an hypertrophy of the dorsal crests which leads at the end of the evolution, to a dextral coiling, the back of the animal being inside the spire: such a position appears unique in the superfamily. Rauschia gen. nov. (type species: R. triangularis) is created for species previously pertaining to Nematodirus parasite of Lagomorpha, and in which the synlophe, very complex, differs from the synlophe of the parasite of Ruminants. A dichotomic key of the six genera of Nematodirinae is proposed.

The limiting effect of host availability for the immature stages on population growth in economically important ixodid ticks

Of 12 southern African species of ixodid ticks in which the adults are commonly parasitc on cattle, only 4 exhibited massive increases in abundance in the absence of dipping. It is suggested that host availability for the immature stages is the major factor limiting population growth in a given environment. The species showing large increases in abundance are those in which the immature stages are predominantly parasitic on cattle, whereas the species showing small to moderate increases in abundance are those in which the immature stages are parasitic on specific nonungulate hosts.

[Paradoxopsyllus scorodumovi (Aphaniptera) flea, an effective vector of plague in a Gorno-Altai natural focus]

A study was conducted on the fleas of P. scorodumovi and five local strains of the plague microbe, one of which is typical of the strains of the Altai subspecies and four are non-typical of this nidus. The fleas of this species are capable to transmit not only the plague agent of the strains typical of this nidus but also non-typical ones which differ in some biological properties and are avirulent for most carriers but Pallas's pika. Biological peculiarities of fleas of P. scorodumovi in addition to their high efficiency as vectors of the plague microbe enable us to associate the more active autumn epizooty with fleas of this species.

[Epizootiological importance of Frontopsylla hetera (Siphonaptera) fleas in the Gorno-Altai natural plague focus]

Experiments conducted during all seasons have established that F. hetera, one of the mass species of fleas in Mountain Altai, can be infected both by the strain of selective virulence typical to this nidus and by the non-typical non-virulent mountain-altai strain of plague agent. The non-virulent strain does not form in fleas the block of proventriculus and within 1.5-2 months they become free from the microbe. At the infection with the typical strain of the altai subspecies rare transmissions of the agent to Pallas' pika can take place as well as its long preservation in fleas.

The morphology and histochemistry of eggshell formation in Cephaluris coloradensis, a parasite of pikas

Histochemical and histological studies of Cephaluris coloradensis (Nematoda: Oxyuridae) a parasite of pikas (Ochotonidae), show that in this species the eggs are each enclosed by three shells. The inner shell is chitin with an operculum at one end; the operculum is chemically distinct. The other two shells are lipoprotein. The inner lipoprotein shell is new, not previously reported in nematode species. It forms after the outer lipoprotein shell but beneath it, and is believed to be a product of the egg. The new layer encircles part of the embryo. A thin mucoprotein cementing substance binds the inner lipoprotein shell to the chitinous shell. A thin outermost mucoprotein layer formed from secretions of the uterus covers the eggshell.

Haemaphysalis (allophysalis) danieli, sp. n. (ixodoidea: ixodidae), female and tentatively associated immature stages from high mountains of northern Pakistan and Afghanistan

Haemaphysalis (Allophysalis) danieli sp. n. is described from a female taken from alpine vegetation in Swat, Pakistan. Fifty-one nymphal and larval ticks tentatively associated with this taxon are from hamsters, field mice, voles, and marmots (Rodentia), Cricetulus migratorius, Apodemus flavicollis, alticola roylei, and Marmota caudata, and from pikas (Lagomorpha), Ochotona roylei, in Gilgit and Hazara districts of Pakistan and in Badakhashan Province of Afghanistan. Collecting localities are in the western Himalayan mountain complex between 2,310 and 4,000 m altitude and between 35degrees08' and 36degrees23' N and 71degrees51' and 74degrees02' E. This species is most closely related to the mountain-inhabiting H. (A9Y pospelovashtromae Hoogstraal of southern USSR and Mongolia and H. (A.) garhwalensis Dhanda and Bhat of northern India and Nepal.

[Cultivation of the warble-fly Oestromyia leporina pall. (Diptera, Hypodermatidae) and its biological prerequisites (author's transl)]

The warble-fly Oestromyia leporina was cultivated for four generations in the laboratory. In the present paper the technic of laboratory mating and the modus of experimental infection of the host are described. The fertility of females is tested by experiments and by dissections. It is shown how the diapause of the puparia can be shortened and how it can be omitted. The successful infection of several species of small mammals demonstrates that O. leporina can be colonized not only on the natural host but also on some common laboratory animals like mice and rats.

Sylvatic echinococcosis in Argentina. I. On the morphology and biology of strobilar Echinococcus granulosus (Batsch, 1786) from domestic and sylvatic animal hosts

Dogs were fed larvae of Echinococcus granulosus (Batsch, 1786) recovered from sheep in Argentina. The morphological characteristics of strobilae recovered from dogs at 28, 60 and 76 days postexposure were compared with those of Echinococcus spp. recovered from naturally infected foxes, Dusicyon clupaeus (Molina) and D. griseus (Gray), and those of worms reared in dogs from larvae in European hares, Lepus europaeus (L.). Only slight differences were observed in characters of taxonomic importance and it was concluded that all cestodes represented a single species, E. granulosus. The results are discussed as they bear on the speciation controversy and the potential epidemiology importance of Dusicyon spp. as hosts of E. granulosus. It was suggested that E. patagonicus Szidat, 1960 previously described from D. culpaeus is conspecific with E. granulosus. E. cepanzoi Szidat, 1971 is probably also a synonym of E. granulosus and the subspecies E. g. dusicyontis Blood and Lelijveld, 1969, is rejected on the grounds that there is no evidence for host specificity and ecological or other segregation from the nominate form. Foxes appear to become infected from scavenging on dead sheep in localities where E. granulosus is endemic in domestic animals. There is still no evidence that E. granulosus is maintained in Argentina in sylvatic cycles.

Studies on the ecology of Amblyomma marmoreum Koch 1844 (Acarnia: Ixodidae)

In the Eastern Cape Province of South Africa, larvae and nymphs of Ablyomma marmoreum Koch occur in habitats in which there is tree cover and herbaceous ground cover. Immatures of A. marmoreum are parasitic on reptiles, birds, and mammals. Adults occur only on reptiles. The major host for all stages is the moutain tortoise (Geochelone pardalis), and in the home areas of tortoises the density of ticks is high. Larvae are active in late summer and autumn. The rate of feeding is temperature-dependent, and some larvae which attach on tortoises in late autumn do not complete feeding until the following spring. Nymphs which occur in the home area of a tortoise become active in response to CO2 in early spring. Adults, and nymphs which occur outside the home area of a tortoise, become active in summer in response to rising temperatures. In nymphs which feed in spring, and hence develop into adults in midsummer, the life cycle is completed in 1 year. In nymphs which fed in midsummer, the life cycle is completed in 2 years.

Studies on the ecology of Haemaphysalis silacea Robinson 1912 (Acarina: Ixodidae)

Haemaphysalis silacea Robinson is known to be established only in the Eastern Cape Province of South Africa, in localized areas of Fish River Bush in the river valleys and in the coastal bush complex. In the Kowie River valley, it was shown that the distribution of larvae is limited by microclimatic conditions. The humid leaf litter zone in the dense vegetation on the river banks and along minor tributaries is the focus of the larval population. Nymphs are most numerous in drier microhabitats on the wooded, river floodplain. Larvae are active during the humid conditions of autumn and early winter, nymphs during late winter and spring, and adults during the hot, dry summer months. The main hosts of H. silacea are artiodactyls, which are numerous in the dense Fish River Bush. The host/tick interaction occurs as a result of the daily movements and feeding habits of the hosts.

Two new species of nematodes of lagomorphs and rodents from Iran

Two new species of helminths, Fastigiuris prudhoei from Ochotona rufescens Gray, 1842, and Trichuris mofidii from Rhombomys opimus Lichtenstein, 1823, have been identified and described from mammals collected in Iran.