Bovine leukemia virus (BLV) causes enzootic bovine leukosis (EBL), the most common neoplastic disease in cattle worldwide. The first EBL outbreak in Egypt was reported in 1997. To date, there are few studies regarding BLV diagnosis using only serological detection and no studies investigating the distribution of BLV provirus, which is the retroviral genome integrated into the host genome, in Egypt. The genetic characteristics of Egyptian BLV strains are also unknown. Therefore, we aimed to detect BLV provirus and determine BLV genetic variability among dairy cattle in Egypt. We collected 270 blood samples of dairy cattle from 24 farms located in five provinces in Egypt. Out of the 270 samples, 58 (21.5%) were positive for BLV provirus. Phylogenetic analysis based on 18 420-bp selected sequences out of 50 isolates of the BLV env -gp51 gene demonstrated that Egyptian BLV isolates were clustered into genotype-1 and-4, among 11 genotypes detected worldwide. Furthermore, phylogenetic analysis and alignment of the 501-bp sequence of the env- gp51 gene revealed that at least six genetically different strains are present in Egypt. Genotype-1 isolates comprised four different strains (G1-a, G1-b, G1-c, and G1-d) and genotype-4 isolates included two different strains (G4-x and G4-y). Moreover, in one farm with 100% infection rate, we identified three isolates of G1-a strain, 35 isolates of G4-x strain, and two isolates of G4-y strain. Overall, this study provides the new report on molecular prevalence of BLV in Egypt and records the coexistence of BLV genotype-1 and-4 in Egyptian cattle.
Background: Toxoplasma gondii and Neospora caninum are major protozoan parasites of worldwide distribution and significance in veterinary medicine and, for T. gondii, in public health. Cats and dogs, as final hosts for T. gondii and N. caninum, respectively, have a key function in environmental contamination with oocysts and, thus, in parasite transmission. Very little is known about the prevalence of T. gondii infections in dogs and cats in Egypt, and even less about the prevalence of N. caninum in the same hosts. Methods: In the current study, 223 serum samples of both dogs (n = 172) and cats (n = 51) were investigated for specific antibodies to T. gondii and N. caninum using commercially available ELISAs. A risk factor analysis was conducted to identify factors associated with seropositivity. Results & discussion: Exposure to T. gondii was reported in 23.3% of the dogs and in 9.8% of the cats, respectively. In addition, N. caninum-specific antibodies were recorded in 5.8% of dogs and in 3.4% of cats. A mixed infection was found in two dogs (1.2%) and in one cat (2%). Antibodies to T. gondii in dogs were significantly more frequent in dogs aged 3 years or more and in male German Shepherds. As this breed is often used as watchdogs and was the most sampled breed in Alexandria governorate, the purpose “watchdog” (compared to “stray” or “companion”), the male sex, and the governorate “Alexandria” also had a significantly higher seroprevalence for T. gondii. No factors associated with antibodies to N. caninum could be identified in dogs, and no significant factors were determined in cats for either T. gondii or N. caninum infection. Our study substantially adds to the knowledge of T. gondii infection in dogs and cats and presents data on N. caninum infection in cats for the first and in dogs in Egypt for the second time.
IntroductionNeospora caninum and Toxoplasma gondii are closely related obligate intracellular protozoan parasites. They are considered to be the major causes of infectious abortions and congenital abnormalities in livestock worldwide resulting in huge economic losses. Currently, there are no reports on the prevalence of neosporosis or toxoplasmosis in cattle in Beheira, Egypt's most important region for cattle industry.MethodsThe current study investigated the presence of anti-N. caninum and anti-T. gondii antibodies in apparent healthy cattle from eight localities representing the whole area of Beheira. A total of 358 plasma samples were randomly collected from 6 dairy and 10 beef farms and analyzed by commercially available ELISAs. Production type (dairy versus beef), sex (female vs male), age (< 3 years, 3–5, and > 5 years old), breed (mixed vs Holstein vs Colombian Zebu), and location (various locations) were assessed as risk factors for N. caninum and T. gondii infections.Results and discussionOf the samples, 88 (24.6%) and 19 (5.3%) were positive for anti-N. caninum and anti-T. gondii antibodies, respectively, and mixed infection was detected in 7. Of the 16 herds, 6 dairy and 7 beef herds were positive for antibodies to N. caninum. Antibodies to T. gondii were detected in 4, and 5 of dairy and beef herds, respectively. Production type (dairy) and, therewith, sex (female), age (aged over 5 years), and location were considered as risk factors for N. caninum infection. No factors statistically associated with T. gondii infection were identified. Overall, this study provided the first serological detection of N. caninum and T. gondii infections in cattle from Beheira, demonstrating the endemicity of both parasites in the main cattle rearing region of Egypt. This study also confirmed earlier reports of N. caninum being more present in dairy cattle than in beef cattle. Routine monitoring of N. caninum and T. gondii infections and the implementation of control strategies are urgently needed.
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