Fecal and molecular survey of Neospora caninum in farm and household dogs in Mashhad area, Khorasan province, Iran

Molecular detection and phylogenetic analysis of Neospora caninum in various hosts from Iran

Different N. caninum strains with distinct biological characteristics and pathogenicity have been introduced from various areas of the world. This study aimed to detect Neospora-infection in different hosts from Iran using the nested-Polymerase Chain Reaction (PCR) technique and to perform the phylogenetic analysis of N. caninum isolates using the Nc-5 gene. Different species of parasite hosts (cattle, dogs, rodents, cats, and birds) from the dairy farms with history of abortion with intensive breeding systems in Hamedan Province, Iran were included for sampling. The stillbirth fetuses of cattle, sheep, and goats were also collected from the slaughterhouse. The nested-PCR technique was used to identify the Neospora-DNA in the aborted fetal materials. The PCR products of the positive samples were sequenced and compared with other isolates in GenBank. Antibodies to N. caninum was found in 19.1% of dogs. Also, 11.4% of dogs were positive for Neospora-like oocysts using microscopy method. The molecular prevalence of N. caninum was 10.6% in dogs, 13.6% in cattle, 35.4% in the aborted fetuses of cows, 31.9% in rodents, 7.6% in pigeons, 1.9% in sparrows, 5.1% in cats, and 7% in the semen sample of bulls. A sampled coyote was positive while the stillbirth fetuses of sheep and goats were negative. The multiple sequence alignments indicated that 34 sequences of N. caninum bore a 94.9-99.3% similarity to each other. Hence, these sequences were classified into two major clusters (clusters A and B) and seven sub-groups (isolates 1-7). The sequence of coyote had a high similarity to the sequences derived from dogs and cows. Also, root diagram showed the isolates of current study and previous reported from Iran have a similar origin. This study provided a phylogenetic analysis of Neospora-infection in different hosts, and for the first time, explored Neospora-infection in coyotes from Iran. Different isolates were detected in the studied population in the region. Comparison of the sequences showed the farm dogs play an important role in the life cycle and distribution of the parasite; so the relationship of dogs with the herd and their access to aborted materials should be restricted. Also, regular control of rodents' population and culling of seropositive cows with a history of abortion is essential for cutting the chain of transmission.

Neospora caninum infection in Iran (2004-2020): A review

Knowledge on neosporosis and associated risk factors in different species of animals are so important for designing the control programs and reduce the economic losses globally. This literature review targeted for evaluating the infection rate of Neospora caninum in animals in Iran. Until April 2020, all of published documents in the main English and Persian-language databases were searched. A total number of 110 documents (English = 85 and Persian = 25) were extracted. Most of reports were sero-epidemiological studies using ELISA in Iranian cattle population. The range of Neospora infection was 3.8–76.2% in cattle, 0–54.6% in dogs, 0.9–9.9% in sheep, 6.2% in goats, 19.2–55.9% in buffaloes, 20–42.2% in horses, 52% in donkeys, 3.2–27% in camels, 14% and 19% in cats, and 0–20.4% in rodents. This rate in birds was 17.3% in chicken, 9.8% and 30.4% in pigeons, 2.8% and 3.7% in sparrows, and 9.9% in hooded crows. This is a comprehensive literature review on Neospora infection in Iran at the first time. The infection of N. caninum is widespread in Iran especially in dogs and cattle population. This review can provide baseline information for future research. Study on other hosts especially on wild and exotic animals is recommended for exact estimate of neosporosis in Iran. Investigations into molecular diagnosis and genotyping of N. caninum strains are also needed; this will be helpful for developing vaccines and finding the connection among wild and domestic cycles of disease. Education on the risk factors associated with N. caninum infection for is suggested farmers and rural public.

Molecular and Serological Study of Neospora caninum Infection among Dogs and Foxes in Sanandaj, Kurdistan Province, Iran

Neospora caninum, a protozoan parasite, causes abortions in cattle, as well as neurological disorders and reproductive problems in dogs. This study aimed to investigate the serological and the molecular prevalence of N.caninum among foxes and dogs using indirect fluorescent antibody test (IFAT) and nested-polymerase chain reaction (PCR). For this purpose, 288 and 95 both fecal and serum samples of dogs and foxes were collected, respectively, from around industrial and traditional dairy flocks in different parts of Sanandaj, Kurdistan Province, Iran, from 2013 to 2015. The sera were examined using IFAT, and fecal samples were microscopically assessed for detecting Neospora oocyst and by nested-PCR. The findings revealed that N.caninum seroprevalence were 4.86% and 4.21% in dogs and foxes, respectively. In addition, no Neospora oocysts were found microscopically and by PCR. Since this study is the first serological and molecular investigation of N.caninum among both dogs and foxes in Sanandaj, the findings of indicated that stray dogs is a main source of N.caninum infection in dairy farms in Sanandaj, Iran.

Risk of environmental exposure to small coccidia from wild canid feces in rural Ohio

OBJECTIVE To determine the extent of environmental exposure to heteroxenous coccidia from wild canid feces in southeastern Ohio. SAMPLE 285 presumed wild canid fecal samples collected across an ecological system in southeastern Ohio. PROCEDURES Morphological classification and molecular analysis were used to determine the canid genus for collected fecal samples. Microscopic and molecular analysis were used to detect coccidian oocysts and DNA. Several variables were analyzed for associations with coccidian DNA detection or prevalence. RESULTS Coccidian DNA was detected in 51 of 285 (17.9%) fecal samples. Of those positive samples, 1% (95% confidence interval, 0.4% to 3%) had positive results for Hammondia heydorni and none had positive results for Neospora caninum, for an estimated environmental N caninum prevalence of 0% (95% confidence interval, 0% to 7%)/1-km² hexagonal area evaluated. Morphological classification revealed that 78.9% (225/285) of fecal samples were from coyotes and 17.2% (49/285) were from foxes. No difference in proportions of coccidian DNA-positive fecal samples was identified among canid species. Environmental temperature and fecal freshness were associated with coccidian DNA detection. Land use type, relative canid density, and cattle density were not associated with the prevalence of coccidian DNA-positive samples. CONCLUSIONS AND CLINICAL RELEVANCE The low prevalence of coccidia shed in wild canid feces in this study, including the estimated 0% environmental prevalence of N caninum, suggested that the role of the oocyst environmental phase in coccidia transmission to ruminants is likely minor in rural southeastern Ohio.

Development of a loop-mediated isothermal amplification technique and comparison with quantitative real-time PCR for the rapid visual detection of canine neosporosis

Background

Dogs are the definitive hosts of Neospora caninum and play an important role in the transmission of the parasite. Despite the high sensitivity of existing molecular tools such as quantitative real-time PCR (qPCR), these techniques are not suitable for use in many countries because of equipment costs and difficulties in implementing them for field diagnostics. Therefore, we developed a simplified technique, loop-mediated isothermal amplification (LAMP), for the rapid visual detection of N. caninum.

Methods

LAMP specificity was evaluated using a panel containing DNA from a range of different organisms. Sensitivity was evaluated by preparing 10-fold serial dilutions of N. caninum tachyzoites and comparing the results with those obtained using qPCR. Assessment of the LAMP results was determined by recognition of a colour change after amplification. The usefulness of the LAMP assay in the field was tested on 396 blood and 115 faecal samples from dogs, and one placenta from a heifer collected in Lopburi, Nakhon Pathom, Sa Kaeo, and Ratchaburi provinces, Thailand.

Results

Specificity of the LAMP technique was shown by its inability to amplify DNA from non-target pathogens or healthy dogs. The detection limit was the equivalent of one genome for both LAMP and qPCR. LAMP and qPCR detected positive N. caninum infection in 15 of 396 (3.8%) blood samples; LAMP detected 9/115 (7.8%) positive faecal samples, while qPCR detected 5/115 (4.3%) positive faecal samples. The placental tissue was shown to be positive by both techniques. Agreement between LAMP and qPCR was perfect in blood samples (kappa value, 1.00) and substantial in faecal samples (kappa value, 0.697).

Conclusions

This is the first known LAMP assay developed for the amplification of N. caninum. The technique effectively and rapidly detected the parasite with high sensitivity and specificity and was cost-effective. This assay could be used in the field to confirm the diagnosis of canine or bovine neosporosis.

Electronic supplementary material

The online version of this article (doi:10.1186/s13071-017-2330-2) contains supplementary material, which is available to authorized users.

The detection and characterisation of Neospora /Hammondia-like oocysts from naturally infected dogs within the same urban region of Australia

This report describes the detection and molecular characterisation of Neospora/Hammondia-like oocysts from naturally infected dogs. Single faecal samples were collected from 160 individual greyhounds and multiple faecal samples were collected from 5 Labrador litters within a breeding kennel. Microscopy analysis detected Neospora/Hammondia like oocysts in 2 greyhounds and one litter of Labrador puppies. PCR protocols targeting the internal transcribed spacer region (ITS-1) and the large subunit (LSU) rDNA (D2/D3 domains) confirmed the presence of H. heydorni in both greyhounds and N. caninum in the Labrador litter. Dietary information obtained for all positive dogs indicate the source of infection was through regular exposure to a commercially obtained raw meat diet. These results report for the first time a natural infection with H. heydorni in dogs in Australia and also the first co-occurrence of N. caninum and H. heydorni in an Australian urban region.

Molecular identification of Neospora caninum from calf/foetal brain tissue and among oocysts recovered from faeces of naturally infected dogs in southern Ethiopia

This study sought to confirm and investigate further recently published information regarding the occurrence of Neospora caninum in cattle in Ethiopia and investigate infection in dogs, the canine definitive host, in this region. Faecal samples from 383 dogs in Hawassa, Ethiopia were examined by microscopy for Neospora-like oocysts, and positive samples then analysed by a molecular approach (DNA isolation, PCR and sequencing at the ITS1 gene). Brain tissue samples from four late term aborted foetuses, one congenitally defective calf (hind leg arthrogryposis) and placental tissue from cattle in the same area were also examined by the same molecular approach. All foetal, calf and placental tissue were associated with Neospora seropositive dams. A high prevalence of Neospora-like oocysts (11.5 μm±1.5 μm diameter) was observed in faecal samples from dogs (37 positive samples; 9.7% prevalence), and in 17 of these the identification was confirmed by PCR, giving a prevalence of confirmed infection of 4.4%. N. caninum DNA was also detected in all foetal and calf brain tissue samples. Sequencing revealed only minor differences among all PCR products, whether from oocysts or from brain tissue samples. These data provide molecular evidence of the presence of N. caninum infection in both dog and cattle in this region of Ethiopia. Moreover these findings highlight the role of dogs in maintaining and spreading the infection horizontally in the study area. The high frequency of N. caninum infection in household dogs as well as farm dogs is worthy of further investigation.