Pathologic findings and causes of death in bottlenose dolphins Tursiops truncatus stranded along the Georgia coast, USA (2007-2013)

2020 ◽  
Vol 141 ◽  
pp. 25-38
Author(s):  
M Seguel ◽  
RC George ◽  
G Maboni ◽  
S Sanchez ◽  
A Page-Karjian ◽  
...  

Between 2007 and 2013, before the 2013 cetacean morbillivirus outbreak, 26 fresh bottlenose dolphin carcasses were necropsied on the coast of Georgia, USA. Here, we present the pathological and microbiological findings associated with their most likely causes of death. The primary cause of death was determined in 25 individuals and included systemic bacterial infection (n = 7), verminous and bacterial bronchopneumonia (n = 5), drowning/entanglement (n = 5), disseminated histoplasmosis (n = 1), intestinal intussusception (n = 1), vegetative endocarditis (n = 1), meningitis (n = 1), necrotizing dermatitis (n = 1), disseminated angiomatosis (n = 1), emaciation (n = 1) and stingray spine trauma (n = 1). Histiocytic and eosinophilic bronchopneumonia associated with Halocerchus sp. infection was observed in 69% of the animals (18/26) and eosinophilic gastritis due to Anisakidae nematodes was found in 36% of the examined stomachs (8/22). Moderate to severe eosinophilic pancreatitis with fibrosis was observed in 4 animals infected with Brachycladiidae trematodes. Proliferative and ulcerative lymphoplasmacytic dermatitis was found in 5 animals and was considered to contribute to deteriorated health status in 2 calves. Pulmonary and lymph node angiomatosis were observed in 15 and 10 animals, respectively. In at least 2 animals, the concentration of polychlorinated biphenyls (PCBs) in the blubber exceeded 1500 µg g-1 of lipid. Bottlenose dolphins stranded on the Georgia coast have a wide range of inflammatory lesions associated with a variety of helminth, bacterial, and fungal pathogens. Some resident animals have also been exposed to high levels of PCB contamination, which could reduce host immunocompetence. Higher exposure to these or other pathogens could result in further decline in the health of resident and migrant dolphin populations in this region.

Weed Science ◽  
1979 ◽  
Vol 27 (5) ◽  
pp. 497-501 ◽  
Author(s):  
C. D. Boyette ◽  
G. E. Templeton ◽  
R. J. Smith

An indigenous, host-specific, pathogenic fungus that parasitizes winged waterprimrose [Jussiaea decurrens(Walt.) DC.] is endemic in the rice growing region of Arkansas. The fungus was isolated and identified asColletotrichum gloeosporioides(Penz.) Sacc. f.sp. jussiaeae(CGJ). It is highly specific for parasitism of winged waterprimrose and not parasitic on creeping waterprimrose (J. repensL. var.glabrescensKtze.), rice (Oryza sativaL.), soybeans [Glycine max(L.) Merr.], cotton (Gossypium hirsutumL.), or 4 other crops and 13 other weeds. The fungus was physiologically distinct from C.gloeosporioides(Penz.) Sacc. f. sp.aeschynomene(CGA), an endemic anthracnose pathogen of northern jointvetch[Aeschynomene virginica(L.) B.S.P.], as indicated by cross inoculations of both weeds. Culture in the laboratory and inoculation of winged waterprimrose in greenhouse, growth chamber and field experiments indicated that the pathogen was stable, specific, and virulent in a wide range of environments. The pathogen yielded large quantities of spores in liquid culture. It is suitable for control of winged waterprimrose. Winged waterprimrose and northern jointvetch were controlled in greenhouse and field tests by application of spore mixtures of CGJ and CGA at concentrations of 1 to 2 million spores/ml of each fungus in 94 L/ha of water; the fungi did not damage rice or nontarget crops.


1994 ◽  
Vol 31 (6) ◽  
pp. 648-653 ◽  
Author(s):  
D. F. Cowan

The thymus glands of 10 bottlenose dolphins, Tursiops truncatus, collected along the Texas Gulf coast were examined using standard histologic and immunocytochemical methods. The thymus gland of Tursiops persists into adult life, represented by medulla and progressively thinning cortex. A network of epithelial cells, including Hassal bodies, is demonstrable using polyclonal anti-cytokeratin antibody. The network condenses, with loss of lymphoid cells as involution progresses. Cysts arise within the condensed network. These cysts, found in eight of 10 animals, increase in number and size with increasing body size. Body size tends to reflect age. Thymic cysts typically have an irregular shape when small but tend to become spherical as they enlarge. Theey may be lined by squamous epithelium of variable thickness. Eventually, the cysts become macroscopic and filled with a colloidlike material and may largely replace the thymus, which may be identified by noncystic remnants adjacent to the cysts.


1998 ◽  
Vol 42 (11) ◽  
pp. 2863-2869 ◽  
Author(s):  
E. Herreros ◽  
C. M. Martinez ◽  
M. J. Almela ◽  
M. S. Marriott ◽  
F. Gomez De Las Heras ◽  
...  

ABSTRACT GM 193663, GM 211676, GM 222712, and GM 237354 are new semisynthetic derivatives of the sordarin class. The in vitro antifungal activities of GM 193663, GM 211676, GM 222712, and GM 237354 against 111 clinical yeast isolates of Candida albicans,Candida kefyr, Candida glabrata, Candida parapsilosis, Candida krusei, and Cryptococcus neoformans were compared. The in vitro activities of some of these compounds against Pneumocystis carinii, 20 isolates each of Aspergillus fumigatus and Aspergillus flavus, and 30 isolates of emerging less-common mold pathogens and dermatophytes were also compared. The MICs of GM 193663, GM 211676, GM 222712, and GM 237354 at which 90% of the isolates were inhibited (MIC90s) were 0.03, 0.03, 0.004, and 0.015 μg/ml, respectively, for C. albicans, including strains with decreased susceptibility to fluconazole; 0.5, 0.5, 0.06, and 0.12 μg/ml, respectively, for C. tropicalis; and 0.004, 0.015, 0.008, and 0.03 μg/ml, respectively, forC. kefyr. GM 222712 and GM 237354 were the most active compounds against C. glabrata, C. parapsilosis, and Cryptococcus neoformans. AgainstC. glabrata and C. parapsilosis, the MIC90s of GM 222712 and GM 237354 were 0.5 and 4 μg/ml and 1 and 16 μg/ml, respectively. The MIC90s of GM 222712 and GM 237354 againstCryptococcus neoformans were 0.5 and 0.25 μg/ml, respectively. GM 193663, GM 211676, GM 222712, and GM 237354 were extremely active against P. carinii. The efficacies of sordarin derivatives against this organism were determined by measuring the inhibition of the uptake and incorporation of radiolabelled methionine into newly synthesized proteins. All compounds tested showed 50% inhibitory concentrations of <0.008 μg/ml. Against A. flavus and A. fumigatus, the MIC90s of GM 222712 and GM 237354 were 1 and 32 μg/ml and 32 and >64 μg/ml, respectively. In addition, GM 237354 was tested against the most important emerging fungal pathogens which affect immunocompromised patients. Cladosporium carrioni, Pseudallescheria boydii, and the yeast-like fungi Blastoschizomyces capitatus and Geotrichum clavatum were the most susceptible of the fungi to GM 237354, with MICs ranging from ≤0.25 to 2 μg/ml. The MICs of GM 237354 against Trichosporon beigelii and the zygomycetesAbsidia corymbifera, Cunninghamella bertholletiae, and Rhizopus arrhizus ranged from ≤0.25 to 8 μg/ml. Against dermatophytes, GM 237354 MICs were ≥2 μg/ml. In summary, we concluded that some sordarin derivatives, such as GM 222712 and GM 237354, showed excellent in vitro activities against a wide range of pathogenic fungi, includingCandida spp., Cryptococcus neoformans, P. carinii, and some filamentous fungi and emerging invasive fungal pathogens.


Author(s):  
Alexandre Gannier

Small boat surveys were organized to study cetaceans of the Marquesas (9°S and 140°W) and the Society Islands (17°S and 150°W) in French Polynesia. Prospecting took place from 12–15 m sailboats, between 1996 and 2001 with systematic visual searching. Boats moved according to sea conditions, at a mean speed of 10 km/h. Effective effort of 4856 km in the Marquesas and 10,127 km in the Societies were logged. Relative abundance indices were processed for odontocetes using data obtained with Beaufort 4 or less. In the Marquesas, 153 on-effort sightings were obtained on 10 delphinids species including the spotted dolphin, spinner dolphin, bottlenose dolphin, melon-headed whale and rough-toothed dolphin. In the Societies, 153 sightings of 12 odontocetes included delphinids (spinner, rough-toothed and bottlenose dolphins, short-finned pilot and melon-headed whales, Fraser's dolphin, Risso's dolphin and pygmy killer whale) and two species of beaked whales, the sperm whale and dwarf sperm whale. Relative abundance indices were higher in the Marquesas than in the Societies both inshore (0.93 ind/km2 against 0.36 ind/km2) and offshore (0.28 ind/km2 against 0.14 ind/km2). Differences in remote-sensed primary production were equally important, the Marquesas waters featuring an annual average of 409 mgC.m−2 · day−1 and the Societies of only 171 mgC · m−2 · day−1. The presence of a narrow shelf around the Marquesas also accounted for differences in odontocete populations, in particular the delphinids.


2004 ◽  
Vol 76 (2) ◽  
pp. 386-392 ◽  
Author(s):  
Carmen Bazúa-Durán

Several methods have been used to compare the whistles produced by dolphins. The two methods used in this study are: (1) a classification of whistle contours in six categories (i.e. constant frequency, upsweep, downsweep, concave, convex, and sine) and (2) the extraction of frequency and time parameters from each whistle contour. Bottlenose Dolphin Tursiops truncatus whistles are described in the same way when comparing whistle contour distributions in each of the six categories and whistle frequency and time parameters using Discriminant Function Analysis. For Spinner Dolphin Stenella longirostris whistles, each method describes whistles differently. Several facts may explain these differences in describing dolphin whistles, such as a greater fluidity of Spinner Dolphin groups when compared to Bottlenose Dolphin groups, greater geographic variation in the whistles of Bottlenose Dolphins than in those of Spinner Dolphins, an average beginning frequency 16% lower than the average ending frequency in Spinner Dolphin whistles compared to a varied relationship for Bottlenose Dolphins, and stricter criteria used to define whistle contour categories in the study of Spinner Dolphin whistles than in the Bottlenose Dolphin whistle study.


2018 ◽  
Vol 99 (4) ◽  
pp. 1017-1023 ◽  
Author(s):  
Flavio Affinito ◽  
Cristobal Olaya Meza ◽  
Aylin Akkaya Bas ◽  
Deborah Brill ◽  
Guy Whittaker ◽  
...  

AbstractPerhaps the world's best-known cetacean, the bottlenose dolphin shows considerable variation in behaviour between and within populations in relation to differences in natural and anthropogenic conditions. Drivers of behavioural variation need to be identified to understand the dynamics of wild dolphin populations. Little research has been published on the bottlenose dolphin population found in the Southern Adriatic Sea. Using a set of spatial, temporal and social predictors, we aimed to investigate what variables are related to the behaviour of an under-studied population of bottlenose dolphins along the coastline of Montenegro. We present the results of a year-long study monitoring the behaviour of bottlenose dolphins along coastal Montenegro. We considered the effect of topography, seasonality and group size. A large proportion of travelling (55%) small groups (mean 4, range 1–9) in shallow waters (<50 m) was observed. We showed that seasonality alone explained behaviour best, with surface-feeding and socializing-resting increasing in autumn and winter. Group size was found to be a result of behavioural choice. We suggest seasonal changes in environmental conditions and anthropogenic pressure may explain the recorded behavioural pattern. This research points to the necessity of increased collaboration in the region to help understand complex patterns in behaviour and habitat use of local dolphin populations if effective conservation measures are to be developed.


2021 ◽  
Author(s):  
Michael Bradshaw ◽  
Holly Packard Bartholomew ◽  
Dylan Hendricks ◽  
Autumn Maust ◽  
Wayne Jurick II

Fungicides are the primary tools to control a wide range of postharvest fungal pathogens. Fungicide resistance is a widespread problem that has reduced fungicide efficacy. Resistance to FRAC 1 chemistries are associated with mutations in amino acid position 198 in the β-tubulin gene. In the current study we conducted a meta-analysis of β-tubulin sequences to infer temporal, spatial, plant host and pathogen genus patterns of fungicide resistance in postharvest fungal pathogens. In total, data was acquired from 2647 specimens from 12 genera of fungal phytopathogens residing in 53 countries, on over 200 hosts collected between 1926-2020. The specimens containing a position 198 mutation were globally distributed in a variety of pathosystems. Analyses showed that there is an association between the mutation and the year an isolate was collected, the pathogen genus, the pathogen host and the collection region. Interestingly, fungicide resistant β-tubulin genotypes have been in a decline since their peak between 2005-2009. FRAC 1 fungicide usage data followed a similar pattern in that applications have been in a decline since their peak between 1997 and 2003. The data shows that, with the reduction of selection pressure, FRAC 1 fungicide resistance in fungal populations will decline within 5-10 years. Based on this line of evidence, we contend that a β-tubulin position 198 mutation has uncharacterized fitness cost(s) on fungi in nature. The compiled dataset can inform end users on the regions and hosts that are most prone to contain resistant pathogens and assist decisions concerning fungicide resistant management strategies.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sehrish Iftikhar ◽  
Aurélie Vigne ◽  
Julia Elisa Sepulveda-Diaz

AbstractFungicides are extensively used in agriculture to control fungal pathogens which are responsible for significant economic impact on plant yield and quality. The conventional antifungal screening techniques, such as water agar and 96-well plates, are based on laborious protocols and bulk analysis, restricting the analysis at the single spore level and are time consuming. In this study, we present a droplet-based microfluidic platform that enables antifungal analysis of single spores of filamentous fungus Alternaria alternata. A droplet-based viability assay was developed, allowing the germination and hyphal growth of single A. alternata spores within droplets. The viability was demonstrated over a period of 24 h and the antifungal screening was achieved using Kunshi/Tezuma as antifungal agent. The efficacy results of the droplet-based antifungal analysis were compared and validated with the results obtained from conventional protocols. The percentage inhibitions assessed by the droplet-based platform were equivalent with those obtained by the other two methods, and the Pearson correlation analysis showed high correlation between the three assays. Taken together, this droplet-based microfluidic platform provides a wide range of potential applications for the analysis of fungicide resistance development as well as combinatorial screening of other antimicrobial agents and even antagonistic fungi.


2012 ◽  
Vol 2012 ◽  
pp. 1-13 ◽  
Author(s):  
Fahd Al Sufiani ◽  
Lee Cyn Ang

Pathologic findings in surgical resections from patients with temporal lobe epilepsy include a wide range of diagnostic possibilities that can be categorized into different groups on the basis of etiology. This paper outlines the various pathologic entities described in temporal lobe epilepsy, including some newly recognized epilepsy-associated tumors, and briefly touch on the recent classification of focal cortical dysplasia. This classification takes into account coexistent pathologic lesions in focal cortical dysplasia.


2020 ◽  
Vol 98 (7) ◽  
pp. 461-479 ◽  
Author(s):  
M. Jedensjö ◽  
C.M. Kemper ◽  
M. Milella ◽  
E.P. Willems ◽  
M. Krützen

Species relationships in the bottlenose dolphin (genus Tursiops Gervais, 1855) are controversial. We carried out a comprehensive osteological study of 264 skulls, including type specimens, and 90 postcranial skeletons of Tursiops spp. to address taxonomic uncertainties in Australia using two-dimensional (2D) measurements, and three-dimensional geometric morphometrics (3DGM), tooth and vertebral counts, and categorical data. Analyses provided support for the presence of two forms, aligned to the Indo-Pacific bottlenose dolphin (Tursiops aduncus (Ehrenberg, 1832)) and the common bottlenose dolphin (Tursiops truncatus (Montagu, 1821)), including type specimens. The Burrunan dolphin (Tursiops australis Charlton-Robb, Gershwin, Thompson, Austin, Owen and McKechnie, 2011) fell well within T. truncatus for both 2D and 3DGM methods. Thirteen Tursiops spp. specimens, no T. australis specimens, were of intermediate size (2D) and could not be assigned to either species. For 3DGM data, there was a strong allometric influence and few non-allometric differences between species. Length and width of the cranium and rostrum were important discriminating variables. Tursiops aduncus was smaller, had more teeth, fewer vertebrae, and more erosion on the pterygoids and frontals than T. truncatus. Overall cranium shape was round in T. aduncus and angular in T. truncatus. Skull length of T. aduncus was smaller in low than in high latitudes. This study highlights the importance of large sample size, multiple analytical methods, and extensive geographical coverage when undertaking taxonomic studies.


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