RESUMEN
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.
RESUMEN
Nitrite intoxication occurs frequently in ruminants and equines. The most common treatment of this disorder is administration of 1% methylene blue, although the use of some antioxidant agents e.g. vitamins and complementary treatment may also be useful. The aim of this study was to evaluate the in vitro antioxidative effects of some vitamins on methemoglobinemia induced by sodium nitrite. For this purpose the blood sample of a healthy dairy cattle was pre-incubated with three different concentrations (5, 10, 20 mmol L(-1)) of each vitamin (E, C, B1, A and a combination of vitamin E and vitamin C) as antioxidant agent at 4 (°)C for 24 hours. A control group with normal saline instead of vitamin was applied. Then, all samples were treated with sodium nitrite (10 mmol L(-1)) as an oxidant agent for 10 minutes and the level of methemoglobin formation was measured spectrophoto-metrically. The results revealed that the level of methemoglobin decreased significantly (P < 0.05), when vitamin E (10 and 20 mmol L(-1)) and vitamin C (5 mmol L(-1)) was applied to the tests, separately. Vitamin C at the concentration of 20 mmol L(-1), was not effective, but it even increased methemoglobin formation significantly. Combination of vitamin E and C was significantly effective at concentration 5 mmol L(-1), but not at concentration 10 and 20 mmol L(-1). Vitamin A and vitamin B1 were not effective in any concentration. It was concluded that vitamins especially vitamin C and E can reduce oxidative effects which induced methemoglobin formation in vitro and could be used as an alternative medication.