Freqüência de Giardia lamblia em cães atendidos em clínicas veterinárias de Porto Alegre, RS, Brasil Frequency of Giardia lamblia in dogs attended by veterinary clinics in Porto Alegre city, RS, Brazil

A pesquisa de cistos de Giardia lamblia em fezes de cães oriundos de clínicas veterinárias de Porto Alegre, RS, Brasil, foi realizada pelo método de FAUST et al. (1939). Das 526 amostras analisadas, 38% (198) foram positivas para cistos de G. lamblia, sendo 22% (116) constituídos por animais menores de 11 meses de idade e 16% (82) constituídos por animais com 12 meses ou mais de idade. Houve diferença significativa (p<0,05) entre os grupos pelo teste do c². Dos animais pesquisados, 54% (285) eram machos, e, destes, 20% (104) apresentaram cistos em suas fezes. Dos 46% (241) de fêmeas analisadas, 18% (95) tiveram suas amostras positivas para cistos de G. lamblia, não havendo diferença significativa entre os resultados encontrados pelo teste do c². Os animais jovens (menores de 11 meses de idade) apresentaram uma taxa de positividade duas vezes maior que os animais com idade superior a 12 meses, e a variável sexo não apresentou associação com a positividade.<br>The method of Faust et al. (1939) was utilized for detection of Giardia lamblia cysts in feces from dogs in Porto Alegre city, Rio Grande Sul State, Brazil. From the 526 analyzed samples 38% (198) showed positive results for the presence of G. lamblia cyst, so 22% (116) belonged to group one, formed by animals that were less than eleven months old; and 16% (82) belonged to group two, formed by animals that were twelve months or older. There was a significant difference (p<0,05) among the two groups checked by the c² test. From the animals researched, 54% (285) were male dogs and from these 20% (104) presented cysts in their feces. From the other 46% (241), which were female dogs, 18% (95) presented positive results for the cysts of G. lamblia in their sample. The c² test applied to these data showed that there was not any significant difference between the results found in female or male dogs of all ages. Based on these results, we can come to the conclusion that 38% of the analyzed dogs showed positive results for the infection of G. lamblia and that the younger animals those aged less than eleven months presented a rate of risk to get infected which is two times bigger than the ones for the animals with 12 months or older, as well as, the fact that the sex of the animals did not present any association to the positive results of infection.