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Gordon B. Bauer - One of the best experts on this subject based on the ideXlab platform.

  • Behavioral lateralization in the Florida manatee (Trichechus manatus latirostris)
    International Journal of Comparative Psychology, 2016
    Co-Authors: Kara Tyler-julian, Kate M Chapman, Candice Frances, Gordon B. Bauer
    Abstract:

    Author(s): Tyler-Julian, Kara; Chapman, Kate M; Frances, Candice; Bauer, Gordon B | Abstract: We examined side preferences in the Florida manatee (Trichechus manatus latirostris) through observations of limb use (right and left flipper) in 123 wild and 16 captive individuals. We also analyzed archival data on wild manatees to develop an index of boat-caused body scars to determine lateralization of evasive action. Wild and captive manatees displayed flipper lateralization at the individual, but not the population level for several behaviors including substrate touches, sculling, and feeding. In contrast, manatees were lateralized at the population level for boat-scar biases with more manatees showing a left scar bias (45%) versus right (34%) or dorsal (21%).

  • tactile discrimination of textures by florida manatees Trichechus manatus latirostris
    Marine Mammal Science, 2012
    Co-Authors: Gordon B. Bauer, Joseph C Gaspard, Debborah E Colbert, Jennifer B Leach, Sarah A Stamper, David A Mann, Roger L. Reep
    Abstract:

    Two male Florida manatees (Trichechus manatus latirostris) demonstrated sensitive tactile discrimination in a two-alternative forced choice task, using a modified staircase method. Stimuli were acrylic plates with vertical gratings of ridges and grooves. The standard stimulus, present on every trial, had 2 mm gratings and the comparison stimuli had wider gratings. The blindfolded subjects were trained to demonstrate discrimination by pressing the target with wider gratings. Discrimination thresholds (75% correct) for the subjects were 2.05 mm and 2.15 mm, corresponding to Weber fractions of 0.025 and 0.075, respectively. These results indicate thresholds on similar stimuli comparable to humans (index finger tasks) and better than harbor seals, Phoca vitulina, and the closely related Antillean manatee, Trichechus manatus manatus. Memory for the tactile task was quite stable for both subjects, over 2 yr in the case of one of the subjects. Video analysis of responses indicated that bristle-like hairs, perioral bristles, and skin on the oral disk were involved in the discrimination response.

  • temporal resolution of the florida manatee Trichechus manatus latirostris auditory system
    Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 2005
    Co-Authors: Mandy L H Cook, Joseph C Gaspard, Debborah E Colbert, Brandon M Casper, Gordon B. Bauer, Roger L. Reep, David A Mann
    Abstract:

    Auditory evoked potential (AEP) measurements of two Florida manatees (Trichechus manatus latirostris) were measured in response to amplitude modulated tones. The AEP measurements showed weak responses to test stimuli from 4 kHz to 40 kHz. The manatee modulation rate transfer function (MRTF) is maximally sensitive to 150 and 600 Hz amplitude modulation (AM) rates. The 600 Hz AM rate is midway between the AM sensitivities of terrestrial mammals (chinchillas, gerbils, and humans) (80–150 Hz) and dolphins (1,000–1,200 Hz). Audiograms estimated from the input–output functions of the EPs greatly underestimate behavioral hearing thresholds measured in two other manatees. This underestimation is probably due to the electrodes being located several centimeters from the brain.

  • temporal resolution of the florida manatee Trichechus manatus latirostris auditory system
    Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 2005
    Co-Authors: Mandy L H Cook, Joseph C Gaspard, Debborah E Colbert, Brandon M Casper, Gordon B. Bauer, Roger L. Reep, David A Mann
    Abstract:

    Auditory evoked potential (AEP) measurements of two Florida manatees (Trichechus manatus latirostris) were measured in response to amplitude modulated tones. The AEP measurements showed weak responses to test stimuli from 4 kHz to 40 kHz. The manatee modulation rate transfer function (MRTF) is maximally sensitive to 150 and 600 Hz amplitude modulation (AM) rates. The 600 Hz AM rate is midway between the AM sensitivities of terrestrial mammals (chinchillas, gerbils, and humans) (80–150 Hz) and dolphins (1,000–1,200 Hz). Audiograms estimated from the input–output functions of the EPs greatly underestimate behavioral hearing thresholds measured in two other manatees. This underestimation is probably due to the electrodes being located several centimeters from the brain.

  • underwater visual acuity of florida manatees Trichechus manatus latirostris
    International Journal of Comparative Psychology, 2003
    Co-Authors: Gordon B. Bauer, Joseph C Gaspard, Debborah E Colbert, Brandie Littlefield, Wendi Fellner
    Abstract:

    In Experiment 1 underwater visual acuity was assessed in two Florida manatees, Trichechus manatus latirostris, using grating stimuli in three conditions: Vertical gratings presented in freshwater, vertical gratings in saltwater, and horizontal gratings in saltwater. All stimuli were tested in a free-swimming format from a minimum distance of one meter. Substantial differences were found between the two subjects. One subject's minimum angles of resolution (MAR) were 56 min for vertical stimuli in freshwater, 38 min for vertical stimuli in saltwater, and 24 min for horizontal grating stimuli in salt- water. When only trials under brightest light conditions were analyzed, MARs improved for vertical stimuli to 24 min in freshwater and 21 min in saltwater. No improvement was found for horizontal stimuli with brighter light conditions. The MARs of the second subject measured over a degree for all test conditions. In Experiment 2 only the first subject was tested from a closer viewing distance. He showed no improvement when allowed to approach targets to within 30 cm. The limited resolution of both subjects and absence of increased acuity at closer distances in one suggests that manatees use vision for intermediate or longer distance inspection of large objects. The disparity in visual resolu- tion between subjects has possible implications for variability in acuity within the species.

David A Mann - One of the best experts on this subject based on the ideXlab platform.

  • tactile discrimination of textures by florida manatees Trichechus manatus latirostris
    Marine Mammal Science, 2012
    Co-Authors: Gordon B. Bauer, Joseph C Gaspard, Debborah E Colbert, Jennifer B Leach, Sarah A Stamper, David A Mann, Roger L. Reep
    Abstract:

    Two male Florida manatees (Trichechus manatus latirostris) demonstrated sensitive tactile discrimination in a two-alternative forced choice task, using a modified staircase method. Stimuli were acrylic plates with vertical gratings of ridges and grooves. The standard stimulus, present on every trial, had 2 mm gratings and the comparison stimuli had wider gratings. The blindfolded subjects were trained to demonstrate discrimination by pressing the target with wider gratings. Discrimination thresholds (75% correct) for the subjects were 2.05 mm and 2.15 mm, corresponding to Weber fractions of 0.025 and 0.075, respectively. These results indicate thresholds on similar stimuli comparable to humans (index finger tasks) and better than harbor seals, Phoca vitulina, and the closely related Antillean manatee, Trichechus manatus manatus. Memory for the tactile task was quite stable for both subjects, over 2 yr in the case of one of the subjects. Video analysis of responses indicated that bristle-like hairs, perioral bristles, and skin on the oral disk were involved in the discrimination response.

  • temporal resolution of the florida manatee Trichechus manatus latirostris auditory system
    Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 2005
    Co-Authors: Mandy L H Cook, Joseph C Gaspard, Debborah E Colbert, Brandon M Casper, Gordon B. Bauer, Roger L. Reep, David A Mann
    Abstract:

    Auditory evoked potential (AEP) measurements of two Florida manatees (Trichechus manatus latirostris) were measured in response to amplitude modulated tones. The AEP measurements showed weak responses to test stimuli from 4 kHz to 40 kHz. The manatee modulation rate transfer function (MRTF) is maximally sensitive to 150 and 600 Hz amplitude modulation (AM) rates. The 600 Hz AM rate is midway between the AM sensitivities of terrestrial mammals (chinchillas, gerbils, and humans) (80–150 Hz) and dolphins (1,000–1,200 Hz). Audiograms estimated from the input–output functions of the EPs greatly underestimate behavioral hearing thresholds measured in two other manatees. This underestimation is probably due to the electrodes being located several centimeters from the brain.

  • temporal resolution of the florida manatee Trichechus manatus latirostris auditory system
    Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 2005
    Co-Authors: Mandy L H Cook, Joseph C Gaspard, Debborah E Colbert, Brandon M Casper, Gordon B. Bauer, Roger L. Reep, David A Mann
    Abstract:

    Auditory evoked potential (AEP) measurements of two Florida manatees (Trichechus manatus latirostris) were measured in response to amplitude modulated tones. The AEP measurements showed weak responses to test stimuli from 4 kHz to 40 kHz. The manatee modulation rate transfer function (MRTF) is maximally sensitive to 150 and 600 Hz amplitude modulation (AM) rates. The 600 Hz AM rate is midway between the AM sensitivities of terrestrial mammals (chinchillas, gerbils, and humans) (80–150 Hz) and dolphins (1,000–1,200 Hz). Audiograms estimated from the input–output functions of the EPs greatly underestimate behavioral hearing thresholds measured in two other manatees. This underestimation is probably due to the electrodes being located several centimeters from the brain.

  • intraspecific and geographic variation of west indian manatee Trichechus manatus spp vocalizations l
    Journal of the Acoustical Society of America, 2003
    Co-Authors: Douglas P Nowacek, Stephanie M Nowacek, Brandon M Casper, Randall S Wells, David A Mann
    Abstract:

    Recordings of manatee (Trichechus manatus spp.) vocalizations were made in Florida and Belize to quantify both intraspecific and geographic variation. Manatee vocalizations were relatively stereotypical in that they were short tonal harmonic complexes with small frequency modulations at the beginning and end. Vocalizations ranged from almost pure tones to broader-band tones that had a raspy quality. The loudest frequency was typically the second or third harmonic, with average received levels of the peak frequency of about 100 dB re 1 μPa. Signal parameters measured from these calls showed the manatees from Belize and Florida have overlapping distributions of sound duration, peak frequency, harmonic spacing, and signal intensity, indicating no obvious distinguishing characteristics between these isolated populations.

Roger L. Reep - One of the best experts on this subject based on the ideXlab platform.

  • thromboelastography in wild florida manatees Trichechus manatus latirostris
    Veterinary Clinical Pathology, 2018
    Co-Authors: Ashley Barratclough, Ruth Francis Floyd, Ray L. Ball, Roger L. Reep, Bobbi J. Conner
    Abstract:

    BACKGROUND: Thromboelastography (TEG) provides a comprehensive evaluation of blood clot formation. This test can be used to identify abnormalities in coagulation by assessing multiple aspects of the clotting cascade, including the speed of clot initiation and formation, clot strength, and ultimately fibrinolysis. Thromboembolic disease has been hypothesized to play a role in the pathophysiology of cold stress syndrome (CSS), an important cause of mortality in the threatened Florida manatee (Trichechus manatus latirostris). OBJECTIVES: The objective of this study was to establish thromboelastography RIs using the TEG 5000 with citrated whole blood samples and kaolin activation in wild, healthy manatees. METHODS: In December 2014 and January 2015, 29 wild manatees (17 male and 12 female) were blood sampled as part of the annual wild manatee health assessments organized by United States Geological Survey (USGS). TEG was performed using citrated kaolin-activated samples. RESULTS: The samples were obtained from manatees caught in Crystal River, Citrus County, and used to identify the mean ± SD of normal TEG parameters: R = reaction time 2.1 minutes (0.8), K = clot formation time 0.8 min (0), α angle = 83.1° (2), MA = maximum amplitude 75 mm (7.6), and LY30 = clot lysis 0.41% (0.68). No significant differences were found between manatee size, sex, or time between sampling and running the test. CONCLUSIONS: Manatee TEG parameters demonstrate a relatively hypercoagulable condition when compared to other mammals. This information will facilitate detection of changes in hemostasis during injury and disease and provide a valuable reference range.

  • Identifying coagulopathies in the pathophysiology of cold stress syndrome in the Florida manatee Trichechus manatus latirostris
    Diseases of Aquatic Organisms, 2017
    Co-Authors: Ashley Barratclough, Bobbi J. Conner, Alyssa Pontes Stablein, Trevor J. Gerlach, Ray L. Ball, Roger L. Reep, Marjory B. Brooks, Ruth Francis Floyd
    Abstract:

    : Cold stress syndrome (CSS) in the Florida manatee Trichechus manatus latirostris has been defined as morbidity and mortality resulting from prolonged exposure to water temperatures

  • golgi analysis of neuron morphology in the presumptive somatosensory cortex and visual cortex of the florida manatee Trichechus manatus latirostris
    Brain Behavior and Evolution, 2016
    Co-Authors: Laura D Reyes, Tessa Harland, Roger L. Reep, Chet C. Sherwood, Bob Jacobs
    Abstract:

    The current study investigates neuron morphology in presumptive primary somatosensory (S1) and primary visual (V1) cortices of the Florida manatee (Trichechus manatus latirostris) a

  • tactile discrimination of textures by florida manatees Trichechus manatus latirostris
    Marine Mammal Science, 2012
    Co-Authors: Gordon B. Bauer, Joseph C Gaspard, Debborah E Colbert, Jennifer B Leach, Sarah A Stamper, David A Mann, Roger L. Reep
    Abstract:

    Two male Florida manatees (Trichechus manatus latirostris) demonstrated sensitive tactile discrimination in a two-alternative forced choice task, using a modified staircase method. Stimuli were acrylic plates with vertical gratings of ridges and grooves. The standard stimulus, present on every trial, had 2 mm gratings and the comparison stimuli had wider gratings. The blindfolded subjects were trained to demonstrate discrimination by pressing the target with wider gratings. Discrimination thresholds (75% correct) for the subjects were 2.05 mm and 2.15 mm, corresponding to Weber fractions of 0.025 and 0.075, respectively. These results indicate thresholds on similar stimuli comparable to humans (index finger tasks) and better than harbor seals, Phoca vitulina, and the closely related Antillean manatee, Trichechus manatus manatus. Memory for the tactile task was quite stable for both subjects, over 2 yr in the case of one of the subjects. Video analysis of responses indicated that bristle-like hairs, perioral bristles, and skin on the oral disk were involved in the discrimination response.

  • topographical organization of the facial motor nucleus in florida manatees Trichechus manatus latirostris
    Brain Behavior and Evolution, 2007
    Co-Authors: Christopher D. Marshall, Susan D Vaughn, Diana K Sarko, Roger L. Reep
    Abstract:

    Florida manatees (Trichechus manatus latirostris) possess modified vibrissae that are used in conjunction with specialized perioral musculature to manipulate vegetation for ingestio

Sentiel A Rommel - One of the best experts on this subject based on the ideXlab platform.

  • Nephrolithiasis and Pyelonephritis in Two West Indian Manatees (Trichechus manatus spp.)
    Journal of Wildlife Diseases, 2008
    Co-Authors: Martha Keller, Sentiel A Rommel, José L. Moliner, Grettys Vásquez, Danilo Cruz, Orestes Bello, Alex M. Costidis, Maron B. Calderwood Mays, Scott Gearhart
    Abstract:

    Two West Indian manatees (Trichechus manatus spp.) were reported with severe emaciation. One animal was a Florida manatee from the Everglades; the other was an Antillean manatee from Cuba. On necropsy, both animals had nephrolithiasis, pyelonephritis, and moderate to severe renomegaly. Histopathology revealed multifocal to diffuse pyelonephritis, interstitial nephritis, and nephrocalcinosis. The stones were analyzed and consisted primarily of calcium carbonate. Serum chemistry values for the Florida animal revealed no renal abnormalities. The mechanism of calculus formation remains unclear in manatees. In horses, another hindgut fermenter, the most common urolith is also calcium carbonate. Urinalyses performed on manatees are very similar to those of horses (i.e., alkaline urine, low specific gravity, and calcium carbonate crystals). Formation of uroliths in manatees may have a pathogenesis similar to equine urolithiasis.

  • ct scans and 3d reconstructions of florida manatee Trichechus manatus latirostris heads and ear bones
    Hearing Research, 2007
    Co-Authors: Sentiel A Rommel, Marie E Chapla, Douglas P Nowacek, Valerie M Sadler
    Abstract:

    Abstract The auditory anatomy of the Florida manatee (Trichechus manatus latirostris) was investigated using computerized tomography (CT), three-dimensional reconstructions, and traditional dissection of heads removed during necropsy. The densities (kg/m3) of the soft tissues of the head were measured directly using the displacement method and those of the soft tissues and bone were calculated from CT measurements (Hounsfield units). The manatee’s fatty tissue was significantly less dense than the other soft tissues within the head (p

  • ct scans and 3d reconstructions of florida manatee Trichechus manatus latirostris heads and ear bones
    Hearing Research, 2007
    Co-Authors: Marie E Chapla, Sentiel A Rommel, Douglas P Nowacek, Valerie M Sadler
    Abstract:

    The auditory anatomy of the Florida manatee (Trichechus manatus latirostris) was investigated using computerized tomography (CT), three-dimensional reconstructions, and traditional dissection of heads removed during necropsy. The densities (kg/m3) of the soft tissues of the head were measured directly using the displacement method and those of the soft tissues and bone were calculated from CT measurements (Hounsfield units). The manatee's fatty tissue was significantly less dense than the other soft tissues within the head (p<0.05). The squamosal bone was significantly less dense than the other bones of the head (p<0.05). Measurements of the ear bones (tympanic, periotic, malleus, incus, and stapes) collected during dissection revealed that the ossicular chain was overly massive for the mass of the tympanoperiotic complex.

  • pathologic findings in florida manatees Trichechus manatus latirostris
    Aquatic Mammals, 2004
    Co-Authors: Gregory D Bossart, Jessica D. Lightsey, Sentiel A Rommel, Roberta A. Meisner, Rene A Varela, R H Defran
    Abstract:

    This report describes pathologic findings associated with mortality in Florida manatees (Trichechus manatus latirostris) (n = 68) between January 1996 and January 2004. The most frequent causes of death among these Florida manatees were trauma (47%), cold stress syndrome (CSS) (18%), inflammatory/infectious disease (12%), and suspected brevetoxicosis (9%). There were few perinatal deaths (7%). Probably all deaths due to trauma, as well as some, and perhaps many, cases of CSS, may be regarded as anthropogenic, reinforcing the need for conservation and management strategies to mitigate these impacts on this endangered species. Cause of death was determinable in a high proportion (94%) of sample cases, demonstrating the importance of performing timely gross and microscopic necropsy examinations on marine mammals.

Valerie M Sadler - One of the best experts on this subject based on the ideXlab platform.

  • conservative management of pneumothorax and pneumoperitoneum in two florida manatees Trichechus manatus latirostris
    Journal of Zoo and Wildlife Medicine, 2013
    Co-Authors: Trevor J. Gerlach, Valerie M Sadler, Ray L. Ball
    Abstract:

    Abstract:  Two distressed Florida manatees (Trichechus manatus latirostris) were reported to the Florida Fish and Wildlife Conservation Commission. The first animal was determined to be an abandoned, emaciated calf. The second animal was a nursing calf that had sustained watercraft-related trauma. Both animals were captured and transported to Tampa's Lowry Park Zoo, where diagnostic evaluations, including physical examinations, blood work, computed tomography (CT), and radiographs were performed. Radiograph and CT scans identified the presence of free air within the pleural and abdominal cavities of both animals. Based on the lack of substantial findings in the first animal and a rapid resolution of clinical signs in the second animal, both animals were managed conservatively. This report documents simultaneous pneumothorax and pneumoperitoneum, the associated clinical and diagnostic findings, and conservative medical management of these conditions in the Florida manatee.

  • ct scans and 3d reconstructions of florida manatee Trichechus manatus latirostris heads and ear bones
    Hearing Research, 2007
    Co-Authors: Sentiel A Rommel, Marie E Chapla, Douglas P Nowacek, Valerie M Sadler
    Abstract:

    Abstract The auditory anatomy of the Florida manatee (Trichechus manatus latirostris) was investigated using computerized tomography (CT), three-dimensional reconstructions, and traditional dissection of heads removed during necropsy. The densities (kg/m3) of the soft tissues of the head were measured directly using the displacement method and those of the soft tissues and bone were calculated from CT measurements (Hounsfield units). The manatee’s fatty tissue was significantly less dense than the other soft tissues within the head (p

  • ct scans and 3d reconstructions of florida manatee Trichechus manatus latirostris heads and ear bones
    Hearing Research, 2007
    Co-Authors: Marie E Chapla, Sentiel A Rommel, Douglas P Nowacek, Valerie M Sadler
    Abstract:

    The auditory anatomy of the Florida manatee (Trichechus manatus latirostris) was investigated using computerized tomography (CT), three-dimensional reconstructions, and traditional dissection of heads removed during necropsy. The densities (kg/m3) of the soft tissues of the head were measured directly using the displacement method and those of the soft tissues and bone were calculated from CT measurements (Hounsfield units). The manatee's fatty tissue was significantly less dense than the other soft tissues within the head (p<0.05). The squamosal bone was significantly less dense than the other bones of the head (p<0.05). Measurements of the ear bones (tympanic, periotic, malleus, incus, and stapes) collected during dissection revealed that the ossicular chain was overly massive for the mass of the tympanoperiotic complex.