a third report of "golf ball disease" in an amazon river dolphin (inia geoffrensis) associated with streptococcus amazon river dolphin (inia geoffrensis) developed a dermatologic syndrome characterized by the occurrence of slow-growing, nodular, s.c. abscesses. initial biopsies, cultures, and cytologic analysis of needle aspirates from the abscesses indicated steatitis with probable secondary, gram-negative bacterial infection. treatment with dietary vitamin e supplement and broad-spectrum antibiotics yielded minimal improvement. subsequent cultures revealed streptococcus iniae in addition to several gra ...200314582795
placentation in dolphins from the amazon river basin: the boto, inia geoffrensis, and the tucuxi, sotalia fluviatilis.a recent reassessment of the phylogenetic affinities of cetaceans makes it timely to compare their placentation with that of the artiodactyls. we studied the placentae of two sympatric species of dolphin from the amazon river basin, representing two distinct families. the umbilical cord branched to supply a bilobed allantoic sac. small blood vessels and smooth muscle bundles were found within the stroma of the cord. foci of squamous metaplasia occurred in the allanto-amnion and allantochorion. t ...200717597550
object carrying as socio-sexual display in an aquatic river dolphins or botos (inia geoffrensis blainville) were observed carrying objects in 221 social groups over a 3-year study period. sticks, branches and clumps of grass were taken from the water surface and often repeatedly thrashed or thrown. lumps of hard clay were collected from the river bed and held in the mouth while the carrier rose slowly above the surface and submerged again. carriers were predominantly adult males and less often subadult males. adult females and young dolphins ...200818364306
seroprevalence of toxoplasma gondii in free-living amazon river dolphins (inia geoffrensis) from central amazon, brazil.toxoplasma gondii is an important pathogen in aquatic mammals and its presence in these animals may indicate the water contamination of aquatic environment by oocysts. serum samples from 95 free-living amazon river dolphins (inia geoffrensis) from the mamirauá sustainable development reserve (rdsm), tefé, amazonas, central amazon, brazil were tested for t. gondii antibodies using the modified agglutination test (mat). antibodies (mat=25) to t. gondii were found in 82 (86.3%) dolphins with titers ...201121764516
underwater audiogram of a false killer whale (pseudorca crassidens).underwater audiograms are available for only a few odontocete species. a false killer whale (pseudorca crassidens) was trained at sea life park in oahu, hawaii for an underwater hearing test using a go/no-go response paradigm. over a 6-month period, auditory thresholds from 2-115 khz were measured using an up/down staircase psychometric technique. the resulting audiogram showed hearing sensitivities below 64 khz similar to those of belugas (delphinapterus leucas) and atlantic bottlenosed dolphin ...19883183211
functional morphology and symmetry in the odontocete ear complex.odontocete ear complexes or tympanoperiotic complexes (tpcs) were compared for asymmetry. left and right tpcs were collected from one long-beaked common dolphin (delphinus capensis) and one amazon river dolphin (inia geoffrensis). asymmetry was assessed by volumetric comparisons of left and right tpcs and by visual comparison of superimposed models of the right tpc to a reflected mirror image of the left tpc. kolmogorov-smirnov tests were performed to compare the resonant frequencies of the tpcs ...201626610944
perception of local inhabitants regarding the socioeconomic impact of tourism focused on provisioning wild dolphins in novo airão, central amazon, brazil.botos (inia geoffrensis) are currently provisioned for use in tourist attractions in five sites in the brazilian amazon. despite the known negative effects associated with human-wild dolphin interactions, this activity has been regulated and licensed in the anavilhanas national park in novo airão, amazonas state, brazil. we present an updated evaluation of the perception of the local community concerning the possible socioeconomic impacts of this tourism in novo airão. in april 2011, 45 intervie ...201324346803
presumed normal ultrasonographic findings of the testis and epididymis of botos (inia geoffrensis).fifteen live adult male botos, or amazon river dolphins (inia geoffrensis), were examined using ultrasonography during the yearly capture expedition, between october and november 2005, at the mamirauá sustainable development reserve, within the brazilian amazon (3 degrees s, 65 degrees w). all examinations were performed with a sonosite 180 plus ultrasound unit in conjunction with a 2- to 5-mhz multifrequency transducer convex array 180 plus/elite-c60. age and maturity estimates were determined ...201223272345
the antiquity of riverine adaptations in iniidae (cetacea, odontoceti) documented by a humerus from the late miocene of the ituzaingó formation, argentina."river dolphins" are a paraphyletic group of toothed whales (odontoceti) that represent independent secondary invasions of freshwater habitats. different "river dolphin" lineages display suites of convergent morphological specializations that commonly reflect adaptations to riverine and freshwater environments, such as longirostry, reduced orbits, and wide, paddle-like flippers. one lineage, the iniidae, is presently endemic to south america, and includes several extinct neogene taxa along with ...201424585575
when you get what you haven't paid for: molecular identification of "douradinha" fish fillets can help end the illegal use of river dolphins as bait in brazil.the fishery for calophysus macropterus, an amazonian necrophagous catfish, is highly detrimental to river dolphins and caimans, which are deliberately killed for use as bait. in the brazilian amazon, this fishery has increased over the last decade, in spite of the rejection of scavenger fishes by brazilian consumers. it was suspected that c. macropterus fillets were being sold in brazilian markets, disguised as a fictitious fish (the "douradinha"). we collected 62 fillets from "douradinha" and o ...201526245791
neuronal fiber composition of the corpus callosum within some odontocetes.odontocetes (toothed whales) evolved from terrestrial mammals approximately 55 million years ago and have since remained on a unique evolutionary trajectory. this study used formalin-fixed tissue and light microscopy to quantify the size and number of fibers along the corpus callosum of the bottlenose dolphin (n = 8). two other species, the amazon river dolphin (n = 1) and the killer whale (n = 1), were included for comparison. a large amount of variation in the shape and area of the corpus call ...200818493931
acoustic characteristics of biosonar sounds of free-ranging botos (inia geoffrensis) and tucuxis (sotalia fluviatilis) in the negro river, amazon, brazil.odontoceti emit broadband high-frequency clicks on echolocation for orientation or prey detection. in the amazon basin, two odontoceti species, boto (amazon river dolphin, inia geoffrensis) and tucuxi (sotalia fluviatilis), live sympatrically. the acoustic characteristics of the echolocation clicks of free-ranging botos and tucuxis were measured with a hydrophone array consisting of a full-band and an acoustic event recorder (a-tag). the clicks of the two species were short-duration broadband si ...201526328686
interaural intensity and latency difference in the dolphin's auditory system.binaural hearing mechanisms were measured in dolphins (inia geoffrensis) by recording the auditory nerve evoked response from the body surface. the azimuthal position of a sound source at 10-15 degrees from the longitudinal axis elicited interaural intensity disparity up to 20 db and interaural latency difference as large as 250 microseconds. the latter was many times greater than the acoustical interaural time delay. this latency difference seems to be caused by the intensity disparity. the lat ...19911816509
electrophysiological study of interaural sound intensity difference in the dolphin inia geoffrensis.a wave observed in the auditory brainstem responses (abr), sensitive to the side of sound presentation, is described in a dolphin (inia geoffrensis). dependence of the wave threshold on location of the sound source showed that the interaural intensity difference was more than 20 db.19911915778
location of an acoustic window in dolphins.auditory brainstem responses (abr) to sound clicks from sources in different positions were recorded in dolphins inia geoffrensis. the position of the acoustic window was determined by measurement of acoustic delays. the acoustic window was found to lie close to the auditory meatus and the bulla rather than on the lower jaw.19902298282
unihemispheric slow-wave sleep in the amazonian dolphin, inia electroencephalographic study of sleep in amazonian dolphins, inia geoffrensis, revealed that unihemispheric slow-wave sleep is the dominant sleep type in this species, as in the other two dolphin species that were studied earlier.19873670722
cutaneous gout in an amazon dolphin. 19836643251
hematological, plasmatic and urinary values of three species of cetaceans belonging to the family platanistidae (inia geoffrensis (de blainville, 1817); platanista indi (blyth, 1859); and platanista gangetica (roxburgh, 1801)). 19725056457
composition of wax esters, triglycerides and diacyl glyceryl ethers in the jaw and blubber fats of the amazon river dolphin (inia geoffrensis). 19715548640
blind river dolphin: first side-swimming cetacean.the blind river dolphin (platanista gangetica), first written about by pliny the elder in a.d. 72, was found (10 november 1968) to be the first known side-swimming cetacean. the rudimentary eye lacks the lens, but anatomical evidence suggests that the eye may serve as a light sensor. the underwater sound emissions of this species, although similar to those of the amazon river dolphin (inia geoffrensis), appear to be produced constantly.19695350341
on the brain of the amazon dolphin inia geoffrensis de blainville 1817 (cetacea, susuidae). 19685709043
amazon river dolphins (inia geoffrensis) use a high-frequency short-range biosonar.toothed whales produce echolocation clicks with source parameters related to body size; however, it may be equally important to consider the influence of habitat, as suggested by studies on echolocating bats. a few toothed whale species have fully adapted to river systems, where sonar operation is likely to result in higher clutter and reverberation levels than those experienced by most toothed whales at sea because of the shallow water and dense vegetation. to test the hypothesis that habitat s ...201526447198
vocalizations of amazon river dolphins (inia geoffrensis): characterization, effect of physical environment and differences between populations.the vocal repertoire of the amazon river dolphin and its geographic variations are still poorly known, especially in relation to ecological variables. here the acoustic characteristics of low frequency pulsed vocalizations, with single or multiple pulses, recorded in two protected areas of the amazon were described and differences in acoustic emissions related to water properties were analyzed. both frequency and time parameters differ relative to abiotic condition of water turbidity. changes in ...201627036265
morphology and ultrastructure of the amazon river dolphin (inia geoffrensis) spermatozoa.the spermatozoa from seven adult amazon river dolphins (inia geoffrensis, cetacea: iniidae) were analyzed by light and electron microscopy. the spermatozoa showed an elongated ellipsoid shaped head and a long tail with a well distinguishable midpiece. the head spermatozoa have a smooth surface like other odontocetes examined, with the exception of the delphinidae family. the mean dimensions of the spermatozoa were within the range already reported for other cetaceans. the spermatozoa midpiece, a ...201728257606
amazon river dolphins (inia geoffrensis) modify biosonar output level and directivity during prey interception in the wild.toothed whales have evolved to live in extremely different habitats and yet they all rely strongly on echolocation for finding and catching prey. such biosonar-based foraging involves distinct phases of searching for, approaching and capturing prey, where echolocating animals gradually adjust sonar output to actively shape the flow of sensory information. measuring those outputs in absolute levels requires hydrophone arrays centred on the biosonar beam axis, but this has never been done for wild ...201728526686
[the comparative characteristics of the heart rhythm in cetaceans].in amazon river dolphins, bottle-nosed dolphins and white whales, comparative studies have been made on cardiac electrical activity using electrocardiographic and telemetric techniques. in all the species investigated, certain dependence of cardiac cycle duration on the phase of respiratory pause was observed. a pronounced bradycardia was noted in diving animals which reflects the level of their adaptation to hypoxia and hypoxemia. autocorrelation functions of the dynamic sequences of cardiac in ...20067810261
the separation of whale myoglobins with two-dimensional electrophoresis.five myoglobins (sperm whale, sei whale, hubbs' beaked whale, pilot whale, and amazon river dolphin) were examined using two-dimensional electrophoresis. previous reports indicated that none of these proteins could be separated by using denaturing (in the presence of 8-9 m urea) isoelectric focusing. this result is confirmed in the present study. however, all the proteins could be separated by using denaturing nonequilibrium ph-gradient electrophoresis in the first dimension. additionally, all t ...19883242499
phylogeny of all major groups of cetaceans based on dna sequences from three mitochondrial genes.traditionally, living cetaceans (order cetacea) are classified into two highly distinct suborders: the echolocating toothed whales, odontoceti, and the filter-feeding baleen whales, mysticeti. a molecular phylogeny based on 1,352 base pairs of two mitochondrial ribosomal gene segments and the mitochondrial cytochrome b gene for all major groups of cetaceans contradicts this long-accepted taxonomic subdivision. one group of toothed whales, the sperm whales, is more closely related to the morpholo ...19947755710
molecular identification of evolutionarily significant units in the amazon river dolphin inia sp. (cetacea: iniidae).the amazon river dolphin, genus inia, is endemic to the major river basins of northern south america. no previous studies have focused on the genetic structure of this genus. in this work, 96 dna samples from specimens of this genus were collected in the orinoco basin (four rivers), the putumayo river, a tributary of the colombian amazon and the mamoré, and the tijamuchí and ipurupuru rivers in thebolivian amazon. these samples were used to amplify a fragment of 400 bp of the mitochondrial dna ( ...200812547919
the complete amino acid sequence of the major component myoglobin from the arctic minke whale, balaenoptera acutorostrata.the complete primary structure of the major component myoglobin from the arctic minke whale, balaenoptera acutorostrata, was determined by specific cleavage of the protein to obtain large peptides which are readily degraded by the automatic sequencer. over 80% of the amino acid sequence was established from the three peptides resulting from the cleavage of the apomyoglobin at the two methionine residues with cyanogen bromide along with the four peptides resulting from the cleavage of the methyla ...1977836810
first report of major histocompatibility complex class ii loci from the amazon pink river dolphin (genus inia).we report the first major histocompatibility complex (mhc) dqb1 sequences for the two species of pink river dolphins (inia geoffrensis and inia boliviensis) inhabiting the amazon and orinoco river basins. these sequences were found to be polymorphic within the inia genus and showed shared homology with cetacean dqb-1 sequences, especially, those of the monodontidae and phocoenidae. on the other hand, these sequences were shown to be divergent from those described for other riverine dolphin speci ...200617117356
ascaridoid nematodes of south american mammals, with a definition of a new genus.ascaridoid nematodes occurring in south american mammals are divided into categories based on their possible origin. the affinities are discussed of five species so far known only from the neotropical region. toxocara alienata (rudolphi 1819) is reported from nasua rufa socialis, procyon cancrivorus, and tayassus torquatus. the specimens from t. torquatus are described and found most closely to resemble toxocara mackerrasae from south-east asian and austrialian rodents. anisakis insignis from in ...19826757321
the gonads of the south american dolphins, inia geoffrensis, pontoporia blainvillei, and sotalia fluviatilis. 19715581374
[a microbiological examination of the skin and vaginal mucus of amazon river freshwater dolphins (inia geoffrensis) in relation to an assessment of the physiological state of the animals].there is a definite relation between the state of dolphin's health and the abundance of bacterial associations developing on the skin surface around the dorsal fin. the disease was accompanied by an increase in bacterium amount more than fourfold due to the enhancement of staphylococcus and pseudomonad number. the development of dystrophy in the animal resulted in a threefold decrease in bacterium number. pseudomonas aeruginosa dominated in this case. in the vaginal mucose of female, the develop ...19911809786
the complete amino acid sequence of the major component myoglobin of amazon river dolphin (inia geoffrensis).the complete amino acid sequence of the major component myoglobin from amazon river dolphin, inia geoffrensis, was determined by specific cleavage of the protein to obtain large peptides which are readily degraded by the automatic sequencer. three easily separable peptides were obtained by cleaving the protein with cyanogen bromide at the methionine residues and four peptides were obtained by cleaving the methyl-acetimidated protein with trypsin at the arginine residues. from these peptides over ...19751191640
lipids of freshwater dolphin sotalia fluviatilis: comparison of odontocete bioacoustic lipids and habitat.the melon and jaw lipids of the freshwater dolphin sotalia fluviatilis are composed mainly of isovaleroyl wax esters and diisovaleroyl triglycerides. the blubber fat contains only a trace of wax ester and is mostly tri-(long chain) and monoisovaleroyl triglycerides. detailed gas liquid chromatographic analyses of the intact wax esters and triglycerides and of the derived fatty acids and fatty alcohols indicate common compositional patterns in the wax esters and triglycerides of the respective he ...19751123975
molecular cytogenetic characterization of the amazon river dolphin inia geoffrensis.classical and molecular cytogenetic (18s rdna, telomeric sequence, and line-1 retrotransposon probes) studies were carried out to contribute to an understanding of the organization of repeated dna elements in the amazon river dolphin (boto, inia geoffrensis). twenty-seven specimens were examined, each presenting 2n = 44 chromosomes, the karyotype formula 12m + 14sm + 6st + 10t + xx/xy, and fundamental number (fn) = 74. c-positive heterochromatin was observed in terminal and interstitial position ...201223010983
microsatellite loci for population and parentage analysis in the amazon river dolphin (inia geoffrensis de blainville, 1817).we developed specific primers for microsatellite dna regions for the amazon river dolphin or boto inia geoffrensis, for use in population and conservation genetic studies. we also tested their transferability for two other species, pontoporia blainvillei (sister taxon of i. geoffrensis) and sotalia guianensis. a total of 12 microsatellite loci were polymorphic for the boto. an additional 25 microsatellite loci previously isolated from other cetacean species were also tested in the boto. the 26 p ...200921564703
direction-dependent spectral sensitivity and interaural spectral difference in a dolphin: evoked potential study.sensitivity and interaural intensity difference (iid) dependence on sound frequency and direction was measured in an amazon river dolphin inia geoffrensis by recording the auditory nerve evoked response from the body surface. the maximal sensitivity in the horizontal plane was found when the sound direction was 5 degrees to 10 degrees ipsilateral to the recorded ear; the direction dependence of sensitivity was more pronounced at higher frequencies than at lower ones. the iid reached its peak at ...19938326074
dental caries in the platanistid whale inia geoffrensis. 19665965450
complete primary structure of the major component myoglobin of california gray whale (eschrichtius gibbosus).the complete primary structure of the major component myoglobin from the california gray whale, eschrichtius gibbosus, was determined by specific cleavage of the protein to obtain large peptides for degradation by the automatic sequenator. cleavage at the two methionine residues of the apomyoglobin with cyanogen bromide and at the three arginine residues of the methyl acetimidated protein with trypsin resulted in three and four easily separable peptides, respectively, which when sequenced accoun ...1976938629
complete amino acid sequence of the myoglobin from the atlantic bottlenosed dolphin, tursiops truncatus.the complete amino acid sequence of the major component myoglobin from the atlantic bottlenosed dolphin, tursiops truncatus, was determined by specific cleavage of the protein to obtain large peptides that are readily degraded by the automatic sequencer. three easily separable peptides were obtained by cleaving the protein with cyanogen bromide at the 2 methionine residues and 4 peptides were obtained by cleaving the methyl acetimidated protein with trypsin at the 3 arginine residues. by subject ...1976974068
anti-inflammatory activity of animal oils from the peruvian amazon.animal oils and fats from the fishes electrophorus electricus and potamotrygon motoro, the reptiles boa constrictor, chelonoidis denticulata (geochelone denticulata) and melanosuchus niger and the riverine dolphin inia geoffrensis are used as anti-inflammatory agents in the peruvian amazon. the aim of the study was to assess the topic anti-inflammatory effect of the oils/fats as well as to evaluate its antimicrobial activity and fatty acid composition.201425150527
a retrospective study of pathologic findings in the amazon and orinoco river dolphin (inia geoffrensis) in captivity.river dolphins are especially susceptible to negative human impacts. for their conservation, attempts of relocation or procreation ex situ may become important in the future to avoid their extinction. additional knowledge and medical experiences of river dolphin management in captivity may aid such conservation efforts. the medical records and necropsy and histopathology reports on 123 captive amazon river dolphins (inia geoffrensis) were re-viewed. of these 123 animals, 105 were necropsied and ...200717679501
the freshwater dolphin inia geoffrensis geoffrensis produces high frequency whistles.because whistles are most commonly associated with social delphinids, they have been largely overlooked, ignored, or presumed absent, in solitary freshwater dolphin species. whistle production in the freshwater dolphin, the boto (inia geoffrensis geoffrensis), has been controversial. because of its sympatry with tucuxi dolphins (sotalia fluviatilis), a whistling species, some presume tucuxi whistles might have been erroneously assigned to the boto. using a broadband recording system, we recorded ...200717348541
whistles of boto, inia geoffrensis, and tucuxi, sotalia fluviatilis.whistles were recorded and analyzed from free-ranging single or mixed species groups of boto and tucuxi in the peruvian amazon, with sonograms presented. analysis revealed whistles recorded falling into two discrete groups: a low-frequency group with maximum frequency below 5 khz, and a high-frequency group with maximum frequencies above 8 khz and usually above 10 khz. whistles in the two groups differed significantly in all five measured variables (beginning frequency, end frequency, minimum fr ...200111206170
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