Seasonal variation of gastrointestinal parasitic infections in goats and sheep in São Luís, Maranhão, Brazil

ABSTRACT This study aimed to analyze the seasonal variation of gastrointestinal parasitic infections in goats and sheep in São Luís, Maranhão, Brazil. Fecal samples were collected directly from the rectal ampulla of the animals to count the eggs per gram in the feces at 30-day intervals over the 12-month study period. This study included 40 small ruminants, comprising 22 goats (14 sows, 6 kids, and 2 sires) and 18 sheep (13 sows, 4 lambs, and 1 sire). The study assessed the variation in the excretion of gastrointestinal nematode eggs during the dry and rainy seasons. Coproculture was performed to identify third-stage larvae. In the 12 months of research and monthly sample collections, 95.9% and 82.3% of the eggs detected were endoparasites in the fecal samples of the goats and sheep, respectively. Eimeria spp. oocysts were present in 50.6% and 30.4% of the goat and sheep fecal samples, respectively. The results indicated that the mean number of eggs per gram of feces was higher in the rainy season than in the dry season in both goats and sheep. The genera of gastrointestinal nematodes identified via monthly coproculture tests were Haemonchus sp., Trichostrongylus sp., and Oesophagostomum sp. Thus, gastrointestinal nematode parasitism was higher in goats and sheep during the rainy season than in the dry season, and the genera Haemonchus sp. and Trichostrongylus sp. were the most prevalent.