author(s)
Silvia Miguélez, Ana M Araújo, Iván Francisco, José Suarez, Rita Sánchez-Andrade, Adolfo Paz-Silva and María Sol Arias

abstract
Gasterophilosis is a myiasis related with gastric ulcers in equids and even colics. A serological survey to assess the presence of IgG antibodies against Gasterophilus spp. in horses from an oceanic climate area was conducted. A total of 672 blood samples were analyzed by an enzyme-linked immunosorbent assay (ELISA) and excretory/secretory antigens from G. intestinalis second-instar larvae. Results were analyzed according to intrinsic and extrinsic factors. Sixty-seven percent of the horses were seropositive. The Arabian Pure Blood and the autochthonous Pura Raza Galega showed the highest and the lowest exposure to horseflies, respectively. Geldings showed the maximum values of seroprevalence (96%), while mares achieved the minimum. The highest percentage of seropositivity was reported in the oldest ones (72%). Significant differences were recorded (P<0.05). Our findings underline a high risk of sensitization among horses to bot fly in regions with an oceanic climate.