MOLECULAR DIAGNOSIS OF FELINE LEUKEMIA VIRUS BY PCR IN FELINES TREATED AT A VETERINARY CLINIC
Abstract
Feline leukemia virus (FeLV) is a gammaretrovirus that can cause immunosuppression, anemia, and neoplasia in cats, with substantial morbidity and mortality. Because infected cats can remain asymptomatic and still transmit the virus, early identification and preventive management depend on reliable diagnostic testing. This study aimed to estimate the prevalence of FeLV infection detected by polymerase chain reaction (PCR) and to explore potential epidemiological risk factors in domestic cats treated at a veterinary clinic (blinded for review) in Brazil. Blood samples were collected from clinically healthy cats and submitted to PCR for FeLV proviral DNA detection. Demographic and epidemiological variables (age, sex, neuter status, street access, rescue history, and contact with FeLV-positive cats) were recorded. Bivariate analyses were performed using odds ratios (OR) and Fisher’s exact test when appropriate (p<0.05). Seven of 72 cats (9.7%) were PCR-positive. Most positive cats were male (4/7; 57%) and belonged to the junior age group (7–24 months). All PCR-positive cats had street access and were rescued. Street access was the only variable associated with PCR positivity (Fisher’s exact test, p=0.012). These findings reinforce the value of PCR for FeLV screening and support preventive strategies such as routine testing, isolation of positive animals, vaccination of negatives, and restriction of outdoor access.
Author Biographies
Médica-veterinária. Atua na área de Inspeção de Alimentos e Controle físico-químico de produtos de origem animal. Afya UNIGRANRIO, Duque de Caxias, Rio de Janeiro, Brasil.
Zootecnista. Docente e pesquisadora na área de genética e melhoramento animal, com interesse em bioestatística. Afya UNIGRANRIO, Duque de Caxias, Rio de Janeiro, Brasil.
Atua como pesquisadora na área de genética molecular com ênfase no estudo de doenças crônicas-degenerativas. Afya UNIGRANRIO, Duque de Caxias, Rio de Janeiro, Brasil.
Atua como pesquisadora na área de biologia molecular e celular, genética humana. Afya UNIGRANRIO, Duque de Caxias, Rio de Janeiro, Brasil.
Zootecnista e Médico-veterinário. Docente e pesquisador na área de clínica médica de pequenos animais e diagnóstico, com atuação em cardiologia e pneumologia veterinária. Universidade de Vassouras, Vassouras, Rio de Janeiro, Brasil.
Médica-veterinária. Docente e pesquisadora com interesse em bioquímica e patologia. Afya UNIGRANRIO, Duque de Caxias, Rio de Janeiro, Brasil.
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