Hematology and Clinical Biochemistry Profiles in Antillean Manatee Trichechus manatus manatus from Different Types of Captivity and Free Living in Northeast Brazil

Abstract

The Antillean manatee Trichechus manatus manatus can be found along the northern and northeastern coasts of Brazil. Previous studies on the clinical biochemistry of these animals were conducted in North America and the Caribbean, whereas little is known regarding these parameters in South American manatee populations. Accordingly, the objective of the present study was to examine the hematology and clinical biochemistry of Antillean manatees of different sexes and from different environments in northeast Brazil. Whole-blood and serum samples were obtained from healthy individuals. The hemogram analysis was performed and the levels of blood biochemical components were determined using an automated platform. The only statistically significant difference observed in the hemogram was a higher number of heterophils in manatees that were screened during the dry season of the year. Clinical biochemistry profiling revealed that free-ranging manatees presented lower levels of creatinine. Albumin was detected in higher concentrations in animals from rehabilitation captivity, and amylase presented higher levels in manatees that were kept in acclimation captivity. Free-ranging manatees showed higher serum aspartate aminotransferase levels than manatees in rehabilitation captivity. These results can aid veterinarians and conservation professionals in the development of better captive management procedures and in the clinical approach to manatees.

Blood Reference Intervals for Antillean Manatees (Trichechus manatus manatus) from Puerto Rico

“…Erythrocyte and total leukocyte counts measured in this study were similar to those previously reported for manatees in Guyana, Mexico, Belize, Brazil, and Florida [ 6 – 9 , 14 , 25 ] ( Table 6 ). Red blood cell count was highest in neonates (>3.0 × 10 6 /mm 3 ) and decreased as manatees grew and learned to dive [ 6 , 32 ], as evident in significant variation among age classes observed in the study ( Table 2 ).…”

“…Aspartate aminotransferase appears to be of little or no clinical value in manatees [6]. However, values for Puerto Rico were comparable to those described for Florida [6,24], Guyana [7], and Brazil [14] but lower than in Mexico and Belize [8,9]. Increased alkaline phosphatase may be present in growing, young mammals in some terrestrial species associated with osteoblastic activity [36], as seen in our reference ranges of Puerto Rican manatee calves versus adults.…”

“…While differences in immunoglobulin G (IgG) reference values for manatees from Florida, Colombia, and Puerto Rico were found [ 31 ] and comparisons were made on hematological and serum chemistry reference ranges between Antillean manatees in Guyana and Florida manatees [ 7 ], these studies found that the majority of hematological and serum chemistry results were similar to those reported for the Florida manatee. Blood parameters of Antillean manatees in Brazil were also evaluated, and differences between sexes and environments were discussed [ 14 ]. Tabulated reference ranges for both subspecies of West Indian manatees (Antillean and Floridian) from Guyana, Mexico, Belize, Brazil, and Florida ( Table 6 and 7 ) were used to discuss similarities or differences between these populations in comparison to hematology and blood chemistry reference ranges found for Puerto Rico.…”

“…While Bossart et al [6] included alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase in the liver-associated enzymes, to date, these analytes are considered more indicative of the muscular system [22]. Alanine aminotransferase values for Puerto Rico were significantly higher in adults compared to calves (Table 4) and were similar to Mexico, Belize, and Florida [6,8,9,24] but higher than those found in Brazil [14]. Aspartate aminotransferase appears to be of little or no clinical value in manatees [6].…”

“…However, blood reference ranges or values can di er among populations of the same species and vary according to age, sex, diet, environment, physiological conditions, and activity level. e hematology and blood chemistry of various Antillean manatee populations have been documented for Guyana [7], Mexico [8], Belize [9,10], Brazil [11][12][13][14], and for the Florida subspecies (T. manatus latirostris) [6,[15][16][17][18][19][20][21][22][23][24][25]. However, this has not been ascertained for Antillean manatees inhabiting the Greater Antilles.…”