Feline leukemia virus outbreak in the critically endangered Iberian lynx (Lynx pardinus): high-throughput sequencing of envelope variable region A and experimental transmission

Abstract

The Iberian lynx is the most endangered felid species. During winter/spring 2006/7, a feline leukemia virus (FeLV) outbreak of unexpected virulence killed about 2/3 of the infected Iberian lynxes. All FeLV-positive animals were co-infected with feline hemoplasmas. To further characterize the Iberian lynx FeLV strain and evaluate its potential virulence, the FeLV envelope gene variable region A (VRA) mutant spectrum was analyzed using the Roche 454 sequencing technology, and an in vivo transmission study of lynx blood to specified-pathogen-free cats was performed. VRA mutations indicated weak apolipoprotein B mRNA editing enzyme and catalytic polypeptide-like cytidine deaminase (APOBEC) restriction of FeLV replication, and variants characteristic of aggressive FeLV strains, such as FeLV-C or FeLV-A/61C, were not detected. Cats exposed to FeLV/Candidatus Mycoplasma haemominutum-positive lynx blood did not show a particularly severe outcome of infection. The results underscore the special susceptibility of Iberian lynxes to infectious diseases.

Glomerular Injury in Domestic Cats and the Iberian Lynx (Lynx pardinus): A Comparative Review

“…Our group also reported a generalized immune depletion apparently unrelated to infectious agents or other systemic diseases after evaluating lymphoid tissues in a representative portion of the population during the years 1998-2003 (Peña et al, 2006). A feline leukemia virus infection outbreak in the Doñana National Park population of Iberian lynxes was reported during a six month period between 2006 and 2007 (Meli et al, 2010(Meli et al, , 2011. During this period, six animals died presumably due to the infection (Meli et al, 2011).…”

“…During this period, six animals died presumably due to the infection (Meli et al, 2011). Sequence analysis revealed homology with a strain originally identified in domestic cats suggesting co-infection between species (Meli et al, 2011;Geret et al, 2011). Prior to this time, the reported prevalence of feline leukemia virus in the same population was relatively low (Luaces et al, 2008) and evidence of lesions or death directly associated with the viral infection was unknown.…”

“…A feline leukemia virus infection outbreak in the Doñana National Park population of Iberian lynxes was reported during a six month period between 2006 and 2007 (Meli et al, 2010(Meli et al, , 2011. During this period, six animals died presumably due to the infection (Meli et al, 2011). Sequence analysis revealed homology with a strain originally identified in domestic cats suggesting co-infection between species (Meli et al, 2011;Geret et al, 2011).…”

Quantification of the humoral immune response and hemoplasma blood and tissue loads in cats coinfected with ‘Candidatus Mycoplasma haemominutum’ and feline leukemia virus

“…Following the principle of the 3Rs (reduce, refine, replace), they were also part of another study that aimed to assess the diseaseinducing potential of the FeLV strain present in the Iberian lynx [13]. All of the animal experiments were performed according to the law and were officially approved by the veterinary office of the canton of Zurich (TVB 159/160/2010), as required by Swiss law.…”

“…The cats were also part of another study for which they were coinfected with FeLV; the details of the FeLV portion of this study were reported elsewhere [13]. Because coinfections with FeLV and feline hemoplasmas have been reported in domestic cats [14e16], and several studies even found an increased prevalence of FeLV infection in CMhm-infected cats [17e20], the chosen model mirrors the field situation.…”