ABSTRACT
Objective: To determine the biochemical and acute phase proteins changes in sheep experimentally infected with Anaplasma ovis (A. ovis). Methods: One Iranian sheep naturally infected with A. ovis (parasitemia 0.02%) but with no other blood parasites based on blood smear and polymerase chain reaction methods was selected as donor, and it was splenectomized to induce high level of parasitemia. Then, three weeks after splenectomy when parasitemia was 6%, donor's blood was intravenously administered to each recipient animal. Five 5-6 months old Iranian male sheep without any blood parasites were selected as recipient animals. The percent of parasites, packed cell volume, serum biochemical parameters (urea, creatinine, bilirubin, aspartate aminotransferase activity, cholesterol, total protein, albumin, globulin, Fe), acute phase proteins (haptoglobin, total iron binding capacity, fibrinogen), were evaluated in sheep before and after being experimentally infected with A. ovis (until day 38). In addition, body weights of sheep were measured on days 0, 20 and 38. Results: In recipient sheep, microscopic examination of erythrocytes revealed a significant rise of parasitemia on days 12 and 15. The lowest level of packed cell volume in sheep was seen on day 15 post infection. A significant rise existed in mean urea and bilirubin (total, direct and indirect) on days 15 and 20. The increase of indirect bilirubin level was higher than direct bilirubin. Furthermore, serum Fe significantly increased on days 20 and 23. The mean total protein concentration significantly increased on day 38. A significant increase was found in the serum globulin concentration from days 20 and 27 to 38. Maximum values of haptoglobin were observed on days 27 and 30. Moreover, aspartate aminotransferase activity (from days 20-30) and cholesterol concentration (on day 20) significantly decreased. However, no significant changes were found in other parameters. Conclusions: Experimental ovine anaplasmosis caused by A. ovis could be associated with some changes in measured parameters, which presumably could be helpful for evaluation on staging of disease.
ABSTRACT
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. 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. 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 Hpall 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. 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 proportion 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 regions