Health Assessment and Seroepidemiologic Survey of Potential Pathogens in Wild Antillean Manatees (Trichechus manatus manatus)

Abstract

The Antillean manatee (Trichechus manatus manatus), a subspecies of the West Indian manatee, inhabits fresh, brackish, and warm coastal waters distributed along the eastern border of Central America, the northern coast of South America, and throughout the Wider Caribbean Region. Threatened primarily by human encroachment, poaching, and habitat degradation, Antillean manatees are listed as endangered by the International Union for the Conservation of Nature. The impact of disease on population viability remains unknown in spite of concerns surrounding the species’ ability to rebound from a population crash should an epizootic occur. To gain insight on the baseline health of this subspecies, a total of 191 blood samples were collected opportunistically from wild Antillean manatees in Belize between 1997 and 2009. Hematologic and biochemical reference intervals were established, and antibody prevalence to eight pathogens with zoonotic potential was determined. Age was found to be a significant factor of variation in mean blood values, whereas sex, capture site, and season contributed less to overall differences in parameter values. Negative antibody titers were reported for all pathogens surveyed except for Leptospira bratislava, L. canicola, and L. icterohemorrhagiae, Toxoplasma gondii, and morbillivirus. As part of comprehensive health assessment in manatees from Belize, this study will serve as a benchmark aiding in early disease detection and in the discernment of important epidemiologic patterns in the manatees of this region. Additionally, it will provide some of the initial tools to explore the broader application of manatees as sentinel species of nearshore ecosystem health.

SEASONAL PREVALENCE OF ANTIBODIES TOLEPTOSPIRA INTERROGANSIN ANTILLEAN MANATEES FROM A LANDLOCKED LAKE IN TABASCO, MEXICO

“…Lounsbury et al (2001) documented serovars canicola, icterohemorragiae, autumnalis, pyrogenes, hardjo, and pomona from Florida and the Gulf of Mexico. Aragó n-Martínez (2008) and Sulzner et al (2012) found canicola and icterohemorragiae in Antillean manatees and Mathews et al (2012) found icterohemorragiae in Amazonian manatees. Serovars pomona, hardjo, and bratislava have been associated with bovine, porcine, and equine livestock (Khairani-Bejo et al 2004).…”

“…However, in other regions, prevalence was lower than in our study. These include Florida (25%), Belize (23%), and Caribbean coasts of Mexico (14.3%; Lounsbury et al 2001;Sanvicente 2005;Sulzner et al 2012; Table 2). For the Amazonian manatee, reported prevalence was 17.3% (Mathews et al 2012).…”

“…Antibodies to some serovars positive by MAT in this study have been found in West Indian manatees (in both Antillean and Florida subspecies) and in the Amazonian manatee. Serovar bratislava was reported in Belize (Sulzner et al 2012), Veracruz (Aragó n-Martinez 2008), Tabasco, and Quintana Roo (Sanvicente 2005), and in Florida along the coasts of the Atlantic and the Gulf of Mexico (Lounsbury et al 2001). Lounsbury et al (2001) documented serovars canicola, icterohemorragiae, autumnalis, pyrogenes, hardjo, and pomona from Florida and the Gulf of Mexico.…”

“…However, diseases and potential pathogens are less studied in tropical waters. Antibody to Leptospira interrogans, a widespread bacterium (Levett 2001), has been reported for Florida manatees (T. m. latirostris) (Lounsbury et al 2001), Antillean manatees (Sulzner et al 2012), and Amazonian manatees (T. inunguis) (Mathews et al 2012). As part of a study to characterize seasonal effects in manatees of the region, we surveyed antibodies to L. interrogans serovars in nonmanaged, semicaptive Antillean manatees isolated in a landlocked urban lake.…”

Detection of infection with Leptospira spp. in manatees (Trichechus inunguis) of the Peruvian Amazon

“…Little is known of the causes of death or the prevalence of zoonotic organisms in manatees from Peru; however, Leptospira spp. have been reported to cause mortalities in marine mammals (Visser et al, 1991;Higgins, 2000;Mackereth et al, 2005;Bossart et al, 2012;Sulzner et al, 2012).…”