Prevalence of Small Ruminant Lentivirus Infections in Sheep and Goats in Some Regions of Vojvodina Province

Abstract

Small Ruminant Lentivirus causes a chronic lifelong, multisystemic diseases in sheep and goats with or without clinical manifestation. Maedi-visna virus (MVV) and Caprine arthritis encephalitis virus (CAEV) are often considered together as small ruminants lentivirus (SRLV) due to their phylogenetic correlation and the interspecies transmission between sheep and goats.
 During the period of four years, from 2015-2018, an annual monitoring was done on male animals (rams and bucks) used for breeding, for determination of antibodies against SRLV with ELISA serological method. In total, serum samples from 6732 animals were analyzed.
 During the study period, seroprevalence for small ruminant lentivirus has rised from 4,17% to 16,21%, with an overall value of 12% for the whole period. Over the years seroprevalence has been changing with increasing tendency. The highest seroprevalence in rams was in 2018, when the largest number of samples was examined. In bucks, the highest number of positive samples was found in 2015. From 2014 until 2018, the overall seroprevalence in rams and bucks has increased significantly. From the study results it can be seen that annual monitoring program is very important and has to be held in the future in order to have the disease under control. The program helps in rising the awareness and knowledge of the owners about SRLV and the importance of breeding seronegative animals.

Worldwide Prevalence of Small Ruminant Lentiviruses in Sheep: A Systematic Review and Meta-Analysis

“…Interestingly, some infected areas show a 100% prevalence in flocks while the infection is just about 20% in animals, suggesting that the multiplying factor could be higher than two-fold under certain conditions. Increased prevalence is related to any activity that may imply prolonged close contact between animals favoring horizontal transmission such as intensive production system [ 1 , 65 ], transportation, or sharing milking machines [ 43 , 91 ]. Flock size might also play a role as higher numbers of animals per flock relate to higher prevalence [ 59 , 61 ].…”

“…Age also seems to be related to higher prevalence of infection, with a non-linear increase that reaches the maximum at about four years of age [ 59 , 61 , 65 ]. Influence of sex in prevalence is not that obvious, some studies indicate males being more predisposed than females [ 43 ], whereas others indicate non-significant differences [ 57 , 59 , 63 ].…”

Pathological, molecular, and serological study of small ruminant lentiviruses in Jordan

“…The results our study presented here reveal that SRLVs sheep individual seropositivity in northern governorates of Jordan (40.1%, n = 633) is significantly higher than that in other six countries where the same commercial indirect MVV/CAEV ELISA kit was used (3.4%, n = 2801 in Czech Republic [32], 34.0%, n = 147 in KSA [33], 19.9%, n = 3903 in Serbia [34], 3.2%, n = 494 in Ethiopia [35], 16.2%, n = 210 in Iraq [36], and 2%, n = 359 in Costa Rica [37]). SRLVs goat individual seropositivity (18.5%, n = 173) in northern governorates of Jordan was significantly lower than that in KSA (38.8%, n = 103) [33] and not significantly higher than that in Czech Republic (14.1%, n = 609) [32] and Serbia (13.2%, n = 1136) [34] (Figure -4). In Lebanon, the individual and herd seropositivity of Maedi in Awassi sheep were higher that the seropositivity in our study (71% and 100%, respectively) [20].…”