A survey of gastrointestinal helminth infestation in smallholder backyard pigs and the first molecular identification of the two zoonotic helminths Ascaris suum and Trichuris suis in Myanmar.

BACKGROUND: Parasitic infestations have a substantial economic impact on pig production. This study aimed to investigate the gastrointestinal (GI) helminths in pigs and to molecularly characterise two important nematodes, Ascaris and Trichuris species. MATERIALS AND METHODS: A total of 500 pig faecal samples were collected from small holder backyard pig farms in five townships within Nay Pyi Taw, Myanmar. Microscopic examination was conducted to estimate the prevalence of GI helminth infestation in the pigs. DNA extraction and PCR were performed on faecal samples that were morphologically positive for Ascaris and Trichuris eggs. Molecular analysis was then conducted to characterise A. suum and T. suis, the most common and zoonotic helminths. RESULTS: According to microscopic examination, 69.2% (346/500) were positive for GI helminth eggs. The GI helminth species observed were A. suum, Strongyle, Strongyloides spp., T. suis, Metastrongylus spp., Hyostrongylus spp., Fasciolopsis spp., Paragonimus spp., and Schistosoma spp., with occurrences of 34.8%, 29.6%, 21.4%, 20.0%, 4.0%, 1.6%, 1.0%, 1.0%, and 0.4%, respectively. Mixed infections of GI helminths were noted in 31.0% of the samples. Overall, sampled pigs excreted mostly low levels (< 100 EPG) or moderate levels (> 100-500 EPG) of GI helminth eggs. The highest mean EPG for each parasite species was noted in A. suum. The presence of A. suum and T. suis was confirmed molecularly. The sequences of the internal transcribed spacer 1 (ITS1) region of A. suum showed high similarity with previously reported sequences. Likewise, the sequences of T. suis exhibited high similarity with the sequences reported from humans and pigs. Age was noted as an associated factor (P < 0.05) for GI helminth infection status. CONCLUSIONS: In this report, A. suum and T. suis were molecularly identified for the first time in Myanmar. It is important to extend the information among the farmers to be aware of the necessity of preventing zoonotic parasites by practicing regular deworming, proper use of anthelmintics and maintaining hygienic conditions in their pig farms.

First detection and genetic characterization of canine bufavirus in domestic dogs, Thailand.

Canine bufavirus (CBuV) was reported in domestic dogs worldwide. We conducted a survey of canine bufavirus in domestic dogs in Thailand from September 2016 to October 2022. Rectal swab samples (n = 531) were collected from asymptomatic dogs and dogs with gastroenteritis signs. The samples were tested for CBuV using PCR with specific primers to the VP1/VP2 gene, and 9.42% (50/531) was CBuV positive. Our findings showed that CBuVs could be detected in both symptomatic and healthy dogs. The Thai CBuVs were found in dogs from different age groups, with a significant presence in those under 1 year (12.60%) and dogs aged 1-5 years (7.34%) (p < 0.05), suggesting a high prevalence of Thai CBuVs in dogs under 5 years of age. We performed complete genome sequencing (n = 15) and partial VP1/VP2 sequencing (n = 5) of Thai CBuVs. Genetic and phylogenetic analyses showed that whole genomes of Thai CBuVs were closely related to Chinese and Italian CBuVs, suggesting the possible origin of Thai CBuVs. The analysis of VP1 and VP2 genes in Thai CBuVs showed that 18 of them were placed in subgroup A, while only 2 belonged to subgroup B. This study is the first to report the detection and genetic characterization of CBuVs in domestic dogs in Thailand. Additionally, surveillance and genetic characterization of CBuVs in domestic animals should be further investigated on a larger scale to elucidate the dynamic, evolution, and distribution of CBuVs.

Morphological and molecular identification of trematode cercariae related with humans and animal health in freshwater snails from a lake and a dam in Myanmar.

Freshwater snails play an essential role in the transmission of trematode parasitic flatworms that can infect wild and domestic animals, as well as humans. This study aimed to investigate the rate of cercarial infections in freshwater snails collected from two study areas, Inlay Lake and Yezin Dam, in Myanmar. A total of 4,740 snail samples were collected from Inlay Lake (n = 3,837) and Yezin Dam (n = 903), and infection rate by cercarial emergence was examined. Cercarial DNA samples were analysed by PCR. Based on morphological characteristics, eleven snail species and eight cercarial types were identified. Snails of Melanoides tuberculata in the family Thiaridae were found as the most abundant, followed by Indoplanorbis exustus of the family Planorbidae, in both study areas. The infection rate by cercarial emergence in snails in Inlay Lake and Yezin Dam was 5.8% (224/3,837) and 48.6% (439/903), respectively. Echinostome cercariae showed the highest infection rate in both study areas. Phylogenetic analysis of cercarial internal transcribed spacer 2 (ITS2) sequences revealed that at least seven cercaria types belonged to five digenean trematode families, two of which were zoonotic trematodes in the families of Opisthorchiidae/Heterophyidae and Schistosomatidae. Furthermore, cercarial 28S ribosomal RNA gene analysis showed that the furcocercous cercariae in Yezin Dam were identified as Schistosoma spindale, a causative agent of ruminant schistosomiasis. This is the first report on zoonotic trematode cercariae in snails in Myanmar. The findings indicate that various snail species act as intermediate host for trematode species that infect aquatic animals, mammals and humans in the country.

The strong influence of management factors on coccidian infections in smallholder pig farms and the first molecular identification of Cystoisospora suis in Myanmar.

A cross-sectional study was conducted to investigate coccidian infection and associated factors in smallholder pigs, and to identify Cystoisospora oocysts by PCR. A total of 500 pig faecal samples from 330 smallholder farms were collected in Nay Pyi Taw, Myanmar. The faecal flotation method was used to identify Eimeria and Cystoisospora species, and oocyst counts per gram (OPG) of faeces were recorded. Oocysts were differentiated after sporulation. Oocyst DNA was subjected to ITS1-targeted Cystoisospora-specific PCR. The overall coccidian oocyst detection rate by microscopic was 89.0% (445/500). Among the studied samples, 74.0% (370/500) and 70.6% (353/500), were found to be positive with Eimeria spp. and Cystoisospora suis oocysts, respectively. The sequences of C. suis detected were 100% identical to those of C. suis reported from Japan, and had 99.5% resemblance to sequences from Australia and China. Weaner pigs showed the significantly highest (p < 0.05) OPG when compared to other age groups. The highest intensity of coccidian infection (p < 0.05) was found in pigs fed local feed, pigs raised on earthen floors and pigs under poor hygienic conditions. Factors such as age, breed, feed type, and housing floors were found to be significantly associated with coccidian infection (p < 0.05). Age, as well as management factors including floor type, feed type, and hygiene practices on the farm, had a strong influence on the occurrence of coccidian infection in pigs. This is the first study in Myanmar on coccidian infection in pigs and molecular detection of C. suis.

TITLE: Forte influence des facteurs de gestion sur les infections à coccidies dans les petites exploitations porcines et première identification moléculaire de Cystoisospora suis au Myanmar. ABSTRACT: Une étude transversale a été menée pour étudier l'infection coccidienne et les facteurs associés chez les porcs dans des petites exploitations, et pour identifier les oocystes de Cystoisospora par PCR. Au total, 500 échantillons de matières fécales de porcs provenant de 330 petites exploitations agricoles ont été collectés dans la région de Nay Pyi Taw, au Myanmar. La méthode de flottation fécale a été utilisée pour identifier les espèces d'Eimeria et de Cystoisospora, et le nombre d'oocystes par gramme (OPG) de matières fécales a été déterminé. Les oocystes ont été différenciés après sporulation. L'ADN des oocystes a été soumis à une PCR spécifique à Cystoisospora, ciblée sur ITS1. Le taux global de détection d'oocystes de coccidies au microscope était de 89,0 % (445/500). Parmi les échantillons étudiés, respectivement 74,0 % (370/500) et 70,6 % (353/500) ont été trouvés positifs pour Eimeria spp. et les oocystes de Cystoisospora suis. Les séquences de C. suis détectées étaient identiques à 100 % à celles de C. suis signalées au Japon, et avaient 99,5 % de ressemblance avec des séquences d'Australie et de Chine. Les porcs sevrés ont montré un OPG significativement plus élevé (p < 0,05) par rapport aux autres groupes d'âge. L'intensité la plus élevée de l'infection coccidienne (p < 0,05) a été observée chez les porcs nourris avec des aliments locaux, les porcs élevés sur des sols en terre battue et les porcs dans de mauvaises conditions d'hygiène. Des facteurs tels que l'âge, la race, le type d'alimentation et les étages se sont avérés être significativement (p < 0,05) associés à l'infection coccidienne. L'âge, ainsi que les facteurs de gestion, notamment le type de sol, le type d'alimentation et les pratiques d'hygiène dans la ferme, ont eu une forte influence sur la survenue d'une infection coccidienne chez les porcs. Il s'agit de la première étude au Myanmar sur l'infection coccidienne chez le porc et la détection moléculaire de C. suis.

Occurrence of gastrointestinal helminths and the first molecular detection of Ancylostoma ceylanicum, Trichuris trichiura, and Trichuris vulpis in dogs in Myanmar.

Dogs may serve as hosts for a variety of zoonotic or potentially zoonotic helminths, including Ancylostoma ceylanicum and Trichuris species. Cross-sectional study design was used to collect 210 faecal samples of dogs from Nay Pyi Taw area, Myanmar. According to microscopic examination, 180 samples (85.7%) were positive for eight species of gastrointestinal helminths. Among them, positive rates of Ancylostoma species and Trichuris species eggs were observed as 79.0% (166/210) and 11.9% (15/210), respectively. Molecular identification of A. ceylanicum and Trichuris species was confirmed by COX1 gene- and SSU rRNA gene-targeted PCR. Partial sequences of COX1 and SSU rRNA showed 100% identity with A. ceylanicum, Trichuris trichiura, and Trichuris vulpis deposited in GenBank.

The first seroepidemiological study on Toxoplasma gondii in backyard pigs in Myanmar.

A cross-sectional study of Toxoplasma gondii infection in pigs was carried out in backyard farms in three townships, within Nay Pyi Taw area from June 2014 to August 2014. Blood samples were randomly collected from 256 pigs in 129 farms. Using commercial Latex Agglutination Test kits, specific antibodies to T. gondii were analyzed. Based on LAT results, among 256 serum samples examined, 47 samples (18.4%) were found positive to T. gondii. The numbers of samples showing specific antibody titres from 47 positive pig sera were 20 at 1:64, 2 samples at 1:128, 9 samples at 1:256, 3 samples at 1:512 and 13 samples at 1:1024. Among the hypothesized risk factors, roaming of cats around the farm was found associated to T. gondii seropositivity in pigs (OR = 3.13; 95% CI = 1.33-7.34). This study provides information on seroepidemiology study of T. gondii in backyard pigs for the first time in Myanmar. This information will be useful in developing strategies for the control of T. gondii infection in pigs.

Microscopic and molecular detection of Eimeria maxima and Eimeria praecox naturally infected in free-range village chickens of Myanmar.

PURPOSE: In Myanmar, village chicken production is an important source of both income and food for rural households. The present study is aimed to conduct microscopic detection and molecular identification of Eimeria species in free-range village chickens in Myanmar. METHODS: Faecal samples were taken from a total of 122 apparently healthy village chickens from three rural regions in Myanmar. The faecal samples were subjected to flotation method using a saturated sugar solution. Oocysts of Eimeria sp. were isolated by saturated sugar solution onto coverslips and identified to species at 400 × by light microscopy. Molecular identification was conducted for Eimeria oocysts collected from faecal samples using 18S rRNA and internal transcribed spacer-1 (ITS-1). RESULTS: Eimeria oocysts were found in 41 samples (33.6%) by flotation method. Oocysts morphologically identified as E. maxima and E. praecox, were detected in 33 (27.0%) and 15 (12.3%) samples, respectively. Mixed infection of these two species was found in 7 (5.7%). Partial sequences of the 18S rRNA gene amplified from morphologically identified oocysts of E. maxima and E. praecox, revealed 99.9% and 100%, identities with the sequences of each species deposited in GenBank, respectively. Species-specific PCR of the ITS-1 region was also confirmed the presence of these two Eimeria species. CONCLUSION: The results demonstrated the presence of E. maxima and E. praecox in free-range village chickens in Myanmar.

Molecular Prevalence and Identification of Ehrlichia canis and Anaplasma platys from Dogs in Nay Pyi Taw Area, Myanmar.

Ticks are vectors of different types of viruses, protozoans, and other microorganisms, which include Gram-negative prokaryotes of the genera Rickettsiales, Ehrlichia, Anaplasma, and Borrelia. Canine monocytic ehrlichiosis caused by Ehrlichia canis and canine cyclic thrombocytopenia caused by Anaplasma platys are of veterinary importance worldwide. In Myanmar, there is limited information concerning tick-borne pathogens, Ehrlichia and Anaplasma spp., as well as genetic characterization of these species. We performed nested PCR for the gltA gene of the genus Ehrlichia spp. and the 16S rRNA gene of the genus Anaplasma spp. with blood samples from 400 apparently healthy dogs in Nay Pyi Taw area. These amplicon sequences were compared with other sequences from GenBank. Among the 400 blood samples from dogs, 3 (0.75%) were positive for E. canis and 1 (0.25%) was positive for A. platys. The partial sequences of the E. canis gltA and A. platys 16SrRNA genes obtained were highly similar to E. canis and A. platys isolated from different other countries.

Occurrence of Gastrointestinal Parasites in Small Ruminants in the Central Part of Myanmar.

Gastrointestinal parasite infection in small ruminants remains one of the major economic losses caused by reduced productivity. A total of 380 faecal samples were taken from 280 sheeps in Magway and Pwintbyu Townships and 100 goats in Natmauk Township, Myanmar. Faecal flotation and sedimentation methods were carried out to detect the presence of parasitic infections. Faecal egg and oocyst counts were carried out using the McMaster technique. The overall occurrence of gastrointestinal parasites in small ruminants was 98.4% (374/380). The occurrence of gastrointestinal parasites in sheep (99.3%) was higher than that in goats (96%). The highest occurrence was found in Eimeria spp. (96%), followed by Trichostrongyle (77.1%), Trichuris spp. (35%), and Moniezia expansa (14%). The mixed infection rate was 84.8% (317/374), while a single infection was 15.2% (57/374). The mean eggs per gram (EPG) and oocysts per gram (OPG) of faeces were ranged from 50 to 600 and 50 to 29,800, respectively. Among the 4 nucleotide sequences isolated, one sequence was 94.10-94.47% similarity with Trichostrongylus colubriformis, reported from Laos, and three sequences showed 96.64-99.46% identity with Haemonchus contortus from Laos, China, India, and Mongolia. As gastrointestinal parasite infection in small ruminants was relatively high in the study area, the development of appropriate treatment and control measures should be provided to reduce production losses.

Morphological and molecular identification of cyathostomine gastrointestinal nematodes of Murshidia and Quilonia species from Asian elephants in Myanmar.

Gastrointestinal nematode parasites have long been recognized in Asian elephants. The most common parasites belong to the subfamily Cyathostominae of the family Strongylidae, which are small to medium-sized with a cylindrical buccal capsule surrounded by coronal leaflets. Diagnostic keys of such parasites are provided from old illustrations in the form of line drawings. However, there very few photomicrographs and no genetic information of these parasites exist. In the present study we obtained adult worm specimens from faeces of Asian elephants after anthelmintic treatment in two elephant camps in Myanmar. Here, we provided photomicrographs for five cyathostomine parasites, Murshidia falcifera, Murshidia indica, Murshidia neveulemairei, Quilonia renniei, and Quilonia travancra almost 100 years after their original drawings. In addition, we determined the mitochondrial cytochrome c oxidase subunit I (COI) gene sequences of these species. Phylogenetic analysis of the COI genes of Murshidia and Quilonia species from Asian and African elephants revealed parasite speciation in each elephant host. The present study also indicated that several Murshidia and Quilonia species were widely distributed in Asian elephants in Myanmar, providing new insight into control strategies and evolution of cyathostomine gastrointestinal parasites in elephants.