Helminth parasites in feces of Antillean manatees Trichechus manatus manatus (Sirenia:Trichechidae) in Mexico: Gulf of Mexico and Caribbean

Abstract

Background. Low helminth diversity has been reported in West Indian manatees (Trichechus manatus ). Most studies were conducted on the Florida sub species T. m. latirostris in subtropical environments, therefore limited information is available for the tropical Antillean subspecies T. m. manatus. In Mexico, there are apparently two population units of T. m. manatus. Goals. The objective of this study was to survey the presence and prevalence of helminth parasite eggs in the feces of T. m. manatus from the Gulf of Mexico (GM) and Caribbean coasts (CAR) of Mexico. Methods. We used 31 fecal samples collected from GM (n = 22) and CAR (n = 9), from 2005 to 2008. Feces were fixed and preserved in 70% ethanol until analysis. Both floatation and sedimentation techniques were used. Helminth eggs were identified using specialized literature and graphic catalogs. Results. We found parasite eggs in 61.2% of feces; all samples from CAR had helminths. We documented eggs from five helminths: three digenetic (Chiorchis fabaceus, C. groschafti, and Pulmonicola cochleotrema) and two Nematoda (Heterocheilus tunicatus and Ascarididae gen. sp.). Two species were found exclusively from GM, one exclusively from CAR, and two species were common to both locales. Conclusions. Diversity was consistently low in the samples. Four of the species found are common to Florida and Caribbean islands and one is a new registry for this host. Future examination of manatee carcasses could confirm the presence of adult helminth species for new registries for this host.