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This study aimed to evaluate in vivo the use of the extract from the leaves of Melia azedarach in the ethyl acetate fraction at a concentration of 150 µg/mL as an antiretroviral treatment against small ruminant lentiviruses (SRLV) in goat colostrum, and milk with a 90-min action. Two groups of six kids were treated with the extract. One group received three supplies of colostrum from does naturally positive for SRLV, treated with the ethyl acetate fraction of M. azedarach (EAF-MA) for three days, while the other group consumed milk from does also carrying the virus with the respective extract twice a day for five days. After undergoing treatment, all animals began to receive thermized milk until weaning (60 days) and were monitored for six months using nested polymerase chain reaction (nPCR) and western blot (WB) tests. The study revealed cumulative percentages of positive animals in WB or nPCR in the milk group of 66.66% on the seventh day, 83.33% in the following week, and 100% at 120 days, while the colostrum group showed values of 66.66% at 14 days, 83.33% at 90 days, and 100% at 120 days. Variation and intermittency were observed in viral detection, but all animals tested positive in WB or nPCR at some point. A potential delay in infection was observed, which was more significant in the colostrum group. The need for the combination of serological and molecular tests for a more efficient detection of the disease is also emphasized.

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The objective of this study was to analyze the immune responses of bucks to small ruminant lentivirus (SRLV) with a focus on the reproductive system of males with recent and chronic infection. A total of 12 bucks were selected, six seronegative and six seropositive with chronic natural infection for more than 18 months (chronic infection group). After selecting the animals, the six seronegative males were intravenously inoculated with caprine arthritis-encephalitis virus (CAEV)-Co viral strain at a titer of 10-5,6 TCID50/mL. After viral inoculation, this group was called the recent infection group and was monitored weekly with the chronically infected group for 180 days with blood serum and seminal plasma Western Blot (WB) analysis. Of the animals with chronic SRLV infection, 18.94% (50/264) showed anti-SRLV antibodies in at least one of the samples, and 81.06% (214/264) were negative. Anti-SRLV antibodies were detected in 27.27% (36/132) of the blood serum samples from this group, while 10.60% (14/132) were reactive in the seminal plasma WB test. The animals inoculated with CAEV-Co became seropositive after the third week of viral inoculation. In this group, 31.06% (41/132) of seminal plasma samples had anti-SRLV antibodies, and of these, 70.73% (29/41) coincided with blood serum results. Of the remaining 29.27% (12/41), the seminal plasma sample of only three animals (RIA2, RIA3, and RIA5) had anti-SRLV antibodies. One of the animals with a recent infection presented anti-SRLV antibodies only in seminal plasma samples, possibly due to virus compartmentalization. Intermittent viral shedding was observed in both biological samples, regardless of the infection stage. The immune response in bucks with recent SRLV infection is more significant than in chronically infected animals. Regardless of the stage of infection, there is a fluctuation in antibody levels, therefore, this creates a risk of false-negative samples when performing the diagnosis.

O objetivo desse estudo foi analisar a resposta imunológica aos lentivírus de pequenos ruminantes (LVPR) com enfoque no sistema reprodutor de machos com infecção recente e crônica. Para isso, foram selecionados 12 reprodutores caprinos, sendo seis soronegativos e seis soropositivos com infecção natural crônica há mais de 18 meses (grupo com infecção crônica). Após seleção dos animais, os seis machos soronegativos foram inoculados com a cepa viral do vírus da artrite encefalite caprina (CAEV)-Co, título 10-5,6 TCID50/mL, por via intravenosa. A partir da inoculação viral este agrupamento passou a ser denominado de grupo com infecção recente e juntamente com o grupo com infecção crônica foram acompanhados, semanalmente por 180 dias, com análise dos testes de Western Blot (WB) no soro sanguíneo e plasma seminal. Nos animais com infecção crônica para LVPR, 18,94% (50/264) apresentaram anticorpos anti-LVPR em pelo menos uma das distintas amostras, e 81,06% (214/264) tiveram resultados negativos. Das amostras de soro sanguíneo do referido grupo, em 27,27% (36/132) detectou-se anticorpos anti-LVPR, enquanto que no plasma seminal 10,60% (14/132) foram reagentes no teste de WB. Nos animais inoculados com o CAEV-Co, ocorreu a soroconversão após a terceira semana da inoculação viral. Nesse grupo, 31,06% (41/132) das amostras de plasma seminal tiveram anticorpos anti-LVPR, sendo que dessas 41, 70,73% (29/41) coincidiram com resultado das amostras de soro sanguíneo. Nos 29,27% (12/41) restante, houve a detecção somente no plasma seminal e eram amostras provenientes de três animais (AIR2, AIR3 e AIR5). Em um dos animais com infecção recente, só foi identificado anticorpos anti-LVPR em amostras de plasma seminal, possivelmente em função da compartimentalização do vírus. Intermitência viral foi observada em ambas as amostras biológicas, independentemente do estágio de infecção. Conclui-se que a resposta imunológica em reprodutores com infecção recente LVPR é mais acentuada do que em animais cronicamente infectados. E, independentemente do estágio da infecção há uma flutuação nos níveis de anticorpos, sendo, portanto, um fator de risco, em virtude da existência de amostras falso-negativo ao realizar o diagnóstico.

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Goat farming is of great importance for agriculture in Northeast of Brazil, which owns more than 90 % of the national herd, however, most studies on leptospirosis in goats in this region are local surveys with unplanned sampling. Thus, the objective of this study was to determine the factors associated with the seroprevalence of leptospirosis in goats in Northeast region of Brazil. Blood samples were collected from 4121 goats from 222 herds, belonging to the states of Ceará, Paraíba, Piauí , Rio Grande do Norte and Sergipe. Serological diagnosis was carried out using the microscopic agglutination test (MAT). In 82.9 % (95 % CI = 77.3-87.2 %) of the herds there was at least one animal seropositive for at least one of the serogroups of Leptospira sp., and 18.73 % (95 % CI = 17.5-19.9 %) of the animals were seropositive. Antibody titers ranged from 100 to 800 and the most frequent serogroups were Autumnalis (23.06 %) and Australis (20.98 %). According to the robust Poisson regression analysis, four factors were associated with seroprevalence: animal sex (female) (P = 0.040), educational level of the farmer (elementary school) (P < 0.001), contacting institution for technical support (P = 0.040) and presence of irrigation area (P = 0.002). There was a high frequency of Leptospira sp. in goats in the states of Northeast region of Brazil, and it's suggested the need for better technological and preventive assistance of herds.

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Background: Chlamydia abortus infections (Chlamydiosis) can cause reproductive problems in sheep, such as abortionsand birth defects, leading to farm productivity loss. The symptoms, which are similar to other reproductive diseases, andthe microbial pathogenesis make the clinical diagnosis difficult. Chlamydia abortus is a zoonotic pathogen, making it apublic health issue because it can infect and induce abortions in humans. This study investigated anti-C. abortus antibodylevels and infection risk factors in sheep in the State of Ceará, Brazil.Materials, Methods & Results: Forty-three properties from 10 municipalities in 4 mesoregions in the State of Ceará, Brazil(Sertões, metropolitan Fortaleza, North Ceará and Northwest Ceará) with sheep, goats, cattle, and horses were visited.Five hundred and four serological samples from sheep were collected and tested for anti-C. abortus antibodies using anEnzyme-linked Immunosorbent Assay (ELISA) [IDEXX®, Australia] and all procedures were performed in accordancewith the manufacturers instructions at the Clinical Pathology Laboratory of EMBRAPA Goats and Sheep (Sobral, Brazil). Individual questionnaires were completed about sheep breeding practices and to identify possible C. abortus risks.Seropositive results were found in 18.45 % (93/504 individuals) of sheep, and 88.37 % (38/43 properties) of the herds hadat least one seropositive animal. The number of seropositive individuals was significantly different between adults andewes [P < 0.01; Odds Ratio (OR) = 0.510; 95% confidence interval (CI) = 0.306 - 0.850]. Logistic regression modelingidentified a missing health certificate request for newly acquired animals as a chlamydiosis risk factor [P = 0.038; OR =2.672; 95% CI = 1.058 - 6.749].Discussion: The prevalence of anti-C. abortus...(AU)

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Background: Small ruminant lentivirus (SRLV) belong to genus Lentivirus, family Retroviridae. These viruses causecaprine arthritis encephalitis (CAE) and maedi visna (MV), infectious diseases that cause economic, production, and reproductive losses. There are no effective treatments or vaccines for these diseases. Thus, early detection via serology hasgreat importance for control of SRLV. Therefore, the objective of this review is to demonstrate the potential of the westernblot (WB) test as an immunodiagnostic test for SRLV.Review: In general, immunodiagnosis of SRLV is performed via agar gel immunodiffusion (AGID) and indirect enzymelinked immunosorbent assay (ELISA), which can detect antibodies in several different biological samples but is used preferably with serum and blood plasma. However, WB has demonstrated efficacy in the early diagnosis of immunoglobulinsagainst SRLV, presenting higher sensitivity and specificity than the serological tests usually used, because this techniquecan detect antibodies at a dilution as much as 256 times greater than that of AGID and 32 times greater than that of ELISA.SRLV infection and consequent immunological activation result in the induction of cellular and humoral responses. Additionally, around the third week, production of antibodies directed mainly toward viral capsid proteins (p25 and p28)occurs. After the fifth week, production of immunoglobulins directed toward other viral proteins occurs. Because of thepersistence of SRLV infection, serology is considered to be the most practical means to diagnosis. Each serological testhas a percentage specificity and distinct sensitivity, as well as advantages and disadvantages in its applicability. It shouldbe noted that there is no gold standard test for diagnosis of SRLV infection. Moreover, SRLV are characterized by escapemechanisms such as genetic diversity, mutagenic potential, viral intermittence...(AU)

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Considering the importance of leptospirosis in sheep farming and public health and the significance of identifying which serogroups circulate in sheep within each region, the objective of this study was to determine the seroprevalence and spatial distribution of the most frequent serogroups causing infection by Leptospira sp. in ovine herds in the Northeast region of Brazil. Blood samples were collected from 4197 sheep from 229 herds in 7 Northeastern States. Sera were analyzed via microscopic agglutination test (MAT). The frequency of seroreactive sheep for Leptospira sp. was 14.06%. The states of Alagoas, Ceará, Paraíba, Piauí, Rio Grande do Norte, and Sergipe, located in the Caatinga biome, had the highest frequencies of serologically reactive sheep, and Maranhão, in the Cerrado biome, had the lowest frequency. The most frequent serogroups were Autumnalis (19.49%), Australis (15.76%) and Serjoe (14.41%). In the states of Ceará, Paraíba, Rio Grande do Norte, and Sergipe, 100% of their municipalities had at least one seroreactive animal. The highest frequencies of seropositive animals were found in the municipalities of União (50%), Passagem (49.06%), Canindé (48.89%), Igaci (28.95%), Gararu (31.2%), Pirapemas (17.5%), and Angicos (16%) located in the states of Piauí, Paraíba, Ceará, Alagoas, Sergipe, Maranhão and Rio Grande do Norte, respectively. The animal-level prevalence (14.06%) obtained in the present study is significant, especially considering the rustic nature of the species and the adverse conditions of the region for the infectious agent. In semi-arid conditions, it has been suggested that perhaps sheep do not seroconvert detectable titers on MAT with a cut-off point of 1:100. It is important to highlight that the ovine population in the Northeast region of Brazil is composed of mixed animals, which have been considered more resistant to infection by Leptospira spp. Also, environmental factors hostile to the survival of the infectious agent in the studied region should be taken into consideration, since they may have influenced the seropositive animal-level prevalence. A noteworthy variation was observed in agglutinin titers, which ranged from 100 to 1,600, where 80.2% of the positive samples had titers ≤ 200. It is important to highlight that more elevated titers (≥ 400) were obtained in all seven states, which may suggest an acute infection caused by a non-adapted serovar, indicating that preventive and control measures focused on possible infection sources for sheep should be adopted. Although some states showed the same serogroups as the most frequent, a variety of serogroups was observed in municipalities, which may indicate different sources of infection, whether interspecies, intraspecies, or via alternative routes of transmission in semi-arid conditions, such as venereal. This indicates that even though sheep are more resistant to infection, they become exposed due to the environment or management conditions. As such, identification, isolation, and treatment of the affected animals are alternative measures recommended for prevention and control of leptospirosis in sheep in the semi-arid region. It is evident that despite the lack of rain observed in the last decade in the Northeast region of Brazil, which prevented the formation of favorable environments for the presence of Leptospira, the infectious agent remains among the sheep, as well as other production and wild animals in the region. Some factors may be contributing to this scenario, such as the fact that sheep farming in the region is = characterized mainly by subsistence systems, where veterinary assistance and adequate sanitary management are absent, thus increasing the possibility of contact with Leptospira. (AU)

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Background: Small ruminant lentivirus (SRLV) belong to genus Lentivirus, family Retroviridae. These viruses causecaprine arthritis encephalitis (CAE) and maedi visna (MV), infectious diseases that cause economic, production, and reproductive losses. There are no effective treatments or vaccines for these diseases. Thus, early detection via serology hasgreat importance for control of SRLV. Therefore, the objective of this review is to demonstrate the potential of the westernblot (WB) test as an immunodiagnostic test for SRLV.Review: In general, immunodiagnosis of SRLV is performed via agar gel immunodiffusion (AGID) and indirect enzymelinked immunosorbent assay (ELISA), which can detect antibodies in several different biological samples but is used preferably with serum and blood plasma. However, WB has demonstrated efficacy in the early diagnosis of immunoglobulinsagainst SRLV, presenting higher sensitivity and specificity than the serological tests usually used, because this techniquecan detect antibodies at a dilution as much as 256 times greater than that of AGID and 32 times greater than that of ELISA.SRLV infection and consequent immunological activation result in the induction of cellular and humoral responses. Additionally, around the third week, production of antibodies directed mainly toward viral capsid proteins (p25 and p28)occurs. After the fifth week, production of immunoglobulins directed toward other viral proteins occurs. Because of thepersistence of SRLV infection, serology is considered to be the most practical means to diagnosis. Each serological testhas a percentage specificity and distinct sensitivity, as well as advantages and disadvantages in its applicability. It shouldbe noted that there is no gold standard test for diagnosis of SRLV infection. Moreover, SRLV are characterized by escapemechanisms such as genetic diversity, mutagenic potential, viral intermittence...

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Background: Chlamydia abortus infections (Chlamydiosis) can cause reproductive problems in sheep, such as abortionsand birth defects, leading to farm productivity loss. The symptoms, which are similar to other reproductive diseases, andthe microbial pathogenesis make the clinical diagnosis difficult. Chlamydia abortus is a zoonotic pathogen, making it apublic health issue because it can infect and induce abortions in humans. This study investigated anti-C. abortus antibodylevels and infection risk factors in sheep in the State of Ceará, Brazil.Materials, Methods & Results: Forty-three properties from 10 municipalities in 4 mesoregions in the State of Ceará, Brazil(Sertões, metropolitan Fortaleza, North Ceará and Northwest Ceará) with sheep, goats, cattle, and horses were visited.Five hundred and four serological samples from sheep were collected and tested for anti-C. abortus antibodies using anEnzyme-linked Immunosorbent Assay (ELISA) [IDEXX®, Australia] and all procedures were performed in accordancewith the manufacturer’s instructions at the Clinical Pathology Laboratory of EMBRAPA Goats and Sheep (Sobral, Brazil). Individual questionnaires were completed about sheep breeding practices and to identify possible C. abortus risks.Seropositive results were found in 18.45 % (93/504 individuals) of sheep, and 88.37 % (38/43 properties) of the herds hadat least one seropositive animal. The number of seropositive individuals was significantly different between adults andewes [P < 0.01; Odds Ratio (OR) = 0.510; 95% confidence interval (CI) = 0.306 - 0.850]. Logistic regression modelingidentified a missing health certificate request for newly acquired animals as a chlamydiosis risk factor [P = 0.038; OR =2.672; 95% CI = 1.058 - 6.749].Discussion: The prevalence of anti-C. abortus...

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Caseous lymphadenitis (CLA) caused by the pathogenic bacterium, Corynebacterium pseudotuberculosis, results in economic loss in goat farming. Its prevalence in Brazilian herds varies from 5 to 50%, generating expenses with treatment, loss in production, carcass and organ condemnation, and reduced price of the hide. This study aimed to describe the distribution of lesions and quantify the loss associated with CLA in goat breeding due to condemnation in a slaughterhouse located in a semiarid region. The study was conducted at the municipal slaughterhouse of the city of Patos, State of Paraíba, Northeastern Brazil, where goats from this intermediate geographical region are slaughtered. In 2017, 3,662 animals were slaughtered, an average of 305 per month. During the study period, from March to August 2017, 304 goats of both sexes and different ages of undefined breed were assessed. In the ante-mortem examination, inspection and palpation of the superficial lymph nodes was done; in the post-mortem examination, organ and viscera were assessed. The caseous material collected was sent for microbiological analysis. Of the 304 individuals, 227 [74.67% (95% CI: 69.50-79.23)] did not have any lesions, while 77 [25.33% (95% CI: 20.77-30.50)] showed abscesses suggestive of CLA, which was confirmed in 65 goats [84.41% (95% CI: 76.30-92.50)]. Sex (P = 0.044) and age (P = 0.002) were associated with infection. While the sex of the animals affected carcass and viscera weights and carcass yield, their age affected live weight, carcass, organ, and viscera weights; conversely, the incidence of CLA did not affect these variables. The average price in Real (R$) of a kilogram (kg) of goat meat cuts and “offal” was used to calculate the economic loss. Considering the average carcass weight (11,485 kg), organ weight (1,085 kg), and viscera weight (2,013 kg), 4,433.232 kg of meat was produced, resulting in R$ 72,945.43. The condemnations resulted in the loss of 269.894 kg, which is equivalent to R$ 4,540.33. CLA is responsible for a negative impact of 6.09% on production. Implementing control measures for this disease is important to increase the financial return in goat farming.(AU)

Linfadenite Caseosa (LC) causada pela bactéria patogênica Corynebacterium pseudotuberculosis resulta em perda econômica na caprinocultura. No rebanho brasileiro sua prevalência varia de 5 a 50%, gerando gastos com tratamento, queda de produção, condenação de carcaça e órgãos, e desvalorização da pele. O objetivo deste trabalho foi quantificar a perda associada à LC na caprinocultura de corte por condenação em abatedouro do semiárido, bem como caracterizar a distribuição das lesões. O trabalho foi realizado no Abatedouro Municipal da cidade de Patos, Estado da Paraíba, Nordeste do Brasil, onde ocorre abate de caprinos provenientes desta região geográfica intermediária. No ano de 2017 foram abatidos 3.662 animais, uma média de 305 por mês. Durante o período de estudo, março a agosto do mesmo ano, avaliou-se 304 caprinos sem padrão racial definido, ambos os sexos e idades diversas. No exame ante mortem foram submetidos à inspeção e palpação de linfonodos superficiais; post mortem, órgãos e vísceras. O material caseoso coletado foi submetido à análise microbiológica para diagnóstico. Dos 304 indivíduos, 227 [74,67% (IC 95%: 69,50-79,23)] não apresentaram qualquer lesão, enquanto 77 [25,33% (IC 95%: 20,77-30,50)] evidenciaram abscessos sugestivos de LC, com confirmação em 65 [84,41% (IC 95%: 76,30-92,50)]. Constatou-se associação de sexo (P = 0,044) e idade (P = 0,002) à infecção. Foi verificado efeito do sexo dos animais nas variáveis peso de carcaça, peso de vísceras e rendimento de carcaça, bem como houve efeito da idade nas variáveis peso vivo, peso de carcaça, peso de órgãos e peso de vísceras; no entanto, não houve efeito da ocorrência de LC nessas variáveis. Para cálculo de perda econômica adotou-se o preço médio em Real (R$) do quilograma (kg) dos cortes de carne caprina, e “miúdos”. Considerando o peso médio de carcaça (11,485 kg), órgãos (1,085 kg) e vísceras (2,013 kg), houve produção de 4.433,232 kg, resultando em R$ 72.945,43. As condenações subtraíram 269,894 kg, equivalente a R$ 4.540,33. Atribui-se à LC um impacto negativo de 6,09% na produção. Implementar medidas de controle para essa doença é importante para que se amplie o retorno financeiro à atividade.(AU)

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This study aimed to evaluate by means of Nested Polymerase Chain Reaction (nPCR), co-cultivation and sequencing, with genetic comparison between strains (mother/newborn), the occurrence of vertical transmission of Small Ruminant Lentiviruses (SRLV) from naturally occurring nannies infected for their offspring. For the detection of SRLV seropositive progenitors, blood was collected from 42 nannies in the final third of gestation in tubes with and without anticoagulant. The diagnostic tests used were Western Blot (WB) and nPCR. During the period of birth, the same blood collection procedure was performed on 73 newborns at zero hours of birth, with the same diagnostic tests. Seventeen blood samples from seven-day-old kids, proven positive for SRLV by nPCR, chosen at random, were subjected to coculture in goat synovial membrane (GSM) cells for 105 days. The pro-viral DNA extracted from the cell supernatant from the coculture was subjected to nPCR. For DNA sequencing from the nPCR products, nine positive samples were chosen at random, four nannies with their respective offspring, also positive. Each sample was performed in triplicate, thus generating 27 nPCR products of which only 19 were suitable for analysis. Among the 42 pregnant goats, in 50% (21/42) pro-viral DNA was detected by nPCR, while in the WB, only 7.14% (3/42) presented antibodies against SRLV. Regarding neonates, of the 73 kids, 34 (46.57%) were positive for the virus, using the nPCR technique, while in the serological test (WB), three positive animals (4.10%) were observed. The coculture of the 17 samples with a positive result in the nPCR was confirmed in viral isolation by amplification of the SRLV pro-viral DNA. When aligned, the pro-viral DNA sequences (nannies and their respective offspring) presented homology in relation to the standard strain CAEV Co. It was concluded that the transmission of SRLV through intrauterine route was potentially the source of infection in the newborn goats.

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