Trichinella Larvae Research Articles

RESEARCH INTO THE ROLE OF BIVALVE MOLLUSKS IN THE PREVALENCE OF TRICHINELLA IN MARINE BIOCENOSES

Trichinosis is a dangerous anthropozoonotic disease caused by a nematode of the genus Trichinella. Being polyhostal, Trichinella is recorded in more than 150 species of animals, including marine mammals. While the circulation mechanism in terrestrial animal species is well-studied and has a logical explanation, the ways of infection of marine mammals remain unexplored in many respects up to the present. Among marine mammals, trichinosis is most common in walruses with the prevalence of 1.5% (Bukina L.A., 2015). The main sources of trichinosis infection for benthophagous walruses are probably their most important prey items, amphipods and bivalve mollusks. The purpose of the present paper was to study the role of bivalves in the transmission of infective material to a potential host. In the experimental infection, decapsulated trichinella larvae isolated from the muscle tissue of cage-kept arctic foxes were used. Trichinella larvae were isolated by the method of trichinelloscopy and digestion of muscle tissue in artificial gastric juice. It was found that the filter feeding structure of mussels does not let trichinella pass into the intestine. However, larvae trapped in the mantle cavity are filtered out and removed as pseudofaeces through the excurrent siphon to the environment. At the same time, they remain viable for 113 hours. The most invasive and viable were trichinella isolated from pseudofaeces and wash off from the mantle cavity (mantle complex) within 30 to 70 hours. The bio-assays performed on white outbred mice were positive. Therefore, mussels can be direct or indirect sources of the invasion. Taking into account that walruses can eat more than 3,000 mollusks in one feeding, the probability of infection increases significantly.

STUDY OF TRICHINELLA INFECTION IN WILD MAMMALS IN THE KURSK REGION

In the territory of the Kursk region, according to official statistics, trichinosis in humans is extremely rare, mainly in the form of imported cases. However, sometimes cases of the disease are detected among the population, which are associated with trichinella infection when eating meat of wild mammals living in the natural biocenoses of the Kursk region. In this regard, the purpose of our study was to study the infection of wild animals with Trichinella in the Kursk region. Trichinella larvae were identified by the method of compressor trichinelloscopy and the method of digestion of muscle tissue in artificial gastric juice. Capsule-forming larvae of Trichinella (Trichinella spp.) were found in the muscles of animals. Trichinella was found in the stone marten (10,5%), polecat (6,7%), red fox (5,9%), raccoon dog (22,2%) and white-breasted hedgehog (5,3%). Earlier, we conducted studies that showed that in the Kursk region, Trichinella parasitize not only in carnivores and insectivores, but also among rodents and wild boars. High rates of infection in predators indicate a wide spread of Trichinella in natural biocenoses of the Kursk region. This creates an actual risk for people to be infected with Trichinella. This risk is especially significant for family members of hunters, their relatives and friends.

High prevalence, intensity, and genetic diversity of Trichinella spp. in wolverine (Gulo gulo) from Yukon, Canada

BackgroundSpecies of Trichinella are globally important foodborne parasites infecting a number of domestic and wild vertebrates, including humans. Free-ranging carnivores can act as sentinel species for detection of Trichinella spp. Knowledge of the epidemiology of these parasites may help prevent Trichinella spp. infections in northern Canadian animals and people. Previous research on Trichinella spp. in wildlife from Yukon did not identify risk factors associated with infection, or the diversity and identity of species of Trichinella in regional circulation, based on geographically extensive sampling with large sample sizes.MethodsIn a cross-sectional study, we determined the prevalence, infection intensity, risk factors, and species or genotypes of Trichinella in wolverine (Gulo gulo) in two regions of Yukon, Canada, from 2013–2017. A double separatory funnel digestion method followed by mutiplex PCR and PCR-RFLP were used to recover and identify species of Trichinella, respectively.ResultsWe found larvae of Trichinella in the tongues of 78% (95% CI 73–82) of 338 wolverine sampled. The odds of adult (≥ 2 years) and yearling (1 year) wolverine being Trichinella spp.-positive were four and two times higher, respectively, compared to juveniles (<1 year). The odds of Trichinella spp. presence were three times higher in wolverine from southeast than northwest Yukon. The mean intensity of infection was 22.6 ± 39 (SD, range 0.1–295) larvae per gram. Trichinella T6 was the predominant genotype (76%), followed by T. nativa (8%); mixed infections with Trichinella T6 and T. nativa (12%) were observed. In addition, T. spiralis was detected in one wolverine. Out of 22 isolates initially identified as T. nativa in multiplex PCR, 14 were analyzed by PCR-RFLP to distinguish them from T. chanchalensis, a recently discovered cryptic species, which cannot be distinguished from the T. nativa on multiplex PCR. Ten isolates were identified either as T. chanchalensis alone (n = 7), or mixed infection with T. chanchalensis and T. nativa (n = 2) or T. chanchalensis and Trichinella T6 (n = 1)].ConclusionsWolverine hosted high prevalence, high larval intensity, and multiple species of Trichinella, likely due to their scavenging habits, apex position in the food chain, and wide home range. Wolverine (especially adult males) should be considered as a sentinel species for surveys for Trichinella spp. across their distributional range.Graphical

Influence of azoxymer bromide on the cellular composition of the spleen in experimental infection of T. spiralis

The experiment used white mice, which were divided into 4 groups. The first group of mice was injected with a saline solution with 0.04 mg of Trichinella antigen obtained by the Magat method subcutaneously, the second group of mice was injected with azoxymer bromide (polyoxidonium) at a dose of 0.004 mg/mouse, the third group was infected with Trichinella larvae without preliminary administration of drugs, group 4 served as a control. A week after the last injection of drugs, mice were infected with invasive Trichinella larvae at a dose of 40 larvae/animal. Evaluation of the protective properties of polyoxidonium in laboratory models was carried out by determining the intensity of invasion in studies of all muscle groups of the animal by the method of peptolysis and histological material to assess the cellular composition of the spleen. The protective effectiveness of polyoxidonium was 99.43%. The rearrangement of the structure of the spleen under the influence of an immunostimulant indicated a high degree of reactivity of the spleen of animals in response to the introduction of polyoxidonium (the ratio of red and white pulp and their cellular composition changes).

The study of persistence of microorganisms and parasites in food products

Safety of food products is assessed by hygiene standards, which include biological, chemical and physical risk factors. Biological risk factors include viruses, bacteria, mold and yeast fungi, protozoa, helminths and their toxins. Their presence in food products is either completely unacceptable, or should not exceed the acceptable ranges of concentrations in a certain volume of the test products. The original scoring technique was used for a quantitative assessment of biological risks. The persistence of microorganisms and helminthes was evaluated in meat, dairy and vegetable products, culinary products, eggs, canned food, pickles and marinades. Among the studied biological risk factors, the following have very low persistence in food products: adolescari of Fasciola spp.; eggs of Trichocephalus trichiuris, Enterobius vermicularis, Hymenolepis nana, Echinococcus spp., Ascaris lumbricoides, Strongyloides stercoralis larvae, cysts of Lamblia intestinalis, Entamoeba histolytica. Low persistence was demonstrated by Rotavirus, hepatitis A virus, the genus Norovirus, bacteria of the Leptospira spp. and Vibrio spp., Escherichia coli, Toxoplasma gondii and Cryptosporidium parvum. Medium persistence was demonstrated by plerocercoids of Diphyllobothrium spp, cysticercuses of Taeniarhynchus saginatus and Taenia solium, bacteria Shigella spp. and Francisella tularensis. High persistence was shown by larvae of the genus Trichinella, metacercaria Opisthorchidae, bacteria Mycobacterium spp., Proteus spp., Campylobacter spp., Yersinia spp., Brucella spp., Bacillus cereus, Clostridium perfringens, Staphylococcus aureus and Clostridium botulinum. Aphthovirus, Salmonella spp. and Listeria monocytogenes have very high persistence.

Influence of chemically and biosynthesized silver nanoparticles on in vitro viability and infectivity of Trichinella spiralis muscle larvae.

Trichinellosis is a serious worldwide parasitic zoonosis. The available therapy for the treatment of Trichinella spiralis is not satisfactory. Therefore, the recovery of effective treatment is required. This work aimed at evaluating of the in vitro effect of silver nanoparticles (AgNPs) on muscle larvae of Trichinella. The present study investigated the larvicidal properties of chemical and myrrh AgNPs on muscle larvae (ML) of T. spiralis. The used AgNPs were chemically prepared using NaBH4 as reducing agent and biosynthesized using methanolic myrrh extract. Characterization of synthesized AgNPs was monitored via UV-vis spectrophotometry, Fourier transform infrared spectroscopy and transmission electron microscopy (TEM) studies. The ML incubated with AgNPs at concentrations ranged from 1 μg/ml to 20 μg/ml. Chemical and biosynthesized AgNPs revealed marked larvicidal effect against ML of Trichinella. Additionally, this in vitro study showed degenerative changes affecting the cuticle of AgNPs treated ML. The effectiveness of AgNPs on the infectivity of Trichinella ML was also assessed. The results showed complete inhibition of the infectivity of ML exposed to sublethal doses of chemical and myrrh prepared AgNPs when used to infect animal models. This is the first report where myrrh synthesized AgNPs have been tested for their anthelminthic activity against Trichinella in an in vitro model.

Serological Detection of Trichinellosis among Suspected wild Boar Meat Consumers in North and Northeast of Iran

Background:Trichinellosis is a foodborne zoonosis disease worldwide. Humans acquire infection by ingesting raw or uncooked animal flesh containing viable Trichinella larvae. The most common reservoirs of this helminth are pigs and wild boars. In northern Iran, hunting and consuming wild boars meat by some communities, including ethnic Armenians, may expose them to trichinellosis. Here, we investigated anti-Trichinella IgG antibodies in high-risk individuals in northeastern Iran.Methods:From Mar to Aug 2020, we collected 189 blood samples from individuals with a history of wild boar meat consumption and examined the sera for anti-Trichinella IgG antibodies using a commercial ELISA kit (NovaTec Immunodiagnostica GmbH, Germany). Sera from 30 individuals with no history of eating wild boar meat was used to determine the range of actual negative values and possible cross-reactivity with other similar antigens.Results:Of the 189 participants, 5 (2.6%) had anti-Trichinella IgG antibodies (OD, 1.176 ±0.154). None of the 30 negative controls became positive (OD, 0.198 ± 0.044). The age, gender, occupation, and education showed no significant association with Trichinella seropositivity rate (P>0.05). All five seropositive cases were among 112 individuals (4.46% seropositivity) that resided in the western part of the study area, stretching from Behshar to Gorgan.Conclusion:Eating wild boar meat might expose individuals to trichinellosis in the north and northeast of Iran. Further studies with more individuals from different parts of the country and confirmation of the ELISA by additional tests like Western blot will give a more in-depth insight into human trichinellosis epidemiology in Iran.

The retention and concentration of glycogen in Trichinella nativа in the winter-spring period

The metabolism of Trichinella spp. is primarily anoxybiotic in nature. Their main energy source is glycogen, which is stored in the stichocites at the muscular stage of the larval development. When subject to tow temperatures the Trichinella larvae consume glycogen and neutral fats to provide for basal metabolism until the energy supplies reach the critical level. The present study establishes the glycogen concentration as well the invasive activity of T. nativа when affected by low temperatures in natural conditions. The carcasses of infected laboratory rats were placed in containers beneath the snow cover, in the natural conditions of a game husbandry in Central Russia. The viability, invasive capacity and the glycogen level were monitored in the Trichinella larvae monthly. The invasive capacity of Trichinella larvae was established based on the presence of the larvae in the muscular tissue of laboratory mice after the peroral administration of the helminth larvae. On the 45 day of the experiment, the mice were euthanized by cervical dislocation, and if the Trichinella larvae could be discovered in the muscular tissue with the help of the trichinelloscopic compression method, the invasive capacity of the Trichinella larvae was viewed as positive. To establish the quantitative value of glycogen content in Trichinella larvae a modified method was used. In order to measure the glycogen level in the T. nativa larvae isolated by fermentation larvae were counted in one drop of the suspended sedimentation in the Migacheva-Kotelnikov chamber. To establish the quantitative value of glycogen content in Trichinella larvae a method based on the treatment of glycogen with iodine, optical density measurement with a refractometer MКMФ-02 was used. For the purpose of measuring the concentration of glycogen in Trichinella larvae in the suspended sedimentation a calibration curve was used. The studies showed that the viability indicator of the Trichinella larvae which had been preserved in natural conditions in the four months of the winter-spring period, in the muscular tissue of laboratory rats remained high (over 90 %). The glycogen concentration in one helminth larva was 0.041 μg in January, 0.033 μg in February, 0.015 μg in April. The invasive capability of the preserved Trichinella larvae was considerably reduced to 33.3 %. In the winter period, under temperatures below 0 °C, a decrease in the glycogen concentration in the Trichinella larvae was observed.

Epidemiology, diagnosis, treatment and control measures of trichinellosis in China: an overview

Trichinellosis is a worldwide zoonotic parasitic disease, which may infect humans and a wide range of animals, including carnivores, herbivores and even birds. Humans get infections through ingestion of raw or semi-cooked meat or meat products containing live Trichinella larvae. Currently, this zoonosis is predominantly prevalent in southwestern, northeastern and central parts of China, which poses a great threat to human health and socioeconomic development. In addition, the emergent public health hazards caused by trichinellosis outbreaks greatly threaten human health and social stability. This review describes the current status, diagnosis, treatment and control measures of trichinellosis in China, so as to provide insights into trichinellosis control in the country.

Trichinella spp. in wild boar (Sus scrofa) populations in Croatia during an eight-year study (2010–2017)

Wild animals represent a constant source of Trichinella spp. infections for domestic animals and humans. To date, four species of Trichinella have been isolated in wild boar populations in Europe: T. pseudospiralis, T. spiralis, T. britovi and T. nativa, in addition to several mixed infection types and one hybrid formation between T. britovi and T. spiralis. Meanwhile, insufficiently thermally processed wild boar meat has been reported to be a source of trichinellosis in humans in several European countries. In Croatia, there have been no reported or proven cases of trichinellosis caused by wild boar meat consumption. The aim of this study was to obtain data on the prevalence of Trichinella species present in Croatia and to anticipated the potential risk of infection for humans in specific Croatian regions based on information obtained over an eight-year surveillance period. A veterinary inspection of wild boar carcasses for Trichinella larvae in Croatia has been mandatory since 1989, and the artificial digestion method was introduced as a compulsory test for wild boar samples in 2008. Based on the official data submitted to the Ministry of Agriculture, Directorate of Veterinary Services, in the period 2010–2017, 303 of 183,184 (0.17%) wild boar meat samples tested positive for Trichinella spp. Infected wild boar were found in 18 of 21 counties. Of these positive samples, 85 were submitted by the authorised veterinary inspectors to the National Reference Laboratory for further examination. The intensity of infection in muscle samples was 0.04–152.66 (mean: 23,37) larvae per gram, and Trichinella species were identified as T. spiralis, T. britovi, T. pseudospiralis and T. spiralis + T. britovi. Genetic analysis of T. pseudospiralis isolates demonstrated their belonging to the Palaearctic population.

Human Outbreak of Trichinellosis Caused by Trichinella papuae Nematodes, Central Kampong Thom Province, Cambodia.

In September 2017, a severe trichinellosis outbreak occurred in Cambodia after persons consumed raw wild pig meat; 33 persons were infected and 8 died. We collected and analyzed the medical records for 25 patients. Clinical signs and symptoms included myalgia, facial or peripheral edema, asthenia, and fever. We observed increased levels of creatine phosphokinase and aspartate aminotransferase­, as well as eosinophilia. Histopathologic examination of muscle biopsy specimens showed nonencapsulated Trichinella larvae. A Trichinella excretory/secretory antigen ELISA identified Trichinella IgM and IgG. Biopsy samples were digested and larvae were isolated and counted. PCR for the 5S rDNA intergenic spacer region and a multiplex PCR, followed by sequencing identified the parasite as Trichinella papuae. This species was identified in Papua New Guinea during 1999 and in several outbreaks in humans in Thailand. Thus, we identified T. papuae nematodes in humans in Cambodia.

Serological assay for &lt;i&gt;Trichinella&lt;/i&gt; antibodies in slaughtered pigs and predisposing factors to trichinellosis in backyard piggeries in Kaduna Metropolis, Nigeria

Trichinellosis is a cosmopolitan zoonotic disease that affects a large array of mammals, birds and reptiles caused by the eating of raw or undercooked pork containing Trichinella larvae. In this study, 200 pigs slaughtered at abattoirs and slaughter slabs within Kaduna Metropolis were screened for antibodies to Trichinella excretory-secretory (E/S) antigen using Enzyme-linked Immunosorbent Assay (ELISA). An overall prevalence rate of 16% was established. Age of the pigs revealed an association with trichinellosis (p-value=0.001) with juvenile and adult pigs recording prevalence rates of 5% and 11% respectively. Sex of the animals showed no significant association with trichinellosis but the females had a higher prevalence of 9.5% compared to the 6.5% of the males who had a greater odds (O=1.083) compared to the females (O=0.950). The farm management practices: intensive (1%), semi-intensive (2.5%) and extensive (12.5%) recorded a significant relationship with trichinellosis (p-value=0.001). Sources of the pigs whether markets, backyard farms or inheritance was significantly associated with trichinellosis (p-value=0.00) with backyard farm having the highest prevalence of 7%. Poor rodents control program, presence of snakes around and within piggery, feeding of pigs with dead animals and leftovers, lack of knowledge of pork-borne diseases, allowing pigs to scavenge and interaction of the pigs with stray pigs were very important predisposing factors to trichinellosis in pig farms established from this research. The result of this work therefore, is ofpublic health importance because meat and meat products are considered very important sources of daily protein in-take in Kaduna Metropolis, Nigeria.&#x0D; Keywords: Antibodies; ELISA; Kaduna Metropolis; Nigeria; trichinella; trichinellosis; predisposing factors; farm management.

Species identification of Trichinella originated from various host and different geographical location by MALDI-TOF

The foodborne zoonotic nematode Trichinella spp. can cause human trichinellosis when raw or undercooked contaminated meat is ingested.To date, twelve Trichinella species/genotypes have been described. According to EU regulation any Trichinella larvae detected during mandatory routine examinations need to be identified at a species level by a competent laboratory. Currently, Trichinella species identification is performed using molecular biology tools such as multiplex PCR, PCR-sequencing or PCR-RFLP. These techniques require high level of skills for good interpretation of the results. Due to its rapidness and ease of use a matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) protocol was previously developed for the identification of Trichinella species.Using this method, spectra from different Trichinella species and strains were acquired allowing to generate new Main Spectra (MSP). Finally a new MSP database from Trichinella spp. Samples of different countries (France, Germany and Poland), including field samples, was generated. Comparing the different main spectra, Trichinella worms were identified at the species level and differences in the genetic diversities within the different species are discussed.In conclusion, using the previously described method on field samples is a reliable, rapid, easy-to-use and cheap tool for Trichinella species identification. The new Trichinella database could be incremented with new samples. It constitutes a tool, which could be used as an alternative method to replace the actual molecular methods for Trichinella species identification.

Trichinella spiralis – New method for sample preparation and objective detection of specific antigens using a chemiluminescence immunoassay

The parasitic roundworm Trichinella spiralis is most commonly transmitted to humans through consumption of raw or undercooked meat of infected pigs or game. To prevent human infection, slaughterhouses perform meat safety surveillance using the gold standard “Magnetic Stirrer Method”. We introduce a fast and objective method using automated detection of specific Trichinella spiralis antigens by a newly developed immunoassay based on chemiluminescence (ChLIA). Panel A comprised muscle tissue samples from non-infected pigs (n=37). Panel B comprised muscle tissue samples from non-infected pigs spiked with different amounts of Trichinella larvae without collagen capsules (n=56). Panel C contained muscle tissue samples from experimentally infected pigs including Trichinella larvae encapsulated in collagen (n=32). Each sample was shredded with PBS buffer in a knife mill, destroying Trichinella larvae. Following centrifugation, the supernatant (muscle tissue extract containing released excretory and secretory Trichinella spiralis antigens) was used for Trichinella-specific antigen detection by the new Trichinella ChLIA. The overall accuracy of the Trichinella ChLIA was 97.6 %. The specificity of the Trichinella ChLIA was 100 % (panel A). The sensitivity in samples from experimentally infected pigs was 100 % representing a detection limit of 0.01 larvae per gram. Cross-reactivity with parasites other than Trichinella spp. was not observed. This new meat inspection method for the detection of Trichinella spiralis antigens presents high specificity and high sensitivity, especially in truly infected samples. In contrast to the gold standard, this new approach to meat safety surveillance does not require longsome digestion or microscopy by trained personnel.

A Simple and Rapid Staining Technique for Sex Determination of Trichinella Larvae Parasites by Confocal Laser Scanning Microscopy

The roundworms of Trichinella genus are worldwide distributed and their prevalence in nature is high. Trichinella genus parasites are the causative agents of foodborne zoonosis trichinellosis. The main prevention and control of the infection are meat inspection by the magnetic stirrer method for the detection of Trichinella larvae in muscle samples. The treatment can be effective if the parasite is discovered early in the intestinal phase. Once the Trichinella larva has reached the muscle tissue, the parasite remains therein and there is no treatment for this life cycle stage. The Trichinella species is dioecious with separate male and female individuals. The developed staining technique that uses confocal laser scanning microscopy (CLSM) displays sufficient results for Trichinella larvae examination and this protocol is applicable to study the internal and external structures and for the sex determination of T. britovi and T. spiralis larvae samples. In the present study, a luminescent derivative was synthesized and used for staining of T. spiralis and T. britovi larvae samples for the examination by CLSM. Various fixatives, such as AFA, 70% ethanol, and Bouin's and Carnoy's solutions were tested for sample preparation. The synthesized luminescent compound demonstrates best visualization results for samples fixed in Bouin's fixative.

Trichinella spiralis muscle larvae release extracellular vesicles with immunomodulatory properties.

Extracellular vesicles (EVs) represent a newly discovered but universal communication tool between cells or organisms. However, few data exist on nematode EVs and none for Trichinella spiralis. Here, we aimed to investigate whether Tspiralis muscle larvae produce EVs, whether they carry immunomodulatory proteins and whether they have a role in immunomodulation as a component of excretory-secretory muscle larvae products (ES L1). EVs were enriched from conditioned medium of Tspiralis muscle larvae. Transmission electron microscopy images showed Tspiralis EVs to be 30-80nm in size, and Western blot confirmed the presence of two out of three glycoproteins with the immunodominant epitope characteristic for muscle larvae of the genus Trichinella. Using a peripheral blood mononuclear cell (PBMC) stimulation assay, it was shown that these EVs elevated production of IL10 and IL6. Tspiralis muscle larvae produce EVs. Those EVs carry immunomodulatory proteins and have the capacity independently to induce regulatory responses in the same way as the Tspiralis excretory-secretory muscle larvae products from which they were isolated.

Epidemiological Studies on Porcine Trichinellosis in Five States of North East India

This study was carried out to evaluate the epidemiological studies of trichinellosis in five states of North East India from Apr 2016 to Dec 2017. Overall, 865 different meat samples for detection of Trichinella larvae and 1580 sera samples for detection of anti-Trichinella antibody were collected. Intensity of infection with Trichinella larvae in meat was determined by HCL: Pepsin digestion procedure and anti-Trichinella IgG in serum were detected using excretory/secretory antigens, according to validated ELISA. No Trichinella larva was detected by HCL: Pepsin digestion method. However, four (0.25%) samples were seropositive for Trichinella IgG and four inconclusive results as per cut off value. The highest seroprevalence was observed in Meghalaya (0.41%) followed by Assam (0.27%) whereas no seropositive cases were recorded in Arunachal Pradesh, Mizoram and Tripura. Trichinellosis is common in North East, India. However, it is suspected in communities where more than 75% of the population relish pork. Finally, there is a need for more research to establish the facts of trichinellosis in this region. Thus, public awareness, food hygiene, monitoring, and surveillance programme are suggested to implement for prevention of trichinellosis in this region.

EFFECT OF POSITIVE TEMPERATURES ON THE GLYCOGEN CONTENT IN TRICHINELLA LARVAE

In the present study, the effect of positive temperatures on the content of glycogen, the main reserve polysaccharide of trichinella, which plays an important role in their metabolism, was studied. The concentration of glycogen, determined by the modi-fied method of E.O. Danchenko and A.A. Chirkina (2010), was 0.007 μg per 1 T. nativa larva on the third day of the experiment, which corresponded to the time period for their viability to zero.Trichinosis is a helminthic disease of humans and animals that belongs to the group of dangerous helminth toxic diseases. Due to the fact that trichinella mainly exhibit anoxybiotic metabolism, their main storage substance is glycogen, which they ac-cumulate in significant quantities at the muscular stage of development [3]. Consid-ering the fact that under the influence of positive temperatures, the newly isolated Trichinella larvae exhibit mobility, the mobilization of energy resources, primarily glycogen, to ensure the basal metabolism and motor activity continues until the en-ergy sources are reduced to a critical level. In this study, we established the concen-tration of glycogen in Trichinella nativa larvae in conjunction with the viability index under the influence of elevated temperatures, affecting the intensity of metabolism.

The Effect of Microwave Radiation on Metacercariae of Opisthorchis and Larvae of Trichinella

This article summarizes data on the influence of microwave radiation on the metacercariae of opisthorchids Opisthorchis felineus (Rivolta, 1884) and the larvae of three Trichinella species (genus Trichinella Railliet, 1895). The high efficiency of microwave radiation on the viability of larvae of these species is shown. Even short-term exposure leads to complete death of the larvae of the helminths in the muscle tissue. The mechanism of the effects of microwave irradiation on the larvae and the possibility of using household microwave ovens for preventing these parasitic diseases is discussed.

PECULIARITIES OF TRICHINELLA LARVAE DISTRIBUTION IN BADGERS’ MUSCLES THAT INHABIT IN AMUR REGION

Trichinellosis is a parasitic disease that affects animals and humans. Trichinella is a causative agent seen as a small round worm invisible to the eye. Trichinellosis affects pets and wild animals. Pigs, horses, dogs and synanthropic rats are seen to suffer from the disease more often among the domestic animals, and bears, wild boars, foxes, badgers and others – among the wild ones. . Human infection takes place when eating meat and meat products as raw dried homemade sausages and ham, kebabs, fried meat and other meat products contaminated with trichinell larvae. Infestation of wild animals is caused by predation or eating of dead animals. Pets are infected by eating slaughter products, food scraps and dead animals (rats). Trichinella are preserved in the animal muscles for some years. Badgers populations are seen as one of trichinosis reserves in Amur region. To determine specific features of trichinella larvae distribution in the lean tissue, the researchers explored the materials of 21 badgers from different areas of Amur region. The researchers used the heads or separate muscle groups for conducting the research. This is explained by remote location of many districts from the regional center. Trichinella larvae were detected by compressor trichinelloscopy and digestion in artificial gastric juice. The analysis showed that the number of trichinell larvae in the same muscle group does not depend on the side of the animal’s body, i.e. their number is almost identical on both the left and right sides. Invasion rate (IR) was defined as ratio of the number of infected animals to the total number of animals explored (in percentage). Invasion intensity (II) was determined by the number of trichinell larvae in 1 g of lean tissue (lye/g). The same method was used to investigate the distribution of trichinella larvae in 15 muscle groups of a badger. Invasion intensity in the infected animals was 14.3%. The largest number of trichinella larvae in a badger is concentrated in the head muscles, and there are no significant differences from the body part. The authors recommend to explore the badger carcasses and muscle sampling mainly from the head.