Internal Anatomy Hydrostatic Equilibrium

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Internal Anatomy Hydrostatic Equilibrium • Tissues are fairly dense • Freshwater 1.0, Sea water 1.025 • Fish components: – Muscle: 1.05 – cartilage: 1.1 – bone/bony scales: 2.0 – Fats: 0.9 • Average fish – 1.06-1.09 meaning they sink • Solutions • Note – more bone = much more weight! Shark Liver Oils Air bladder anatomy • Specific gravity of oils significantly less than water – Specific gravity of 0.86 – Expensive - up to 20% of body mass – Works at any depth Ex: 10 kg fish: 80% @ 1.091 20% @ 0.860 mean: 1.045 -Phsyclistic 1.025/1.045=0.98 -Physostomus Problems with air Bladders Bohr and Root Effects • Pressure problems – Boyles law – P1V1 = P2V2 Bohr effect – Root effect – – Slows speed at which you can change depths • Accessibility to atmosphere • Increase size of fish Other causes of shift: -Increased temperature -Salting out • Secondary losses Rete Mirabile – counter current exchanger Physoclistic Air Bladder Physiology Physostome Air Bladder Physiology Gasses in bladder at high Gasses in bladder at high pressure, exposure to capillary pressure, exposure to capillary Bladder lined with guanine bed will result in absorption bed will result in absorption crystals, impermeable to gas Atmosphere Vein Vein Sphincter controls Artery Sphincter controls gas exposure to oval gas exposure to oval Capillary bed Gas Gland Gas is pumped O2 CO2 release gland. gland. Rete regulated by into bladder metabolic activity in directly from Pneumatic gas gland atmosphere or Gas Gland duct Blood Blood supply through gas gland Passive secretion Regulated by exposure Active secretion to gland Stomach Requires energy Other uses for air bladders Respiration Dorsal View • Light reflection\ • Respiratory Surface Water – Gills – Stomach • Sound production – Lungs – Cutaneous • Body • Sound reception • Buccal cavity • Moving water – Buccal pump – Ram ventilators Gill anatomy Gill anatomy Filament Arch Rakers • Arch • Rakers • Filament • Primary Lamellae • Secondary lamellae Secondary lamellae Primary lamellae Gill Surface area to body weight Cutaneous Respiration • In water: • Problems with too much – aerial uptake (lungs) 40% surface area – skin 30% – gills 30% • In air: • Problems with too little surface area – lungs 63% – skin 37% – gills (opercula closed) 0% 1000 00 Polypteriformes Air breathing fishes Air breathing anatomy • Reduced gill surface area • Most freshwater – primarily swamps – low pH and oxygen • Few marine – Gobiidae – Bleniidae – Cottidae • 374 species, 125 genera, 49 families, 17 orders Obligate vs. facultative air breathers Gill Raker Function • Obligate vs. Facultative air breather • Environmental adaptations to • Raker spacing and size indicate feeding – low oxygen conditions mode – Predator refugia (swamps or deep water) • Large, widely spaced rakers 15 14-15 14 13-14 High BOD in 12-13 13 some habitats 11-12 12 10-11 adds to 9-10 11 • Small, fine rakers problems… 8-9 10 7-8 6-7 9 5-6 4-5 8 Dissolved Oxygen (mg/L) Oxygen Dissolved 7 6 5 4 0 5 10 15 Temperature (C) 20 t) 36000 p 25 p ( y 27000 it 30 n li a 35 18000 S 0 9000 Skulls and Jaws • External representations of major bones..

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BONY FISHES 602 Bony Fishes
click for previous page BONY FISHES 602 Bony Fishes GENERAL REMARKS by K.E. Carpenter, Old Dominion University, Virginia, USA ony fishes constitute the bulk, by far, of both the diversity and total landings of marine organisms encoun- Btered in fisheries of the Western Central Atlantic.They are found in all macrofaunal marine and estuarine habitats and exhibit a lavish array of adaptations to these environments. This extreme diversity of form and taxa presents an exceptional challenge for identification. There are 30 orders and 269 families of bony fishes presented in this guide, representing all families known from the area. Each order and family presents a unique suite of taxonomic problems and relevant characters. The purpose of this preliminary section on technical terms and guide to orders and families is to serve as an introduction and initial identification guide to this taxonomic diversity. It should also serve as a general reference for those features most commonly used in identification of bony fishes throughout the remaining volumes. However, I cannot begin to introduce the many facets of fish biology relevant to understanding the diversity of fishes in a few pages. For this, the reader is directed to one of the several general texts on fish biology such as the ones by Bond (1996), Moyle and Cech (1996), and Helfman et al.(1997) listed below. A general introduction to the fisheries of bony fishes in this region is given in the introduction to these volumes. Taxonomic details relevant to a specific family are explained under each of the appropriate family sections. The classification of bony fishes continues to transform as our knowledge of their evolutionary relationships improves.
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Assessing Turbine Passage Effects on Internal Fish Injury and Delayed
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Sascha Mario Michel Fässler Phd Thesis
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Relationship Between Gill Raker Morphology and Feeding Habits of Hybrid Bigheaded Carps (Hypophthalmichthys Spp.)
Knowledge and Management of Aquatic Ecosystems (2015) 416, 36 Knowledge & c I. Battonyai et al., published by EDP Sciences, 2015 Management of DOI: 10.1051/kmae/2015031 Aquatic Ecosystems www.kmae-journal.org Journal fully supported by Onema Relationship between gill raker morphology and feeding habits of hybrid bigheaded carps (Hypophthalmichthys spp.) I. Battonyai(1),,A.Specziár(1),Z.Vitál(1),A.Mozsár(1), J. Görgényi(2), G. Borics(2),L.G.Tóth(1),G.Boros(1) Received July 6, 2015 Revised October 26, 2015 Accepted October 27, 2015 ABSTRACT Key-words: Bigheaded carps and especially silver carp have been considered as an bigheaded carp, effective biological control for algal blooms, thus were introduced to sev- gill raker eral countries in the last decades, including Hungary. Our aim was to ex- morphology, plore the feeding habits of bigheaded carps in Lake Balaton (Hungary), filter-feeding, where the stock consists mainly of hybrids (silver carp × bighead carp). food size, We examined the relationship between filtering apparatus (gill raker) mor- plankton phology and size-distribution of planktonic organisms in the food. We failed to find any significant relationship between gill raker parameters and plankton composition in the filtered material. Bigheaded carps with vari- ous types of gill rakers consumed food within the same size-spectrum, independently of the rate of hybridization. However, the linkage between the proportion of different planktonic size classes in the water and in the diet of fish was detectable in case of both phytoplankton and zooplankton consumption, suggesting that the seasonally variable availability of differ- ent food items was an important factor in determining the food composi- tion of bigheaded carps.
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Pictorial Guide to the Gill Arches of Gadids and Pleuronectids in The
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Fine Structure of the Gas Bladder of Alligator Gar, Atractosteus Spatula Ahmad Omar-Ali1, Wes Baumgartner2, Peter J
www.symbiosisonline.org Symbiosis www.symbiosisonlinepublishing.com International Journal of Scientific Research in Environmental Science and Toxicology Research Article Open Access Fine Structure of the Gas Bladder of Alligator Gar, Atractosteus spatula Ahmad Omar-Ali1, Wes Baumgartner2, Peter J. Allen3, Lora Petrie-Hanson1* 1Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762, USA 2Department of Pathobiology and Population Medicine, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762, USA 3Department of Wildlife, Fisheries and Aquaculture, College of Forest Resources, Mississippi State University, Mississippi State, MS 39762, USA Received: 1 November, 2016; Accepted: 2 December, 2016 ; Published: 12 December, 2016 *Corresponding author: Lora Petrie-Hanson, Associate Professor, College of Veterinary Medicine, 240 Wise Center Drive PO Box 6100, Mississippi State, MS 39762, USA, Tel: +1-(601)-325-1291; Fax: +1-(662)325-1031; E-mail: [email protected] Lepisosteidae includes the genera Atractosteus and Lepisosteus. Abstract Atractosteus includes A. spatula (alligator gar), A. tristoechus Anthropogenic factors seriously affect water quality and (Cuban gar), and A. tropicus (tropical gar), while Lepisosteus includes L. oculatus (spotted gar), L. osseus (long nose gar), L. in the Mississippi River and the coastal estuaries. Alligator gar platostomus (short nose gar), and L. platyrhincus (Florida gar) (adversely affect fish )populations. inhabits these Agricultural waters andrun-off is impactedaccumulates by Atractosteus spatula [2,6,7]. Atractosteus are distinguishable from Lepisosteus by agricultural pollution, petrochemical contaminants and oil spills. shorter, more numerous gill rakers and a more prominent accessory organ. The gas bladder, or Air Breathing Organ (ABO) of second row of teeth in the upper jaw [2].
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Gill Rakers of Basking Sharks (Lamniformes: Cetorhinidae) from the Tertiary of Sakhalin Island, Russia
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RESEARCH ARTICLE Bottles As Models: Predicting the Effects of Varying Swimming Speed and Morphology on Size Selectivity and Filtering Efficiency in Fishes
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A Preliminary Assessment of Barotrauma Injuries and Acclimation Studies for Three Fish Species Final Report
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Comparison of Gill Raker Morphology of Alewife from Recent and Bygone Introductions
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Gill Rakers and Teeth of Three Pleuronectiform Species (Teleostei) of the Baltic Sea: a Microichthyological Approach
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