Setaria cervi (Filarioidea, Onchocercidae) undressing in ungulates: altered morphology of developmental stages, their molecular detection and complete sequence cox1 gene.

This work introduces new morphological and molecular information on the filaroid nematode Setaria cervi (Rudolphi, 1819) obtained from 13 infected game ungulates out of 96 dissected. The hosts comprised the following: a single moose (Alces alces), ten red deer (Cervus elaphus) and two sika deer (Cervus nippon) originating from the western and northern regions of the Czech Republic. Based on the complete sequences of the gene encoding mitochondrial cytochrome c oxidase subunit 1 (cox1), all 20 females and four males belonged to the species S. cervi. We detected three developmental female stages (adult fertile females, juvenile L5 females and L4 female larvae) differing in size and some morphological traits as the subtle structure of peribuccal crown and shape and features of tail knob. Such differences were described in detail for the first time. The phylogenetic relationships within the family Onchocercidae have been evaluated using new information on the cox1 sequence of S. cervi (maximum likelihood method, GTR + I + G model). In accordance with the latest phylogenetic studies, the present analysis confirmed the ancient separation of the subclass Setariinae from the remaining two onchocercid lineages Dirofilariinae and Onchocerinae.

Effects of excessive dietary zinc or zinc/cadmium and tapeworm infection on the biochemical parameters in rats.

The main objective of this study was to determine which biochemical blood parameters can serve as indicators of Zn or Zn/Cd burden and tapeworm infection. This study was performed on 44 Wistar male rats during a 6-week period, when rats were or were not fed a zinc/cadmium rich diet and were or were not infected with tapeworms (Hymenolepis diminuta). Total protein, albumin, urea, glucose, triacylglycerols, non-esterified fatty acids, cholesterol, alkaline phosphatase, aspartate aminotransferase, uric acid, Mg, Ca, P and Zn levels were analysed. Control rats with tapeworm infection had significantly higher (p ≤ 0.05) total protein, urea and phosphorus concentrations than did rats unaffected by any experimental factor. Rats given overdoses of zinc lactate exhibited significantly lower glucose levels than did the other rats, especially those infected with tapeworms. Low glucose level in uninfected rats indicate a Zn overdose; high doses of zinc lactate likely decrease levels of glucose via cortisol, which is released during stress. Rats fed the Zn/Cd hyperaccumulating plant Arabidopsis halleri and infected with tapeworms had significantly higher (p ≤ 0.01) cholesterol and urea levels but lower zinc, triacylglycerol, and alkaline phosphatase levels than did rats fed the same diet but free of tapeworms. The increase of alkaline phosphatase level in uninfected rats may indicate both Zn/Cd burden and rat liver damage. Overall, this study not only supports the theory that H. diminuta can serve as a promising model for helminth therapy of the host mammal but also confirmed that this tapeworm is capable to protect somehow the host organism from the harmful effects of heavy metals.

Long-term occurrence of Trichuris species in wild ruminants in the Czech Republic.

The aim of this study was to identify Trichuris species in wild ruminants from 32 localities in the Czech Republic using morphological and molecular methods (ITS1-5.8S RNA-ITS2 region polymorphisms). Trichurids were obtained from 176 wild ruminants (roe deer, sika deer, red deer, fallow deer and mouflons) that were culled between 2009 and 2017. Trichuris discolor is the predominant trichurid of all of the above-mentioned wild ruminants, whereas Trichuris ovis was identified less frequently in roe deer, fallow deer, sika deer and mouflons. Red deer were parasitised exclusively by T. discolor. Young hosts under 1 year of age were more intensively infected by trichurids than were adults (χ2 = 32.02, p = 0.00). Trichurid prevalence results obtained through coprological methods and those based on parasitological dissections differed significantly (χ2 = 16.26, p = 0.00). The regression analysis indicated that the eggs per gram (EPG) threshold (20 EPG) was exceeded only if the host was parasitised by more than 7 trichurid females. Full concordance between the positive results obtained by the coprological methods and those obtained via direct dissections was achieved when the number of trichurid females per host exceeded 51.

Reliable molecular differentiation of Trichuris ovis and Trichuris discolor from sheep (Ovis orientalis aries) and roe deer (Capreolus capreolus) and morphological characterisation of their females: morphology does not work sufficiently.

The main aim of the study was to evaluate associations between morphological variability of Trichuris females from sheep and roe deer and their rDNA polymorphism in whipworm populations from the Czech Republic. The results introduced the use of new molecular markers based on the internal transcribed spacer (ITS)1-5.8S RNA-ITS2 region polymorphisms, as useful tools for the unambiguous differentiation of congeners Trichuris ovis and Trichuris discolor. These markers revealed both parasites in roe deer and in sheep; however, T. ovis females predominated in sheep while T. discolor females occurred mostly in roe deer. Additional analysis of ITS1-5.8 rRNA-ITS2 discovered the genetic uniformity of the analysed T. discolor but high haplotype variation of T. ovis. Simultaneously, molecularly designated female individuals of both species were categorised into four morphotypes (MT) on the basis of morphology of genital pore area. MT1 and MT4 (vulvar opening on everted vaginal appendage/on visible cuticular bulge) occurred only in T. ovis, MT2 (uneverted vagina-vulvar opening without any elevation) was identified only in T. discolor and MT3 (transient type of vulvar opening on a small swelling) was observed in both species. Statistical analysis of biometric data confirmed that morphology of vulva is not a reliable marker for the species determination. On the basis of the ITS1-5.8S RNA-ITS2 region variability, we carried out a phylogenetic analysis (maximum likelihood method, Hasegawa-Kishino-Yano model) which showed that T. ovis haplotypes from the Czech Republic and Ireland and T. discolor haplotypes from the Czech Republic, Spain, Iran and Japan are sister OTUs.

Can the Hyperaccumulating Plant Arabidopsis halleri in Feed Influence a Given Consumer Organism (Rattus norvegicus var. alba)?

Zinc and cadmium concentrations in rat (Rattus norvegicus var. alba) tissues were analyzed by inductively coupled plasma optical emission spectrometry. Rats were fed the zinc and cadmium hyperaccumulating plant, Arabidopsis halleri. When compared to the control group, a Cd increase in all tissues (liver, kidneys, small intestine, spleen, testes, muscle), with the exception of bone tissue was observed. In comparison to the control group, the kidneys, liver and small intestine contained 375, 162, and 80 times more Cd, respectively. Differences between zinc concentrations in rats fed with A. halleri and those of the control group were significant only in the small intestine and kidney tissues. Results suggest using the hyperaccumulating plant A. halleri as a feed stresses the consumer organism not through its Zn content, but through its Cd content.

Is the tapeworm able to affect tissue Pb-concentrations in white rat?

The effect of gastrointestinal helminths on Pb accumulation in the host body is ambiguous. A laboratory experiment with Rattus norvegicus/Hymenolepis diminuta model was conducted to determine Pb toxicokinetics in a terrestrial host-parasite system. The ET-AAS or ICP-OES techniques were used to determine Pb concentrations (CPb) in both tapeworms and host tissues (kidney, liver, bone, testes, muscle and intestinal wall). Concerning the entire host-parasite system, the highest CPb were detected in H. diminuta. Rat kidneys and bone were the only two tissues whose mean Pb levels were lower in parasitized animals than they were in non-infected subjects after both levels of exposure. At low Pb exposure, parasitization slightly changed the Pb toxicokinetics in the host body. However, with respect to tissue at the same exposure level, no significant differences were detected between the parasitized and non-parasitized animals and no significant correlations were found between CPb in tapeworms and those of host tissues. The results of this study indicate that H. diminuta does not protect rat from elevated Pb exposure even if tapeworm accumulates a higher portion of ingested Pb dose compared with that of the most Pb-loaded host soft tissue. The portion of Pb dose accumulated in H. diminuta correlates positively with parasite biomass.

A 4-years monitoring of Hypoderma diana in horses from the Czech Republic.

The occurrence of Hypoderma diana (Diptera: Hypodermatidae) in a herd of 15 horses was observed during a 4-year period (2010-2013) in northwest Bohemia. During this period, infestation by the warble fly H. diana increased from 12.5% in 2010 to 53.3% in 2013. Nodules were observed on the neck, back, stomach, legs, and head. The incidence of H. diana was probably influenced by the presence of a specific host mouflon (Ovis orientalis musimon).

Effect of Pregnancy on Mercury Concentration in the Body of Free-living Small Rodents.

Relatively little information exists on the effects of mercury on terrestrial wildlife populations. We analyzed 38 free-living small rodent females (Myodes glareolus, Microtus agrestris, and Apodemus flavicolis), of which 11 were pregnant, for total mercury concentrations in combined liver and kidney samples. Using a single-purpose atomic absorption spectrometer for mercury determination, the measured mercury values ranged from 0.006 to 0.079 mg/kg. Pregnant females had significantly (P<0.041) higher mercury levels in liver and kidney than did nonpregnant females. Our results suggest that during mercury biomonitoring studies it is necessary to consider the pregnancy of the analyzed animals.

A revision of the trichostrongylid nematode Cooperia Ransom, 1907, from deer game: recent integrative research confirms the existence of the ancient host-specific species Cooperia ventricosa (Rudolphi, 1809).

The trichostrongylid roundworms of the genus Cooperia, which are important in veterinary medicine, currently comprise 19 valid species that parasitize the small intestine of both free-living and domestic ruminants. Only four Cooperia spp. have been reported in Europe, namely C. oncophora, C. punctata, C. curticei and C. pectinata. In 2018-2022, 25 red deer (Cervus elaphus) and 30 sika deer (Cervus nippon) of both sexes and various ages from several remote locations in the Czech Republic were parasitologically examined. Intestinal nematodes of the genus Cooperia were found only in two northern regions. Using the globally recognized key book on trichostrongylid nematodes, they were preliminarily identified as C. pectinata. However, a molecular analysis of cox2 and ITS rDNA gene sequences revealed that Cooperia sp. parasitizing Czech deer is a separate taxon that is more closely related to C. oncophora than to C. pectinata. A subsequent morphological analysis and literature survey confirmed the independence of deer Cooperia sp., which is similar but not identical to bovid C. pectinata. Previous long-term correct identifications of bovid C. pectinata and misidentifications of deer Cooperia species were caused by a fundamental error in the key book mentioned above. Interestingly, the ancient trichostrongylid nematode Strongylus ventricosus from the type host red deer (Cervus elaphus) shot near Greifswald (Germany) was described by Rudolphi in 1809. Rudolphi's type material (one male and four females) was deposited in the Museum für Naturkunde (Berlin). Later, the ancient species S. ventricosus was taken as a synonym for various Cooperia spp. Our current re-examination of the type male indicated that there is a relatively good agreement with our new material from Czech deer regarding the most important characteristics of S. ventricosus (i.e., the shape and size of the male spicules); however, Rudolphi's type material is in rather poor condition. The suggested resurrection of the deer Cooperia sp. in this study as Cooperia ventricosa (Rudolphi, 1809) requires verification by collecting and analyzing new nematode material from the type locality near Greifswald.

Corrigendum: A revision of the trichostrongylid nematode Cooperia Ransom, 1907, from deer game: recent integrative research confirms the existence of the ancient host-specific species Cooperia ventricosa (Rudolphi, 1809).

[This corrects the article DOI: 10.3389/fvets.2024.1346417.].

Trichomonas spp. in pigeons: detection by OSOM Trichomonas Rapid Test.

The efficacy of the OSOM Trichomonas Rapid Test (developed for rapid diagnosis of human Trichomonas vaginalis) in detection of Trichomonas spp. in pigeons (Columba livia) was investigated. Two oral cavity swabs were taken from 50 farm pigeons. Cultivation in Diamond Trichomonas medium was used as a reference method. According to a morphological determination, Trichomonas gallinae was the only protozoan found; however, no further molecular analysis was conducted. The OSOM Trichomonas test was positive in 39 oral swabs. In comparison with the cultivation method three samples were identified as false negative and one as false positive. Test specificity and sensitivity were established as 93% and 90%, respectively. Using Cohen's Kappa, the concordance between the two testing methods was found to be strong (kappa = 0.7506, 95% CI = 0.5162-0.9850). The OSOM Trichomonas test is not able to distinguish between Trichomonas species; however, results suggest that the test is suitable for the rapid detection of Trichomonas spp. infection in pigeons.

Cephenemyia stimulator and Hypoderma diana infection of roe deer in the Czech Republic over an 8-year period.

A survey of naso-pharyngeal and subcutaneous myiasis affecting roe deer (Capreolus capreolus) was conducted in the Czech Republic over an 8-year period (1999-2006). A total of 503 bucks and 264 does from six hunting localities were examined. The sampling area comprised predominantly agricultural lowlands and a mountain range primarily covered by forest. Since 1997, the deer have been treated each winter across the board with ivermectin (150 mg/kg, CERMIX® pulvis, Biopharm, CZ). Parasites found were the larvae of Hypoderma diana and Cephenemyia stimulator. There were no significant differences in warble fly infection among captured animals in the individual hunting localities. Overall, 146 (28.8%) of 503 animals (bucks) were infected with Cephenemyia stimulator larvae; body size of the second instar larva reached 13-18 mm. The prevalence ranged from 16.1 to 42.9% per year, and the mean intensity from 6 to 11 larvae per animal. Additionally, a total of 264 roe deer (does) were examined for H. diana larvae, and 77 (29.1%) were found to be positive; body size of the second instar larva reached 17 mm. The prevalence ranged from 18.8 to 50.0% per year, and the mean intensity from 13 to 22 larvae per animal. The results showed that the bot flies, Cephenemyia stimulator as well as H. diana, are common parasites in roe deer in the Czech Republic, and that through the help of treatment (ivermectin), it is possible to keep parasite levels low. The body weights of infected and non-infected H. diana deer did not differ significantly.

Significance of Intestinal Helminth Infection and Animal Sex for Mercury Concentrations in Two Rodent Species.

We compared the effects of animal gender, species, and intestinal helminth burden on mercury concentrations in rodents. Total mercury concentrations were determined in the liver and kidney tissues of 80 small rodents (44 yellow-necked mice, Apodemus flavicollis, and 36 bank voles, Myodes glareolus) captured in the Ore Mountains (northwest Bohemia, Czech Republic). Overall, 25/80 (32%) of animals were infected by intestinal helminths. The differences in mercury concentration between rodents infected and not infected with intestinal helminths were not statistically significant. Statistically significant differences in mercury concentrations were found only between voles and mice (that were not infected with intestinal helminths). This suggests the differences may be associated with host genetics. Apodemus flavicollis body tissues had significantly lower (P=0.01) mean Hg concentrations (0.032 mg/kg) than Myodes glareolus (0.279 mg/kg), provided that animals were not infected by intestinal helminths; if the animals were infected by intestinal helminths, the difference between both groups was insignificant. The effect of gender in this study was significant only for voles (without helminth infection); for mice (either with or without helminth infection) the differences between genders were not significant. Myodes glareolus males had significantly lower (P=0.03) Hg concentrations in liver and kidney tissues (0.050 mg/kg) than Myodes glareolus females (0.122 mg/kg). These results reveal the importance of considering species and gender when evaluating mercury concentrations.

Concentrations of Zn, Mn, Cu and Cd in different tissues of perch (Perca fluviatilis) and in perch intestinal parasite (Acanthocephalus lucii) from the stream near Prague (Czech Republic).

We monitored concentrations of Cd, Cu, Mn and Zn in acantocephalan parasites (Acanthocephalus lucii) and its final host (Perca fluviatilis). The concentrations in parasites were found to be significantly higher than those found in the muscle, gonads and liver of fish host. The bioaccumulation factor values (BF=C(parasite)/C(host muscle)) were 194, 24.4, 2.2 and 4.7 for Cd, Cu, Mn and Zn, respectively. This suggests a benefit for the host due to the high accumulation of toxic cadmium.

Effect of Acanthocephalus lucii infection on total mercury concentrations in muscle and gonads of fish host (Perca fluviatilis).

The samples from 13 perches (Perca fluviatilis) - muscle with skin and bones; fish gonads; and acanthocephalan parasites were analysed for mercury (Hg). Hg concentrations were present in all analysed samples. There were found no statistically significant difference in Hg concentration in fish tissues between perches either with or without infection by the acanthocephalan parasite, Acanthocephalus lucii). In this study there was no evidence that acanthocephalan worms accumulate mercury from hosts. For this reason, A. lucii is not a suitable bioindicator for mercury pollution.

Which McMaster egg counting technique is the most reliable?

This study focuses on the comparison of three selected modifications of the McMaster counting technique, namely the McMaster method modified by Wetzel (W) and Zajícek (Z), as well as the concentration McMaster technique according to Roepstorff and Nansen (R&N). These modifications differ in the weights of faeces examined (W, 2 g/Z, 1 g/R&N, 4 g), flotation solutions (W, NaCl/Z, MgSO(4) + Na(2)S(2)O(3)/R&N, NaCl + glucose), centrifugation (W, none/Z, 2,000 RPM for 2 min and 2,000 RPM for 1 min/R&N, 1,200 RPM for 5 min), number of McMaster chambers investigated (W, 3/Z, 2/R&N, 2), and multiplication factors used (W, 67/Z, 33/R&N, 20). To investigate the sensitivity and reliability of these methods, nematode eggs (Teladorsagia circumcincta) were used. Parasite elements are distributed through negative binomial distribution in naturally infected host faeces, and the number of parasite elements in a given amount of faeces sample is unknown to man. Therefore, we decided to prepare the exact number of eggs which were added to the parasite negative faeces; the faecal sample was then investigated. From this perspective, this is the first time a comparison of the McMaster methods has been so accurately investigated. This approach allows us to evaluate the real sensitivity and reliability of the tested method. As the findings of this study indicate, the highest sensitivity and reliability were obtained using the Roepstorff and Nansen modification. This McMaster modification is able to detect 20 eggs per sample (in 70% of samples). Concentrations of 200 and 500 eggs can be found in almost 100% of samples. Moreover, this method is simple, cheap and fast. For these reasons, we can recommend this method for routine veterinary practice.

Intestinal parasite Acanthocephalus lucii (Acanthocephala) from European perch (Perca fluviatilis) as a bioindicator for lead pollution in the stream "Jevanský potok" near Prague, Czech Republic.

Lead concentrations in the tissues of perch and its parasites were determined as mg/kg dw. Lead was found at higher concentrations in the acanthocephalans (11.56) than in different tissues (liver, gonads and muscle with skin and bone) of perch. With respect to fish tissues, the highest concentrations of lead were present in the liver (1.24), followed by the gonads (0.57) whereas the lowest concentrations were in the muscle with skin and bone (0.21). The bioconcentration factors for lead indicated that parasites accumulate metals to a higher degree than fish tissues--lead concentrations in acanthocephalans were 9.32, 19.27 and 55.05 higher than in liver, gonads and muscles of host, respectively.

Peptidases of pinworms Syphacia muris and Passalurus ambiguus.

In this first report about pinworms peptidases we primarily characterize peptidases released during in vitro maintenance of two common pinworms of laboratory animals -Syphacia muris and Passalurus ambiguus. The peptidase activity obtained using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) showed the presence of peptidases from S. muris with a wide range of molecular size (25-110 kDa), which degrades gelatin and mucin at alkaline pH levels. P. ambiguus released serine and aspartyl peptidases degrading gelatin at all tested pH (3, 5, 7, and 9) and at acidic pH Passalurus released aspartyl and cysteine peptidases which are active against mucin.

Influence of parasitism on trace element contents in tissues of red fox (Vulpes vulpes) and its parasites Mesocestoides spp. (Cestoda) and Toxascaris leonina (Nematoda).

Bioaccumulation of cadmium, chromium, copper, manganese, nickel, lead, and zinc in 56 foxes (Vulpes vulpes) and their parasites Mesocestoides spp. (Cestoda) and Toxascaris leonina (Nematoda) was studied. The levels of heavy metals were determined in the livers and kidneys of the animals depending on parasitism in the following ranges: Pb, 0.029-3.556; Cd, 0.055-9.967; Cr, 0.001-0.304; Cu, 4.15-41.15; Mn, 1.81-19.94; Ni: 0.037-0.831; Zn, 52.0-212.9 microg/g dry weight (dw). Cd in parasites (0.038-3.678 microg/g dw) were comparable with those in the livers of the host and lower than in the kidneys (0.095-6.032 microg/g dw). Contents of Pb, Cr, Cu, Mn, Ni, and Zn in cestodes were predominantly higher than those in the kidney and liver of the host. Median lead levels in Mesocestoides spp. (45.6 microg/g dw) were 52-fold higher than in the kidney and liver of the red fox (Vulpes vulpes) infected by both parasites and median Pb values in T. leonina (8.98 microg/g dw) were 8-fold higher than in the tissues of the parasitized red fox. Bioaccumulation factors of copper, zinc, nickel, and manganese are lower than those of lead and mostly range from 1.9 to 24 for Mesocestoides spp. and from 1.5 to 6 for nematode T. leonina depending on the tissue of host and element. A significant decrease in the content of Pb was found in the kidney of animals infected by T. leonina (0.260 microg/g dw) as well as those infected by Mesocestoides spp. (0.457 microg/g dw) in comparison with the lead content (0.878 microg/g dw) in the kidneys of the nonparasitized red fox. Regardless of a bioaccumulation of copper and manganese in the parasites, a significant increase of the concentrations of Mn and Cu was observed in the host's livers infected predominantly by Mesocestoides spp.

Effects of tapeworm infection on absorption and excretion of zinc and cadmium by experimental rats.

The main objective of this study was to determine how rat tapeworms affect the excretion of zinc and cadmium through rat feces. Male rats (Rattus norvegicus var. alba) were divided into four groups, and the experiment was conducted over a 6-week period. The control groups (00; 0T) were provided with a standard ST-1 rodent mixture and received 10.5 mg of Zn/week. Groups P0 and PT were fed a mixture supplemented with the hyperaccumulating plant Arabidopsis halleri at a dosage of 123 mg Zn/week and 2.46 mg Cd/week. Groups 0T and PT were infected with the rat tapeworm (Hymenolepis diminuta). Fecal samples were collected 24 h post exposure. Zinc and cadmium concentrations in rat feces were analyzed using inductively coupled plasma optical emission spectrometry. Tapeworm presence decreased the amount of metals excreted through the feces of the host throughout the entire experiment, with the exception of 1 week (control group). No statistically significant differences between zinc excretion rates in the control groups (00 and 0T) were detected at any time throughout the experiment. A statistically significant difference between zinc excretion rates (p < 0.05) in the exposed groups (P0 and PT) was detected in 2 of the 6 monitored weeks. Group PT excreted significantly less cadmium (p < 0.01) than group P0 did in three of the 6 weeks. Overall, our results indicate that tapeworms are able to influence the excretion of metals by their host. Tapeworms accumulate metals from intestinal contents. It is not clear whether tapeworms carry out this process before the host tissues absorb the metals from the intestines or the tapeworms accumulate metals excreted from the body of the host back to the intestines. Most likely, it is a combination of both phenomena.