Seroprevalence of Toxoplasma gondii in Sheep,Cattle and Horses in Urmia North-West of Iran

Background

Toxoplasma gondii is a zoonotic protozoan parasite found worldwide and responsible for major economic losses in most classes of livestock. This study was aimed to determine the prevalence of T. gondii infection in sheep, cattle and horses in Urmia, north-west of Iran, using MAT.

Methods

Blood samples of 276 livestock and 26 horses were collected from July 2009 till April 2010. The data were analyzed by the Chi-square, Fisher''s Exact and Cochran''s and Mantel-Haenszel Tests. The level of significance was set at P<0.05.

Results

Thirty-three (21.1%) sheep, 2 (1.6%) cattle and 3 (11.5%) horses were seropositive to T. gondii. Analysis showed that sheep were 15 times more likely to be seropositive comparing to cattle also 2 times more likely to be seropositive than horses.

Conclusion

This study showed seroprevalence of equine T. gondii infection with a considerable rate in sheep in Urmia, northwest of Iran. More comprehensive studies on livestock toxoplasmosis are required for further analysis of the parasite reservoir for human infection.     

Infection of hard ticks in the Caspian Sea littoral of Iran with Lyme borreliosis and relapsing fever borreliae

The Caspian Sea littoral of Iran is home to various hard tick species, including Ixodes ricinus, the notorious vector of Lyme borreliosis (LB) in Eurasia. Here, in this area, we examined I. ricinus and other hard ticks, along with common rodents and small mammals for LB and relapsing fever (RF) borreliae infection. Ticks were collected from various mammalian hosts, including sheep, goats, cattle, camels, horses, dogs, donkeys, rodents, and hedgehogs. Rodents and small mammals were live-captured from different habitats. A real-time PCR for 16S rRNA sequence revealed borrelial DNA in 71 out of 501 (≈14 %) specimens belonging to I. ricinus and Rhipicephalus ticks. None of the rodents and small mammals showed borrelial infection in the viscera. PCR amplification and sequencing of a 600-bp sequence of the flaB identified Borrelia bavariensis, Borrelia garinii, Borrelia afzelii, and Borrelia valaisiana, and the RF Borrelia, B. miyamotoi in I. ricinus ticks. The RF-like Borrelia in Rhipicephalus ticks shared the highest identity (98.97 %) with an isolate infecting Haemaphysalis megaspinosa ticks in Japan. Our phylogeny and BLAST analysis suggest the range extension of the European I. ricinus-associated borreliae into the north of Iran.     

Molecular typing of Giardia duodenalis in cattle,sheep and goats in an arid area of central Iran

Giardia duodenalis is one of the most common intestinal parasites in humans as well as livestock and wildlife. It is of both public and veterinary health importance in developing nations. A molecular survey of Giardia duodenalis assemblages in ruminants from Yazd Province, Iran was conducted on 484 animal faecal samples collected per rectum from slaughtered ruminants including 192 cattle, 192 sheep and 100 goats from June to November 2017. Species-specific and assemblage-specific PCRs for assemblages A, B and E at the triose phosphate isomerase (tpi) gene were performed, and samples positive for Giardia were confirmed by sequencing. In total, 25 (5.16%) of examined faecal samples including eight cattle (4.2%), twelve sheep (6.2%) and five goats (5%) were infected with G. duodenalis. Assemblage-specific PCR detected G. duodenalis assemblage E in seven faecal samples (six in sheep and one in a goat). Assemblages A and B were not detected. This study provides the first insight into Giardia infection in slaughtered livestock in Iran. Although the prevalence of infection with Giardia in this hot-arid area of Iran was low, educating people about direct contact with livestock such as farmers and abattoirs workers about this zoonotic infection is important.     

Genetic diversity analysis of Blastocystis subtypes and their distribution among the domestic animals and pigeons in northwest of Iran

Blastocystis is a unicellular, anaerobic, eukaryotic protist, a common parasite found in the intestinal tracts of animals and humans. During the last few years, the host fecal DNA analysis by nucleic acid-based method has led to significant advances in Blastocystis diagnostics and enabled subtypes (STs). The zoonotic transmission of Blastocystis to humans is not well understood, therefore the present study was conducted to identify Blastocystis subtypes in Iran from different animal hosts from northwest of Iran. A total of 427 fresh fecal specimens were collected from cattle, sheep, poultry and pigeon (40,150,132,105 respectively). To detect the Blastocystis sp., each fecal specimen was examined microscopically. Total DNA from the samples that were positive for Blastocystis sp. was isolated, and the barcoding region of the small subunit of ribosomal rRNA (18S rRNA) was amplified and sequenced. Subsequently, sequence analyses, genetic diversity indices and evolutionary relationships of Blastocystis subtype populations were carried out. In total, 14.98% of the analyzed samples were positive for Blastocystis sp. and the subtypes detected were ST3,7,10 and 14. Among these, the ST10 was the main subtype that was found only in the cattle, sheep and poultry and the zoonotic subtype ST3 was present only from cattle. Our study shows the presence of Blastocystis subtypes in the sheep in north west of Iran and also demonstrated that the genetic approaches are crucial to understand the host specify of subtypes and the mode of infection. The study suggests that the genetic approaches will help us to understand the host specificity of subtypes and their role in infection if they are obtained from human and animals from the same geographical locations. Therefore, it is important to study the zoonotic aspects of this parasite with large number of samples from different groups of animals and from different geographical locations.     

Detection and Identification of Toxoplasma gondii Type One Infection in Sheep Aborted Fetuses in Qazvin Province of Iran

Background

The aim of this study was to apply the nested-PCR and bioassay methods in detection and genotyping of Toxoplasma gondii infection in provided sheep aborted fetus samples from Qazvin Province of Iran.

Methods

Eighteen sheep aborted fetal samples were studied by nested-PCR-RFLP, histopathological observation and microbiological assay. Bioassay in mice was carried out by inoculating the brain samples intraperitoneally.

Results

The results demonstrated the frequency of 66% infected sheep aborted fetal samples with T. gondii type one. Although we could not isolate any parasite from inoculated mice even after three passages, but it was confirmed histopathologically formation of cyst like bodies in prepared mice brain sections.

Conclusion

The results of the performed nested-PCR and formation of brain cyst in inoculated mice exhibited that T. gondii type one infection might be considered as one of the major causative agents for abortion in ewes.     

Genetic Identification of Orientobilharzia turkestanicum from Sheep Isolates in Iran

Background:

Adult worms of Orientobilharzia turkestanicum live in the portal veins, or intestinal veins of cattle, sheep, goat and many other mammals causing orientobilharziasis. Orientobilharziasis causes significant economic losses to livestock industry of Iran. However, there is limited information about genotypes of O. turkestanicum in Iran.

Methods:

In this study, 30 isolates of O. turkestanicum obtained from sheep were characterized by sequencing mitochondrial cytochrome c oxidase subunit 1 (cox1) and nicotinamide adenine dinucleotide dehydrogenase subunit 1 (nad1) gene. The mitochondrial cox1 and nad1 DNA were amplified by polymerase chain reaction (PCR) and then sequenced and compared with O. turkestanicum and that of other members of the Schistosomatidae available in Gen-Bank^™.

Results:

Phylogenetic relationships between them were re-constructed using the maximum parsimony method. Phylogenetic analyses done in present study placed O. turkestanicum within the Schistosoma genus, and indicates that O. turkestanicum was phylogenetically closer to the African schistosome group than to the Asian schistosome group.

Conclusion:

Comparison of nad1 and cox1 sequences of O. turkestanicum obtained in this study with corresponding sequences available in Genbank^™ revealed some sequence variations and provided evidence for presence of microvarients in Iran.     

Molecular Detection and Identification of Theileria Species by PCR-RFLP Method in Sheep from Ahvaz,Southern Iran

Background

The present study was carried out to investigate the accurate status of ovine Theileria infection in sheep from Ahvaz and surrounding region, a tropical area southwest Iran.

Methods

A PCR-RFLP method based on 18S ribosomal RNA gene was designed which could detect and differentiate Theileria and Babesia spp. and also differentiate main Theileria species in sheep at the same time. 119 sheep blood samples were collected from Ahvaz and surroundings.

Results

Microscopic examination of blood smears revealed 69.7% (83/119) infection with Theileria spp. Of the total samples subjected to PCR, 89% (106/119) were found to be positive, all of which were identified as Theileria by RFLP analysis using enzyme Hind II. In enzymatic digestion of PCR products by Vsp I, 91.5% (97/106) of Theileria positive samples were identified as T. ovis while mixed Theileria infections were found in 9 samples. The samples with mixed infections were analyzed with an additional nested PCR-RFLP method, by HpaII enzyme digestion. 3 samples with T. lestoquardi infection, 1 sample with T. ovis and T. annulata, 1 sample with T. lestoquardi and T. annulata, and 4 samples with T. ovis, T. lestoquardi and T. annulata mixed infections were detected.

Conclusion

Ovine theileriosis caused by T. ovis is highly prevalent in southwest Iran while T. lestoquardi and T. annulata infection can be detected in a lesser propor-tion of sheep in this region. The new PCR-RFLP method that was designed in this study, can serve as a beneficial diagnostic tool, especially in T. ovis prevalent re-gions.     

Seroprevalence of severe fever with thrombocytopenia syndrome virus in medium-sized wild mammals in Miyazaki,Japan

Severe fever with thrombocytopenia syndrome (SFTS) is a fatal emerging tick-borne zoonotic disease caused by the SFTS virus (SFTSV). SFTSV infection in humans and companion animals is a matter of concern in endemic areas. Various wild animals are involved in the transmission cycle of SFTSV with vector ticks. Because the home range of medium-sized wild mammals commonly overlaps with humans’ living spheres, this study aimed to reveal the endemicity of SFTSV in such mammals. This study investigated the prevalence of antibodies against SFTSV and viral RNA in medium-sized wild mammals in Miyazaki Prefecture, Japan where human cases have been most frequently reported in Japan and performed a phylogenetic analysis to compare the detected SFTSV with those previously reported. Forty-three of 63 (68%) Japanese badgers (Meles anakuma) and 12 of 53 (23%) Japanese raccoon dogs (Nyctereutes procyonoides viverrinus) had antibodies against SFTSV. Japanese marten (n = 1), weasels (n = 4), and Japanese red fox (n = 1) were negative. Two of 63 (3%) badgers tested positive for SFTSV RNA, whereas the other species were negative. Phylogenetic analysis of the partial nucleotide sequence of SFTSV revealed that viral RNA detected from badgers exhibited 99.8% to 100% similarity to SFTSV, as previously reported in humans, cat, and ticks in the study area. This study demonstrated high seropositivity of antibodies in medium-sized wild mammals and suggested that SFTSV could be shared among these mammals, humans, and companion animals in endemic areas.     

Transovarial Transmission of Babesia ovis by Rhipicephalus sanguineus and Hyalomma marginatum

Background

Rhipicephalus sanguineus and Hyalomma marginatum are the most common species in sheep herds in Northeast of Iran. There is preliminary evidence that these species may be the vectors of Babesia ovis in Iran. We carried out two experiments in Mashhad area, Khorasan Razavi Province to determine whether B. ovis could be transovarially transmitted by R. sanguineus and H. marginatum.

Methods

In experiment 1, adults of laboratory reared H. marginatum and R.sanguineus were infected with B. ovis isolated from naturally infected sheep in Mashhad area by feeding the ticks on the sheep inoculated intravenously by infected blood samples. The inoculated sheep showed clinical signs with parasitaemia while the adult ticks were engorging on them. The engorged females were collected and kept at 28°C and 85% relative humidity in incubator. Then, larval, nymphal and adult stages derived from engorged females were used to infest the clean sheep. In experiment 2, two splenectomized sheep were infested only with the same adult ticks of two species.

Results

Examination of smears and PCR of blood samples to detect of B. ovis in infested sheep in two experiments were negative.

Conclusion

It seems that R. sanguineus and H. marginatum can not transovarially transmit B. ovis in sheep.     

Cryptosporidium Spp. Infection in Human and Domestic Animals

Background

Cryptosporidium spp. is a coccidian parasite infected humans and animals. Prevalence rate of Cryptosporidium spp. infection associated with is some parameters such as sampling, age, season, country and contact to domestic animals. This study aimed to determine Cryptosporidium spp. Infection in humans and some animals in rural areas of Shushtar district from Khuzestan Province, south- west of Iran.

Methods

In this study, Stool specimens were randomly collected from 45 cattle, 8 buffalos, 35 calves, 22 turkeys, 3 sheep, 2 geese as well as 62 humans in different seasons selected from rural areas of Shushtar district located in Khuzestan in the south- west of Iran from August 2009 to April 2011. The collected stool samples were examined by modified Ziehl-Neelsen staining method.

Results

Altogether, 68/115 (59.1%) domestic animals and 9/62 (14.5%) of humans were showed Cryptosporidium spp. infection in the study areas.

Conclusion

In this study we found the high frequency of Cryptosporidium spp. infection in the studied areas.     

Incidence and Genetic Characterization of Gongylonema pulchrum in Cattle Slaughtered in Mazandaran Province,Northern Iran

Background

The gullet worm, Gongylonema pulchrum Molin, 1857, is a thread-like spirurid nematode found in a variety of mammals worldwide. Its incidences in Iranian cattle of different breed or age have not been reported. The aims of the present study are to disclose the infection status of G. pulchrum in cattle slaughtered in northern region of Iran.

Methods

Full-length esophagi of cattle of 97 native dairy breed and 41 Holstein-Friesian breed were collected at four local abattoirs in Mazandaran Province, northern Iran, from March 2006 to August 2007, and were examined parasitologically. Eight overlapping segments of the small- and large-subunits of rDNA were amplified by PCR, and the obtained nucleotide sequences were characterized.

Results

The incidences of G. pulchrum in female and male native dairy breed were 38.9% and 24.0%, respectively, whereas those in female and male Holstein-Friesian breed were 4.2% and 0%, respectively. The first internal transcribed spacer (ITS1) region of G. pulchrum rDNA showed an intra-individual variation in the sequence and length, and the variation was ascribed to some unstable repeats of "A" or "CA".

Conclusion

Distinct incidences of G. pulchrum infection in native dairy breed and Holstein-Friesian breed might be ascribed to different animal husbandry manners for each breed in Iran; the former breed grazes freely in the pasture, but the latter breed is usually held in a pen. The rDNA sequence of Iranian G. pulchrum, obtained for the first time by us, might facilitate a reliable species identification of the parasite with a wide spectrum of morphological variations.     

Schistosoma haematobium infection in the opossum (Didelphis marsupialis): involvement of the urogenital system

Investigations of experimental schistosomiasis haematobia have suffered for want of satisfactory mammals in which schistosome infections would establish host—parasite situations more or less comparable with those seen in man. As a consequence, mammals representing different major groups have been exposed to infection by Schistosoma haematobium (Iran strain) to determine their potential use as models for more detailed investigations. In preliminary studies, 8 American opossums (Didelphis marsupialis) were exposed to 1000 or 2000 cercariae. Macroscopic involvement of the urogenital tract was noted in 3 animals, one of which had a 1-cm fibrous plaque in the bladder. In another animal, multiple transitional cell papillomas were present in the bladder and in one ureter.     

Enzyme-linked immunosorbent assays for the detection of antibody to Crimean-Congo haemorrhagic fever virus in the sera of livestock and wild vertebrates.

IgM antibody response to Crimean-Congo haemorrhagic fever (CCHF) virus was monitored in experimentally infected sheep and cattle by an IgM capture enzyme-linked immunoassay (ELISA). Specific binding of antigen was detected by a rabbit anti-CCHF horseradish peroxidase conjugate or a sandwich technique with hyperimmune mouse anti-CCHF ascitic fluid and commercially available anti-mouse immunoglobulin peroxidase conjugate. The persistence of IgM antibody activity was found to be of shorter duration than in humans, and this may be a function of the relative lack of susceptibility of these animals to infection with CCHF virus. IgG antibody responses in the sheep could be monitored by sandwich ELISA using commercially available anti-sheep immunoglobulin peroxidase conjugates. Total antibody activity in the sera of experimentally infected sheep, cattle and small mammals could be monitored in a competitive ELISA (CELISA) using rabbit anti-CCHF peroxidase conjugate. The CELISA was applied to the sera of 960 wild vertebrates from a nature reserve in South Africa, and the prevalence of antibody was found to be greatest in large mammals such as rhinoceros, giraffe and buffalo, which are known to be the preferred hosts of the adult tick (Hyalomma) vectors of the virus.     

Identification and Genetic Variation of Fasciola Species from Tabriz,North- Western Iran

Background

Fascioliasis is considered as the most important helminthic infection of cattle and sheep. Traditional approaches using morphological and biologic characters cannot cause a certainty in the accurate and precise identification and intra-specific differences of Fasciola spp. In this study, we identified Fasciola species using ITS-1 marker and described genetic variation of each species of the parasite in isolates from Tabriz slaughterhouse in West Azerbaijan Province, north- western Iran.

Methods

Overall, 100 samples (50 from sheep and 50 from cattle) morphologically detected as Fasciola worms were studied for identification of Fasciola species by PCR-RFLP method and intra-species variation of the parasite using RAPD-PCR technique.

Results

A region of approximately 460bp in all samples was successfully amplified. There were no identifiable variations among the size of PCR products. Two and three fragments in samples correspond to F. hepatica and F. gigantica was seen, respectively, through PCR-RFLP method. No difference was seen in digestion pattern according to host (sheep or cattle). Different types of each species of the parasite was observed using RAPD-PCR technique.

Conclusion

We could have an estimate of frequency of F. hepatica and F. gigantic and different genotypes of the parasite in isolates from one locality in north- western of Iran. By extension of such studies in future to other animal hosts (buffalo and goat) and including more regions to sampling, the reliability of the results and their application for control programs in zoonotic diseases will be increased.     

Molecular Survey of Toxoplasma gondii in Sheep,Cattle and Meat Products in Chaharmahal va Bakhtiari Province,Southwest of Iran

Background

Toxoplasmosis is a worldwide spread disease. The present study examined the prevalence of Toxoplasma gondii infection among animals of edible meat (cattle and sheep) in Chaharmahal va Bakhtiari Province (Southwest of Iran) in 2012. Furthermore, we attempted for the first time to identify this parasite from the meat products in the province.

Methods

The tongue, brain, femur muscle and liver of 50 sheep and 70 cattle as well as 50 samples of meat products were selected and collected to perform molecular survey using Nested-PCR method.

Results

Of the studied sheep, 38% were infected. The infection rate in the age groups under 1 year, 1-2 years, and more than 2 years was 25%, 35.29% and 52.94%, respectively. The infection rate in femur muscle, brain, liver and tongue was 28%, 32%, 30% and 16%, respectively. Of the studied cattle, 8.57% were infected. The infection rate in the age groups 1-2 years, 2-4 years, and more than 4 years was 3.7%, 9.09% and 14.28%, respectively. Sheep was infected 6 times more than cattle (OR = 6.53 CI = 2.374-18.005).The infection rate among samples of meat products was 12% (6 samples out of 50 samples).

Conclusion

Due to the high rate of this parasitic infection among the slaughtered animals as well as meat products in this region, the use of infected material can be one of the main risk factors of transmission of the parasite to humans.     

Molecular Detection and Identification of Zoonotic Microsporidia Spore in Fecal Samples of Some Animals with Close-Contact to Human

Background: Microsporidia species are obligatory intracellular agents that can infect all major animal groups including mammals, birds, fishes and insects. Whereas worldwide human infection reports are increasing, the cognition of sources of infection particularly zoonotic transmission could be helpful. We aimed to detect zoonotic microsporidia spore in fecal samples from some animals with close – contact to human. Methods: Overall, 142 fecal samples were collected from animals with closed-contact to human, during 2012-2013. Trichrome – blue staining were performed and DNA was then extracted from samples, identified positive, microscopically. Nested PCR was also carried out with primers targeting SSU rRNA gene and PCR products were sequenced. Results: From 142 stool samples, microsporidia spores have been observed microscopically in 15 (10.56%) samples. En. cuniculi was found in the faces of 3 (15%) small white mice and 1 (10%) laboratory rabbits(totally 2.81%). Moreover, E. bieneusi was detected in 3 (10%) samples of sheep, 2 (5.12%) cattle, 1 (10%) rabbit, 3 (11.53%) cats and 2 (11.76%) ownership dogs (totally 7.74%). Phylogenetic analysis showed interesting data. This is the first study in Iran, which identified E. bieneusi and En. Cuniculi in fecal samples of laboratory animals with close – contact to human as well as domesticated animal and analyzed them in phylogenetic tree. Conclusion: E. bieneusi is the most prevalent microsporidia species in animals. Our results can also alert us about potentially zoonotic transmission of microsporidiosis.Key Words: Laboratory animals, Enterocytozoon bieneusi, Encephalitozoon cuniculi, Zoonotic transmission     

Visceral leishmaniasis in Iran: Review of the Epidemiological and Clinical Features

Visceral leishmaniasis (VL) is a life-threatening vector-borne parasitic disease is distributed in some parts of the new world and old world. The disease is endemic in different parts of Iran. This review article has been focused on major topics of epidemiological aspects and clinical features of VL in Iran for the period of 2002 through 2012. For the detection of VL in humans as well as animal reservoir hosts, anti-Leishmania antibodies were detected using direct agglutination test (DAT) as a validated serological test. Parasitological examinations were performed on suspected VL patients as well as canines and rodents. Different molecular methods were used for identification of species and genotype/ or strain of Leishmania spp. isolated from infected humans, animal reservoir hosts and vectors. Altogether, 1698 out of 36081 (4.7%) human serum samples collected from 5 distinct geographical zones showed anti-Leishmania antibodies at titers ≥ 1:3200 using DAT. The majority of VL cases in the endemic areas were found among children up to 12 years old. Almost 75% of DAT-positive cases (≥1:3200) in endemic areas showed clinical signs and symptoms. Predominant signs and symptoms in 217 hospitalized patients with DAT positive (≥1:3200) results included paleness (99.5%), fever (96.9%), splenomegaly (91.5%), hepatomegaly (53.6%) and lymphadenopathy (21.1%). Integrated VL surveillance system in primary care using DAT, could decrease mortality and morbidity of the disease in the VL endemic areas of the northwestern Iran. Out of 7204 serum samples collected from domestic dogs in various geographical locations of Iran, 879 (12.2%) were DAT sero-positive at titers ≥ 1:320. L. infantum as the principal causative agent of the disease was isolated from infected humans, domestic and wild canines and rodents. The principal animal reservoir hosts of the infection are domestic and wild canines. Ph. kandelakii, Ph. perfiliewi transcaucasicus, Ph. tobbi in northwestern Iran; Ph. major s.l. (=Ph. neglectus), Ph. keshishiani, and Ph. alexandri in southern parts of Iran were molecularly and/or parasitologically positive for L. infantum infections. The zoonotic form of VL (ZVL) caused by L. infantum occurs sporadically in all geographical zones of Iran but in northwestern and southern parts of the country the disease is endemic. DAT as an appropriate and potential tool has been used for sero-diagnosis and sero-epidemiological of VL among humans as well as domestic and wild canines.     

Trichinella Infection in Wildlife of Northeast of Iran

Background

The objective of this investigation was to detect the presence of Trichinella in some carnivores of Mashhad in northeast of Iran and to identify Trichinella species circulating in this area.

Methods

The present study was carried out using muscle tissue collected from 120 stray dogs, 26 wild boars, 25 rodents, two foxes and two hyenas captured in Mashhad City, province of Khorasan Razavi, Iran.

Results

Trichinella larvae were detected in three stray dogs by artificial digestion and compression. All larvae were identified as T. britovi using multiplex PCR.

Conclusion

This is the first report of identification of T. britovi in stray dog in Iran.     

Identification of Echinococcus granulosus Strains in Isolated Hydatid Cyst Specimens from Animals by PCR-RFLP Method in West Azerbaijan – Iran

Background

The aim of this study was DNA extraction from protoscolecses of Echinococcus granulosus and identification of these strains in West-Azerbaijan Province, north western Iran.

Methods

Thirty one livestock isolates from sheep and cattle were collected from abattoirs of the province. To investigate the genetic variation of the isolates, after DNA extraction by Glass beads-phenol chloroform method; PCR-RLFP analysis of rDNA-ITS1 was performed using three different restriction enzymes of Taq 1, Rsa 1 and Alu 1.

Result

Amplified PCR products for all isolates were 1000bp band which is expected band in sheep strains (G1-G3 complex). The results of RFLP analysis also were the same for all isolates. PCR-RFLP patterns restriction enzymes were identical as follows, Rsa1 bands under UV showed two bands approximately 655bp and 345bp. Alu1 bands were as follows: two approximately 800bp and 200bp and Taq1 did not cut any region and bands were approximately 1000 bp in all samples.

Conclusions

Based on PCR-RFLP patterns of ITS1 fragment produced with endonucleases enzyme digestion in animal isolates, it can be concluded that a single strain of E. granulosus (sheep strain or G1-G3 complex) is dominant genotype in this province.     

Hematologic and Clinical Aspects of Experimental Ovine Anaplasmosis Caused by Anaplasma ovis in Iran

Background

Anaplasma ovis infections can cause clinical symptoms in acute phase and lead to huge economic losses in flocks. The aim of the present study was to investigate the hematological and parasitological changes in experimental anaplasmosis in sheep with Iranian strain of A. ovis.

Method

Five male sheep without any blood parasite infection were selected. One hundred ml heparinized blood was collected from splenectomised sheep that showed 6% A. ovis parasitemia. Inoculums of 20 ml blood were administered intravenously to each test animal. Hematological, parasitological and clinical changes of experimental anaplasmosis were studied in 0-38 days post infection.

Result

Parasitemia was detected 3 days post infection and reached its maximum level on the day 12 of experiment in test animals. Then the parasitemia was declined, but the organism could be found persistently until the last day of study. The red cell counts, packed cell volume and hemoglobin concentration were decreased and mean corpuscular volume was increased significantly during the infection period. Reticulocytosis and basophilic stippling were also detected. No significant changes were observed in total and differential leukocyte count and animal body temperature.

Conclusion

Experimental A. ovis infection in sheep resulted in marked normocytic normochromic anemia at the beginning of the infection which became macrocytic normochromic by the development of the disease. There were negative correlations between parasitemia and RBC, PCV and Hb values, therefore hematological assessment can be considered as a practical diagnostic tool in ovine anaplasmosis.