Parasitos apicomplexa de matrizes caprinas da raça Canindé, na estação experimental terras secas, Rio Grande do Norte

Abstract

The goat production is a widely exploited activity in tropical countries and has great social and economic importance. Despite this, many diseases affect goats among which, parasitosis. In this context, some parasites of the phylum Apicomplexa are of great importance, due to high prevalence, impact on productivity and reproduction of animals, in addition to zoonotic's characteristics of some species. The aim of this study was to monitor the infections by Eimeria spp., Cryptosporidium spp.e Toxoplasma gondii in goats matrices of Canindé breed, raised in semi-intensive regime at the Experimental Station Terras Secas, Pedro Avelino, Rio Grande do Norte. Crops of stool samples and blood were carried out from August 2010 to July 2011. To monitor Eimeria spp. Infection it was realized the oocyst count per gram of feces (OoPG) and the identification of species based on morphological and morphometric parameters of sporulated oocysts. The infection by Cryptosporidium spp. was verified by oocyst's search in fecal smears stained with modified Zielh- Neelsen technique. To monitor infection by T. gondii was performed the conventional ELISA and avidity. The statistical analysis of the correlation between the average oocysts disposal and intensity of rainfall was verified by the t test for the regression coefficients. And the correlation between the oocysts shedding and reproductive status of matrices, it was made an analysis of variance. Statistical analyzes were performed using the R Core Team program, version 2015, assuming a significance level of 0.05%. Eimeria oocysts were detected in 85.24% of feces samples. Nine species of Eimeria have been identified: E. alijevi, E. arloingi, E. apsheronica, and. caprovina, E. christenseni, E. hirci, E. joechijevi, E. Ninakohlyakimovae e, E. caprina. The intensity of rainfall is related to the elimination of oocysts in the months in which the rainfall intensity was greater than 100 mm there was a greater elimination of oocysts in the feces (p = 0.00). Pregnant and calved matrices tend to eliminate more oocysts of Eimeria than dry, and this difference was statistically significant (p = 0.00). Of 405 fecal smears examined, nine were Cryptosporidium spp, representing 2.20% of the samples.; being the oocysts present in a sample taken in August, one in January, three in February, three in March and one in June. Of the 215 serum samples tested by ELISA, 93 (43.26%) were considered reactive to T. gondii. The greater reactivity rate was observed in July 2011 (94.10%). In the samples considered reactive, it was performed the ELISA test of antibody avidity of which 65 (69.90%) had high avidity antibodies, indicative of chronic infection and 28 (30.10%) had low avidity, indicative of acute infection. The infection by Eimeria spp. constitutes a problem for the flock since the five considered pathogenic species for goats were observed with high prevalence throughout the study period. The infection by Cryptosporidium spp. a low risk, but this is continuous, since the elimination of Cryptosporidium spp. It occurred at several points over the study time. The risk of vertical transmission of T. gondii can be considered high, since approximately one third of matrices were in the acute phase of infection.