avian & livestock assay data sheet
Jaagsiekte sheep retrovirus (JSRV)
- Ultrasensitive qualitative detection of jaagsiekte sheep retrovirus
proviral DNA by real time PCR.
Infection of sheep by jaagsiekte sheep retrovirus
(JSRV) can result in ovine pulmonary adenocarcinoma (OPA), a
contagious cancer. The disease was initially described in 1915
in South Africa and was subsequently found to be present
worldwide. JSRV is a betaretrovirus, within the Retroviridae
This virus is transmitted between animals by
close contact, mainly through aerosolized particles. Close
breeding conditions are of major importance for the
dissemination of the virus. Infected animals may take 2 to 4
years to develop the full spectrum of symptoms, but in some
cases, the cancer may be diagnosed as early as a few months
after birth. The onset of the disease seems to be age-dependent.
Thus, animals may be carriers of the virus without symptoms and
become potential viral reservoirs
JSRV is phylogenetically related to the enzootic
nasal tumor virus (ENTV) which is responsible for nasal
adenocarcinoma, a contagious tumor of the nasal mucosa affecting
sheep and goats. In ENTV-infected animals, epithelial cell
proliferation causes continuous nasal discharge, respiratory
distress, exophthalmos and skull deformations. Co-infection of
ENTV and JSRV has been reported.
Detection of JSRV in sheep is complicated by
the fact that a family of endogenous retroviruses, enJSRV
(endogenous JSRV) closely related to JSRV, is present in the
genomes of domestic and wild sheep and goats. JSRV and enJSRV
genomes are highly similar with 90–98% homology in deduced
amino-acid sequences. Endogenous retroviruses are vertically
transmitted as stable Mendelian genes in the germline of most
eukaryotes. These endogenous retroviral sequences derive from
the integration of exogenous viruses into host genomes, followed
by genetic stabilization through accumulation of mutations.
These endogenous retroviral sequences are not active and their
significance is not clear. However, their similarity to
exogenous viral sequences is a factor in the design of PCR
primers for detecting JSRV in these host species.
Currently, good serological methods to
detect JSRV are not available. Molecular detection by PCR is the
most important tool to screen animals for infection by this
virus (Zhang et al., 2014).
Help confirm the disease causing agent
Identify JSRV carriers
Screen research materials for the presence of JSRV
Help ensure that animal groups are free of JSRV
Early prevention of spread of the virus among animals
Minimize human exposure to the virus
Safety monitoring of biological products that derive from
K., Kong, H., Liu, Y., Shang, Y., Wu, B. and Liu, X. (2014)
Diagnosis and phylogenetic analysis of ovine pulmonary
adenocarcinoma in China. Virus Genes, 48:64–73.
Nasal swabs, or 0.2 ml whole blood in EDTA (purple top) or ACD
(yellow top) tube, or 0.2 ml fresh, frozen or fixed tissue.
For specimen types other than those listed here, please call to
confirm specimen acceptability and shipping instructions.
For all specimen types, if there will be a delay in shipping, or
during very warm weather, refrigerate specimens until shipped
and ship with a cold pack unless more stringent shipping
requirements are specified. Frozen specimens should be shipped
so as to remain frozen in transit. See
for more information.
Turnaround time: 2 business days
Methodology: Qualitative real time PCR