The biology and epidemiology of Eimeria exigua, a parasite of wild rabbits invading the host cell nucleus.

Prevalence and intensity of infection with Eimeria exigua were studied by monthly sampling of caecal faeces of 254 wild rabbits (Oryctolagus cuniculus) from 5 localities in France (Arjuzanx, Versailles, Donzere-Mondragon, Massereau, Gerstheim) and by a single sampling in autumn in a small island off the coast of Britany (Beniguet). Intensity was heavier in young than in adult rabbits but usually remained low. It decreased from north to south, was at a maximum during autumn and winter, and declined in spring. Prevalences were relatively high and their rank (4th or 5th out of 10) was constant in all localities. Prevalences decreased from north-west to south-east; they increased progressively during autumn and winter, were at a maximum during spring and declined in summer. E. exigua developed in the ileum, at the top of the villi and inside the host-cell nucleus. It is distinguished from congeneric species by a number of features: micro-localisation, multiplication in autumn and winter rather than in summer, low intensity and high prevalence. These characteristics may be the consequence of a short schizogony phase and of strong resistance of oocysts.     

Gastrointestinal Parasites in Crop Raiding and Wild Foraging Papio anubis in Nigeria

We compared parasitic infection in a crop-raiding and a wild-foraging troop of olive baboons, Papio anubis, in Gashaka Gumti National Park, Nigeria, to quantify how crop raiding may have influenced primate-parasite interactions. We recovered gastrointestinal parasites from fecal samples from all adult individuals in both troops and processed them via formal-ether sedimentation. We compared parasitic species richness, prevalence, output, and load across troops. We recovered 9 parasite taxa. The wild-foraging troop had a significantly higher mean output than the crop-raiding troop for Physaloptera sp., Trichuris sp., and also a significantly higher total helminth load. The crop-raiding troop had a significantly higher mean output for the protozoan Balantidium coli and also showed a higher parasitic species richness, with 9 species recovered compared to the 7 recorded for the wild-foraging individuals. The changes in nutritional intake, behavior, and human proximity caused by crop raiding may have important epidemiological impacts on wild primate populations, and the nature of such impacts may vary across different taxa of parasites.     

Interpopulation variation in the prevalence and intensity of parasitic mite infection in the land snail Arianta arbustorum

Abstract. The parasitic mite Riccardoella limacum sucks blood in the lung of its host, the land snail Arianta arbustorum . The infection of various host populations was examined in Switzerland. In a lowland snail population, prevalence of infection did not vary among seasons. However, intensity of mite infection in dissected individuals of A. arbustorum was high in autumn, but low in winter and spring when ≤100 mite eggs were found attached to the lung epithelium. A novel, non-invasive parasite screening method was used to estimate the number of mites on living host snails. An analysis of repeatability revealed that 92.9% of the snails were correctly classified as infected or non-infected with this non-invasive method. Prevalence of mite infection was examined in 997 adults of A. arbustorum from 11 natural populations distributed over an altitudinal gradient ranging 335–2360 m. No infected snails were found in 7 populations, while in the remaining 4 populations the prevalence of mite infection ranged 45.8–77.8%. Intensity of infection also differed among the 4 host populations. No geographic pattern in prevalence of infection was found. However, parasitic mites did not occur in snail populations situated at elevations of 1290 m or higher. A possible explanation for this finding could be that the host's hibernation period may be too long at high elevations for mites and their eggs to survive. At low elevations, other factors may affect the presence of R. limacum in the lung of A. arbustorum .     

Influence of habitat modification on the intestinal helminth community ecology of cottontail rabbit populations

The influence of five brush management treatments using the herbicides tebuthiuron and triclopyr, with or without prescribed burning, on the intestinal helminth community of cottontail rabbits (Sylvilagus floridanus) was studied in 1987 on the Cross Timbers Experimental Range in Payne County, Oklahoma (USA). Six helminth species were found (Dermatoxys veligera, Trichostrongylus calcaratus, Passalurus nonanulatus, Wellcomia longejector, Taenia pisiformis cystercercus, and Mosgovoyia pectinata americana) in 102 rabbits (88 adult and 14 juveniles) collected over two seasons (winter and summer). Prevalence of M. pectinata americana in cottontail rabbits was significantly greater in untreated control pastures than herbicide treated pastures in winter, while prevalence of T. pisiformis was significantly greater in burned than unburned pastures. Abundances of helminth species in the intestinal tract of cottontail rabbits were unaffected by brush treatments. Mosgovoyia pectinata americana abundance demonstrated a highly significant increase from winter to summer; conversely, abundance of all oxyurid pinworms combined (D. veligera, P. nonanulatus, W. longejector) was significantly higher in winter than summer. Helminth community dynamics were significantly influenced by season, but were unaffected by brush treatments. Habitat modification could have influenced cestode transmission by altering the ecology of invertebrate and vertebrate hosts.     

Epifaunistic arthropod parasites of the four-striped mouse, Rhabdomys pumilio, in the Western Cape Province, South Africa

Flea, lice, mite, and tick species associated with 510 Rhabdomys pumilio were collected at 9 localities in the Western Cape Province, South Africa. The aims of the study were first to quantify the species richness, prevalence, and relative mean intensity of infestation of epifaunistic arthropod species associated with R. pumilio, and second to determine temporal variations in the mean abundance of the parasitic arthropods. Each mouse was examined under a stereoscopic microscope and its parasites were removed, identified, and quantified. The epifaunal population was made up of more than 25,000 individuals and included 8 flea, 1 sucking louse, 11 mite, and 13 ixodid tick species. Female-biased sex ratios were noted for 9 (30%) of the ectoparasite species. Three undescribed mite and 1 undescribed tick species were recovered, and new locality records for 2 flea, the louse, and 2 mite species were documented. A phoretic host association between a nonparasitic mite species, Psylloglyphus uilenbergi kivuensis, and 3 flea species, Chiastopsylla rossi, Hypsophthalmus temporis, and Listropsylla agrippinae, was recorded. The mean abundance of the parasitic mite and insect species were higher during the cold wet season, whereas ticks were more numerous during the warm dry months. The large number of ectoparasite species on R. pumilio, a locally abundant and regionally widespread species, is of medical and veterinary importance particularly in relation to the transmission of pathogens such as Anaplasma marginale, Babesia caballi, and Babesia canis to domestic animals; Rickettsia conori; Yersinia pestis; and the viral disease Crimean-Congo hemorrhagic fever to humans.     

The annual cycle of shedding Eimeria oocysts by European bison (Bison bonasus) in the Bialowieza Primeval Forest, Poland

Between April 2008 and March 2009, we analyzed the pattern of coccidian oocysts present in the feces of the European bison (Bison bonasus L., 1758) and found 4 species (Eimeria bovis , E. canadensis, E. ellipsoidalis, E. zuernii) previously reported from this host and 3 species (Eimeria alabamensis, E. cylindrica, E. pellita) that are new host and locality records. All the species occurred in bison females, and only 4 occurred in males; E. bovis was the most prevalent in both sexes. The overall prevalence of Eimeria spp. invasion reached 34.7% in cows and 13.9% in bulls. The highest prevalence was noted in early spring, with a peak in April, and the lowest in late autumn and winter. The oocyst count per gram of feces (OPG) varied from 50 to 1,350; no symptoms of clinical coccidiosis were observed. We found a significant influence of winter aggregations of bison on shedding of coccidian oocysts. The prevalence and OPG values were higher in bison congregating in large numbers around winter-feeding sites in comparison to other sites. We suggest that the coming together of cows during the growing season impacts the gender-related differences in prevalence and the number of coccidian species involved. This observation probably results from an increased production of oocysts by sub-clinically infected individuals in high-density bison populations.     

Habitat and management influence on a seasonal diet composition of wild boar

The purpose of this study was to compare the diet composition of two wild boar populations living in the Czech Republic, one living in a floodplain, broadleaved, forest (A) and the other in a highland mostly coniferous forest (B). Food consumed by A showed to be mostly of natural origin, while that of B was predominantly supplemented. The diet consisting of natural resources was significantly different than the diet including mainly supplemented food. All diversity indices of food volume were higher in lowland localities compared to highland in all season’s cumulative sample. Similarity of the relative volume and relative frequency gradually decreased from spring to winter. Significant differences were found in wild boar consumption of roots (higher in A), grasses (higher in A), seeds and fruits (higher in B) and cereal husks (higher in B). Differences were also found in body mass of the piglets in A, as piglets were dominant group in both localities. Food supply of the localities and population management by the wildlife managers (supplemented food) were the main factors influencing the diet composition of the wild boar.     

Rainfall at African wintering grounds predicts age‐specific probability of haemosporidian infection in a migratory passerine bird

In migratory species breeding in temperate zones and wintering in tropical areas, the prevalence of blood parasites may be affected by migratory strategies and winter habitat choice. We explored whether African winter habitat was linked to the probability of haemosporidian infection in the House Martin Delichon urbicum breeding in Spain, and tested for potential differences between age‐classes. As a proxy for winter habitat features, we analysed stable isotope (δ²H, δ¹³C and δ¹⁵N) values of winter‐grown feathers moulted in tropical Africa. Rainfall at the African winter grounds was related to the probability of being infected with haemosporidians and this effect differed among age‐classes. We found that haemosporidian prevalence was similar for young and experienced birds wintering in habitats of higher rainfall (²H‐depleted), whereas there were great differences in winter habitats of lower rainfall (²H‐enriched), with young having a much higher prevalence compared with experienced birds. Likewise, experienced birds wintering in habitats of higher rainfall had a higher probability of haemosporidian infection compared with experienced birds wintering in habitats of lower rainfall. By contrast, young birds wintering in habitats of lower rainfall had a higher probability of haemosporidian infection compared with young birds wintering in habitats of higher rainfall. These outcomes highlight the interaction of age with haemosporidian infection in the migratory ecology of the House Martin, which may drive carry‐over effects in this long‐distance aerial insectivore.     

对鲇鱼鳃部寄生的固着鳋的生态研究

作者研究了江西江口水库鲇鳃部寄生固着鳋的种群生态学及其对寄生部位的选择性。固着鳋的感染率和丰盛度表现出明显的季节变化,以夏初最高;其繁殖也具有季节性,怀卵个体的比例同样有夏初最高。固着鳋对寄生部位的选择性似乎与种群的数量有关,当种群数量高时更多的固着鳋分布于中间的鳃片上,对多种寄生虫同时寄生条件下固着鳋寄生部位选择性的研究,将有助于进一步了解固着鳋和寄生鲇鳃部其它种类的寄生虫之间的关系。     

Epidemiology of toxoplasmosis in Chile. V. Prevalence of the infection in humans and domestic and wild animals, studied by indirect hemagglutination reaction, in the Juan Fernández Archipelago. V Region

A serological study utilizing an indirect hemagglutination test (IHAT) for toxoplasmosis was carried out in 222 humans and in 58 domestic animals (31 dogs, Canis familiaris; 27 cats, Felis catus), and in 62 wild mammals distributed into 50 rabbits, Oryctolagus cuniculus and 12 goats, Capra hircus. This survey was performed in the Juan Fernández Archipelago, formed by three islands: Robinson Crusoe, Santa Clara and Alejandro Selkirk (80 degrees 47'-78 degrees 47' west long., and 33 degrees 36'-33 degrees 47' south lat.). Blood samples were collected in filter paper and IHAT with titres greater than or equal to 1:16 were considered positive. This survey showed a prevalence of 42.3% in humans with no difference between men (43.0%) and women (41.5%). A high prevalence was found within groups of young individuals (0 to 19 years old), men and women. Regarding the domestic animal population, 44.8% resulted positive, distributed as follows: dogs 9.7% and cats 85.2%. Twenty one percent of wild animals were positive, distributed as follows: rabbits 8.0% and goats 75.0%. The global prevalence of toxoplasmosis in animals (domestic and wild) was 32.5%. All titres in humans and animals were less than or equal to 1:512. Toxoplasmosis is well extended among the human and animal population of the Juan Fernández Archipelago.     

High local species richness of parasitic wasps (Hymenoptera: Ichneumonidae; Pimplinae and Rhyssinae) from the lowland rainforests of Peruvian Amazonia

Abstract.  1. The parasitic wasp family Ichneumonidae (Hymenoptera) is of great interest because it has been claimed that its species richness does not increase with decreasing latitude.
2. No extensive studies of the family have been conducted in South American localities.
3. Arthropods were sampled using 27 Malaise traps in the Allpahuayo–Mishana National Reserve (56 000 ha) in the north-eastern Peruvian Amazonian lowland rainforest. The total duration of the sampling programme was 185 Malaise trap months.
4. Altogether, 88 species were collected. This is one of the highest local pimpline and rhyssine species numbers ever recorded. A comparison with results from Mesoamerica revealed that at equal numbers of individuals sampled, the number of Pimplinae and Rhyssinae species in Peruvian Amazonia is at least twofold compared with lowland locations in Mesoamerica and somewhat higher than in the most species-rich Costa Rican higher altitude localities.
5. Non-parametric methods of estimating species richness were applied. These suggest that additional sampling would yield a considerable number of new Pimplinae and/or Rhyssinae species.     

Validation and Application of Skeletochronology for Age Determination of the Ryukyu Ground Gecko,Goniurosaurus kuroiwae （Squamata： Eublepharidae）

Skeletochronology is a method commonly used for estimating the age of amphibians and reptiles in the wild. However, the number of lines of arrested growth （LAGs） does not necessarily reflect age in some species. We validated the applicability of this method to an endangered eublepharid gecko, Goniurosaurus kuroiwae, then inferred its longevity and age structures in wild populations. We classified young geckos into three groups using previously published data for early growth： Group 1 contained hatchlings before the first winter, Group 2 contained hatchlings after the first win- ter, and Group 3 included yearlings after the second winter. LAG numbers in these groups were then compared. All individuals in Group 1 possessed a single LAG, which was considered as a hatching line. Most individuals in Groups 2 and 3 possessed one and two additional LAGs, respectively （LAG1 and LAG2）, corroborating the notion that LAGs are formed annually. A few geckos exhibited fewer LAGs than expected. Analysis of variations in LAG and marrow cavity diameter demonstrated that in animals with fewer LAGs, endosteal resorption or fusion of hatching line and LAG1 had occurred. LAG2 was never lost by endosteal resorption and was identifiable by its diameter. Thus, the age of adult geckos could be determined by counting LAGs outward from LAG2. Application of this method to wild populations re- vealed that the longevity of this species is not less than 83 months, but that almost all individuals in fragmented habitats die before 50 months, suggesting lower population sustainability in such habitats.     

Differential infection of exotic and native freshwater amphipods by a parasitic water mold in the St. Lawrence River

A parasitic water mold (oomycete) of unknown origin was discovered infecting live native and exotic freshwater gammarid amphipods (Gammarus fasciatus and Echinogammarus ischnus, respectively) in the upper St. Lawrence River. Infections were associated with rapid die-offs of natural populations of amphipods, especially the exotic E. ischnus. Analysis of sequences of three different segments of the rRNA gene cluster indicated that the parasite was in the Saprolegniaceae family, and is related to other crustacean-associated Saprolegniaceae. Specific primers were designed based on the SSU rRNA gene and utilized for semi-quantitative analysis of parasite presence in live and dead amphipods. In laboratory experiments, infection prevalence was higher in E. ischnus individuals than in native amphipods. In addition, dead E. ischnus individuals exhibited more intense infections than G. fasciatus individuals. In contrast to the Great Lakes where E. ischnus has replaced G. fasciatus at many locations, the native species remains abundant in the St. Lawrence River more than a decade after invasion by E. ischnus in the late 1990s. We hypothesize that the parasite is facilitating the co-existence of the two amphipod species by reducing the abundance of E. ischnus in environments in which it might otherwise be dominant.     

Intestinal microsporidiosis in India: A two year study

Intestinal parasitic pathogens in HIV/AIDS patients include Cryptosporidium sp, Cystoisospora sp, microsporidia and less commonly other parasites. The two most common microsporidia causing intestinal infection are Enterocytozoon bieneusi and Encephalitozoon intestinalis. Most of the Indian studies for intestinal parasitic infections in HIV/AIDS patients have not included microsporidia, due to difficult staining and identification of the parasite. The aim of the present study was to find the prevalence of intestinal microsporidiosis and their species identification along with correlation of CD4 count with parasite positivity and diarrhoea in HIV positive individuals. Stool samples of 363 individuals including 125 HIV seropositive patients with diarrhoea, 158 HIV seropositive patients without diarrhoea, 55 HIV seronegative patients with diarrhoea and 25 healthy controls were obtained from various out-patient departments and in-patients admitted to a tertiary care hospital from August 2008 to October 2009. The stool samples were subjected to examination by wet mount, modified acid fast stain for coccidian parasites and multiplex nested PCR for microsporidia. The overall prevalence of all intestinal parasites among HIV patients in our study was 26.5%. The prevalence of intestinal parasitic pathogens in HIV positive patients with diarrhoea was 43.2%. Microsporidia were the most common parasites detected (14%) in all patients, while in HIV infected patients 15.9% patients had microsporidia infection. The most common species causing intestinal microsporidiosis in our study was E. intestinalis (10.5%). In HIV seropositive individuals with diarrhoea, E. intestinalis was 20.8% and E. bieneusi 8.0% while in HIV-seropositive individuals without diarrhoea, E. intestinalis was 3.8% and E. bieneusi 1.9%. E. intestinalis was present in 10.9% of HIV negative individuals with diarrhoea in whom E. bieneusi was not found. There was a significant association between CD4 count ≤ 200/μl and intestinal parasite positivity. Thus, it can be concluded that intestinal microsporidiosis is under reported but an important disease in India. The predominant species in our study is E. intestinalis , in contrast to other parts of the world where E. bieneusi is more common.     

大亚湾养殖鱼类寄生车轮虫的种类组成与季节动态

2017年8月至2018年7月对大亚湾8种养殖鱼类的车轮虫感染情况进行了调查, 采用Lom倡导的“统一特定方法”及Van As & Basson提出的“齿体定位描述法”对采获的车轮虫标本进行了形态鉴定与描述。结果在卵形鲳鲹(Trachinotus ovatus)、星点笛鲷(Lutjanus stellatus)、鞍带石斑鱼(Epinephelus lanceolatus)、眼斑拟石首鱼(Sciaenops ocellatus)和虎龙杂交斑[E. fuscoguttatus (♀) × E. lanceolatus (♂)]等5种鱼上共检获5种车轮虫: 亚卓车轮虫(Trichodina jadranica)、莱普斯车轮虫(T. lepsii)、长须鳠车轮虫(T. guliae)、劳牧小车轮虫(Trichodinella lomi)和斜拟车轮虫(Paratrichodina oblique); 其中卵形鲳鲹5种虫均有寄生, 虎龙杂交斑感染了4种虫, 星点笛鲷、眼斑拟石首鱼和鞍带石斑鱼分别感染了3种、2种和1种虫。周年感染数据表明: 5种虫的感染率均以卵形鲳鲹最高, 眼斑拟石首鱼上2种虫的感染率最低; 莱普斯车轮虫平均感染强度最高的宿主是虎龙杂交斑, 其他4种虫的均是卵形鲳鲹。寄生车轮虫的季节动态表明: 冬季的感染率和平均感染强度较低; 不同虫种感染高峰出现的季节不一, 其中斜拟车轮虫的感染高峰出现在秋季, 其春夏秋季的平均感染强度均大于其他4种虫。研究填补了大亚湾海区鱼类寄生车轮虫研究的空缺, 为该海区车轮虫病的诊断与防控提供了参考。     

Prevalence of ectoparasitic arthropods on wild animals and cattle in the Las Merindades area (Burgos, Spain)

This paper reports the prevalence of ectoparasitic arthropods in sampled groups of wild (n = 128; 16 species) and domestic (n = 69; 3 species) animals in the Las Merindades area of the Province of Burgos, Spain. The study revealed that wild animals were more infested and with a wider variety of ectoparasites than domestic animals. The parasitic prevalence was 67% for wild animals and 48% for livestock. In this way, 39% of animals were infected by ticks. Ixodes ricinus and Ixodes hexagonus were the most prevalent species whereas Dermacentor reticulatus showed affinity for the fox and wolf. The overall prevalence of parasitisation by fleas was 27%. Ctenophthalmus spp. showed the wider range host in wild animals, while Pulex irritans was the most frequent specie found. The parasitic prevalences by lice (Trichodectes melis, Trichodectes canis and Trichodectes mustelae) and by mite (Neotrombicula spp., Laelaps agilis and Sarcoptes scabiei) were 4% and 12%, respectively. In both cases only wild animals were found parasited.     

Seroprevalence of hantaviruses in small wild mammals trapped in South Korea from 2005 to 2010

The seroprevalence of Hantaan virus (HTNV) in wild rodents in South Korea was analyzed. Wild rodents were trapped in 18 cities in eight provinces during 2005-2007 and on three islands and four mountains during 2008-2010. Sera were collected from 629 out of 933 trapped wild animals and examined for immunoglobulin G antibodies to HTNV using indirect immunofluorescence assays. Apodemus agrarius (80.1%) was the most frequently captured species at almost all trapping sites. The overall prevalence of HTNV antibodies was 0.26 (162/629). Seropositive individuals were more frequent in cities (32.2%, n=410) than on islands (14.0%, n=57) or mountains (13.6%, n= 162). HTNV antibody-positive rate was higher in the fall (29.6%, n=253) than in the spring (23.1%, n=376). A. agrarius had the highest prevalence of HTNV antibodies (26.9%, n=561) of all tested species. Considering all the individuals, the prevalence of HTNV antibodies was higher in males (29.2%, n=250) than in females (22.3%, n=305). Our results show that HTNV is widely distributed throughout South Korea, and that HTNV infection of wild rodents is affected by their habitat, species, sex, and season.     

Carnivore population trends in Spanish agrosystems after the reduction in food availability due to rabbit decline by rabbit haemorrhagic disease and improved waste management

We conducted spotlight counts from 1992 to 2006 in 59 localities to describe carnivore presence, distribution and relative abundance in open agriculture lands in Aragon, northeastern Spain. During the study period, urban waste and carcases of domestic livestock became less available to wild animals, and rabbit (Oryctolagus cuniculus) abundance was low after rabbit haemorragic disease. We calculated a kilometric abundance index (KAI, individuals seen per 100 km surveyed) and the ratio between the number of positive localities in which a species was detected and the total of localities surveyed in a year. Indices to abundance and presence included: red fox (Vulpes vulpes), KAI per 100 km 10.70 and 100.0% localities per year; stray dog (Canis familiaris), KAI 0.48 and 22.6% localities; wildcat (Felis silvestris), KAI 0.10 and 19.1% localities; domestic cat (Felis catus), KAI 0.21 and 20.6% localities; polecat (Mustela putorius), KAI 0.02 and 2.0% localities; badger (Meles meles), KAI 0.16 and 23.6% localities; stone marten (Martes foina), KAI 0.11 and 19.6% localities; weasel (Mustela nivalis), KAI 0.002 and 0.6% localities; and genet (Genetta genetta), KAI 0.06 and 10.0% localities. Indices of badger abundance increased significantly, whereas indices of stray dogs decreased significantly over the study period. Abundance indices of red fox, the most important predator of small game, were stable throughout the study period. No significant trend was observed to other studied species. This study concludes that Aragon region maintains a diverse and rather stable carnivore community and shows that large scale data may help to identify trends of the more abundant wild and feral carnivores.     

Prevalence of Bordetella avium infection in selected wild and domesticated birds in the eastern USA

Bordetella avium is the etiologic agent of bordetellosis, a highly contagious upper respiratory disease of young poultry. Its prevalence among domesticated turkeys is well-known, but information on prevalence of this bacterium in other birds is limited. A survey of the prevalence of B. avium in wild and domesticated birds was conducted from June 1998 to January 2000, using tracheal cultures and serology. Of 237 blood samples from 61 species, 100 individuals from 41 species had antibodies against B. avium as determined with a microtiter agglutination test. Nine isolates of B. avium were cultured from 128 tracheal samples. Ribotype analysis of seven isolates from mallards (Anas platyrhynchos), one from a wild turkey (Meleagris gallopavo), and one from a Canada goose (Branta canadensis) indicated that they represent three strains, two of which were indistinguishable from clinical isolates from domesticated turkeys. Bordetella avium is present in wild bird populations of multiple species. Transmission from free-living avian populations to domesticated poultry populations may be possible and should be examined.