Serological survey of Toxoplasma gondii infection in the one-humped camels (Camelus dromedarius) in the south of Iran.

BACKGROUND: Toxoplasmosis, an important zoonotic disease, is caused by Toxoplasma gondii. Camels are one of several host species for T. gondii parasites and play an important role in the transmission of T. gondii to humans. OBJECTIVES: The present study aimed to describe the seroprevalence of T. gondii in dromedary camels (Camelus dromedarius) from three provinces (Fars, Bushehr and Hormozgan), southern Iran first for this host. METHODS: A total of 180 serum samples were analysed for the presence of anti-Toxoplasma IgG antibodies using the enzyme-linked immune-sorbent assay. RESULTS: Our results showed an overall seroprevalence of T. gondii in 15% of animals. Antibodies to T. gondii were found in sera of 27 of 180 dromedary camels from Fars, Bushehr and Hormozgan provinces, southern Iran. Age or the gender of the camel did not significantly affect the seroprevalence (p > 0.05). There was no significant association between herd-level seroprevalence of T. gondii infection and abortion history, province location residence, history of animal keeping and history of contact with other animals (p > 0.05). CONCLUSIONS: The results of this study showed the presence of T. gondii antibodies among camels in Southern Iran, which could be a public health concern. According to the prevalence of T. gondii infection in camel, the implementation of control measures to reduce infection in both definitive and intermediate hosts is needed.

Development and evaluation of an indirect ELISA for detection of Teladorsagia circumcincta infection in sheep.

BACKGROUND: The gastrointestinal helminth, Teladorsagia circumcincta, is one of the major health risks and production-limiting diseases in small ruminant populations, particularly in temperate regions. With the increasing importance of disease management and recruited anthelmintic resistant types, accurate approaches are needed for the diagnosis of the infection in the host. Due to uncertain results using faecal examinations, the ELISA method was indicated for the detection of nematode antigenic materials. Despite some promising results, problems were described in terms of test specificity and cross-reactions. Therefore, this study aimed to evaluate the IgG response to worm somatic and excretory/secretory (ES) products using western blot analysis and an indirect ELISA for the detection of T. circumcincta infection in sheep. RESULTS: Based on the immuno-reactivity analysis, immunogenic fractions with molecular weights (MWs) of approximately 60, 75 and 100 kDa were detected in somatic content and two antigens of about 63 and 75 kDa in ES material. Accordingly, a specific product at 75 kDa had the strongest reaction and appeared as the most common antigenic protein. In ELISA, all the sera from the infected sheep revealed the OD rates above the calculated cut-off value with about two-fold greater average. Negative control samples were also specifically recognized with the mean OD rate of about 1/3 of the estimated cut-off value. The cross-reaction test, using rabbit anti-T. circumcincta IgG, did not show reactivity with the ES antigens of other prevalent nematodes including Haemonchus contortus, Protostrongylus rufescens and Marshallagia marshalli. In contrast, a strong positive reaction was observed with the somatic antigens of M. marshalli. CONCLUSIONS: The results of this study indicated that the indirect ELISA method using the ES content enables distinguishing the T. circumcincta infected sheep with high specificity. Those antigenic ES peptides with 63 and particularly 75 kDa MWs should be further investigated due to the potential for serological diagnostic methods and immunoprotective targets in the host.

Detection and characterization of the Isospora lunaris infection from different finch hosts in southern Iran.

This study was conducted to investigate the Isosporoid protozoan infections in finch types. Fecal samples were collected from marketed domestic Java sparrows (Lonchura oryzivora), colored and white Zebra finch (Taeniopygia guttata), and European goldfinch (Carduelis carduelis) in southern Iran. The coccidial oocysts were recovered and investigated according to the morphological features and the ribosomal gene markers. Additionally, a challenge infection was conducted with 5 × 104 and 5 × 103 sporulated oocysts in four java sparrows to estimate the clinical manifestations. Based on the morphology, the oocysts of Isospora lunaris were identified in all sampled bird types; however, the molecular method revealed the isolates had considerable similarities with some of Isospora and systemic Isospora-like organisms named as Atoxoplasma. Phylogenetic data also constructed an Atoxoplasma/Isospora clade with high sequence identities. High dose of the challenge with the parasite led to severe depression and sudden death, but it did not coincide with remarkable lesions and parasitic invasion in visceral organs. Contrary to molecular results, this feature is consistent with the common Isospora infections in passerines and differs from those described for Atoxoplasma species. Because of the prevalence, possibility of transmission, and clinical consequences, preventive measures are necessary to avoid outbreaks of isosporoid infections among finch type birds.