keyword
MENU ▼
Read by QxMD icon Read
search

Elasmobranch

keyword
https://www.readbyqxmd.com/read/28207874/growth-and-life-history-variability-of-the-grey-reef-shark-carcharhinus-amblyrhynchos-across-its-range
#1
Darcy Bradley, Eric Conklin, Yannis P Papastamatiou, Douglas J McCauley, Kydd Pollock, Bruce E Kendall, Steven D Gaines, Jennifer E Caselle
For broadly distributed, often overexploited species such as elasmobranchs (sharks and rays), conservation management would benefit from understanding how life history traits change in response to local environmental and ecological factors. However, fishing obfuscates this objective by causing complex and often mixed effects on the life histories of target species. Disentangling the many drivers of life history variability requires knowledge of elasmobranch populations in the absence of fishing, which is rarely available...
2017: PloS One
https://www.readbyqxmd.com/read/28207832/towards-sustainable-fishery-management-for-skates-in-south-america-the-genetic-population-structure-of-zearaja-chilensis-and-dipturus-trachyderma-chondrichthyes-rajiformes-in-the-south-east-pacific-ocean
#2
Carolina Vargas-Caro, Carlos Bustamante, Michael B Bennett, Jennifer R Ovenden
The longnose skates (Zearaja chilensis and Dipturus trachyderma) are the main component of the elasmobranch fisheries in the south-east Pacific Ocean. Both species are considered to be a single stock by the fishery management in Chile however, little is known about the level of demographic connectivity within the fishery. In this study, we used a genetic variation (560 bp of the control region of the mitochondrial genome and ten microsatellite loci) to explore population connectivity at five locations along the Chilean coast...
2017: PloS One
https://www.readbyqxmd.com/read/28179057/mid-atlantic-elasmobranchs-suitable-metal-scouts
#3
Paulo Torres, Regina Tristão da Cunha, Armindo Dos Santos Rodrigues
Heavy metals are a hazard to marine fauna and human health. In this study we assess stable isotopes and metal content in Prionace glauca and Isurus oxyrinchus and analyse these results within and among other species and across regions and geographical areas. Also, we evaluate their suitability, together with Raja clavata and Galeorhinus galeus, as Mid-Atlantic bioindicators. Prionace glauca and I. oxyrinchus shared the same trophic level in a pelagic food web and did not present significant differences between genders or metals, except for As...
February 5, 2017: Marine Pollution Bulletin
https://www.readbyqxmd.com/read/28177292/intestinal-helminth-fauna-of-the-shortfin-mako-isurus-oxyrinchus-elasmobranchii-lamnidae-in-the-northeast-atlantic-ocean
#4
Jaime Penadés-Suay, Jesús Tomás, Manuel Merchán, Francisco Javier Aznar
Large oceanic sharks represent a suitable model to investigate the influence of a host's oceanic conditions on the structure of its helminth communities. In this study, we describe the intestinal helminth fauna, and investigate determinants of infracommunity structure, in 39 specimens of shortfin mako Isurus oxyrinchus collected in the NE Atlantic. Six cestode species were found in the spiral valve of makos: 3 are typical from lamnid sharks, namely, gravid specimens of Clistobothrium montaukensis, Gymnorhynchus isuri and Ceratobothrium xanthocephalum, and 3 are immature specimens of cestode species common to several elasmobranchs, namely, Dinobothrium septaria, Nybelinia lingualis, and Phyllobothrium cf...
February 8, 2017: Diseases of Aquatic Organisms
https://www.readbyqxmd.com/read/28168114/are-sawfishes-still-present-in-mozambique-a-baseline-ecological-study
#5
Ruth H Leeney
Sawfishes (Pristidae) were formerly abundant in the western Indian Ocean, but current data on sawfish presence and distribution are lacking for most of the region. This paper summarises historical records of sawfishes in Mozambican waters and presents the findings of the first assessment of the presence and status of sawfishes in Mozambique. A countrywide baseline assessment was undertaken between May and July 2014, using interviews with artisanal, semi-industrial and industrial fishers, fish traders and fisheries monitoring staff as the primary source of information on sawfish distribution, recent catches, socio-economic value and cultural importance...
2017: PeerJ
https://www.readbyqxmd.com/read/28165147/a-review-on-the-morphology-of-ovarian-follicles-in-elasmobranchs-a-case-study-in-rhizoprionodon-taylori
#6
REVIEW
Daniela S Waltrick, Colin A Simpfendorfer, Cynthia A Awruch
The identification of the elasmobranch secondary ovarian follicles and their function can be challenging and the inconsistent use of terminology derived from other taxa is a matter of ongoing debate. In this study, the available information on the histology of the elasmobranch secondary ovarian follicles derived from atresia (preovulatory follicles) or ovulation (postovulatory follicles) is reviewed highlighting their morphology and steroidogenic capacity. Based on this literature review, the ovarian follicles of the Australian sharpnose shark Rhizoprionodon taylori were classified according to their preovulatory or postovulatory origin...
February 6, 2017: Journal of Morphology
https://www.readbyqxmd.com/read/28153417/association-between-chronic-organochlorine-exposure-and-immunotoxicity-in-the-round-stingray-urobatis-halleri
#7
Jillian M Sawyna, Weston R Spivia, Kelly Radecki, Deborah A Fraser, Christopher G Lowe
Chronic organochlorine (OC) exposure has been shown to cause immune impairment in numerous vertebrate species. To determine if elasmobranchs exhibited compromised immunity due to high OC contamination along the coastal mainland of southern California, innate immune function was compared in round stingrays (Urobatis halleri) collected from the mainland and Santa Catalina Island. Proliferation and phagocytosis of peripheral blood, splenic, and epigonal leukocytes were assessed. Percent phagocytosis and mean fluorescence intensity (MFI) were evaluated by quantifying % leukocytes positive for, and relative amounts of ingested fluorescent E...
January 30, 2017: Environmental Pollution
https://www.readbyqxmd.com/read/28144984/embryonic-development-of-the-axial-column-in-the-little-skate-leucoraja-erinacea
#8
Katharine E Criswell, Michael I Coates, J Andrew Gillis
The morphological patterns and molecular mechanisms of vertebral column development are well understood in bony fishes (osteichthyans). However, vertebral column morphology in elasmobranch chondrichthyans (e.g., sharks and skates) differs from that of osteichthyans, and its development has not been extensively studied. Here, we characterize vertebral development in an elasmobranch fish, the little skate, Leucoraja erinacea, using microCT, paraffin histology, and whole-mount skeletal preparations. Vertebral development begins with the condensation of mesenchyme, first around the notochord, and subsequently around the neural tube and caudal artery and vein...
January 31, 2017: Journal of Morphology
https://www.readbyqxmd.com/read/28132643/comparative-transcriptomics-of-elasmobranchs-and-teleosts-highlight-important-processes-in-adaptive-immunity-and-regional-endothermy
#9
Nicholas J Marra, Vincent P Richards, Angela Early, Steve M Bogdanowicz, Paulina D Pavinski Bitar, Michael J Stanhope, Mahmood S Shivji
BACKGROUND: Comparative genomic and/or transcriptomic analyses involving elasmobranchs remain limited, with genome level comparisons of the elasmobranch immune system to that of higher vertebrates, non-existent. This paper reports a comparative RNA-seq analysis of heart tissue from seven species, including four elasmobranchs and three teleosts, focusing on immunity, but concomitantly seeking to identify genetic similarities shared by the two lamnid sharks and the single billfish in our study, which could be linked to convergent evolution of regional endothermy...
January 30, 2017: BMC Genomics
https://www.readbyqxmd.com/read/28112880/clasper-gland-morphology-and-development-in-potamotrygon-magdalenae-elasmobranchii-potamotrygonidae
#10
Paola Anaya-López, Martha Patricia Ramírez-Pinilla
Clasper gland morphology and development in Potamotrygon magdalenae and its relation with the acquisition of reproductive maturity is described in males of different developmental stages (embryos, neonates, juveniles, and reproductively active and resting adults). The glands are subcutaneous masses in the proximal base of each clasper. They are partially bilobate organs with a ventral groove that bears a row of papillae. Glands tend to be asymmetric, the left gland has a larger size, a trend that has been observed in other organs of elasmobranchs...
January 23, 2017: Journal of Morphology
https://www.readbyqxmd.com/read/28104230/first-evidence-of-persistent-organic-contaminants-as-potential-anthropogenic-stressors-in-the-barndoor-skate-dipturus-laevis
#11
Kady Lyons, Douglas H Adams
Although exploited populations of elasmobranchs may be able to recover from fishing pressure, there is little information regarding the Barndoor Skate's ability to cope with other anthropogenic stressors such as organic contaminants (OCs). Legacy OCs were measured in liver, muscle and ova from fourteen Barndoor Skates with mature skates having significantly greater mean concentrations of OCs than immature skates, demonstrating bioaccumulation with age. Using Toxic Equivalency Factors, skates were found to have levels of PCBs that have been shown to elicit negative physiological responses in other fishes and these results highlight the need for future studies to investigate the potential impacts that bioaccumulated organic contaminants have on the recovery and conservation of this vulnerable species...
January 16, 2017: Marine Pollution Bulletin
https://www.readbyqxmd.com/read/28093310/effects-of-glucose-and-insulin-administration-on-glucose-transporter-expression-in-the-north-pacific-spiny-dogfish-squalus-suckleyi
#12
Courtney A Deck, W Gary Anderson, Patrick J Walsh
Elasmobranchs (sharks, skates, and rays) are a primarily carnivorous group of fish, consuming few carbohydrates. Further, they tend to exhibit delayed responses to glucose and insulin administration in vivo relative to mammals, leading to a presumption of glucose-intolerance. To investigate the glucoregulatory capabilities of the spiny dogfish (Squalus suckleyi), plasma glucose concentration, muscle and liver glycogen content, and glucose transporter (glut1 and 4) mRNA levels were measured following intra-arterial administration of bovine insulin (10 ng kg(-1)) or an approximate doubling of fasting plasma glucose concentration...
January 13, 2017: General and Comparative Endocrinology
https://www.readbyqxmd.com/read/28091617/switch-from-sexual-to-parthenogenetic-reproduction-in-a-zebra-shark
#13
Christine L Dudgeon, Laura Coulton, Ren Bone, Jennifer R Ovenden, Severine Thomas
Parthenogenesis is a natural form of asexual reproduction in which embryos develop in the absence of fertilisation. Most commonly found in plants and invertebrate organisms, an increasing number of vertebrate species have recently been reported employing this reproductive strategy. Here we use DNA genotyping to report the first demonstration of an intra-individual switch from sexual to parthenogenetic reproduction in a shark species, the zebra shark Stegostoma fasciatum. A co-housed, sexually produced daughter zebra shark also commenced parthenogenetic reproduction at the onset of maturity without any prior mating...
January 16, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28080920/phaeohyphomycosis-associated-with-ossification-of-the-skull-and-cervical-vertebrae-in-a-swell-shark-cephaloscyllium-ventriosum
#14
Claire D Erlacher-Reid, Hendrik H Nollens, Todd L Schmitt, Judy St Leger, Sarena Sunico
A female, captive bred, juvenile swell shark ( Cephaloscyllium ventriosum ) was observed swimming in tight circles and rolling. Radiographs and computed tomography of this individual revealed extensive cartilage mineralization of the skull and cranial cervical vertebrae compared with diagnostic images of clinically healthy conspecifics. Gross necropsy and histopathologic examination revealed ossification and fibrosis of the cartilaginous matrix of the skull and cervical vertebrae with deep invasion by a pigmented hyphal fungus...
December 2016: Journal of Zoo and Wildlife Medicine: Official Publication of the American Association of Zoo Veterinarians
https://www.readbyqxmd.com/read/28080905/plasma-protein-electrophoresis-and-select-acute-phase-proteins-in-healthy-bonnethead-sharks-sphyrna-tiburo-under-managed-care
#15
Michael W Hyatt, Cara L Field, Tonya M Clauss, Kristopher L Arheart, Carolyn Cray
Preventative health care of elasmobranchs is an important but understudied field of aquatic veterinary medicine. Evaluation of inflammation through the acute phase response is a valuable tool in health assessments. To better assess the health of bonnethead sharks ( Sphyrna tiburo ) under managed care, normal reference intervals of protein electrophoresis (EPH) and the acute phase proteins, C-reactive protein (CRP) and haptoglobin (HP), were established. Blood was collected from wild caught, captive raised bonnethead sharks housed at public aquaria...
December 2016: Journal of Zoo and Wildlife Medicine: Official Publication of the American Association of Zoo Veterinarians
https://www.readbyqxmd.com/read/28062996/trebius-benzi-n-sp-siphonostomatoida-trebiidae-infecting-squalus-acutipinnis-regan-off-south-africa
#16
Susan M Dippenaar
Trebius Krøyer, 1838 currently consists of 15 accepted species all infecting elasmobranchs. Apart from two species, i.e. T. caudatus Krøyer, 1838 and T. latifurcatus Wilson, 1921, that have been reported from ten and eight host species, respectively, the other 13 species have each been reported from only one or two host species. Trebius benzi n. sp., collected from Squalus acutipinnis Regan, is described and illustrated after examination through stereo- and compound microscopes. This species can be distinguished from the other known species by a combination of characters including an abdomen that is shorter than the genital complex, a maxillule with an endite that consists of a single-tined dentiform process, sternal furca tines that are blunt and as long as the base, and the innermost spine of the last exopodal segment of leg 1 the shortest...
January 2017: Systematic Parasitology
https://www.readbyqxmd.com/read/28026018/a-preliminary-investigation-into-the-morphology-of-oral-papillae-and-denticles-of-blue-sharks-prionace-glauca-with-inferences-about-its-functional-significance-across-life-stages
#17
Bianca de S Rangel, Natascha Wosnick, Neil Hammerschlag, Adriano P Ciena, José Roberto Kfoury Junior, Rose E G Rici
Sensory organs in elasmobranchs (sharks, skates, rays) detect and respond to a different set of biotic and/or abiotic stimuli, through sight, smell, taste, hearing, mechanoreception and electroreception. Although gustation is crucial for survival and essential for growth, mobility, and maintenance of neural activity and the proper functioning of the immune system, comparatively little is known about this sensory system in elasmobranchs. Here we present a preliminary investigation into the structural and dimensional characteristics of the oral papillae and denticles found in the oropharyngeal cavity of the blue shark (Prionace glauca) during embryonic development through adulthood...
December 27, 2016: Journal of Anatomy
https://www.readbyqxmd.com/read/28018617/cutting-blade-dentitions-in-squaliform-sharks-form-by-modification-of-inherited-alternate-tooth-ordering-patterns
#18
Charlie Underwood, Zerina Johanson, Moya Meredith Smith
The squaliform sharks represent one of the most speciose shark clades. Many adult squaliforms have blade-like teeth, either on both jaws or restricted to the lower jaw, forming a continuous, serrated blade along the jaw margin. These teeth are replaced as a single unit and successor teeth lack the alternate arrangement present in other elasmobranchs. Micro-CT scans of embryos of squaliforms and a related outgroup (Pristiophoridae) revealed that the squaliform dentition pattern represents a highly modified version of tooth replacement seen in other clades...
November 2016: Royal Society Open Science
https://www.readbyqxmd.com/read/27977062/comparison-of-hematology-plasma-biochemistry-and-blood-gas-variables-between-2-venipuncture-sites-in-southern-stingrays-dasyatis-americana
#19
Brianne E Phillips, Emily F Christiansen, Michael K Stoskopf, Heather Broadhurst, Robert George, Craig A Harms
BACKGROUND: The Southern Stingray (Dasyatis americana) is a batoid elasmobranch frequently exhibited in zoological institutions. Blood is commonly collected from the caudal hemal arch at the tail base in stingrays for the purpose of health assessment and clinical pathology tests. An alternative site that allows a dorsal or ventral approach without necessitating puncture of a cartilaginous structure has been identified between the cartilaginous pectoral fin rays (ceratotrichia). OBJECTIVES: The purpose of the study was to compare CBC, plasma biochemistry analytes, and blood gas variables between blood samples collected from the caudal and pectoral fin vasculature sites of the Southern Stingray...
December 2016: Veterinary Clinical Pathology
https://www.readbyqxmd.com/read/27973339/a-new-genus-of-rhinebothriidean-cestodes-from-batoid-elasmobranchs-with-the-description-of-five-new-species-and-two-new-combinations
#20
Florian B Reyda, Claire J Healy, Andrew R Haslach, Timothy R Ruhnke, Tara L Aprill, Michael P Bergman, Andrew L Daigler, Elsie A Dedrick, Illari Delgado, Kathryn S Forti, Kaylee S Herzog, Rebecca S Russell, Danielle D Willsey
Survey work of batoid elasmobranchs in the eastern Atlantic and Indo-Pacific revealed multiple species of a new genus of cestode. Stillabothrium Healy et Reyda gen. n. (Rhinebothriidea: Escherbothriidae) is unique in its possession of an even number of non-medial longitudinal septa in the posterior portion of the bothridia, resulting in a series of loculi that are longer than wide (i.e. vertically oriented) and are arranged in columns. Five new species of Stillabothrium are described, S. ashleyae Willsey et Reyda sp...
November 10, 2016: Folia Parasitologica
keyword
keyword
66107
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"