الفهرس 
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Abstract
Camels are usually infected by various protozoon parasites as Trypanosoma evansi- Babesia spp.- Theileria spp., Toxoplasma gondii and Neospora caninum which cause serious diseases and threat their life and resulted in serious economic losses.
This study aimed to detect rapid, specific and sensitive serological and molecular tools (PCR), for detection of different blood parasites and hidden tissue parasites infecting camels so enabling to diagnose the different protozoa in early and subclinical stages, and also to determine the prevalence of each protozoon parasite. .
Blood samples were collected from 700 camels of two breed (370 Baldy and 330 Sudani) at different ages varying from 1 - ≤10 years slaughtered in Toukh slaughter house during the period extended from September 2014 to Augst 2015. The samples were collected on EDTA tube and labeled with (serial number, breed and age of the camel). Samples were examined microscopic examination by Gimesa stained blood smears and PCR examination to evaluate the efficacy of each method in detecting different blood parasites. 50 out of 700 blood samples which subjected to molecular examination (PCR) for detection of DNA of Neospora caninum.
Also randomly 120 blood samples were collected without anticoagulant in clean, dry tubes for serum separateion and examined serologically by IHAT and IELISA for detection of Toxoplasma gondii in camels.
Out of 700 blood samples from camels of different ages and breeds through one year revealed that 48 were infected and the infection ratee of blood parasites were 6.8%. The detected blood parasites were Trypanosoma evansi in 8 camels (1.14%) and Babesia spp. in 33 out of the examined camels (4.7%), Theileria spp. in 3 camels (0.4%), Anaplasma marginale detected in 2 camels (0.3%) and mixed infection with both Babesia spp. and A. marginale was detected in 2 camels (0.2%).
The highest infection rate was recorded in autumn (10.3%), followed by summer (7.8%), while the lowest infection rate was recorded in spring (3.5%).
The infection was higher in Baldy breed than Sudani breed with percentages of 9.18% and 4.84% respectively, the infections ratee was higher in camels aged from ≥5 years than those aged from ≤5years with percentage of 8.33% and 4.54%, respectively.
Molecular examination (PCR) of 100 samples selected from negative stained blood smears revealed that the total infection ratee of blood parasites was 18 %; including T. evansi in (14%) and Babesia spp. in (2%). Mixed infection with both blood parasites was detected in 2 camels (2%).Theileria spp. was not recorded. .
Serological examination of T. gondii by using IHAT revealed that antibodies (IgG/ IgM) were detected in 6 (5%) out of 120 tested serum samples were sero-positive.
The infection was nearly similar in the different season of the year, as it was 6.7% in both autumn and winter. The lowest infection rate (3.3%) was recorded in both summer and spring. .
The prevalence of T. gondii was higher in Baldy than Sudani breed which were 6.67% and 3.33%, respectively, there was no difference in the prevalence of infection regarding to the age of the examined camels. While using IELISA for detection of IgG of T. gondii showed that out of 120 tested serum samples 63 (52.5%) were sero-reactive .
Comparateive evaluation between results of IHAT and IELISA cleared that IELISA test was more sensitive than IHAT for detection of T .gondii in camels. IELISA gave ten times positive more than IHAT, as the infection rate was 52.5% and 5% by IELISA and IHAT, respectively.
Examination of 50 blood samples of camels by PCR method for detection of Neospora caninum DNA revealed that 12 samples were positive with total incidence 24 %.The peak of infection was recorded in summer season (57.1%) and lowest infection in autumn (8.3%) and no infection was recorded in winter. .
The infection rate was nearly similar in both Baldy and Sudani breed that were 24.2 and 23.5%, respectively. The infection was higher in camels of ages ≥5 year than camels of ages ≤5 year with percentage of 27.8 and 14.3%, respectively. .
Conclusion
1- Microscopic examination of blood protozoan parasites has low sensitivity, thus making it difficult to detect parasites in blood film during low parasitemia in the carrier animals or in sub -acute infection, so we concluded that PCR provides a simple, rapid, highly sensitive and specific method for detection of camels blood parasites and can be used as a valuable tool during epidemiological surveys and control programs.
2- IELISA and PCR-sequencing are highly sensitive techniques for detection of the Toxoplasma gondii antibodies and Neospora caninum DNA, respectively which are difficult to be diagnosed using microscopic examination.
3-This high prevalence of Toxoplasma in the present study is a serious result as it not only affects the development of the livestock industry but is also an important infective source for human toxoplasmosis
4-It was the first time in Egypt to apply PCR application and sequencing assay for diagnosis of N. caninum in blood of camels in Egypt.