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Background: Chlamydia abortus infections (Chlamydiosis) can cause reproductive problems in sheep, such as abortions and birth defects, leading to farm productivity loss. The symptoms, which are similar to other reproductive diseases, and the microbial pathogenesis make the clinical diagnosis difficult. Chlamydia abortus is a zoonotic pathogen, making it a public health issue because it can infect and induce abortions in humans. This study investigated anti-C. abortus antibody levels 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 an Enzyme-linked Immunosorbent Assay (ELISA) [IDEXX®, Australia] and all procedures were performed in accordance with 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 had at least one seropositive animal. The number of seropositive individuals was significantly different between adults and ewes [P < 0.01; Odds Ratio (OR) = 0.510; 95% confidence interval (CI) = 0.306 - 0.850]. Logistic regression modeling identified 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 antibodies in sheep in the State of Ceara emphasizes the importance of testing and tracking the disease spread among herds; these results were similar to studies in other areas of Brazil. Adult sheep that spend more time on the property may have a higher exposure risk because of increased reproductive activity. Misinformation and technical limitations can influence the proper handling of animals avoiding contagion through the correct use of techniques and recommendations. Disease transmission occurs through the digestive tract and between mother and fetus. Therefore, seropositive (infected) sheep may be related to the breeding system practices, such as allowing contact between sheep and other species on the property (goats, cattle, and horses) during breeding. Acquiring animals from external sources without sufficient health information can increase the transmission risk. Contaminated pastures, water, food, and air also increase transmission risk. The lack of technical and practical knowledge regarding disease prevention and control also contributes to disease transmission, resulting in reproductive losses due to high abortion rates. Chlamydia abortus has zoonotic potential and may infect humans without proper safety information. Therefore, future epidemiological studies are required for a better understanding of the primary risk factors for disease occurrence and spread among herds in the region. Chlamydia abortus infection is present in sheep in Ceará, Brazil. Chlamydiosis information programs should be adopted, sanitary measures implemented, and the epidemiological surveillance of sheep herds strengthened. Made available in DSpace on 2021-12-10T12:05:08Z (GMT). No. of bitstreams: 1 CNPC-2021-Art-95.pdf: 180715 bytes, checksum: de689ae28b0c057f2f962d12569f525f (MD5) Previous issue date: 2021

The production performance of a livestock herd can be compromised by various diseases. In sheep, maedi-visna (MV) infections, which have a chronic nature, are caused by a virus (maedi-visna virus (MVV)) belonging to the genus Lentivirus of the Retroviridae family. The infection can cause significant economic losses and has considerable health impacts on sheep breeding in production systems. Due to the importance of this disease in sheep flocks, the objective was to conduct a serosurvey of MVV in the states of Ceará (CE), Rio Grande do Norte (RN), Paraíba (PB), and Sergipe (SE). A total of, 3332 serum samples were collected in the four states, 1011 in CE, 931 in RN, 459 in PB, and 931 in SE, with the number of samples proportional to the actual herd size of each state. The samples were analyzed using the agar gel microimmunodiffusion test (AGID). Reproducers were revaluated using western blotting (WB). In addition to this serological survey, we administered an investigative questionnaire to identify possible risk factors that facilitate the introduction and spread of diseases (location, category, sex, breed type, creation system, production, herd size, and association with goats). After analysis of the sera using the AGID test, there was zero prevalence. Revaluating breeders by WB revealed a 5.5% prevalence of MV in the four states studied, with prevalences for the states of CE, RN, Paraiba, and SE of 2.3% (2/88), 10.4% (8/77), 3.6% (1/28), and 4.7% (2/42), respectively, corresponding to 13 breeders containing antibodies to the virus. These findings emphasized that the choice of diagnostic tests is extremely important for the early detection of seropositive animals and thus the prevention of the spread of the virus among herds in the region. [Estudo soroepidemiológico da maedi-visna em ovinos nos estados do Ceará, Rio Grande do Norte, Paraíba e Sergipe]. Resumo: O desempenho produtivo de um rebanho pode ser comprometido por diversas enfermidades. Em relação aos ovinos, à ocorrência da Maedi - Visna (MV) doença infecciosa, de caráter crônico, causada por um vírus (Maedi-Visna Vírus - MVV) pertencente ao gênero Lentivirus da família Retroviridae. A infecção pode causar importantes perdas econômicas e elevados impactos sanitários nos sistemas de produção da ovinocultura. Em virtude da importância desta enfermidade nos rebanhos ovinos, o objetivo do estudo foi realizar um levantamento soroepidemiológico do vírus da Maedi - Visna (MVV) nos estados do Ceará (CE), Rio Grande do Norte (RN), Paraíba (PB) e Sergipe (SE). Para tanto, foram coletadas 3332 amostras de sangue nos quatro estados, sendo 1011 do CE, 931 do RN, 459 da PB e 931 de SE, sendo este número de amostras proporcional ao rebanho efetivo de cada estado. As amostras foram analisadas utilizando o teste de microimunodifusão em gel de ágar (IDGA). Os reprodutores foram reavaliados pela técnica de Western Blot (WB). Associado a esse levantamento sorológico foi aplicado um questionário epidemiológico para identificar possíveis fatores de risco que podem facilitar a introdução e disseminação de enfermidades (localização, categoria, sexo, tipo racial, sistema de criação, produção, tamanho de rebanho e associação com caprinos). Após análise dos soros pelo teste de IDGA foi verificada uma soroprevalência nula nos rebanhos estudados. Os reprodutores reavaliados pelo WB apresentaram uma prevalência geral de 5,5% da MV nos quatro estados estudados, sendo que os estados do Ceará, Rio Grande do Norte, Paraíba e Sergipe apresentaram, 2,3% (2/88), 10,4% (8/77), 3,6% (1/28) e 4,7% (2/42) respectivamente, correspondendo a 13 reprodutores que apresentaram presença de anticorpos. Diante desses resultados, ressalta-se que a escolha dos testes diagnósticos é de extrema importância para que haja uma detecção precoce de animais soropositivos, e assim evitar a disseminação do vírus nos rebanhos da região. Made available in DSpace on 2018-09-26T00:42:27Z (GMT). No. of bitstreams: 1 CNPC2018Seroepidemiological.pdf: 312914 bytes, checksum: d6f6707fe9acafbcfa45385a89af2191 (MD5) Previous issue date: 2018-09-25