Vector identification and clinical, hematological, biochemical, and parasitological characteristics of camel (Camelus dromedarius) theileriosis in Egypt

Abstract

The objectives of the present study were to identify a possible tick vector and to determine the prevalence of camel theileriosis in Egypt using blood smears stained with Giemsa's stain and PCR assay. Hemogram and serum biochemical constituents were also investigated. A total of 243 camels, aged 3-5 years, were examined. The results revealed that 75 (30.86 %) camels were infected with Theileria spp. of Giemsa-stained blood smears. Hyalomma dromedarii was identified as the carrier tick of Theileria spp. Multinucleated sporoblast and free sporozoite were observed in the salivary gland smears from collecting ticks. PCR result revealed that Theileria annulata was the most abundant in camels (60 %) followed by Theileria spp. (10 %). Macrocytic hypochromic anemia was recorded in the infected camels with T. annulata. Leukocytosis, neutrophilia, eosinophilia, and lymphopenia were also observed in the infected group. In the serum of infected camels, total proteins, albumin, β-globulin, and A/G ratio were significantly decreased (P < 0.05); however, total globulins and α- and γ-globulins were markedly increased (P < 0.05). The activity of aspartate aminotransferase and the levels of glucose, creatinine, and high-density lipoprotein cholesterol were markedly increased (P < 0.05) in the infected group. In contrast, triglycerides and total cholesterol concentrations were significant decreased (P < 0.001) in the infected group. In conclusion, a high prevalence of camel theileriosis was recorded in apparently healthy camels. H. dromedarii commonly infested these camels and were found infected with the transmissible forms of Theileria, indicating a role in transmission. Camels infected with T. annulata induced alterations in the cellular and biochemical constituents.

Blood Parasites in Camels (Camelus dromedarius) in Northern West Coast of Egypt

“…By using PCR assay, 71.9% of investigated camels were having theileriosis caused by Theileria sp. and the incidence of infection was 71.4% in females and 73.3% in males in agreement with those previously reported [44][45][46][47]. Higher and lower rates of Theileria camelensis ranged from 6.9% to 75% were recorded in Egypt by different authors [43,[46][47][48][49].…”

Identification of 12 Piroplasms Infecting Ten Tick Species in China Using Reverse Line Blot Hybridization

“…In our study, T. annulata infections were found in 3 Hy. asiaticum ticks collected from camel, consistent with studies that reported T. annulata infection in Hyalomma tick parasitizing camels and T. annulata being the most abundant piroplasm in camels (El Kammah et al, 2001;Youssef et al, 2015). Our finding further confirms the evidence of low host specificity of T. annulata.…”

Current status of tropical theileriosis in Northern Africa: A review of recent epidemiological investigations and implications for control

“…As detailed in Table , H. dromedarii was described for the first time in 1990s as a ‘new’ natural vector of T. annulata in Mauritania (Jacquiet, Colas, Cheikh, Thiam, & Ly, ; Jacquiet et al., ). Subsequently, a report from Egypt implicated this tick in the transmission of T. annulata on the basis of molecular detection in camels and microscopic observation of the parasite in the tick salivary glands (Youssef et al., ). In addition, in Sudan H. dromedarii has also been implicated as possible vector of T. annulata on the basis of epidemiological observations (Ahmed in Guma et al, ; Mohammed et al., ) and experimental findings (Mustafa et al., ).…”