Seroprevalence of feline leukemia virus present in populations of wild and captive felines. 2011
Patricia Gutierrez Gallardo
veterinarian Feline Leukemia Virus (FeLV) is one of the retrovirus of importance in domestic cats (Felis catus) was discovered in 1964 from a domestic cat that had lymphoma, although it is unclear origin, is described that is closely associated with species that are phylogenetically related to the domestic cat. There are two variants of this virus an exogenous, which is usually detected in infected domestic cats, and a variant endogenous, which is presented as provirus inserted in the cells of domestic cats. It is known that endogenous variant has an origin from ancestors of domestic cats which ate a mouse infected with murine leukemia virus, which was able to infect germ cells, and may well perpetuate the species to date. However, this presents no greater risk because they have not been associated pathological changes to their presence, but if there is infection with a variant exogenous recombination can be generated and eventually produce a more lethal disease. Within
related species is the domestic cat and the wildcat (Felis silvestris silvestris), which is the ancestor of the domestic cat. In a study in Scotland, this species has been detected a seroprevalence of 10% by direct ELISA in a population of 50 individuals during the years 1992 and 1997 (Daniels et al, 1999). Additionally in 1996 and 1997 in populations from France, Switzerland and Germany from a total sample of 51 individuals revealed a seroprevalence of 49% (Leutenegger et al, 1999). In turn, we used commercial kits for the detection of FeLV, where the 38 individuals captured in France, he obtained a seroprevalence of 27% (Fromont et al, 2000).
most recent data from a study of Ostrowski et al (2003), which captured 55 individuals of wild cat in Saudi Arabia between 1998 and 2000, where seroprevalence was 3%. Additionally we analyzed other gender-related species Felis in the same region, the sand cat (Felis margarita), which showed that the prevalence of FeLV was 8% of a total of 17 individuals captured.
Another species which has been investigated prevalence of FeLV is the Iberian lynx (Lynx pardinus) where the publication of Luaces et al (2008), sampled in the years 1993 to 2003 obtained 25 samples were analyzed by ELISA kit, which yielded no positive results yet The virus was detected by PCR in 6 of 21 samples, corresponding to 16.7%. One explanation may be that the virus generated in lynx not cross-react with standardized commercial kits for cats not being detected. Additionally, the source of infection may be due to the proximity of human settlement bobcat, and feral domestic cats (Felis catus) and European wild cat (Felis silvestris), which may even share the lynx territories and thus be the focus of infection transmission.
One of the cases recorded in captivity corresponds to a bobcat (Lynx rufus), which reached the Zoological Medicine Service at Colorado State University (USA), with clear nasal mucus FeLV, was confirmed by indirect immunofluorescence direct ELISA, unfortunately the animal did not survive. It was confirmed that the animal was removed after 48 hours of birth, his mother's side and was powered by a domestic cat, which transmitted the infection to a fatal outcome (Sleeman et al, 2001).
In Namibia, conservation foundation cheetah (Cheetah Conservation Fund - CCF) has analyzed over 100 samples for FeLV in cheetahs (Acinonyx jubatus) Namibia wild and no positive animals were detected. However, in one of the cheetahs brought by seizure, there was nasal mucus associated with FeLV, which was confirmed by ELISA, further positive cheetahs were 3, which had some contact with the first cheetah infected, these individuals include infected died of various situations related to infection with FeLV. This is the first confirmed case of FeLV associated with lymphoma in a domestic cat. It is assumed that the source of infection with FeLV exposure had been for a domestic cat cheetah in its previous location at CCF, these data indicate that FeLV is endemic in wildlife populations of cheetahs in Namibia, but the cheetahs are susceptible to infection with FeLV and its consequences (Marker et al, 2003). In a study by Munson et al. (2004), 81 cheetahs sampled between 1992 and 1998 population of Namibia, tested for FeLV antigen by ELISA, there were no antibodies or antigens for FeLV.
The puma (Puma concolor) in Florida are conducted routine testing for FeLV and FIV, in the case of FeLV have been negative since 1978 and 2002, however between 2002 and 2003 there was an outbreak with 28 positive individuals 143 samples for the 19.5%. We conducted a monitoring plan and vaccination against FeLV negative patients younger than 4 months old. With regard to the monitoring plan was established that the 28 individuals, 18 presented a regressive state, 5 were latent and 5 had persistent viremia, of which 2 died from sepsis, 2 and 1 by interspecific aggression by anemia / dehydration. The vaccination plan began in November 2003 to April 2007, where wild cougars FeLV negative 52 received at least one inoculation of these pumas only 26 received a "booster." During vaccination no adverse effects and most of the Cougars developed antibody response. After this outbreak, no positive animals was detected again and allowed to vaccinate, it is believed that infection was not able to replicate in individuals given the number of recessive disease in individuals and not generated latent virus nasal mucus. The source of infection in cougars is unknown, it is speculated that the source of infection was from domestic cats, as consumption of these other FeLV-infected cats may be an effective means of transmission, also found remains of domestic cats the stomachs of necropsied cougars in California and two Florida pumas (Cunningham et al, 2008). Additionally
studies have been conducted in lions (Panthera leo), between 1984 and 1991, 255 individuals were sampled residents of the Serengeti National Park in Tanzania, 51 from the Ngorongoro Crater and Lake Manyara 5 from the analysis by ELISA for p27 antigen of FeLV. The results indicate that the prevalence for FeLV was negative in all samples (Hofmann-Lehmann et al, 1996). In conclusion
infection with the Feline Leukemia Virus is rare in wild species, would only be linked to related species with the domestic cat, as in the case of the wild cat (Felis silvestris silvestris) and the sand cat (Felis margarita .) In other reported cases has been in contact with domestic cats as reported the bobcat, which was nursed by a mother cat, in the case of the cheetah can not be said that there was direct contact, but the possibility is present since it was seized from a human settlement, which probably existed or had pets the presence of feral cats. In the case of cougar has not been reported another outbreak, but is essential to continue monitoring populations and protect habitat for this species, preventing the establishment of urban areas close to populations of cougars. It is important to establish the infective status of the species and that through this we learn that pathogens can dramatically affect population size and take action respect, more so in the case of FeLV and wildlife that this disease has been fatal in all cases reported with persistent viremia. Bibliography
Cunningham M, Brown M, Shindle D, Terrell S, Hayes K, Ferree B, McBride R, Blankenship E, Jansen D, Cittinus S, Roelke M, Kiltie R, Troyer J and O'Brien S (2008 .) Epizootiology and management of feline leukemia virus in the Florida puma. Journal of wildlife disease 44 (3), 2008, pp.537-552.
Daniels M, Golder M, Jarrett O and MacDonald D (1999). Feline Viruses in Wildcats from Scotland. Journal of Wildlife Diseases, 35 (1), 1999, pp. 121-124
Fromont E, Sager A, Leger F, Bourguemestre F, Jouquelet E, Stahl R, Pontier D and Artois M (2000). Prevalence and pathogenicity of retroviruses in wildcats in France. Veterinary Record (2000). 146, pp.317-319
Hofmann-Lehmann R, Fehr D, Grob M, Elgizoli M, Packer C, Martenson J, O´Brien S and Lutz H (1996). Prevalence of antibodies to feline parvovirus, calicivirus, herpesvirus, coronavirus, and immunodeficiency virus and of feline leukemia virus antigen and the interrelationship of these viral infections in free-ranging lions in east Africa. Clinical and Diagnostic Laboratory immunology, sept. 1996. Vol. 3, N°5 p. 554-562
Leutenegger C, Hofmann-Lehmann R, Riols C, Liberek M, Worel G, Lups P, Fehr D, Hartmann M, Weilenmann P and Lutz H (1999). Viral infections in free-living populations of the European wildcat. Journal of wildlife disease, 35 (4), 1999, pp. 678-686
Luaces I, Doménech A, García-Montijano M, Collado V, Sánchez C, Tejerizo G, Galka M, Fernández P and Gómez-Lucía E (2008). Detection of Feline leukemia virus in the endangered Iberian lynx (Lynx pardinus). J Vet Diagn Invest 20:381–385 (2008).
Marker L, Munson L, Basson P and Quackenbush S (2003). Multicentric T-cell Lymphoma Associated with Feline Leukemia Virus infection in a Captive Namibian Cheetah (Acinonyx jubatus). Journal of Wildlife Diseases, 39(3), 2003, VOL. 39, NO. 3, pp. 690–695.
Munson L, Marker L, Dubovi E, Spencer J, Evermann J and O’Brien S (2004). Serosurvey of viral infections in free-ranging Namibian Cheetas. Journal of Wildlife Diseases, 40(1), 2004, pp. 23–31
Ostrowski S, Van Vuuren M, Lenair D and Durand A (2003). A serologic survey of wild felids from central west Saudi Arabia. Journal ofnwlidlife disease, 39(3), 2003, pp. 696-701
Sleeman J, Keane J, Johnson J, Brown R and VandeWoude S (2001). Feline Leukemia Virus in a Captive Bobcat. Journal of Wildlife Diseases, 37(1), 2001, VOL. 37, NO. 1, January 2001. pp. 194–200.
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