Addressing epidemiological gaps: seroprevalence and management risk factors of Bovine Leukemia Virus in small scale dairy cattle in Chitwan district, Nepal (2017)

Bovine leukemia virus (BLV), an oncogenic deltaretrovirus notifiable to the World Organization for Animal Health, lacks baseline serological data in Nepal despite documented seroprevalence of up to 9.1% in neighboring India. This cross-sectional study screened 368 backyard dairy cattle across five Village Development Committees in Chitwan District in 2017 using a validated indirect ELISA (IDEXX Leukosis Serum X2). Overall seroprevalence was 0.54% (2/368; 95% CI: 0.07-1.95%), with both positives confined to Mangalpur VDC (2.74%; 95% CI: 0.32-9.19%). Breed, age, parity, and clinical history were not significantly associated with seropositivity. Shared hypodermic needle use and shared rectal palpation gloves during artificial insemination showed significant co-occurrence with seropositivity (Fisher’s exact p = 0.007 and p = 0.034, respectively), reported descriptively given the small case count. These findings establish Nepal’s first BLV epidemiological baseline, consistent with a pre-enzootic introduction phase, and identify iatrogenic practices as priorities for future surveillance. The data set contains BVL points, questionaire answers, questionaire, study site with results (Figure 1 and 2).