Genetic identification of Entamoeba polecki subtype 3 from pigs in Japan and characterisation of its pathogenic role in ulcerative colitis

Prevalence of gastrointestinal parasitism in pigs of Tripura, India

Pigs breeds are an important livestock species mostly reared by economically lower incomesection of people in India. Within North-Eastern (NE) states, pig husbandry is very much popular hence maintain the livelihood of the rural native population. Gastrointentinal (GI) parasitic infectionisone of the major constraint in profitable pig production in this area. In the present study, the GI parasitism was investigated in 388 pigs in the three districts of Tripura, NE State of India. The examination of faecal samples revealed 61.65% overall prevalence of parasitic infestation, precisely6 GI parasitic species; including 4 nematodes and 2 protozoa, while 46.91% were the mixed infections.Metastrongylus spp. (17.53%), Strongyloids spp. (19.33%),Trichuris spp. (15.98%), Coccidia spp. (12.37%), and Balantidium coli (10.82%), were detected, however, Ascaris spp. was the most prevalentrecording 32.47%. The epidemiological factors including: age, sex, season, breed, area and farming system wise when considered as markers of study showed the highest prevalence of GI parasites in grower(6-12 months) stage, female, monsoon season, non-descript breeds, Khowai district and free range farming system, recorded 71.52%, 67.27%, 65.78%, 65.71%, 64.57%, and 69.44%, respectively. Overall, our study provides a baseline data for further investigation and formulation of strategies for control of GI parasitism in pigs in Tripura.

A parasitological survey and the molecular detection of Entamoeba species in pigs of East Java, Indonesia

Background and Aim: In several countries, two Entamoeba porcine species, Entamoeba suis and Entamoeba polecki (subtype 1 and 3), have been detected using molecular methods and identified pathogenicity associated with enteritis. However, globally, Entamoeba infection prevalence in pigs is extremely limited. This study aimed to coprologically and genetically examine pig parasites to estimate prevalence of Entamoeba in three pig farms in East Java, Indonesia. Materials and Methods: Hundred porcine fecal samples (Landrace) were collected from three East Javan farms in well-known swine industry regions. Fecal samples were examined under microscope after sugar-flotation centrifugation, and molecular species and subtype identification were performed using polymerase chain reaction (PCR) and primer pairs targeting small-subunit ribosomal RNA. Results: Microscopy examinations identified parasites in 89/100 fecal samples; Entamoeba spp. cysts were the most frequent in these samples. Polymerase chain reaction showed that 58 samples were comprised of mixed Entamoeba suis and Entamoeba polecki, 22 E. suis alone, and nine E. polecki alone infections. Epolec F6–Epolec R6 primers successfully amplified E. polecki ST1–4 subtypes, while Epolecki 1–Epolecki 2 amplified only the E. polecki ST1 subtype. Entamoeba polecki ST1-specific primers successfully detected the ST1 subtype in 19/67 E. polecki positive samples. Conclusion: Entamoeba spp. prevalence in Indonesian pigs was previously shown to be high. On coprological examination of East Javan pigs, we detected high Entamoeba spp. levels, in which we genetically identified as E. suis (80.0%), E. polecki (67.0%), and E. polecki ST1 (19%). Keywords: East Java, Entamoeba, Indonesia, pig, polymerase chain reaction, small-subunit ribosomal rRNA.

Molecular Characterization of Entamoeba spp. in Pigs with Diarrhea in Southern China

Entamoeba spp. is a common zoonotic intestinal protozoan that can parasitize most vertebrates, including humans and pigs, causing severe intestinal diseases and posing a serious threat to public health. However, the available data on Entamoeba spp. infection in pigs are relatively limited in China. To characterize the infection of Entamoeba spp. within pigs in southern China, 1254 fecal samples of diarrheic pigs were collected from 37 intensive pig farms in Hunan, Jiangxi and Fujian provinces and the infection of Entamoeba spp. was investigated based on the small subunit rRNA (SSU rRNA) gene. The overall infection rate of Entamoeba spp. was 58.4% (732/1254), including 38.4% (118/307) in suckling piglets, 51.2% (153/299) in weaned piglets, 57.9% (55/95) in fattening pigs and 73.4% (406/553) in sows, respectively. Moreover, age and the sampling cities in Jiangxi and Fujian provinces were found to be the key factors influencing the infection of Entamoeba spp. (p < 0.05). Two subtypes (ST1 and ST3) with a zoonotic potential of Entamoeba polecki and Entamoeba suis were detected in all age groups of pigs and all sampling areas, with the predominant species and predominant subtype being E. polecki (91.3%, 668/732) and E. polecki ST1 (573/668), respectively, and E. polecki ST1 + E. polecki ST3 (78.6%, 239/304) being the most frequently detected form of mixed infection. Severe Entamoeba spp. infection and zoonotic subtypes were found in this study, exposing a large public health problem in the study area, and strategies need to be implemented to eliminate the risk in the future.

A Comparative Study of Cattle and Sheep Amoebiasis in Selected Regions of Baghdad City

This study was performed to microscopically detect the prevalence of amoebiasis in cattle and sheep fecal samples. One hundred fecal samples were collected from cattle and sheep from 3 completely different area in Baghdad city (Al-Tarmiyah, Al-Fudhaliyah, AbuGhraib). Our data recorded a total amoebiasis infection rate of 54% in cattle and 50% in sheep, without any significant differences between them. Males showed higher infection rates than females in cattle and sheep (62.5%) and (57.14) respectively. The difference between age groups with significant difference (P<0.01) were obtained in ages <1 year (72.7%) and (68.75%) in cattle and sheep respectively. This study has demonstrated the widespread of Entamoeba parasite in cattle and sheep in Baghdad city.

Gastrointestinal parasites of indigenous pigs (Sus domesticus) in south-central Nepal

BACKGROUND

Intestinal parasites have a significant impact on productivity of pigs. Additionally, presence of zoonotic parasites in pig faeces used as fertilizer and ingestion of raw or undercooked pork products originated from parasite-infested pigs pose a risk to human health.

OBJECTIVES

The aim of the study was to estimate the prevalence and diversity of gastrointestinal (GI) parasites in indigenous pigs (Sus domesticus) maintained under traditional rearing system in Nepal.

METHODS

Fresh faecal samples (n = 100) were collected from the pigs of varying age and sex maintained in 18 small-scale farms in south-central Nepal. Samples were processed using various standard methods and examined for parasite eggs, cysts or oocysts.

RESULTS

Prevalence of GI parasites in indigenous pigs was 91%, comprising of 14 different genera of protozoans and helminths. Male pigs generally had a higher (97.5%) prevalence of GI parasites than females (87%). While 90% of the suckling and weaner piglets were positive for the GI parasites, all growers and 85% the adult pigs were infected with the parasites. Entamoeba spp. were the primary protozoans in all age groups. Strongyloides sp. was more prevalent helminths in suckling and weaner piglets, whereas Ascarid spp. were higher in both growers and adults. Triplet infection was higher (33.3%) in suckling and weaner piglets, while quadruplet and pentuplet infections were higher (p < .05) among growers (46.7%) and adults (30%), respectively.

CONCLUSIONS

The indigenous pigs harbour a higher prevalence and greater diversity of GI parasites. GI parasitism varies by sex and age of the pigs.

Occurrence and genetic identifications of porcine Entamoeba, E. suis and E. polecki, at Tangerang in West Java, Indonesia

Entamoeba suis and E. polecki subtype (ST) 1 and ST3 recently have been inferred to be virulent in pigs. However, because relevant molecular epidemiological surveys have been limited, the prevalences of these species remain unknown and their pathogenicities are still controversial. We surveyed 196 fecal samples of pigs (118 of adults, 78 of piglets) at Tangerang in West Java, Indonesia, in 2017, employing PCR using porcine Entamoeba-specific primers. E. suis was the more frequently detected species, observed in 81.1% of samples, while E. polecki ST1 and ST3 were detected in 18.4% and 17.3% of samples, respectively; mixed infections (harboring 2-3 species or subtypes of Entamoeba) were confirmed in 29.3% of positive samples. Statistically significant differences in the positive rates were not seen between adult pigs and piglets, except for those of E. polecki ST3. The prevalences of Eimeria spp. and/or Cystoisospora suis (79.1%), strongyles (55.6%), and Strongyloides spp. (6.1%) were also observed morphologically in the samples. Further chronological or seasonal investigations of pigs and humans in these high-prevalence areas are needed to assess the virulence of the Entamoeba parasites, including the effects on pig productivity, and to evaluate the zoonotic impacts of these organisms.

Inclusion body hepatitis caused by Aviadenovirus in a tropical screech owl (Megascops choliba)

In 2016, tropical screech owl (Megascops choliba) (Tso) chicks were suddenly found dead in a Japanese breeding facility. We autopsied a 9-day-old Tso and discovered white spots scattered on the liver surface. Multifocal necrosis was diffused, and macrophages had infiltrated the necrotic hepatic lesions. Hepatocytes contained numerous intranuclear inclusion bodies. Immunohistochemical staining detected Adenovirus antigen only in the liver. Next, PCR and sequencing (LC536616) identified Tso Adenovirus (TsoAd). Basic Local Alignment Search Tool (BLAST) and phylogenic analyzes suggested TsoAd is an owl Aviadenovirus. Our study contributes to an improved understanding of infectious disease among captive raptors.

Copro-molecular study of Entamoeba infection among the indigenous community in Malaysia: A first report on the species-specific prevalence of Entamoeba in dogs

BACKGROUND

Entamoeba is a free-living protozoan parasitic species that infect a variety of hosts. In humans, Entamoeba histolytica is the causative agent of amoebiasis. Entamoeba species has also been reported in dogs. However, little is known about the molecular epidemiology and the specific species of this parasite in dogs globally, including Malaysia. As dogs are important companion animals for the indigenous community, and close contact with dogs is part of the natural living conditions for this community, this study aims to determine the prevalence and molecular epidemiology of Entamoeba species in human and dogs in Malaysia.

METHOD

The presence of Entamoeba species was examined in 504 fresh fecal samples, collected randomly from 411 humans and 93 dogs using microscopy and polymerase chain reaction (PCR) amplifying 16 s ribosomal RNA (rRNA). Data was analyzed using appropriate statistical analysis.

RESULTS

The microscopy data showed an overall occurrence of Entamoeba species of 26.3% (108/411) and 36.6% (34/93) in humans and dogs respectively. In humans, the most common species was a single infection of E. dispar (26.5%; 13/49), followed by E. histolytica and E. moshkovskii, (20.4% for each species respectively). Double infection of E. dispar + E. moshkovskii was detected at 10.2%, followed by E. dispar + E. histolytica (8.2%) and E. moshkovskii and E. histolytica (6.1%). 8.2% of the samples had triple infection with all three species. In animals, E. moshkovskii (46.7%) was the most common species detected, followed by E. histolytica, and E. dispar, at 20.0% and 13.3% respectively. Double infection with E. moshkovskii + E. histolytica and a triple infection were found in 2 samples (13.3%) and 1 (6.7%) sample respectively. Risk factor analysis showed that members of the community who used untreated water were more prone to be infected with Entamoeba.

CONCLUSION

This study provides information on the species-specific occurrence of Entamoeba infection, the potential risk factors and their zoonotic potential to humans. This is the first report to describe the molecular occurrence of Entamoeba species in dogs in Malaysia. The presence of pathogenic Entamoeba species implies that dogs could be a reservoir or mechanical host for human amoebiasis. Further studies need to be conducted to better understand the transmission dynamics and public health significance of Entamoeba species in human and animal hosts.

A SURVEY FOR ZOONOTIC AND OTHER GASTROINTESTINAL PARASITES IN PIG IN BALI PROVINCE, INDONESIA

Pigs have potentially to transmit zoonotic gastrointestinal parasite disease both caused by protozoa and worm. The aim of this study was to identify gastrointestinal parasites that were potentially zoonotic in pigs in the province of Bali. A total of 100 fresh feces samples was collected from several pig farms in Bali, from Badung and Tabanan districts, each consisted of 50 samples. Pig feces samples were examined for the presence of eggs worms, cysts and oocysts for protozoa based on the morphology and size. Identification for protozoa and worms used native, sedimentation and sucrose flotation methods. Parameters measured were sex, feed and cage management. The result showed that the characteristic parameters for pigs in both district were generally female. Cage management for raising pigs mostly used group cage. Feed that provided in both district mostly used bran and concentrate. All of 100 pig feces samples that examined positive for parasites. There were 8 types of gastrointestinal parasites that have been identified. Four types of protozoa found were Entamoeba sp. (99%), Balantidium sp. (79%), Eimeria sp. (78%), Blastocystis sp. (69%) and four types of worms were Ascaris sp. (20%), Trichuris sp. (20%), Strongyloides sp. (19%), and Oesophagostomum sp. (8%). All pigs were infected with two or more parasites. The prevalence of parasitic gastrointestinal infections was different for each district, six genera (Entamoeba sp., Balantidium sp., Blastocystis sp., Eimeria sp., Oesophagostomum sp. and Trichuris sp.)  were higher found in Tabanan district and the two genera (Ascaris sp. and Strongyloides sp.) were higher in Badung district. Oesophagostomum sp. was only found to infect pigs in Tabanan district. The conclusion is gastrointestinal parasites that found in pigs at Badung and Tabanan district Bali Province mostly have zoonotic potential.

Swine multifocal ulcerative colitis and crypt abscesses associated with Entamoeba polecki subtype 3 and Salmonella Typhimurium

Piglets aged approximately 50 days exhibited diarrhea and wasting. Multiple white foci were detected in the colon of a dead piglet; histopathological findings revealed multifocal ulcers and crypt abscesses with Entamoeba trophozoites and gram-negative bacilli in the piglet. These pathogens were identified as Entamoeba polecki subtype 3 and Salmonella enterica serovar Typhimurium, respectively. Numerous E. polecki subtype 3 trophozoites were located on the edge of the ulcerative and necrotic lesions in the lamina propria. Crypt abscesses were associated with S. Typhimurium. These results suggest that E. polecki subtype 3 caused multifocal ulcerative colitis accompanied by crypt abscesses with S. Typhimurium in the piglet. This study is the first report of colitis with E. polecki subtype 3 and S. Typhimurium coinfection.

Prevalence and Genetic Identification of Three Entamoeba Species in Pigs in Southeastern China

Parasitic Entamoeba spp. can infect many classes of vertebrates including humans and pigs. Entamoeba suis and zoonotic Entamoeba polecki have been identified in pigs, and swine are implicated as potential reservoirs for Entamoeba histolytica. However, the prevalence of Entamoeba spp. in pigs in southeastern China has not been reported. In this study, 668 fecal samples collected from 6 different regions in Fujian Province, southeastern China, were analyzed to identify three Entamoeba species by nested PCR and sequencing analysis. The overall prevalence of Entamoeba spp. was 55.4% (370/668; 95% CI 51.6% to 59.2%), and the infection rate of E. polecki ST1 was the highest (302/668; 45.2%, 95% CI 41.4% to 49.0%), followed by E. polecki ST3 (228/668; 34.1%, 95% CI 30.5% to 37.7%) and E. suis (87/668; 13.0%, 95% CI 10.5% to 15.6%). E. histolytica was not detected in any samples. Moreover, the coinfection rate of E. polecki ST1 and ST3 was 25.1% (168/668; 95% CI 21.9% to 28.4%), the coinfection rate of E. polecki ST1 and E. suis was 3.7% (25/668; 95% CI 2.3% to 5.2%), the coinfection rate of E. polecki ST3 and E. suis was 0.3% (2/668), and the coinfection rate of E. polecki ST1, E. polecki ST3, and E. suis was 4.0% (27/668; 95% CI 2.5% to 5.5%). A representative sequence (MK347346) was identical to the sequence of E. suis (DQ286372). Two subtype-specific sequences (MK357717 and MK347347) were almost identical to the sequences of E. polecki ST1 (FR686383) and ST3 (AJ566411), respectively. This is the first study to survey the occurrence and to conduct molecular identification of three Entamoeba species in southeastern China. This is the first report regarding mixed infections with E. suis, E. polecki ST1, and E. polecki ST3 in China. More research studies are needed to better understand the transmission and zoonotic potential of Entamoeba spp.

Metagenomics for broad and improved parasite detection: a proof-of-concept study using swine faecal samples

Efficient and reliable identification of emerging pathogens is crucial for the design and implementation of timely and proportionate control strategies. This is difficult if the pathogen is so far unknown or only distantly related with known pathogens. Diagnostic metagenomics - an undirected, broad and sensitive method for the efficient identification of pathogens - was frequently used for virus and bacteria detection, but seldom applied to parasite identification. Here, metagenomics datasets prepared from swine faeces using an unbiased sample processing approach with RNA serving as starting material were re-analysed with respect to parasite detection. The taxonomic identification tool RIEMS, used for initial detection, provided basic hints on potential pathogens contained in the datasets. The suspected parasites/intestinal protists (Blastocystis, Entamoeba, Iodamoeba, Neobalantidium, Tetratrichomonas) were verified using subsequently applied reference mapping analyses on the base of rRNA sequences. Nearly full-length gene sequences could be extracted from the RNA-derived datasets. In the case of Blastocystis, subtyping was possible with subtype (ST)15 discovered for the first known time in swine faeces. Using RIEMS, some of the suspected candidates turned out to be false-positives caused by the poor status of sequences in publicly available databases. Altogether, 11 different species/STs of parasites/intestinal protists were detected in 34 out of 41 datasets extracted from metagenomics data. The approach operates without any primer bias that typically hampers the analysis of amplicon-based approaches, and allows the detection and taxonomic classification including subtyping of protist and metazoan endobionts (parasites, commensals or mutualists) based on an abundant biomarker, the 18S rRNA. The generic nature of the approach also allows evaluation of interdependencies that induce mutualistic or pathogenic effects that are often not clear for many intestinal protists and perhaps other parasites. Thus, metagenomics has the potential for generic pathogen identification beyond the characterisation of viruses and bacteria when starting from RNA instead of DNA.

Coinfection with Entamoeba polecki and Brachyspira hyodysenteriae in a pig with severe diarrhea

Enteric disease in pigs is usually of multifactorial etiology, including infectious and non-infectious factors. In many cases of endemic diarrhea in weaner-to-finisher pigs, the combination of 2 or more microorganisms leads to aggravation of intestinal lesions and, consequently, clinical signs. We autopsied a 4-mo-old fattening pig with diarrhea and diagnosed severe fibrinonecrotizing typhlocolitis. Numerous spiral-shaped bacteria and amoeba-like PAS-positive protozoa were observed in the cecal and colonic mucosa and submucosa. Brachyspira hyodysenteriae was detected by PCR from colonic content. By in situ hybridization, large numbers of Entamoeba polecki were found within the lamina propria and submucosa; moderate numbers of Blastocystis sp. and scattered trichomonads were present in intestinal content. In addition, Entamoeba polecki, Balantidium spp., Blastocystis sp., and Trichomonas sp. were also detected by PCR.

First report on the occurance of intestinal Entamoeba spp. In pigs In China

Three Entamoeba spp. including E. suis, zoonotic E. polecki, and E. histolytica, have been described in pigs to date. However, little is known about the molecular epidemiology of these neglected parasites in pigs globally. In this study we surveyed the occurrence and molecular epidemiology of porcine Entamoeba spp. in pigs in eastern China and evaluated their zoonotic potential. Five hundred fresh fecal samples, collected from seven pig farms in Anhui province, eastern China,were examined for the presence of E. histolytica, E. suis, and E. polecki ST1 and ST3 infections by a combination of nested PCR targeting the small subunit ribosomal DNA gene and subsequent sequencing.The overall occurrence of Entamoeba spp. was 45.8% (229/500). Infection with E. polecki ST1 (38.2%; 191/500) was the most common, followed by E. polecki ST3 (10.0%; 50/500), and E. suis (0.8%; 4/500). No E. histolytica infection was detected. Double infections with E. polecki ST1 and E. suis, and with E. polecki ST1 and ST3 were found in two (0.4%) and 14 (2.8%) samples, respectively. No age predisposition to infection with Entamoeba spp. was observed. PCR and subsequent sequencing confirmed the validity and feasibility of the nested PCR method used in this study in identifying species/subtypes of porcine Entamoeba spp.This is the first report to describe the occurrence and molecular epidemiology of Entamoeba species in pigs in China. The presence of two zoonotic E. polecki subtypes implies that pigs can be reservoirs for human E. polecki infections. More studiess are needed to better understand the transmission and public health significance of porcine Entamoeba spp.

Evaluation of a PCR Method for Detection of Entamoeba polecki, with an Overview of Its Molecular Epidemiology

Entamoebapolecki is a parasite of human and nonhuman primates, other mammals, and birds. Due to overlapping morphological features, cysts of E. polecki may be confused with those of other Entamoeba species commonly found in human fecal samples, including immature cysts of Entamoeba histolytica Although the presence of E. polecki in human Entamoeba-positive stool samples may be rare, its prevalence is likely underestimated due to such confusion. Here, we give examples of diagnostic approaches applied so far and summarize data on the molecular epidemiology of E. polecki, including host specificity and phylogeography. Moreover, we evaluate a novel diagnostic conventional PCR developed for the screening of fecal samples for E. polecki The assay was highly sensitive and specific when used on genomic DNA extracted directly from stool and Swedish wastewater samples. The PCR enabled the identification of all four subtypes (ST1 to ST4) of E. polecki by PCR product sequencing. Most (23/28) subtyped E. polecki-positive samples detected in patients in Sweden between 2002 and 2015 reflected colonization by ST4 and were seen in travelers/foreigners. Two and three human cases of ST2 and ST3, respectively, were also detected. Subtypes 1, 2, and 3 were detected in 3/21 wastewater samples, suggesting local endemicity of these E. polecki subtypes; interestingly, ST4 was not detected in wastewater. In conclusion, the current PCR assay enables simple and cost-effective screening of fecal and wastewater samples for E. polecki Human cases of E. polecki appear to involve primarily ST4, while E. polecki detected in wastewater may be primarily of animal origin.

Prevalence, molecular epidemiology, and zoonotic potential of Entamoeba spp. in nonhuman primates in China

Amebiasis is a major public-health concern. It has a global distribution, and is listed as the third leading parasitic cause of human mortality. To survey the prevalence and assess the potential zoonotic transmission of Entamoeba spp. in nonhuman primates (NHPs) in China, 2688 fresh fecal specimens were collected from NHPs reared in farms or zoos/parks or free ranging in 13 districts. The overall prevalence of Entamoeba spp. infection determined with microscopy analysis was 39.4% (1059/2688). Higher infection rates were detected in the free ranging group (41.1%, 169/411) and in animals <1year old (58.7%, 556/947). Gene fragments were successfully amplified 463 (87.2%) out of the 531 selected specimens (approximately half of the total microscopy-positive specimens). Polymerase chain reaction (PCR) amplification identified 386 (83.4%) Entamoeba dispar and 287 (62.0%) E. coli infections, and among these, 210 (45.4%) were mixed infections. And that the E. dispar and E. coli had also been detected in humans. In phylogenetic analysis, the E. dispar and E. coli sequences clustered with reference E. dispar and E. coli, respectively. In conclusion, nonhuman primates infected with Entamoeba species, with high prevalence and zoonotic potential, should be considered when evaluating the maintenance of Entamoeba spp. and its transmission between animal reservoirs and humans.

Development of molecular diagnostic protocols for detecting three types of Entamoeba from diarrheal and asymptomatic pigs and environmental moist soils

Entamoeba suis and Entamoeba polecki subtypes (ST) 1 and 3 have recently been implicated in disease outbreaks in pigs. However, the distributions of these parasites in Japan and the potential sources of infection on farms still remain unclear. Here, we examined a farm of fattening/growing pigs with abnormal feces in Kagoshima Prefecture, Japan, and found the presence of parasites in the farm environment. Examination of intestinal tissues from pigs presenting with ulcerative colitis revealed a large number of trophozoites that had invaded the lesions. We identified single and mixed infections of E. suis and E. polecki ST1 and ST3 in paraffin sections or fecal samples from affected pigs. Two subtypes of Entamoeba were identified using four primer sets by PCR and sequencing. The parasites were detected in moist soil samples obtained around the drinking water source or puddles, implicating transmission of cysts via contaminated soils. Additionally, we found evidence of Entamoeba spp. and coinfections in surveyed pigs without any diarrhea at two neighboring farms. Our results establish methods for successfully identification of parasites, including cases in which multiple infections are present.

First report of mixed Entamoeba polecki (ST 1) and E. suis infection in piglets shedding abnormalfeces by histopathological and molecular surveys

Of the three species of Entamoeba found in swine, namely E. histolytica, E. polecki and E. suis, E. histolytica can also infect humans, producing colitis or abscesses of liver and leading to death. However, the pathogenicity of other species of Entamoeba has not been fully characterized. Here, we conducted histopathology and molecular surveys on a pig farm where piglets had blackish feces or muddy diarrhea. Histopathological examination of two piglets showed necrosis of the mucous surface at the ileum, cecum, or colon, infiltration of neutrophils, and formation of ulcers. Based on morphological characteristics, E. polecki and E. suis trophozoites were mainly detected at lamina propria and surface of the lesion, respectively, and Lawsonia intracellularis, a bacterial pathogen, was also detected. Molecular analysis using the small subunit ribosomal RNA gene on other piglets and a sow revealed infection with both E. polecki and E. suis. These findings corroborate our previous reports that the two Entamoeba spp. are pathogenic in pigs as aggravations of symptoms with L. intracellularis. This is the first report about mixed infection with E. polecki and E. suis.