|
|
Cantanhede, A. M.; Silva, Vera Maria Ferreira da; Farias, I. P.; Hrbek, T.; Lazzarini, Stella Maris; Alves-Gomes, J.
(detail)
|
| |
|
2005 |
Phylogeography and population genetics of the endangered Amazonian manatee, Trichechus inunguis, Natterer, 1883 (Mammalia, Sirenia).
Molec. Ecol. 14(2): 401-413. doi.org/10.1111/j.1365-294X.2004.02413.x
|
|
|
Amaral, Rodrigo de Souza; Rosas, Fernando César Weber; Viau, Priscilla; Nichi, Marcilio; Silva, Vera Maria Ferreira da; Oliveira, Cláudio Alvarenga
(detail)
|
| |
|
2011 |
Monitoring salivary testosterone concentrations from captive Amazonian manatees (Trichechus inunguis): Is there seasonal pattern?
Reproduction, Fertility and Development 23(1): 181-181. DOI:10.1071/RDv23n1Ab156. Dec. 2010.
–ABSTRACT: Seasonality of reproduction in many nondomestic animal species appears to represent an accommodation to environmental variables, as food availability, in which influence reproductive success. Males can show a decrease of testicular size, sperm concentration, and serum concentration of testosterone because of food restriction. The Amazonian manatee (Trichechus inunguis, Mammalia: Sirenia) is a threatened aquatic mammal, endemic of the Amazon basin (South America), and is the only sirenian that occurs exclusively in fresh water. Although information is lacking about the reproductive endocrinology of free-ranging T. inunguis, they are considered seasonal breeders, with copulation and births occurring between December and July, coinciding with the increase in Amazon basin water levels and the period of most availability of food for the species (Best 1982 Biotropica 14, 76–78). Salivary steroid measurement is a noninvasive way to monitor steroid concentration, which is well correlated with the level of steroids in the serum. The aim of this study was to verify if testosterone concentrations of male T. inunguis kept in captivity, without variation of food availability, show a seasonal pattern. We used 4 adult male Amazonian manatees kept in captivity in the Laboratory of Aquatic Mammals of the National Institute of Amazonian Research–LMA/INPA, Brazil. They were fed all year with paragrass and vegetables, at not less than 8% of body weight per day. For sample collection, the pool was drained and saliva was collected from mouth mucosa using a metal spoon. Samples were collected weekly for 12 weeks in 2 periods (March–June and September–November). Salivary testosterone was measured by RIA for total testosterone using an adapted protocol previously validated for the species (Amaral et al. 2009 J. Zoo Wildl. Med. 40, 458–465) The data were analysed in a 3 × 2 factorial design, where the factors were month (each 4 weeks = 1 month) and period, using GLM test for repeated-measures. The means of salivary androgen levels were 28.80 ± 18.56 pg mL–1 and 30.77 ± 16.76 pg mL–1 for first and second periods, respectively. There were no significant main effects of month (P = 0.454), period (P = 0.607), or interaction between factors (P = 0.635). These results suggest that captive male Amazonian manatees apparently do not show reproductive seasonality. However, it is recommended to verify the existence of variation in testicular size and sperm concentration. This finding is important information for the future reproductive management of captive Amazonian manatee.
|
|
|
Drummond de Mello, Daniela Magalhães; Silva, Vera Maria Ferreira da; Rosas, Fernando César Weber
(detail)
|
| |
|
2011 |
Serum biochemical analytes in captive Amazonian manatees (Trichechus inunguis).
Veterinary Clinical Pathology 40(1): 74-77. 1 tab. DOI:10.1111/j.1939-165X.2011.00297.x March 2011.
–ABSTRACT: Background: Establishment of reference values for serum biochemical analytes is important for monitoring health and physiological status of captive animals.
Objective: The purpose of this study was to measure and report ranges for serum biochemical analytes in Amazonian manatees (Trichechus inunguis).
Methods: Blood samples were collected from 24 healthy captive Amazonian manatees that comprised a mixture of adults, subadults, and calves and males and females; serum analytes were measured and analyzed using a dry reagent bench-top chemical analyzer. Comparisons were made between sexes and with previously published values of closely related species.
Results: Medians and ranges (minimum–maximum) of values for the analytes were: lactate dehydrogenase (LDH), 151 (111–278) U/L (n=20); creatine kinase, 144 (76–315) U/L (n=11); alanine aminotransferase, 10 (2–28) U/L (n=18); aspartate aminotransferase, 14 (5–28) U/L (n=21); ?-glutamyltransferase, 47 (36–73) U/L (n=21); amylase, 1428 (1010–1874) U/L (n=21); alkaline phosphatase, 73 (36–141) U/L (n=19); total protein, 6.8 (6.2–8.0) g/dL (n=24); albumin, 3.3 (2.6–4.1) g/dL (n=21); cholesterol, 188 (101–399) mg/dL (n=21); triglycerides, 126 (60–236) mg/dL (n=21); glucose, 47 (22–69) mg/dL (n=21); urea, 43 (21–69) mg/dL (n=21); uric acid, 1.1 (0.5–1.8) mg/dL (n=22); creatinine, 2.2 (1.5–3.3) mg/dL (n=22); total bilirubin, 0.2 (0.2–2.0) mg/dL (n=21); calcium, 12.7 (10.2–18.6) mg/dL (n=24); iron, 282 (207–457) ?g/dL (n=13); and magnesium, 6.9 (4.3–8.9) mg/dL (n=20). With the exception of LDH, no differences were observed between sexes.
Conclusions: The ranges obtained in this study provide important preliminary estimates for concentrations and activities of serum analytes in Amazonian manatees until a larger reference interval study can be conducted.
|
|
|
|
Kikuchi, Mumi; Silva, Vera Maria Ferreira da; Rosas, Fernando César Weber; Souza, Diogo; Miyazaki, Nobuyuki
(detail)
|
| |
|
2012 |
The implications of turning behaviour performed by Amazonian manatees after release into the wild.
Journal of Ethology 30(1): 187-190. 1 tab. 2 figs. DOI:10.1007/s10164-011-0290-0. Jan. 2012.
–ABSTRACT: Sirenians have dichromatic colour vision and tactile hairs but have not developed underwater echolocation. Amazonian manatees (Trichechus inunguis) live in turbid water and it has been unclear how they understand their surroundings. In this study, we recorded the 3D movements of two captive-raised Amazonian manatees. The results revealed that the manatees always swam in a circular pattern. Both animals used slower, narrower turning motions as they approached the flooded forests, which are abundant in aquatic vegetation. Therefore, we suggest that these two manatees swam in a circular pattern to detect all directions of their surroundings especially using sensitive facial bristles.
|
|
|
Amaral, Rodrigo de Souza; Rosas, Fernando Cesar Weber; Silva, Vera Maria Ferreira da; Nichi, Marcilio; Oliveira, Cláudio Alvarenga
(detail)
|
| |
|
2013 |
Endocrine monitoring of the ovarian cycle in captive female Amazonian manatees (Trichechus inunguis).
Animal Reproduction Science 142(1-2): 84-88. 1 tab. 1 fig. Nov. 2013.
–ABSTRACT: The Amazonian manatee (Trichechus inunguis; Mammalia: Sirenia), a threatened aquatic mammal endemic to the Amazon basin, is the only sirenian that lives exclusively in fresh water. Information about the reproductive endocrinology of the Amazonian manatee is scarce; therefore, the aim of this study was to monitor salivary progesterone and estradiol patterns during the ovarian cycle in T. inunguis. Salivary samples were collected daily during a 12-week period of two consecutive years from two captive adult females. The salivary estradiol and progesterone were measured by enzyme immunoassay. The results were analyzed in an iterative process of excluding values that were higher than the mean plus 2 standard deviations until the basal values were determined. The interval between two peaks of salivary estradiol followed by a rise of progesterone was considered as one complete cycle for the calculation of the cycle length. We observed only three complete cycles in all samples analyzed. The cycle length ranged from 42 to 48 days (mean of 44.67 days). We also observed two distinct salivary estradiol peaks during all cycles analyzed, with the first peak occurring before the rise in salivary progesterone and the second occurred followed by a return to basal progesterone levels. This is the first in-depth study of the ovarian cycle in Amazonian manatees. Our results demonstrate that salivary samples can be a useful tool in the endocrine monitoring of this species and suggest that T. inunguis shows a peculiar hormonal pattern during the ovarian cycle, a finding that may have physiological and ecological significance in the reproductive strategy of these animals.
|
|
|
Barbosa, Paula de Sousa; Silva, Vera Maria Ferreira da; Pereira Junior, Geraldo
(detail)
|
| |
|
2013 |
Tempo de passagem de duas dietas no trato gastrointestinal do peixe-boi da Amazônia Trichechus inunguis (Natterer, 1883) em cativeiro.
Acta Amazonica 43(3): 365-370. 2 tabs.
–Engl. summ.
ABSTRACT: The objective of this study was to determine the transit time of two diets in the digestive tract of the Amazonian manatee in captivity. We tested separately two different diets: one composed exclusively of grass of the genus Brachiaria (experimental diet - ED- A 1) and the other composed of grass Brachiaria added with small portions of extruded pellets for horses (experimental diet ED- A 2). Two healthy adult manatees were selected and isolated from the rest and underwent a period of food acclimation with the experimental diets for 15 days. After this period, the experimental diet was marked with a plastic colored tape of 10-cm length and given to the animals. The manatees were monitored at intervals of 1 hour and all fecal material was collected until recovery of the markers. The mean transit time of ED – A1 was 123h57min , about 5.16 days and ED – A 2 was 125h04min or 5.21 days. There was no statistical difference (P <0.05) between the transit time of the two diets provided. The transit time observed (approximately 5 days) has also been reported by other authors for this species and is considered a strategy to increase the absorption time of food nutrients. Despite the small sample size, the results suggest that the use of pellets in the diet of the Amazonian manatee did not affect the transit time of the grass. Therefore, it is reasonable to believe that the introduction of concentrated food (pellets) does not affect the efficiency of the animal to digest and absorb food properly.
|
|
|
Carmo, Talita Laurie Lustosa do; Amaral, Rodrigo de Souza; Rosas, Fernando Cesar Weber; D'Affonsêca Neto, José Anselmo; Reisfeld, Laura; Silva, Vera Maria Ferreira da
(detail)
|
| |
|
2013 |
Changes in the blood parameters of the Amazonian manatee (Trichechus inunguis) after long-distance transportation.
Acta Scientiarum, Biological Sciences 35(4): 591-594. 1 tab. Doi: 10.4025/actascibiolsci.v35i4.20081 Oct.-Dec. 2013.
–Portuguese summ.
ABSTRACT: In this study we report the hematological, biochemical and hormonal parameters in a juvenile male Amazonian manatee measured before transport, immediately after transport, and during adaptation to a new facility. The animal was transported from Manaus, Amazonas State, Brazil, to São Paulo, São Paulo State, Brazil, (2,733 km) within 6 hours. Among all blood parameters analyzed, we observed obvious neutrophilia, lymphopenia, and increases in the neutrophil/lymphocyte ratio and serum glucose and aspartate aminotransferase (AST) levels, but these parameters subsequently returned to normal. These results suggest that transport and changes in the environment are temporary stressful events for Amazonian manatees. We, therefore, recommend monitoring the hematological and biochemical parameters before and after translocation to minimize the effects of handling stressors in this species.
|
|
|
Franzini, André M.; Castelblanco-Martínez, Delma Nataly; Rosas, Fernando César Weber; Silva, Vera Maria Ferreira da
(detail)
|
| |
|
2013 |
What do local people know about Amazonian manatees? Traditional ecological knowledge of Trichechus inunguis in the Oil Province of Urucu, AM, Brazil.
Natureza & Conservação (Brazilian Journal of Nature Conservation) 11(1): 75-80. 1 tab. 3 figs. Supplementary material at abeco.org.br. July 2013.
–ABSTRACT: During 2005-2007, a series of interviews were carried out with the riverside populations of the Oil Province of Urucu (AM, Brasil). The main goal of this work was to characterize the knowledge of the inhabitants of this area regarding the Amazonian manatee (Trichechus inunguis) (listed as Vulnerable on the IUCN Red List). Interviews were conducted with 74 local inhabitants from 33 communities. Between 2004 and 2007, 20 poached or entangled Amazonian manatees were reported in the area. Poaching with harpoon is the principal cause of mortality, but manatees are also incidentally caught in fishing nets. Interviewers described details of manatee hunting techniques in the area. The trade of manatee meat, although currently forbidden by Brazilian laws, still occurs in the area. Data obtained from the interviews suggest a dietary preference of the manatee for at least 29 species of aquatic and semi-aquatic plants. The interviewed fishermen showed a sound knowledge of Amazonian manatee biology and behavior. This information may be important to assist future conservation plans in the Amazon.
|
|
|
Rodrigues, Fernanda Rosa; Silva, Vera Maria Ferreira da; Marques Barcellos, José Fernando
(detail)
|
| |
|
2014 |
The mammary glands of the Amazonian manatee, Trichechus inunguis (Mammalia: Sirenia): morphological characteristics and microscopic anatomy.
Anat. Rec. 297(8): 1532-1535. 1 tab. 2 figs. DOI: 10.1002/ar.22956. Publ. online June 12, 2014.
–ABSTRACT: The mammaries from carcasses of two female Amazonian manatees were examined. Trichechus inunguis possesses two axillary mammaries beneath the pectoral fins, one on each side of the body. Each papilla mammae has a small hole on its apex--the ostium papillare. The mammaries are covered by a stratified squamous keratinized epithelium. The epithelium of the mammary ducts became thinner more deeply in the tissue and varied from stratified to simple cuboidal. There was no evidence of glandular activity or secretion into the ducts of the mammary glands.
|
|
|
Crema, Luciana Carvalho; Silva, Vera Maria Ferreira da; Botta, Silvina; Trumbore, Susan; Piedade, Maria Teresa Fernandez
(detail)
|
| |
|
2019 |
Does water type influence diet composition in Amazonian manatee (Trichechus inunguis)? A case study comparing black and clearwater rivers.
Hydrobiologia 835(1): 1-19. doi.org/10.1007/s10750-019-3900-4 June 2019 (publ. online Feb. 12, 2019).
–ABSTRACT: We assessed the feeding habits of the Amazonian manatee inhabiting blackwater (Negro River) and clearwater (Tapajós River) igapós (floodplains) using ?13C and ?15N of dentin and bone collagen from different ontogenetic classes (nursing calves, juveniles, and adults). Within an individual, the dentine ?13C and ?15N values did not vary with tooth position. Bones were more depleted in 13C and 15N compared to teeth, and the ?13C and ?15N in bone differed among classes. Food sources had ?13C values typical of algae, plants of C3 or C4 photosynthetic pathways. Mixing models showed that lactating females (inferred by isotopic values from nursing calves) had higher proportional consumption of C4 plants, while, for other adults, C3 plants were more frequent in the diet of manatees from both rivers. Juveniles had a mixed diet of C3 pants and C4 plants. We hypothesize the C4 plants signal of calves results from female movements to the floodplains of nearby whitewater rivers (várzeas), where C4 plants are abundant. Individuals from Tapajós may be more resident, as C3 plants and C4 plants are available during the flood pulse. Results demonstrate that manatee diets vary with ontogenetic classes and water typology. Preservation of habitats (igapó/várzea) is therefore required for the survival of Amazonian manatees.
|
|
|
Silva, Vera Maria Ferreira da; Souza, Diogo Alexandre de; d'Affonseca, Anselmo; Amaral, Rodrigo de Souza; Romero, Ricardo
(detail)
|
| |
|
2019 |
Mamíferos Aquáticos da Amazônia. Aquatic mammals of the Amazon.
Manaus, Editora INPA: 1-120. Illus.
–Text in both Portuguese and English. Richly illustrated history and description of the Aquatic Mammals Program at the National Institute of Amazonian Research (INPA), Manaus, Brazil. Preface by D. Domning, pp. 6-7. The Amazonian Manatee Project is covered mainly on pp. 32-41, but numerous other photographs of T. inunguis are scattered throughout.
|
|
Bibliography and Index of the Sirenia and Desmostylia 