Experimental evaluation of birds as disseminators of the cosmopolitan tick Rhipicephalus sanguineus (Acari: Ixodidae).

Rhipicephalus sanguineus is believed to be the most widespread tick species of the world and its dissemination seems to rely on the diffusion of its main host, the dog. Empirical observations indicate that several bird species in urban areas regularly steal dog food. Such circumstances create a chance for R. sanguineus ticks to climb on birds and carry ticks to another site. In this work we evaluated experimentally the likelihood of birds (chicks) to either feed and/or carry R. sanguineus ticks from an infested site to another and to infest a host (rabbit) in the new location. Chicks were not suitable hosts for R. sanguineus ticks. Not a single adult tick engorged on chicks, yield as well as weight of engorged larvae and nymphs were very low and feeding period of these ticks was very long. However, a few larvae and, chiefly, nymphs were delivered to a new location either mechanically or after attachment and engorging total or partially on chicks. A few of these ticks fed successfully on rabbits. Further evidence on the capacity of birds to introduce R. sanguineus into non-infested dog settings should be provided by systematic examination of birds from urban areas, close to tick infested households.

Evaluation of Toxoplasma gondii and Neospora caninum infections in sheep from Uberlândia, Minas Gerais State, Brazil, by different serological methods.

Toxoplasmosis and neosporosis have been recognized as economically important diseases with considerable impact on the livestock industry. Considering the scarce information on the occurrence of Toxoplasma gondii and Neospora caninum infections in sheep from Uberlândia, Minas Gerais State, Brazil, this study aimed to investigate the frequency of antibodies against these parasites in sheep sera from this region by using different serological methods. A total of 155 sheep serum samples were analyzed by the indirect fluorescence antibody test (IFAT) and enzyme-linked immunosorbent assay (ELISA) for the detection of IgG against T. gondii and N. caninum. Seroreactivity by IFAT showed 80% of samples with titers between 512 and 2048 for T. gondii (cutoff ≥ 64) and 78% presenting titers between 50 and 200 for N. caninum (cutoff ≥ 50). Seroreactivity by ELISA showed 75% of samples with ELISA index (EI) between 2.0 and 3.0 for T. gondii (cutoff ≥ 1.3) and 54% presenting EI between 1.3 and 2.0 for N. caninum (cut off ≥ 1.3). Discordant results by both tests were analyzed by immunoblot, resulting in a total seropositivity of 61% for T. gondii and 23% for N. caninum, with 41% to T. gondii only, 3% to N. caninum only, and 20% to both parasites. There was a significant positive association between seropositivity to T. gondii and age over one year (P<0.001), but such association was not found for N. caninum infection. In conclusion, as T. gondii and N. caninum infections are simultaneously present in sheep flocks of this region, it should be emphasized the importance to carry out a regular monitoring of Toxoplasma infection due to its high prevalence, its zoonotic potential and induction of reproductive disorders leading to economic losses. For neosporosis, sheep farmers should be instructed about the presence of the parasite in the flock, its risk factors and potential abortifacient role in sheep. Differential flock management could be valuable tool to establish the association of serological positivity and reproductive disease induced by N. caninum in sheep.

Helmintos e protozoários em fezes de javalis (Sus scrofa scrofa) criados em cativeiro / Helminths and protozoa in wild boars (Sus scrofa scrofa) feces raised in captivity

Faecal samples from 79 wild boars (Sus scrofa scrofa) were examined by sedimentation method, zinc sulfate flotation method, and centrifugal flotation in sugar solution for endoparasites research. The results showed that 97.5 por cento of the samples were positive for helminths and/or protozoa as follows: strongilides (70.9 por cento), Ascaris suum (46.9 por cento), Trichuris suis (29.1 por cento), Metastrongylus sp. (12.6 por cento), Strongyloides ransomi (3.8 por cento), Balantidium coli (38.0 por cento), Entamoeba spp. (15.2 por cento), Giardia spp. (1.3 por cento), Blastocystis sp. (12.6 por cento). The frequency of Entamoeba was higher in young animals. Coccidian oocysts were observed in 59.5 por cento samples and five species of Eimeria and one Isospora were recovered: Eimeria scabra (31.9 por cento), E. deblieck (31.9 por cento), E. perminuta (23.4 por cento), E. cerdonis (17.0 por cento), E. scrofae (12.8 por cento) and Isospora suis (12.8 por cento).

Ocorrência de babesiose canina no Município de Uberlândia, Minas Gerais / Incidence of canine babesiosis in Uberlândia, Minas Gerais

Babesia canis é um protozoário intraeritrocítico transmitido pelo carrapato Rhipicephalus sanguineus que acomete principalmente canídeos domésticos e silvestres, causando manifestações clínicas como anorexia, pirexia, hemoglobinúria, esplenomegalia, hemoglobinemia, anemia grave, podendo o animal recuperar-se lentamente ou morrer. O objetivo desta pesquisa foi determinar a ocorrência da doença em Uberlândia – MG e comparar os métodos de esfregaços sangüíneos de ponta de orelha e Reação de Imunofluorescência Indireta (RIFI) no diagnóstico desta enfermidade. Para realização deste trabalho, foram colhidos aleatoriamente soros de 143 cães atendidos no Hospital Veterinário da Universidade Federal de Uberlândia para exame de RIFI enquanto que 772 esfregaços sangüíneos de ponta de orelha foram feitos e corados pelo Giemsa para a pesquisa do hemoparasito. Após a padronização da RIFI, considerou-se positivo soros com diluição igual ou superior a 1:20 e como negativos soros com diluição inferior a 1:20. Dos soros testados, através da RIFI, 51,74% estavam positivos e 48,26% negativos. Dos esfregaços sangüíneos 2,72% eram positivos para babesiose, 87,83% negativos e 9,45% positivos para outros hemoparasitos. Através do teste Qui-quadrado observou-se diferença significativa, em nível de significância 5%, entre os métodos comparados.

Seroprevalence of Toxoplasma gondii infection in goats by the indirect haemagglutination, immunofluorescence and immunoenzymatic tests in the region of Uberlândia, Brazil.

A comparative study of the indirect haemagglutination (IHA), immunofluorescence (IFAT) and immunoenzymatic (ELISA) tests was carried out to determine the prevalence of Toxoplasma gondii antibodies in goats. One hundred seventy-four serum samples were obtained from four goat herds from the region of Uberlândia, State of Minas Gerais. The distribution of the animals, according to their origin, was as follow: 71 from herd I; 39 from herd II; 37 from herd III; and 27 from herd IV. Serum samples were analyzed by IHA, IFAT and ELISA, considering the reactivity of the serum samples at dilution > or = 1:64 as cut off titer for the three tests. A global seroprevalence of 18.4% was observed, with significantly higher positivity rate in the herd II (66.7%) and older animals (> 36 months). A high and significant positive correlation was found between the titers obtained by the IHA versus IFAT, IHA versus ELISA, and ELISA versus IFAT. Therefore, it can be concluded that the three analyzed tests have shown to be highly concordant and appropriate for epidemiological surveys of Toxoplasma infection in goats. Although the seroprevalence of T. gondii infection in goats is relatively low in this region as compared to other regions of the country, adequate management might be useful and essential to control the infection in the goat herds.

Detection of IgG antibodies to Neospora caninum and Toxoplasma gondii in dogs examined in a veterinary hospital from Brazil.

A total of 163 dogs with neuromuscular, respiratory and/or gastrointestinal disorders, was admitted at the Veterinary Hospital, Federal University of Uberlândia, Brazil, and submitted to serology for Toxoplasma gondii and Neospora caninum. Assays for T. gondii included indirect haemagglutination (IHA), indirect fluorescent antibody (IFAT-Tg), immunoenzymatic (ELISA), and immunoblotting (IB-Tg). Assays for N. caninum included IFAT-Nc and immunoprecipitation (IP-Nc). Based on concordant results by three serological tests (IHA, IFAT-Tg and ELISA) for T. gondii, and divergent results further confirmed by IB-Tg for reactivity to TgSAG1, the 163 sera were divided into two groups: 59 (36%) Tg-seropositive samples and 104 (64%) Tg-seronegative samples. Antibodies to Neospora were detected in 11 (6.7%) out of 163 analyzed dog sera, with 5 (3.1%) samples reactive to both parasites (Tg+/Nc+), and 6 (3.7%) reactive only to Neospora (Tg-/Nc+). Antibodies only to T. gondii were found in 54 (33%) samples. Among the 11 Neospora-positive sera analyzed by IB-Tg, the five sera Tg+/Nc+ showed strong reactivity to Toxoplasma antigens, especially to TgSAG1 (p30). No reactivity was observed to TgSAG1 in the six samples Tg-/Nc+. By IP-Nc, two highly immunodominant antigens (29 and 35kDa proteins) were recognized by all 11 IFAT-Nc positive sera. Our results suggest that the infection by N. caninum can be concomitantly present in dogs from this area, although less common, and therefore should be considered in the differential clinical diagnosis with T. gondii in dogs presenting neuromuscular, respiratory and/or gastrointestinal disorders.

Xenopsylla cheopis em cäes do Brasil: primeiro relato / Xenopsylla cheopis on dogs from Brazil: first report

For the first time, Xenopsylla cheopis (Rothschild) is recorded on dogs from Brazil, at the prevalence of 1.1 per cent in the city of Uberlândia, Minas Gerais State. Having in view the high occurrence of commensal rats in that municipality, as well as the opportunities for contact with domestic animals, this report should not be underestimated

Detection of Toxoplasma gondii-specific antibodies in dogs. A comparative study of immunoenzymatic, immunofluorescent and haemagglutination titers.

We evaluated the titers of anti-T. gondii antibodies by various serological tests in 40 serum samples from dogs exhibiting clinical signs of infectious diseases. Indirect immunofluorescence (IgG-IFI), indirect haemagglutination (IHA and M-Toxo) and immunoenzymatic (ELISA and PA-ELISA) tests were carried out. Titers > or = 64 were considered as positive. Anti-Toxoplasma antibodies were found in 9 (22.5%), 14 (35%), 14 (35%) and 12 (30%) samples, respectively for IHA, IgG-IFI, ELISA and PA-ELISA. The results showed that 57% were negative in all tests and 43% of the dogs presented antibodies to T. gondii; from these, 20% were positive in all three tests with high titers of antibodies and 23% were positive in only one or two tests with low titers of antibodies and mainly related to the IFI and ELISA tests. We observed 5 (12.5%) and 1 (2.5%) reactive samples, respectively, by M-Toxo and IHA with or without 2-mercapthoethanol, in the attempt to detect specific IgM. We can conclude that serodiagnosis of toxoplasmosis in dog have to be based on the combination of serological tests (IFI and ELISA) and with emphasis at the determination of the titers and the classes of the specific antibodies.

Eimeria spp (Schneider, 1875) em bezerros do Município de Uberlândia, Minas Gerais / Eimeria spp (Schneider, 1875) in calves from Uberlandia, Brazil

Foram colhidas amostras de fezes de 117 bezerros, de 15 a 180 dias de idade, para identificaçäo das espécies de Eimeria, que ocorrem em Uberlândia, MG. Cinquenta e cinco animais (47 por cento) apresentaram oocistos nas fezes e nove espécies de Eimeria foram identificadas. Destas somente E. alabamensis näo havia sido econtradas pelos autores nacionais

Distribuiçäo geográfica e freqüência da gasterofilose em equídeos abatidos em Araguari, Minas Gerais / Geographic distribution and frequency of gasterophilosis in slaughtered horses of Araguari, Minas Gerais

Em um estudo feito no Frigorífico FAVA S/A, Araguari, Minas Gerais, verificou-se que de 14.162 eqüídeos abatidos, procedentes de 9 estados brasileiros, no período compreendido entre 14 de maio de 1987 a 10 de maio de 1988, 31,49//achavam-se positivos para larvas de moscas do gênero Gasterophilus. Durante este período foram encontrados animais positivos procedentes de 7 estados: Mato Grosso do Sul (85,71//); Säo Paulo (75,95//); Paraná (65,61//); Goiás (44,02//); Mato Grosso ($2,03//); Minas Gerais (14,03//) e Pará (8,33//), enquanto animais negativos procederam de 2 estados: Espírito Santo e Rio de Janeiro. Foram estudados 226 municípios nesses estados e 77,43//desses apresentaram eqüídeos positivos para gasterofilose. A espécie identificada foi a G. nasalis