Com o objetivo de comparar variáveis epidemiológicas na toxoplasmose em ovinos e caprinos, amostras de soro de animais de propriedades localizadas em duas regiões do Estado de Pernambuco, Brasil, foram testadas pela reação de imunofluorescência indireta (RIFI) para detecção de anticorpos anti-Toxoplasma gondii. Dos 173 soros ovinos testados, em 35,3% foram encontrados resultados positivos, enquanto 40,4% dos 213 soros caprinos foram positivos à RIFI. Em ovinos, associações significativas foram encontradas para sexo e raça, mas não para região, tipo de manejo ou falha reprodutiva. Os resultados da RIFI para os caprinos foram significativamente associados ao sexo, raça, região, tipo de manejo e de exploração, mas não com a ocorrência de falhas reprodutivas.

Os antimicrobianos são amplamente utilizados na clínica veterinária e o uso indiscriminado destas drogas contribui com o aumento progressivo da resistência bacteriana. A resistência aos antibióticos é um sério problema do ponto de vista clínico e de saúde pública, devido ao tratamento dos animais tornar seus produtos e derivados fonte para resistência bacteriana na espécie humana. A origem da resistência pode ser genética ou não e independente de qual seja a forma de maior importância neste processo, o fato é que o número de novas bactérias resistentes e patogênicas para os animais e humanos cresce mais rápido do que a capacidade dos laboratórios e indústrias produzirem novas drogas.

Toxoplasma gondii is a cosmopolitan protozoan parasite of warm-blooded animals that causes high rates of infection in mammals and birds. Sparrows (Passer domesticus) are synantropic birds which are distributed worldwide. They serve as intermediate hosts for the parasite but are quite resistant to toxoplasmosis. The aims of this study were to determine the frequency of T. gondii infection in sparrows using serologic and molecular tests, and to investigate related parasites, such as Neospora caninum and Hammondia sp., using a nested PCR for Toxoplasmatinae DNA followed by sequence analysis of the PCR amplicons. A total of 293 sparrows were trapped at the states of Bahia and Pernambuco, Brazil. Tissues of 40 animals were available for molecular tests. Antibodies to T. gondii were found in 1.02% (3/293) of animals using a hemagglutination test, with titers ranging from 1:32 to 1:128. Toxoplasmatinae DNA was detected in 10/40 (25%) sparrows; after nucleotide sequencing, T. gondii was confirmed in 7/40 (17.5%) birds and N. caninum in 3/40 (7.5%) animals. Sparrows from Brazil were confirmed as intermediate hosts of T. gondii, that reinforces the potential importance of these birds on the transmission of the parasite to cats and other animals that may predate sparrows. In addition, N. caninum was detected for the first time in sparrows. To the authors' knowledge, this is the first wild synantropic bird species identified as intermediate host of N. caninum. These findings seem to have a great epidemiologic impact because of the cosmopolitan distribution of sparrows and due to their increasing population in urban and rural areas.

Worldwide comparison of Toxoplasma gondii isolates from free-range chickens ( Gallus domesticus ) has indicated that T. gondii isolates from Brazil are phenotypically and genetically different from isolates from other countries; most strains from Brazil are pathogenic to mice, there is great genetic variability, most isolates are nonclonal, and Type II is absent or rare. The prevalence of T. gondii in 50 free-range chickens from the island of Fernando de Noronha, Brazil (this island is 350 km from the mainland) was determined. Antibodies to T. gondii were assayed by the modified agglutination test (MAT); 42 (84%) chickens had titers of 1ratio5 in 2, 1ratio10 in 4, 1ratio20 in 3, 1ratio40 in 6, 1ratio80 in 6, 1ratio160 in 5, 1ratio320 in 3, and 1ratio640 or higher in 13 chickens. Hearts of 40 seropositive chickens were bioassayed individually in mice. Toxoplasma gondii was isolated from 24 chickens with MAT titers of 1ratio5 or higher; the isolates were designated TgCKBr210-233. None of the isolates was pathogenic for mice. The restricted fragment length polymorphism using 10 markers revealed 6 genotypes, including the Type II, Type III, and 4 new chicken genotypes (#59-#62) that were different from genotypes so far reported in Brazil. All 24 isolates were successfully genotyped; 15 isolates were Brazil chicken type #59, 1 type #60, 1 type #61, 1 type #62; 5 were Type II (with Type I allele at the Apico locus); and 1 isolate was clonal Type III. Results in this study indicate that T. gondii on this island consists of unique genotypes as well as clonal genotypes that are dominant in Europe and North America.

At present, bovine neosporosis is an important worldwide concern because of its wide geographic distribution and economic impact. Abortion is the main clinical sign of bovine neosporosis in both dairy and beef cattle. Ruminant challenge models are critical to evaluate potential vaccine candidates to help tackle bovine neosporosis and to study pathogenesis and host responses to infection. Several research groups have developed ruminant models of Neospora caninum infection independently of others, resulting in a high degree of variability due to the use of different species of animals, breeds, strains/isolates of N. caninum, doses, routes and times of inoculation. Standardization is greatly needed to advance research in a more collaborative, timely and efficient manner. In the absence of widely accepted international guidelines, this manuscript serves to summarize and discuss the different models and parameters currently in use. Parameters essential for the development of non-pregnant and pregnant ruminant models are outlined and the main knowledge gaps are identified. This information could act as the basis to develop a consensus for international standard guidelines for ruminant models of neosporosis that would be helpful for researchers in this field worldwide.