Seroprevalence of Bluetongue Virus in Dairy Herds with Reproductive Problems in Sudan

Abstract

The objectives of this cross-sectional study were to determine the seroprevalence of blue tongue virus (BTV) and assess potential risk factors associated with BTV infection in dairy cattle with reproductive problems in Sudan. Serum samples were collected from a total of 784 animals from 37 herds and tested for antibodies against BTV using cELISA. A total of 663 out of 784 (84.57%) sera tested proved positive for BTV antibodies in all farms tested in Khartoum and Gazira States. The prevalence of antibodies was high in both areas being 94.32% in Gazira State and 76.62% in Khartoum State. BTV antibodies prevalence were significantly higher (P < 0.000) in older animals than in younger ones. These rates were also significantly higher in the rainy season (P < 0.000) and in Gazira State compared to Khartoum State. Sex also showed significant (P < 0.000) differences in the seroprevalence, whereby females (74.7%) had higher level than males (9.8%). However, no significant (P > 0.09) variations for BTV seroprevalence were observed between breeds. The BTV antibodies prevalence in infertility cases (86.6%) was not significantly different from that found in abortion (74.3%) or neonatal death (66.7%) cases. The high seroprevalence of BTV recorded herein calls for control strategy to be implemented.

Serological Investigations of Bluetongue Virus (BTV) among Sheep and Goats in Kassala State, Eastern Sudan

“…In addition, Kassala state shares long international borders with Eritrea with no strict restriction on animals' movement across the borders which may allow introduction of infected animals into the localities. Similar high seroprevalence of BTV infection in various animal species was reported in several states in Sudan [ 28 , 29 , 31 , 36 , 39 ] and in countries around or near Sudan such as Libya (48.4%) [ 44 ]; Egypt (16.9%) [ 45 ]; Ethiopia (30.6%) [ 42 ]; and Saudi Arabia (47.3%) [ 46 ]. In addition, earlier epizootiological surveys also showed high prevalence rates for BTV seropositivity in Iran (93.5%) and Southern Turkey (88%) [ 47 , 48 ].…”

“…In Sudan, an early serological survey showed that BT infection is generally widespread among all domestic ruminants [ 27 ]. Subsequent serological surveys for BTV group-specific antibodies further confirmed the widespread nature of the infection in various parts of the country [ 28 , 29 , 31 , 36 , 39 ]. The present study showed that the overall seroprevalence of BTV group-specific antibodies in sheep and goats in Kassala state was substantially higher than previously recorded in other regions of Sudan.…”

“…Fayza et al [ 35 ] explained the role of apparently healthy cattle as a reservoir of BTV to sheep in Sudan, and Elzein [ 31 ] reported that susceptibility of camels to BTV infection was lower than that of other ruminant species in the country. Elhassan et al [ 36 ] showed that BTV antibodies in cattle were quite prevalent in Gezira (Central Sudan) and were particularly high in older animals, females, cases of infertility, and during rainy season.…”

Serosurveillance and factors associated with the presence of antibodies against bluetongue virus in dairy cattle in two eco-zones of Nepal

“…This is not surprising, because older cattle have had more time for exposure to BTV than younger animals. Studies in other countries have also shown higher seroprevalence in older cattle (17,18,19,20,21).…”

Selection for Favorable Health Traits: A Potential Approach to Cope with Diseases in Farm Animals

“…Bluetongue causes huge economic losses to the sheep industry due to high mortality and morbidity, as well as the trading of animals associated with its outbreak. The prevalence of bluetongue was 19% in Italy [ 26 ], but in Sudan, the prevalence has been as high as 94% [ 27 ]. In 2007, the cost of the bluetongue disease for sheep breeding farms in the Netherlands was estimated at 12.6 million euros [ 28 ].…”