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Parasitic infection is recognized worldwide as a limiting factor in the production of goats, and various control methods are used to reduce economic losses, often without considering the epidemiology of the parasites. This has led to the development of highly tolerant parasite populations and the presence of chemical residues in the beef and milk. The objective of this study was to determine the level of knowledge of goat farmers about parasitic diseases and to correlate this with the epidemiology of endoparasites and parasite control practices in goat farms in the state of Minas Gerais, Brazil. The analysis was based on a questionnaire applied by trained veterinarians. The sample was homogeneous throughout the state, covering 18.4% (157/853) of municipalities. Eighty-four dairy goat farms in 81 municipalities and 200 properties with beef goats in 76 municipalities were evaluated. The herd size per goat farm ranged from 4 to 57 (average 24) for beef herds and from 2 to 308 (average 63) for dairy farms. The majority of the beef herd production was extensive and semi-extensive (98.5%), while the dairy herds were maintained under intensive farming (98.8%). The mixed production of goats and sheep was reported by 36.5% of beef goat farmers and by 20.2% of dairy goat farmers. Among the beef goats farms on which the technological level was determined, 2.0% were categorized as having high technological level, 34.5% as medium, and 63.5% as low. Of the 84 dairy farms, 30% operated at a high, 47% at a medium, and 23% at a low technological level. The adoption of practices to reduce parasitism, such as the quarantine of animals, treatment of newly arrived animals, regular cleaning of the floor, and technical assistance, was significantly higher on dairy farms than on beef farms. Although 85.7% of dairy farmers and 83% of beef farmers medicate their animals, the treatments were performed without technical criteria, and deworming intervals ranged from 30 to 120 days or more. The average interval between treatments was significantly longer in dairy goat herds (4.8 months) than in the beef herds (3.6 months). The most commonly used drugs were macrocyclic lactones (37.7% in dairy and 39.5% in beef herds) and benzimidazoles (48.9% in dairy and 31.5% in beef herds). Goat production in Minas Gerais is still in its infancy, and even though using a control program associated with other health practices, producers still rely heavily on chemicals to get satisfactory results.

Corynebacterium pseudotuberculosis is the etiologic agent of caseous lymphadenitis, which is a serious, economically important problem for sheep production. We examined the seroprevalence of infection by C. pseudotuberculosis and possible risk factors associated with caseous lymphadenitis in sheep herds of the state of Minas Gerais, Brazil. Samples were collected from 642 sheep from 97 farms. Sera of all of the sheep were tested with ELISA for antibodies against C. pseudotuberculosis. A questionnaire was applied to gather data on the farm, the sheep herd, the farmer, and individual animal data (breed, sex and age). This is the first sero-epidemiological survey for caseous lymphadenitis in sheep herds in Minas Gerais. We found a high real prevalence, much higher than that suggested from information obtained with the questionnaire, which points to the scarcity of vaccination against caseous lymphadenitis in the sample evaluated. Only a small proportion of the farmers declared that cases of this disease were present in their flocks. The frequency of seropositive sheep varied significantly with breed (χ2 test, P = 0.021). Age group also significantly affected the percentage of seropositivity (χ2 test, P = 0.049), the highest frequency being found in adult animals (more than 12 months old), when compared to the 5–12 months old group (χ2 test, P = 0.021). The prevalence of infection with C. pseudotuberculosis in sheep in the state of Minas Gerais was estimated to be 70.9% (95% confidence interval (CI): 64.7–77.0%) and the prevalence of infected flocks being 95.9% (95% CI: 89.8–98.9%). We concluded that C. pseudotuberculosis infection is widely disseminated in sheep flocks in Minas Gerais and that caseous lymphadenitis control and eradication programs are necessary in this state.

p. 1-5 Submitted by Edileide Reis (leyde-landy@hotmail.com) on 2014-03-13T17:06:10Z No. of bitstreams: 1 Roberto Meyer.pdf: 740113 bytes, checksum: f881405072d7590d7eee75b5cc556ce8 (MD5) Approved for entry into archive by Patricia Barroso (pbarroso@ufba.br) on 2014-03-13T18:25:25Z (GMT) No. of bitstreams: 1 Roberto Meyer.pdf: 740113 bytes, checksum: f881405072d7590d7eee75b5cc556ce8 (MD5) Made available in DSpace on 2014-03-13T18:25:25Z (GMT). No. of bitstreams: 1 Roberto Meyer.pdf: 740113 bytes, checksum: f881405072d7590d7eee75b5cc556ce8 (MD5) Previous issue date: 2011 Background Caseous lymphadenitis (CLA), caused by Corynebacterium pseudotuberculosis, is one of the most important diseases of sheep and goats, causing considerable economic losses for herd owners. Results We assessed the seroprevalence of infection with C. pseudotuberculosis in 805 sheep from 23 sheep farms that supply slaughterhouses in the state of Minas Gerais; we also analyzed management practices that could be associated with CLA occurrence, used on these and nearby farms that also supplied animals to the slaughterhouse (n = 60). The serum samples for assaying CLA infection were taken at the slaughterhouse. Frequency of infection with C. pseudotuberculosis was estimated at 43.7%, and farm frequency was estimated at 100%. Management practices were analyzed through a questionnaire. All farmers (60/60) had extensive/semi-extensive rearing system; 70.0% (42/60) identified sheep individually; 11.7% (7/60) had periodical technical assistance; 41.7% (25/60) disinfected the facilities; 86.7% (52/60) used barbed wire fences and did not implement adequate CLA control measures; only 11.7% (7/60) of breeders reported vaccination against C. pseudotuberculosis; 13.3% (8/60) took note of animals with clinical signs of CLA; 1.7% (1/60) opened and sanitized abscesses, and isolated the infected animals; 10.0% (6/60) knew the zoonotic potential of this disease and 1.7% (1/60) of the farmers culled animals in case of recurrence of abscesses. Conclusions It can be concluded that C. pseudotuberculosis infection is widely spread in sheep flocks in Minas Gerais state in Brazil and that there is a lack of good management measures and vaccination, allowing transmission of this infectious agent throughout the production network.

O presente trabalho foi o primeiro estudo soroepidemiológico da linfadenite caseosa em rebanhos caprinos no Ceará, Brasil, utilizando banco de 3239 soros de caprinos coletados em 127 propriedades em 29 municípios do Estado, em 1997. Em cada propriedade foi aplicado um questionário, contendo questões relativas aos aspectos da propriedade, do rebanho e dados individuais dos caprinos amostrados. Com base nos resultados sorológicos obtidos em teste imunoenzimático (ELISA-indireto) frente a proteínas secretadas de Corynebacterium pseudotuberculosis foram calculadas a prevalência e as freqüências nos estratos, objetivando-se verificar a existência de diferenças significativas entre os resultados obtidos utilizando-se o teste Qui-quadrado. A análise de fatores de risco foi realizada por meio de regressão logística multivariada com auxílio do programa computacional SPSS®15.0. A soroprevalência real encontrada foi de 26,2% dos caprinos e em 82,7% das propriedades foi encontrado pelo menos um animal sororreagente. Diferenças significativas foram encontradas nas prevalências para variáveis como exploração de leite e uso de brinco ou tatuagem para identificação. Devido à alta prevalência nas propriedades não foi possível determinar os fatores de risco para a linfadenite caseosa. The present work is the first seroepidemiological study on caseous lymphadenitis in goat herds in the state of Ceará, Brazil. Serum samples were collected from 3239 goats from 127 rural properties from 29 municipals districts in 1997. In each property was applied a questionnaire comprehending information about the management and the animals. The seroprevalence was established in the results of an indirect enzyme-linked immunosorbent assay (ELISA) that detects anti-bodies against Corynebacterium pseudotuberculosis. Prevalence values were calculated using the software WinEpiscope®2.0 and 26,2% of the goats tested positive for caseous lymphadenitis and 82,7% of flocks presented at least one seropositive animal. The influence of the different variables on the seroprevalence of CL was evaluated using Pearsons ² method with software SPSS®15.0. Goats managed under milk production system had a significantly higher seroprevalence of CL and the use of eartags or tattoos to identify the animals is important in the transmission of the disease. The high seroprevalence of CL in the properties incapacitate the analysis of risk factors.