Helminthologia

Năng suất sản xuất trứng của Fasciola gigantica (chủng Nhật Bản) được ước tính dựa trên dữ liệu đếm trứng thu được từ việc nhiễm thử nghiệm hai con dê. Hai con dê này được tiêm nhiễm với một liều duy nhất 50 metacercariae. Con dê đầu tiên được khám nghiệm tử thi 132 ngày sau khi nhiễm (NSK) và con dê thứ hai 732 NSK. Sau khi xuất hiện, sản phẩm phân hằng ngày được thu thập và cân lên và số lượng trứng trên mỗi gam được đếm. Khi khám nghiệm tử thi, 23 ký sinh trùng được thu hồi từ gan của con dê đầu tiên, và 5 từ con dê thứ hai. Số lượng trứng trung bình sản xuất mỗi ngày trên mỗi ký sinh trùng (± giới hạn tin cậy 95%) là 9.477,9 (± 764,92) cho dê đầu tiên từ 106 đến 132 NSK, và 8.064,1 (± 416,49) từ 195 đến 561 NSK cho dê thứ hai. Số lượng trứng sản xuất mỗi ngày trên mỗi ký sinh trùng ở Fasciola gigantica (chủng Nhật Bản) đã đạt đến các giá trị dao động từ khoảng 8.000 đến 10.000 trứng.

The helminth fauna of weatherfish (Misgurnus fossilis) in natural range is reviewed. Several helminth species reported in weatherfish are discussed with reference to host specificity and their geographical distribution. The current list of helminth parasites of the weatherfish includes 37 species. Most (15) are digenean trematodes, half of them being larval stages. Only one species of trematode — Allocreadium transversale is more specific parasite of weatherfish. Second largest group are Monogenea, with 10 species. Two of them (Gyrodactylus strelkovi and G. misgurni) are found only in the genus Misgurnus. Tapeworms (6 species) and Nematodes (6 species) are less numerous. No Acanthocephala, however, were ever found.

The aim of the study was to compare helminth community structure of urban and forest blackbird populations. 24 helminth species in 98 blackbirds were found. Higher species richness was noted in the forest population of the blackbird (23 species) in comparison to the urban population (14 species). The response of the helminth fauna to a synanthropic habitat, contrary to a natural habitat, consists in a significant reduction in most parasitological parameters. Higher species richness has been noted in spring (17 species) than in autumn (14 species). Urban habitat, in contrast to the forest, may cause changes in the abundance of helminth communities in male and female blackbirds. The helminth fauna of nestlings, in spite of low species richness is characterized by a higher prevalence and intensity of infection in comparison to blackbirds feeding on their own. Helminth fauna of the blackbird seems to be a good indicator of environmental quality.

Parasites have been recognized as indicators for natural or man-induced environmental stress and perturbation. In this article, we investigated the role of two non-exclusive hypotheses on the response of helminths of wood mice to fire perturbation: 1) a reduction of the helminth infracommunity (species richness) in post-fire areas due to the temporal lack of worms with indirect (complex) life cycles linked to intermediate hosts that are more specialized than the final host, and 2) an increase of the abundance of helminths with direct (simple) life cycles as a response of increasing abundances of the final host, may be in stressful conditions linked to the post-fire recolonization process. We studied the helminth infracommunities of 97 wood mice in two recently burned plots (two years after the fire) and two control plots in Mediterranean forests of NE Spain. Species richness of helminths found in control plots (n = 14) was twice large than in burned ones (n = 7). Six helminth species were negatively affected by fire perturbation and were mainly or only found in unburned plots. Fire increased the homogeneity of helminth infracommunities, and burned plots were characterised by higher dominance, and higher parasitation intensity. We found a gradient of frequency of occurrence of helminth species according to life cycle complexity in burned areas, being more frequent monoxenous (66.6 %), than diheteroxenous (33.3 %) and triheteroxenous (0 %), confirming the utility of helminths as bioindicators for ecosystem perturbations. Despite the short period studied, our results pointed out an increase in the abundance and prevalence of some direct life cycle helminths in early postfire stages, whereas indirect life cycle helminths were almost absent. A mismatch between the final host (that showed a fast recovery shortly after the fire), and the intermediate hosts (that showed slow recoveries shortly after the fire), was responsible for the loss of half of the helminth species.

Seven flocks of different composition of goat and/or sheep were evaluated for the presence of Muellerius capillaris (Mueller 1889) in sites of different climatic conditions and under different management practices in northwestern Argentina. The nematode was recovered and identified in four goat flocks and two mixed goat and sheep flocks. Three goat flocks and both mixed goat and sheep flocks were located in Lerma Valley (Salta), with the other goat flock located in Quebrada de Humahuaca (Jujuy). M. capillaris was not detected in the Puna of Jujuy (3500 m a.s.l.). First-stage larvae were recovered from fecal samples using the Baermann technique. Lungs from six goats revealed numerous small pulmonary nodules and areas of emphysema, as well as a small number of M. capillaris adults. This is the first report of M. capillaris in Argentina.

Anthropogenic disturbance associated with clear-cutting and changing the environmental landscape can lead to distinct microhabitat structure surrounding aquatic habitats. The transmission dynamics of trematode parasites in their snail first intermediate hosts were examined to determine if these alterations affect trematode parasite distribution. This was accomplished by examining 2,771 pulmonate snails belonging to two species (Physa gyrina and Lymnaea columella) over a three month period in a pond surrounded by distinct microhabitats as a result of anthropogenic changes to the environmental landscape. Trematode parasite distribution in the snail first intermediate hosts was largely tied to the microhabitat preference of their vertebrate definitive hosts. Autogenic species were found further away from the center of the open microhabitat and allogenic parasites were closer to the centralized point, most likely as a result of habitat preference by their frog and waterfowl definitive hosts, respectively. Additionally, there was increased parasitism in the molluscan hosts at the edges of the wooded environments due to habitat overlap of autogenic and allogenic species hosts, indicating that microhabitat structure can have profound effects on parasite distribution.

In this paper, the occurrence and new morphological data of Unilatus unilatus Mizelle et Kritsky, 1967 from the gills of Hypostomus strigaticeps (Regan, 1907), Hypostomus regani (Ihering, 1905), and Hypostomus iheringii (Regan, 1908) from the Chavantes reservoir, São Paulo State, Brazil are reported. Unilatus unilatus from this reservoir presents differences in relation to the holotype previously described such as, eggs with no bifid or trifid filament and a rounded termination, anterior bar slightly curved with a posterior projection, and posterior bar which may present three shapes. This is the first record of U. unilatus in southeastern Brazil outside the Amazon River Basin, with H. strigaticeps, H. regani and H. iheringii as new hosts.

The presence of Echinococcus sp. cysts was investigated in 822 sheep, 123 goats and 112,521 cattle from Lombardy region, North Italy. Faecal samples from 40 sheepdogs were also analyzed, with 9 samples containing taeniid eggs (22.5 %), 8 samples being coproantigen-positive (20 %), and one dog from a northern province (Lecco) positively confirmed by PCR. Cystic Echinococcosis (CE) was detected in 0.36 % of sheep and in 0.29 % of cattle in 2004. No goat resulted to be infected. Data from CE patients treated in Lombardy were collected by inspecting hospital discharge records. In 2004, 156 CE-related admissions (62 % male and 38 % female) were reported in Lombardy. Total hospital stay was 1,372 days (1,286 for inpatients, 86 for outpatients). Most patients (72.4 %) were residents in Lombardy and 1.9 % were from Piedmont; the remaining patients were from central and southern Italy. According to acquired data CE resulted hypoendemic in animals in Lombardy. Prevalence rates in humans were higher than expected in this region, usually considered as non-endemic. Assessment of the prevalence of CE in humans remains a difficult, costly, time-consuming and labourintensive task. The present study suggests establishing a National Registry of Cystic Echinococcosis with the aim to highlight regional risk factors and to benefit from its matching both clinical and epidemiological data.

The study was focused on a role of lymphocytes and macrophages in the immune response of mice to Trichinella spiralis infection with low (10) and high (400) infective doses of larvae. The light infection stimulated the proliferation of splenic T lymphocytes only during the intestinal phase of the infection, till day 15 post infection (p.i.), but the heavy infection activated T cells during the migration of newborn larvae (from day 20 to 30 p.i.). B cell proliferation was markedly stimulated after the heavy infection. The light infection increased the presence of helper CD4 cells till day 10 p.i. in contrast to the heavy infection, but subpopulation of CD8 T cells was not influenced by a different size of infective dose. Cytokine production of IL-5 and IFN-γ was not markedly affected by the light infection in contrast to the heavy infection that stimulated IL-5 synthesis during the whole experiment and IFN-Γ during the migration of newborn larvae. The light infection stimulated a metabolic activity of peritoneal macrophages already in the intestinal phase, but the heavy infection affected their activity only in the muscle phase of the infection.

Suppressiveness of soil amendments with different rates of composted biowaste materials, olive pomace, municipal green wastes, sewage sludge and spent mushroom substrate, was evaluated against the root-knot nematode Meloidogyne incognita on tomato in potting mixtures. Soil amendments were applied at 0, 10, 25, 50 and 100 g kg−1 soil, according to a randomized block design with five replications for each treatment. Sixty days after tomato transplanting, nematode population density on plant roots and in soil and root gall infestation were assessed on each root system, and plant top and root weight were also recorded. Soil pH, dry and organic matter content, total and ammoniacal nitrogen were analyzed at the same time. Olive pomace-based composts resulted in the highest nematode suppression (73–97 %, according to the rate) and significantly reduced gall formation on tomato roots. Olive-waste compost affected positively tomato growth only in combination with sheep wool wastes, but it caused phytotoxicity when mixed with chicken manure and urea. Soil amendments with composted mushroom substrate also provided a consistent nematode suppression and a significant increase of plant growth, whereas composted municipal green wastes were more suppressive and positively affected tomato growth when combined with sewage sludge. Soil chemical parameters were scarcely affected by compost amendments, as organic matter was significantly increased only by the olive pomace-derived composts and nitrogen content only at the highest rate of the five composts. Data from the experiment confirmed the potential of compost amendments for sustainable management of root-knot nematodes both in field and greenhouse container media, though their technical effectiveness and economic convenience are strictly dependent on a correct proportion and local availability of raw materials used in the composting process.