Seroprevalence, clinical incidence, and molecular and epidemiological characterisation of small ruminant lentivirus in the indigenous Passirian goat in northern Italy

Abstract

Eight dairy flocks, comprising a total of 323 indigenous Passirian goats from northern Italy, were examined to determine the seroprevalence and clinical incidence of small ruminant lentivirus (SRLV) infections and to identify the SRLV subtypes. The seroprevalence was 81.5% (55-95%). The clinical incidence was 2.5% (0-8.3%) and was apparently low due to the practice of culling clinically affected animals. Phylogenetic analysis of eight PCR fragments (one sample from each flock) revealed that all proviruses belonged to the SRLV subtype B1, which suggests a common source of infection. Subtype B1 being the only circulating SRLV, coupled with the fact that mixed herd systems are very rare in South Tyrol, gives hope that an eradication programme in goats can be successful even without including sheep as long as sheep are kept strictly and permanently isolated.

Eradication of caprine arthritis encephalitis virus in the goat population of South Tyrol, Italy: analysis of the tailing phenomenon during the 2016–2017 campaign

“…1,15 The drastic decrease in prevalence achieved in the initial phase of the South Tyrolean program along with the disappearance of clinical cases confirms that the main source of infection in South Tyrol was initially related to SRLV B-infected goats. 9 However, in this later phase, the described data confirm that, Positive farms = farms with at least one positive goat by the IDvet screening ELISA. The percentage of nonconclusive (NC) results is statistically lower (34.4% vs. 44.0%, p = 0.029) on multispecies farms than on monospecies farms.…”

“…1,15 The drastic decrease in prevalence achieved in the initial phase of the South Tyrolean program along with the disappearance of clinical cases confirms that the main source of infection in South Tyrol was initially related to SRLV B–infected goats. 9 However, in this later phase, the described data confirm that, on multispecies farms, sheep may serve as a source of SRLV infections in goats. The fact that IDvet-negative/IN3-positive screening ELISA samples have a distinct profile in the genotyping ELISA suggests pitfalls in the sensitivity of the IN3 screening ELISA.…”

Infection with Foamy Virus in Wild Ruminants—Evidence for a New Virus Reservoir?

“…The most important alphaherpesvirus, bovine herpesvirus 1 (BoHV) have also been reported to infect almost 40% of cervids in Poland [24], and a low percentage of the bison population [25]. Inter-species infections with ruminant retroviruses have been also reported previously: Bovine leukemia virus (BLV) infections have occasionally been described in European bison [25] or alpaca (Vicugna pacos) [26], while small ruminant lentiviruses (SRLV) infections have been found in Rocky Mountain goats (Oreamnos americanus) [27], Passirian goat in northen Italy [28] and recently in red deer (Cervus elaphus) and muflon (Ovis aries musimon) in Spain [29]. All reported cases are most likely due to the spill-over from domestic animals, acquired similarly to the well documented case of SRLV infection of endangered wild ibex (Capra ibex) in the French Alps, which was probably a result of sharing grazing grounds with a small herd of heavily infected goats [30].…”

Small Ruminant Lentiviruses (SRLVs) Break the Species Barrier to Acquire New Host Range

“…In Europe, bluetongue virus (BTV) recently emerged and became enzootic in livestock [65,88]. Wild ungulates were proved to be receptive to the SRLVs in many regions and various diseases affecting new hosts have already been identified in wildlife [11,89]. The successful experimental and natural infections of wild small ruminants, such as ibex ( Capra ibex ) and mouflon ( Ovis gmelinii ) with SRLVs provide proof that these wild ruminants are susceptible for CAEV infection.…”