Control measures recommended for goat gastrointestinal nematode infections after analysis of infection dynamics in the semiarid region of Brazil

portuguesEste trabalho objetivou determinar medidas de controle de nematodeos gastrintestinais de caprinos no semiarido nordestino apos analise da dinâmica das infeccoes helminticas durante a seca, a evolucao da carga parasitaria apos as primeiras chuvas e as diferencas de susceptibilidade entre caprinos de distintas categorias e idades. Em cinco propriedades, de marco de 2013 a janeiro de 2015, foram coletadas, mensalmente, fezes de todos os caprinos para contagem de ovos. Em nenhuma propriedade foi necessario vermifugar durante os periodos de seca. Em 2013, com precipitacoes de 265-533 mm anuais, nao foi necessario vermifugar durante o periodo de chuva. No entanto, em 2014, com precipitacoes de 604-778 mm, foi necessario vermifugar 60-90 dias apos as primeiras chuvas em tres propriedades. Nessas tres propriedades foi encontrada multirresistencia aos anti-helminticos. Foi constatado que o OPG das cabras lactantes foi significativamente maior do que o OPG das cabras secas e dos cabritos. Em conclusao, na regiao semiarida, geralmente, nao e necessario o tratamento das cabras pastejando na caatinga durante a estacao seca. Na estacao chuvosa, a carga parasitaria aumenta 2-3 meses apos as primeiras chuvas. Tanto na seca quanto nas chuvas, o produtor deve monitorar o rebanho mediante OPG ou por outros criterios (anemia, edema submandibular) para determinar a necessidade de vermifugacao EnglishThis study aimed to determine control measures for gastrointestinal nematodes in goats in the northeastern semiarid after analyzing the dynamics of gastrointestinal helminths during the drought, the evolution of the parasitic load after the first rains and the differences in susceptibility between goats of different categories and ages. Five farms were studied from March 2013 to January 2015. Feces were collected from all goats every month, for fecal egg counts (FECs). No treatment was required on any farm during the dry period. In 2013, with annual rainfall of 265-533 mm, treatments were not necessary during the rainy season. However, in 2014, with rainfall of 604-778 mm, treatments were necessary 60-90 days, after the first rains. On three farms, gastrointestinal nematodes showed multiple anthelmintic resistance. The FECs from lactating goats were significantly higher than from dry and young goats. In conclusion, in the Brazilian semi-arid region (Caatinga biome), it is generally unnecessary to treat grazing goats during the dry season. In the rainy season, the parasite load increases 2-3 months after the first rains. In both, the dry and the rainy season, farmers should monitor their herds by means of FEC or another criterion (anemia or submandibular edema), to determine the need to treat