Nematode assemblages indicate soil restoration on colliery spoils afforested by planting different tree species and by natural succession

Soil nematodes were studied in 28 afforested sites on clay colliery spoil from opencast mining in the Czech Republic. The afforestations had four replicate sites and were represented by 20–33-year-old plantations of oak, alder, linden, spruce, larch, pine, and sites left to natural succession. The total abundance of nematodes in deciduous plantations plus natural successions was 1156 × 10³ ind/m² and in coniferous plantations 1236 × 10³ ind/m². The abundance of plant parasites and omnivores was significantly greater in deciduous than in coniferous plantations. The abundance of root–fungal feeders dominated by Filenchus was greater in spruce and pine plantations than in deciduous plantations. Bacterivorous Plectus predominated in larch plantations. Nematode assemblages in deciduous plantations had significantly greater numbers of species and genera, H’gen, MI, ΣMI, EI and SI values, and greater proportions of omnivores plus predators to other trophic groups than the assemblages in coniferous plantations. The nematode fauna indicated most advanced soil restoration on spoils under oak and alder plantations, intermediate under linden and spruce, and least under pine and larch. Nevertheless, some nematodes typical for developed forests were either found in low population densities (e.g. Teratocephalus) or were missing (e.g. Malenchus).     

Morphological diagnosis of infective larvae of Libyostrongylus douglassii (Cobbold, 1882) Lane, 1923 and L. dentatus Hoberg, Lloyd and Omar, 1995 (Nematoda: Trichostrongylidae) of ostriches

The differentiation of the species of the Libyostrongylus genus is only possible with the obtainment of the adult parasites in the ostriches proventriculus and gizzard. The present work confirms that it is possible to differentiate the infective larvae of L. douglassii and L. dentatus allowing the differential diagnosis of these species by fecal culture. To show this, adult females from both species were collected from ten proventriculus from adult ostriches and separated by species. Both groups were macerated individually added to sterilized feces for standard fecal cultures. The infective larvae were recovered, identified, quantified and measured. All proventriculus analyzed were parasitized by Libyostrongylus spp. and a clear heterogeneous location for each species was observed. The infective larvae from the fecal cultures of macerated L. douglassii presented a mean total length of 874.3+/-33.80 microm, and a short sheath tail (29.5+/-4.11 microm) with acute termination. The infective larvae from the macerated L. dentatus presented mean total length of 856.0+/-43.63 microm, long sheath tail (61.2+/-9.52 microm) with filamentous termination. The mean measures of the tails of both species had a significant difference. The differentiation of the infective larvae of L. douglassii and L. dentatus by fecal cultures will facilitate the diagnosis of both species for further understanding the Libyostrongylus biology.     

Helminths of seven species of lacertid lizards from southern Africa

Two hundred and forty five lacertid lizards representing seven species (Heliobolus lugubris, Ichnotropis squamulosa, Meroles anchietae, M. cuneirostris, M. suborbitalis, Pedioplanis lineoocellata, P. namaquensis) from southern Africa were examined for helminths. Adults of one species of cestode, Oochoristica ubelakeri, and four species of nematodes, Maxvachonia dimorpha, Parapharyngodon rotundatus, Spauligodon smithi, Thubunaea fitzsimonsi and metacestodes of a cyclophyllid cestode, the nematodes, Abbreviata sp. and an undetermined ascarid species, and an acanthocephalan species (as cystacanths) were found. Mean helminth species richness for adult helminths was 2.4 ± 1.3 S.D. (range = 1–4 per host species).     

Geographical variations in infection by larval Anisakis simplex and Contracaecum osculatum (Nematoda, Anisakidae) in walleye pollock Theragra chalcogramma stocks off Hokkaido, Japan

ABSTRACT: Stocks of walleye pollock Theragra chalcogramma collected from: (i) the Sea of Japan (off Rebun Island and Kumaishi); (ii) the Pacific coast (off Shikabe and eastern Hokkaido); and (iii) Nemuro Strait off Hokkaido, northern Japan, were examined for anisakid nematodes during December 1999 to February 2000, and the prevalence and abundance of Anisakis simplex and Contracaecum osculatum larvae were compared among the various sampling sites for fish of the same size and age. Anisakis simplex was generally more abundant than C. osculatum . Infection by A. simplex varied between the aforementioned stocks of walleye pollock as well as within stocks, whereby fish from off Rebun Island and Nemuro Strait were infected the most, followed by those from off the Pacific coast and Kumaishi. Infection by C. osculatum differed between the host stocks, and C. osculatum was the most abundant among the fish from Nemuro Strait. The infection variations seemed to be due to differences in host growth rate, host feeding habit, and the distribution of marine mammal final hosts. The results indicate that these two larval nematodes are useful biological indicators for the population study of walleye pollock in Japanese waters.     

Occurrence of anthelmintic resistant equine cyathostome populations in central and southern Italy

In the present survey, 276 horses bred on 16 farms located in central and southern Italy were investigated for the presence of drug resistant cyathostomes by a Fecal Egg Count Reduction Test (FECRT). Sixteen to 20 animals were selected on each farm and randomly assigned to one of four equally sized treatment groups. Groups were treated with fenbendazole, pyrantel pamoate, ivermectin or moxidectin. Resistance to fenbendazole was declared on six farms (37.5%) and suspected in two farms (12.5%), with FECR values ranging from 41% to 88.3%. Resistance to pyrantel was found in two farms (12.5%) and was suspected in one case (6.2%), with FECR values ranging from 43% to 85.4%. Macrocyclic lactones remained effective on all farms. Only cyathostome third stage larvae (L3) were found in fecal cultures after treatment. This paper reports the first wide survey conducted in Italy for anthelmintic resistance in equine cyathostomes. The results indicate that multiple drug resistant equine cyathostomes are present in the central and southern regions of Italy. These data call for a geographically and numerically broader investigation of horse farms in all regions and for the development and implementation -among veterinarians, owners and managers of a plan to reduce the expansion of these anthelmintic resistant populations and control these important parasites.     

Intestinal and haematic parasitism in the birds of the Almuñecar (Granada, Spain) ornithological garden

Birds from the Almuñecar ornithological garden (Granada, Spain) were surveyed from June 2006 to May 2007 to establish programmes to prevent, control, and treat intestinal and haematic parasites. A total of 984 faecal samples and 41 samples of blood were collected from Psittacidae, Cacatuidae, Phasianidae, and Anatidae. One or more intestinal parasites were identified in 51.6% of the samples. Blood parasites were found in 26.8% of the birds examined. The most frequent pathogenic endoparasites were coccidians, such as Cyclospora sp. (4.5%), Eimeria sp. (4.1%) and Isospora sp. (2%) and helminths such as Capillaria sp. (10. 1%), Ascaridia sp. (4.9%) and Heterakis gallinarum (4.9%). All the parasites varied with season but the most were found year round. Multiple parasitic infections by intestinal parasites were common, with 196 of 984 faecal samples having 2–5 intestinal parasites. The most frequent cases of multiple parasitism were Blastocystis plus Entamoeba sp. and Blastocystis plus Cyclospora sp. The haematic protozoa detected were Haemoproteus sp. (17%) and Plasmodium sp. (7.3%). Multiple parasitism by Haemoproteus sp. and Plasmodium sp. was detected in 1 sample of Gallus gallus. After each sampling, some of the affected animals were treated according to our results, and the corresponding programmes of prevention and control were designed.     

Nematode feeding and activity: the importance of development stages

Summary Nematodes have four juvenile stages and there is significant growth during development. The stages may differ in their respiratory and metabolic rates, and one stage may have significantly greater resistance to environmental stress. The mode of life of successive stages may vary from migratory to sessile. In both the Diplogasterida and Mononchida initial stages may be bacterial-feeding and later stages predatory on protozoa or nematodes. If the role of nematode species in promoting mineralization of nutrients is to be fully understood it is necessary to determine the trophic and metabolic characters of each stage under field conditions.Dedicated to the late Prof. Dr. M.S. Ghilarov     

Predator–prey interaction in soil food web: functional response, size-dependent foraging efficiency, and the influence of soil texture

In a series of laboratory experiments, we presented carnivorous Macrobiotus richtersi (Tardigrada, Macrobiotidae) with nematode prey to assess their importance as predator. We investigated consumption rate for (a) different prey densities (10–400 prey individuals), (b) different prey biomasses (22–80 ng), (c) different prey species (Pelodera teres, Rhabditidae, versus Acrobeloides nanus, Cephalobidae) and (d) different environments (2-D agar surface versus 3-D sand fractions of three different textures). M. richtersi consumed up to 4.6 g nematode prey in 4 h, that is, 43% of the tardigrades body mass. Predation rate was positively correlated with prey density. The optimal prey in the present investigation was the biggest prey because it yielded the highest biomass uptake per time. In addition, the size of M. richtersi played an important role in consumption rate. Bacterivorous nematodes reacted differently to attack. Even in a water film on stiff agar where nematode agility was limited, a vigorous undulation reaction of P. teres led to a measurable reduction in consumption rate. A. nanus, in contrast, showed little response to attack. Microcosm experiments with sands of different particle size demonstrated that M. richtersi is able to chase and consume small bacterivorous nematodes in a 3-D soil matrix. However, consumption rate in sand microcosms was significantly reduced compared with pure agar. The sand matrix improved nematode agility and possibly provided small pores as refuge for the nematodes. The lowest consumption rate was observed in fine sand. Effects of predatory tardigrades on nematode numbers in the field are discussed.     

Characterization and vector relation of a serologically distinct isolate of tobacco rattle tobravirus (TRV) transmitted byTrichodorus similis in northern Greece

A virus isolated from diseased tobacco plants growing in Macedonia, northern Greece, had host range and physico-chemical properties typical of a tobravirus. Although it was serologically unrelated to any of the ten tobravirus isolates tested, it reacted in spot hybridization tests with a probe derived from RNA-1 of tobacco rattle virus (TRV) strain SYM. Therefore, the isolate probably represents a previously undescribed serotype of TRV. Male, female and juvenileTrichodorus similis nematodes recovered from the rhizosphere of the diseased tobacco plants transmitted TRV in each of three laboratory experiments. In two of these experiments 50% and 54%, respectively, of the nematodes transmitted virus toPetunia hybrida bait plants, whereas only 18% transmitted virus toNicotiana tabacum plants in a third test. Ultrathin sections of the feeding apparatus of individual nematodes, which had transmitted virus, were examined by electron microscopy. Virus particles were observed, retained as a monolayer in the apices of the oesophageal lumen and as a group of particles within a matrix in the open part of the lumen.     

Two new records of helminth parasites of domestic cat from Uruguay: Alaria alata (Goeze, 1782) (Digenea, Diplostomidae) and Lagochilascaris major Leiper, 1910 (Nematoda, Ascarididae)

Eight helminth taxa were recovered from the necropsy of four stray domestic cats from Colonia Miguelete, county of Colonia, Uruguay. Two of them are recorded for the first time for domestic cats in that country: Alaria alata (Goeze, 1782) from the small intestine (which is also the first trematode species found in domestic cat in Uruguay), and Lagochilascaris major Leiper, 1910 from the pharynx. The remaining helminth species found were Toxocara mystax (Zeder, 1800) and Spirometra sp. from the small intestine, Trichuris serrata (von Linstow, 1879) from the caecum, Eucoleus aerophilus (Creplin, 1839) from the trachea, and Pearsonema feliscati (Diesing, 1851) from the urinary bladder. Moreover, four female specimens of an unidentified Spiruroidea were collected from the stomach and small intestine of one host.