REGULAR ARTICLES Serological evidence of enzootic bovine leukosis in the periurban dairy cattle production system of Al Ain, United Arab Emirates Nabeeha Abdelgaleel D. Hassan 1 & Khaja Mohteshamuddin 1 & Asha Anthony 1 & Ahmad Al Aiyan 1 & Mohamed E. H. Mohamed 1 & Ibrahim M. Abdalla Alfaki 2 & Robert Barigye 1 Received: 22 November 2019 /Accepted: 3 March 2020 # Springer Nature B.V. 2020 Abstract The serostatus of enzootic bovine leukosis (EBL) was determined at three dairy farms and the Al Ain Livestock Market (AALM), within the Al Ain region of Abu Dhabi, UAE. Of the 957 bovine sera tested by ELISA, 657 were from Holstein-Friesians from three dairy farms, and 300 from Bos indicus cattle at AALM. The chi-square homogeneity test (CSHT) and the Marascuilo multiple comparison procedure (MMCP) assessed the level of significance between the proportions of EBL-seropositive cattle (ESPC) across the study farms and AALM, and between the age groups at farms 1 and 3. Overall, the proportion of ESPC was 25.7% at dairy farms and AALM, 37.0% for farms and 1.0% for AALM. Furthermore, the proportions of ESPC at farms 1, 2 and 3 were 54.7%, 0.0% and 26.3% respectively, and statistically significant differences were seen across the farm/farm and farm/ AALM comparisons, and between two age groups at farms 1 and 3. The 37–72-month-old age group showed the highest proportion of ESPC. This is the first serological evidence of EBL in the UAE. As previously reported, the ESPC are compar- atively higher in dairy than Bos indicus cattle. Molecular and more extensive serological studies are needed to further corroborate the present data. Meanwhile, the UAE veterinary authorities will need to formulate national EBL control policies. Keywords Cattle . Enzootic bovine leukosis . Seroprevalence . UAE Introduction Enzootic bovine leukosis (EBL) is an economically important disease of cattle caused by the bovine leukaemia virus (BLV). The latter is an oncogenic retrovirus that is a member of the Deltaretrovirus genus, and the family Retroviridae. The family includes several lymphotropic viruses of humans and animals (Moratorio et al. 2013, pp. 4–11; Polat et al. 2017, pp. 2–16). In about 5% of BLV-infected cattle, the virus is associated with a life-long persistent lymphocytosis that may progress into a ful- minant disease characterized by malignant B cell lymphosar- comas (Moratorio et al. 2013, pp.4–16; Polat et al. 2017, pp. 2– 16). While a larger proportion of BLV-infected cattle remain subclinical (Panei et al. 2013, pp. 1–8; Pandey et al. 2017, pp. 1051–1056), asymptomatically affected animals do play an important epidemiological role through perpetuating a trans- mission risk to in contact cattle (Maresca et al. 2015, pp. 222–226). Besides, while BLV is a primary pathogen of cattle, persistent lymphocytosis and B cell lymphosarcomas have been demonstrated in sheep experimentally infected with the virus (Nekoei et al. 2015, pp. 703–707; Reichert 2017, pp. 1363–1375). Compared with the natural disease in cattle, the experimentally induced form of the disease in sheep has a more rapid onset and higher frequency of persistent lymphocytosis and lymphosarcomas (Nekoei et al. 2015, pp. 703–707; Reichert 2017, pp. 1363–1375). Horizontal BLV transmission is the predominant route of infection in cattle and requires prolonged direct contact be- tween animals and/or an exchange of blood, exudates, or tis- sues (Mekata et al. 2015, pp. 1115–1120). In addition, the role of haematophagous insects (Hasselschwert et al. 1993, pp. 472–473), as well as iatrogenic factors, has been cited in the transmission of BLV in cattle (Dimmock et al. 1991, pp. 230– 233). It is noteworthy that BLV may also be vertically trans- mitted (Oguma et al. 2017, pp. 120–124). As a cattle disease, * Robert Barigye rbarigye@uaeu.ac.ae 1 Veterinary Medicine Department, College of Food and Agriculture, United Arab Emirates University, P.O. Box 15551, Al Ain, UAE 2 Department of Data Analytics in the Digital Era, College of Business and Economics, United Arab Emirates University, P.O. Box 15551, Al Ain, UAE Tropical Animal Health and Production https://doi.org/10.1007/s11250-020-02262-1