BACKGROUND: Ovine theileriosis is an important hemoprotozoal disease of sheep and goats in tropical and subtropical regions which causes high economic loss in the livestock industry. OBJECTIVES: The aim of this study was the differential detection of Theileria species in sheep using PCR method. METHODS: Two hundred blood samples of sheep were investigated in order to differentially diagnose Theileria species. DNA was extracted from blood samples and DNA samples were amplified using specific primers designed for 18S rRNA, TamS1 and TaSp genes. RESULTS: In this study, from 200 examined samples, 42 samples (21%) were infected by Theileria spp. and none of them were infected by Babesia spp. Moreover, from these 42 positive samples, 24 samples (57.1%) were only infected by T. ovis. 12 samples (28.5%) were only infected by T. lestoquardi, 2 samples (4.7%) were only infected by T. annulata and 4 samples (9.5%) were simultaneously infected by T. lestoquardi and T. ovis. The results of nucleotide sequencing showed that PCR product of 18S rRNA from T. lestoquardi has 99 and 95% similarity with T. annulata and T. ovis respectively. T. lestoquardi and T. annulata showed 86% similarity. Also TaSp gene of T. ovis in comparison with T. annulata and T. lestoquardi showed 96 and 86% similarity, respectively. CONCLUSIONS: In the present study could be shown that the two genes (TamS1 and TaSp) from examined three genes could be used for Theileria species specific diagnosis by PCR.

Four hand-reared, naïve roan antelope, 4 months of age, were exposed to naturally infected pasture on a game farm in Mpumalanga Province, South Africa, where roan are known to die from theileriosis. Various clinical parameters were recorded during this period. The predominant ticks parasitising these animals at the time (January to February), were Rhipicephalus appendiculatus and Rhipicephalus evertsi evertsi adults. After a period of 5 weeks the animals developed signs of clinical theileriosis and were treated with buparvaquone to prevent mortality. Primary hyperplasia of the local draining lymph nodes (Lnn. anorectales) near the feeding site of adult R. evertsi evertsi indicated possible transmission of Theileria sp. (sable) by this tick species. After recovery from theileriosis, these animals were confirmed carriers of Theileria sp. (sable) by PCR (polymerase chain reaction) and DNA probe analysis. Laboratory-bred larvae and nymphs of R. evertsi evertsi and R. appendiculatus respectively, were fed on the ears of these roan antelope. Salivary glands from moulted and prefed adult ticks of each species were dissected and stained for Theileria spp., and the PCR and DNA probe applied to a representative batch of dissected glands. R. appendiculatus adults collected from grass in infected camps were also dissected after prefeeding them on rabbits. Salivary glands of both tick species showed infected acini on staining and were also positive for Theileria sp. (sable) only, on multiprotozoal PCR-screening analysis. There was no statistical significant difference between the infection rate and the intensity of infection between the two tick species. R. appendiculatus ticks collected from grass were also PCR-positive for Theileria sp. (sable).

Malignant theileriosis of sheep is a highly fatal, acute or subacute disease is caused by the tick-borne protozoan parasite, Theileria hirci. In this investigation ten healthy male lambs aged 5-6 months were randomly divided into two groups, A and B and were kept in isolated tick-proof pens. They were treated for internal and external parasite before commencement of the experiment. The lambs were experimentally infected with T. hirci by placing ticks Hyalomma anatolicum anatolicum infected with T. hirci on them. The ticks used in this survey had originally been isolated from sheep and colonies of them were established in an insectarium. Before and after infection rectal temperatures and clinical signs of the lambs were recorded, blood and prescapular lymph node smears were prepared and examined to determine the extent of the parasitaemia, and blood samples were analyzed to evaluate their haemoglobin (Hb) and packed cell volume (PCV) rates. Three days after the commencement of a febrile reaction and appearance of the schizonts in the lymph node smears, treatment of the lambs in Group A with an extract containing the alkaloids of Peganum harmala (wild rue) was commenced. Group B lambs were kept untreated controls. Before treatment there were no significant differences in the rectal temperature, parasitaemia rate, and the Hb and PCV values between animals in the two groups but after treatment significant differences in these values was detected (P < 0.05). After treatment, the clinical signs and parasites in the lymph node smears of the animals in Group A disappeared and they all animals recovered. These parameters in the animals of Group B progressed until their death. Pathological studies showed the characteristic lesions of theileriosis in lambs in Group B, but not in Group A. The results indicate a therapeutic effect of the alkaloids of P. harmala for treatment of ovine malignant theileriosis.

To evaluate the transplacental transfer of Theileria sergenti infection in cattle, we used DNA probes to detect T. sergenti in 6 pregnant cows and their calves. All the animals were monitored by parasitologic, serologic, and polymerase chain reaction (PCR) assays for a predicted 875-base-pair (bp) DNA product and a 684-bp amplicon detected by nested PCR in the blood and spleens of aborted fetuses. An open reading frame (ORF) starting at nucleotide 170 and terminating at position 1021 was shown to code for a polypeptide of 283 amino acid residues. All 6 dams and 5 calves were positive for T. sergenti in all tests. One calf was positive only with nested PCR. We conclude that transplacental transmission of T. sergenti is a significant problem. The relevance of the data in the programmed introduction of new (especially pregnant) animals into established clean herds needs serious consideration with regard to control of theileriosis and other tickborne diseases.

A total of 2803 bloodsamples from ruminant livestock werereceived for diagnosis for parasiticinfections from 2011 to 2015. Theruminant samples were from small holderand commercial farms from the states ofNegeri Sembilan, Melaka, Selangor andthe Federal Territory. The results indicatethe presence of theileriosis, anaplasmosis,babesiosis and trypanosomiasis in theseanimals. The most common parasiteidentified annually is theileriosis in cattle.This information is vital for disease controlstrategies as most blood protozoa causemorbidity and is transmitted by vectorssuch as ticks.

Blood protozoan diseases are significant to animal breeding as theyresult in economic loss due to mortality, reduction in production efficiency and increment in drugs usage. This historical retrospective study was carried out to investigate the most significant blood protozoan diseases, their trends as well as the host range diagnosed by Veterinary Research Institute (VRI) from 1931 to 2010 among Malaysian domestic animals. Conventional techniques such as stained thin blood film, whole blood buffy coatexamination and direct wet smears were utilised for diagnosis from 1931 to 2010. Five most common significant blood protozoan diseases from the domestic animals were identified namely, theileriosis,leucocy tozoonosis, pla smod ia sis, babesiosis and trypanosomiasisrespectively. The setting up of a systematic laboratory service in VRI has enabled more cases of blood protozoan infections to be diagnosed and this has inadvertently led to better understanding and control of the diseases thereby improving the livelihood and reducing economic loss of local farmers.

Investigation was carried out in response to a report of mortality among Jersey crossbred dairy cattle at Therkumedu village, Tirunelveli district which were purchased from Chittoor district, Andhra Pradesh. Clinical examination was carried out in 38 animals. Most of the animals showed signs of general weakness, dullness, anaemia, icteric mucus membrane, lymphadenopathy, acariasis, bruxism, debility and passing semisolid faeces  coated with mucus. Blood smear examination revealed the presence of T. annulata piroplasm and A. marginale inclusions. All the affected animals were treated with Buparvaquone @ 2.5 mg/kg and Oxytetracycline @ 20 mg/kg for 7 days supported with parenteral haematinics (Tribivet) and liver extract. Control of ectoparasites was effected with cypermethrin @ 0.2 per cent as external application and 0.4 per cent spray in animal sheds. All the treated  animals recovered slowly and became normal.