All samples which have antibody titer 20 are considered positive. signs of reproductive disease. 1. Introduction Toxoplasmosis is one of the most common human parasitic infections worldwide with an estimated prevalence in 1-2 billion people [1]. Toxoplasmosis is a zoonotic disease caused Tbp by a sporozoan parasite, infection [9]. Limited information is available on the prevalence of toxoplasmosis in man and animals in Sudan. Camel toxoplasmosis was first reported in Sudan by El Din et al. [10] who recorded an infection rate of 54%. Afterwards Bornstein and Musa [11] and Elamin et al. [12] reported 22.5% and 11.8% in Sudanese camels, respectively. A more recent study recorded prevalence rates of toxoplasma antibodies of 20%, 32%, and 57.5% in camels, cattle, and sheep, respectively [13]. Prevalence rates of up to 73% were recorded in childbearing age women and up to 100% in camel herders in Sudan [14C17]. The present study was carried out to assay seroprevalence of in dairy cattle herds with reproductive problems and to determine risk factors associated with the infection in two states, namely, Khartoum and Gazira of Sudan. 2. Materials and Methods A total of 181 (168 females and 13 males) serum samples were taken from dairy CHR-6494 cattle herds with reproductive problems such as abortion, infertility, and stillbirth. Dairy herds were raised under semi-intensive husbandry systems in farms around Khartoum State (Khartoum, Khartoum North, and Omdurman) and Gazira States (Al Kamleen and Wad Madani). Blood was collected from cattle by vein puncture of the jugular vein. Sera were harvested following centrifugation of clotted blood, labeled, and stored at ?20C until tested. Antibodies to were tested by indirect enzyme linked imunosorbent assay (iELISA). A herd was considered positive for antibodies were purchased from Lsivet (Nouzilly, France). Positive serum samples will present yellow colour; the colour visualized in each well is proportional to the titer of antibody specific to present in the diluted sample (1/400). All samples which have antibody titer 20 are considered positive. 2.2. Statistical Analysis The serological results and other information gathered during this investigation such as season, location, breed, sex, and age of the sampled animals were edited and analyzed statistically using statistical package (SPSS version 13). To identify the association of the risk factors with the specific seroprevalence, the chi-square ( 0.05. 3. Results 3.1. Herd Infection Level Out of 29 herds tested at both states, 13 (44.8%) proved to be positive for antibodies by ELISA. The result showed that 10 (50%) out of the 20 herds in Khartoum State and 3 (33.3%) out of nine herds in Gazira State were positive with the highest herd prevalence (57.1%) being detected in Khartoum North locality (Khartoum State) (Table 1). Table 1 Herd level prevalence of antibodies in cattle in Khartoum and Gazira States detected by ELISA. Area antibodies using ELISA. The overall prevalence of in both states was 13.3% (24/181). The prevalence rate was 12.7% (17/134) in Khartoum State and the prevalence according to the locality was as follows: 12.9% (8/62), 14% (6/43), and 10.3% (3/29) were recorded for Khartoum, Khartoum North and Omdurman localities, respectively. In Gazira State the prevalence rate was 14.9% (7/47) and positive samples were detected in Alkamleen 25% (2/8) and Wad Madani 12.8% (5/39) localities (Table 2). Table 2 Seropositivity to in cattle from different locations in Khartoum State and Gazira State detected by ELISA. Positive 0.05) higher (36.4%) in animals less than one year old than those above two years (12.8%). Moreover, significantly ( CHR-6494 0.05) higher seroprevalence of was observed in males (30.8%) than in females (11.9%), but there was no significant relationship between antibodies prevalence and breed, location, season, or signs of reproductive disease (Table 3). Table 3 Influence of some risk factors on seroprevalence of in cattle using ELISA in Khartoum and Gazira States. 0.05). 4. Discussion Until now insufficient data are available on CHR-6494 cattle toxoplasmosis in the world, and there have been limited number of reports on cattle toxoplasmosis from Sudan. The overall seroprevalence of toxoplasmosis reported in the present study in Sudan using ELISA (13.3%) is higher than that reported for cattle in China (2.3%) [18] and Vietnam (10.5%) [19] but is comparable to that reported in Iran (15.91%) [2] and lower than that (27.9%) recorded in The Netherlands [20]. The differences in prevalence rates between countries may.