This study was conducted in order to evaluate the transmission of caprine lentivirus to sheep using different experimental groups. The first one (colostrum group) was formed by nine lambs receiving colostrum from goats positive for small ruminant lentiviruses (SRLV). The second group (milk group) was established by nine lambs that received milk of these goats. Third was a control group, consisting of lambs that suckled colostrum and milk of negative mothers. Another experimental group (contact group) was formed by eight adult sheep, confined with two naturally infected goats. The groups were monitored by immunoblotting (IB), enzyme-linked immunosorbent assay (ELISA), agar gel immunodiffusion (AGID) and nested polymerase chain reaction (nPCR). All lambs that suckled colostrum and milk of infected goats and six sheep of the contact group had positive results in the nPCR, although seroconversion was detected only in three of the exposed animals, with no clinical lentiviruses manifestation, in 720 days of observation. There was a close relationship between viral sequences obtained from infected animals and the prototype CAEV-Cork. Thus, it was concluded that SRLV can be transmitted from goats to sheep, however, the degree of adaptation of the virus strain to the host species probably interferes with the infection persistence and seroconversion rate.

No abstract

Resumo -O objetivo deste trabalho foi avaliar a presença do DNA pró-viral do lentivírus caprino (LVC) em ejaculados de machos infectados naturalmente, e verificar a influência da lavagem do sêmen e da presença de inflamação testicular sobre a carga viral. Foram realizadas oito coletas de sêmen de sete reprodutores soropositivos para o LVC: quatro antes dos animais sofrerem dano testicular e quatro depois. Entre as coletas realizadas na mesma semana, em uma, o ejaculado era lavado, para retirada do plasma seminal, e na outra, não. O DNA pró-viral do LVC foi identificado pela reação em cadeia da polimerase Nested (PCR Nested), e pelo isolamento viral. O vírus foi isolado em 7,1% das amostras. A PCR identificou o DNA pró-viral em 35,7% do total das amostras: 17,9% nas amostras lavadas e 53,6% das amostras de sêmen integrais. O dano ao testículo permite maior fluxo do vírus para o sêmen, pois antes do dano, 21,4% das amostras foram positivas e pós-dano, 50%. A transmissão do LVC pelo sêmen de reprodutores caprinos é potencializada pela presença de inflamações testiculares e pelo fato de o sêmen criopreservado conter o LVC na forma infectante.Termos para indexação: reprodução, PCR, artrite-encefalite caprina, transmissão. Risk factors in caprine lentivirus transmission through semenAbstract -The objective of this work was to evaluate the presence of the DNA provirus of the caprine lentivirus (LVC) in ejaculates of naturally infected males, and to verify the influence of the wash of the semen as well as the presence of testicle inflammation on the viral load. Eight semen collections of seven soropositive reproducers were accomplished, four before testicle injury and four after injury. Amongst the collections carried out at the same week, in one the ejaculate was washed, to withdraw the plasma seminal, and in the other it was not. The provirus DNA was identified both by Nested polymerase chain reaction technique (Nested PCR) and by the viral isolation. The virus was isolated in 7.1% of the samples. The PCR identified the provirus DNA in 35.7% of all samples, 17.9% in the washed samples and 53.6% of the integral semen samples. The injury of the testicle tends to greater flow of virus for the semen, therefore, before injury, 21.4% of the samples were positive and after-injury, 50%. Risk of transmission of the LVC by semen of goat reproducers is strengthened by the presence of testicle inflammations and the fact that the criopreserved semen contains the LVC in infecting form.Index terms: reproduction, PCR, caprine arthritis encephalitis, transmission. IntroduçãoO lentivírus caprino (LVC) é o agente etiológico da artrite-encefalite caprina (AEC), uma enfermidade crônica, incurável, de alta prevalência em rebanhos leiteiros nacionais e associada à perdas econômicas. Há grande necessidade de pesquisa dos modos de transmissão desse vírus para o delineamento eficiente de medidas de controle e possível erradicação.O avanço das técnicas de conservação de germoplasma, aliado ao aumento da importância econômica da caprinocultura, ...

No abstract

A introdução de novas raças, com o objetivo de aumentar a produtividade, levou à alteração do perfil sanitário dos rebanhos. Dentre as enfermidades introduzidas no Brasil, destacam-se as lentiviroses de pequenos ruminantes (LVPR), representadas pela artrite-encefalite caprina (CAE) e pela maedi-visna (MV). Devido à importância econômica da ovinocultura para a microrregião de Juazeiro-Bahia e à escassez de dados sobre a lentivirose em ovinos, buscou-se obter a prevalência da MV. Foram avaliados 919 soros por imunodifusão em gel de ágar (IDGA). As amostras foram colhidas nos oito municípios que compõem essa microrregião (Juazeiro,

Este trabalho teve como finalidade verificar a prevalência sorológica da lentivirose caprina (LVC) na microrregião de Juazeiro, na Bahia, por meio da técnica de imunodifusão em gel de agar (IDGA), bem como caracterizar os sistemas de criação da região. Para tal, foram avaliadas 693 amostras de soros sanguíneos de caprinos de 46 propriedades rurais em diferentes localidades, pertencentes aos 8 municípios formadores da microrregião (Campo Alegre de Lourdes, Casa Nova, Curaçá, Juazeiro, Pilão Arcado, Remanso, Sento Sé e Sobradinho). Na realização das visitas, aplicou-se um questionário com ênfase nas informações referentes ao manejo sanitário. Das propriedades visitadas, todas apresentavam sistema de criação extensivo, com predomínio de animais sem raça definida, baixa produtividade e baixo índice de tecnificação, visando principalmente à obtenção de carne. As principais enfermidades relatadas foram linfadenite caseosa, diarreias, ectoparasitoses e ceratoconjuntivite. Quanto à soroprevalência, 0,29% (2/693) das amostras apresentaram sorologia positiva para a LVC. Os animais positivos pertenciam à mesma propriedade, no município de Curaçá, que apresentou 12,5% (1/8) de propriedades positivas, contrastando com 2,17% (1/46) de soroprevalência total dos rebanhos visitados. Estes resultados sugerem, portanto, a necessidade da efetivação de medidas preventivas na região, principalmente no momento em que se verifica a importação de animais para melhoramento genético.

Caprine arthritis-encephalitis (CAE) is aninfectious disease caused by the caprine arthritis-encephalitis virus (CAEV), belonging to the lentivirus genus. The presence of the virus has been observed in the nervous system, respiratory tract and mammary gland, and also in the male and female genital tract. The objective of this study is to identify the virus in oocyte and uterine fluid of infected goats by molecular diagnostic techniques, in order to assess the possibility of CAEV transmission with reproduction. Thirteen infected goats were selected and submitted to euthanasia for the collection of the reproductive system, aspiration of the uterine fluid and dissection of ovaries for oocyte collection. In order to identify the CAEV in the collected material, in the protovirus and free forms, it was submitted to the nRT-PCR and nPCR techniques, respectively. As a result, it was observed that 53.8% of oocytes were positive to nRT-PCR, while only 9.1% were positive to nPCR. The nRT-PCR also identified the virus in the uterine fluid of 46.1% of the tested females. Even though the 13 goats had CAEV, 30.8% presented negative results in nPCR and nRT-PCR in all of the analyzed samples (oocyte and uterine fluid). This work concludes that nRT-PCR and nPCR can be used in the diagnosis of CAE for the analysis with oocytes and uterine fluid, and that the presence of CAEV in these materials points out to the risk of CAEV transmission through reproductive technologies used in females.

Small Ruminant Lentiviruses (SRLV) are infectious diseases of viral etiology caused by retroviruses, characterized for being a slowly progressive degenerative disease. The aim of this study was to determine the occurrence of antibodies against lentivirus in the flock of Santa Inês sheep in Sergipe, Brazil. A minimum number of samples was analyzed by the Astudillo calculation, with an expected prevalence (p) of 10%, error rate (α) of 20% and confidence level of 95% (g = 1.96) obtaining the minimum number of samples (n) of 861. Finally, 941 serum samples were collected, derived from 54 properties and 19 municipalities distributed in three regions of the State, and the number of collected samples was proportional to the sheep flock of each municipality. The serum was placed at -20°C until the Agar Gel Immunodiffusion test (AGID), and results considered as positive or suspicious in AGID were assessed by the Western blotting technique. Out of sampled animals, 194 (20.62%) were male and 747 (79.38%) were female. From the stratification by age, 300 were young sheep (31.88%), aged between six months and one year old, 308 (32.73%) were young adults, aged between 1 and 3 years old, and 333 (35.39%) were estimated to be older than three years old. Results showed that antibodies against the Maedi-Visna virus in the sheep flock occurred in the State of Sergipe at low frequency (0.11%). Thus, the occurrence of Maedi-Visna infection in sheep in the State of Sergipe is reported, and emphasizes the participation of the transit of animals in the epidemiology of the disease. trados, 194 (20,62%) eram machos e 747 (79,38%) eram fêmeas. Quanto à estratificação por idade, 300 ovinos eram jovens (31,88%), entre seis meses e um ano, 308 (32,73%) eram jovens adultos, entre 1 e 3 anos, e 333 (35,39%) tinham idade estimada superior a 3 anos. Os resultados obtidos demonstraram que anticorpos contra o vírus Maedi-Visna (MVV) ocorrem no rebanho ovino do estado de Sergipe em baixa frequência (0,11%). Assim, relata-se a ocorrência da infecção por Maedi-Visna em ovinos no estado de Sergipe e ressalta--se a participação do trânsito de animais na epidemiologia da doença. KEYWORDS