On the Respiration of the Killifish Oryzias Latipes

1973 ◽  
Vol 58 (2) ◽  
pp. 305-325
Author(s):  
SHUN-ICHI UMEZAWA ◽  
HIDEKI WATANABE
Keyword(s):  
Oxygen Consumption ◽  
Marked Change ◽  
The Body ◽  
Platinum Electrodes ◽  
Head Region ◽  
Active Electrode ◽  
Small Surface ◽  
Flow Rates ◽  
Ventilatory Frequency ◽  
Gill Opening

1. Factors influencing respiration in this small surface-living freshwater fish (100-290 mg body weight) have been investigated using through-flow respirometers. 2. When the rate of flow over the resting fish is increased, there is an increase in oxygen consumption, but no marked change in ventilatory frequency. Percentage of oxygen removed from the water during its passage over the fish decreases with increase in flow rate in some ranges, and seems to increase again with even greater flow rates notwithstanding a rise in oxygen consumption. 3. The standard oxygen consumption is in the range 250-400 c.c./kg/h at 20°C, and 300-500 c.c./kg/h at 25°C with average flow rates (50-150 c.c./h). 4. Oxygen consumption of the fish is directly related to ambient POO2 over the range 40-500 mmHg. Increases both in ventilatory frequency and in percentage of oxygen removed from the water during its passage over the fish occur during hypoxia, but decrease with increases in ambient POO2 although O2 uptake increases. 5. Ventilatory frequency decreases during darkness and increases in light. After stimulation with light both oxygen consumption and percentage of oxygen removed showed temporary high rates which only gradually subsided. 6. Ventilation volume, measured directly by collecting the water which had passed over the gills, is about 800 c.c./min/kg at 25°C, when the positive hydrostatic pressure is about 5 mm of water. 7. Determinations of gill areas of the fish gave values in the range of 1211-1700 mm2/g weight. The larger values in the fish are probably related to its greater oxygen consumption. 8. Slow potentials associated with respiratory movements were recorded around the head region of the fish by means of external platinum electrodes. When the active electrode was shifted tailwards along the body, the size of the potentials changed, being maximal just posterior to the opercular opening and rather large beside the mouth. The higher values obtained in the potential were 900-1100 µV. The polarity of the potential was reversed at a position anterior to the gill opening.

Oxygen Consumption and Gill Water Flow in the Dogfish Scyliorhinus Canicula L

1968 ◽  
Vol 49 (3) ◽  
pp. 557-564 ◽  
Author(s):  
G. M. HUGHES ◽  
SHUN-ICHI UMEZAWA
Keyword(s):  
Oxygen Consumption ◽  
Hydrostatic Pressure ◽  
Pressure Gradient ◽  
Linear Relationship ◽  
Water Flow ◽  
Marked Change ◽  
Respiratory Frequency ◽  
Flow Rates ◽  
Scyliorhinus Canicula ◽  
The Relationship

1. Determinations of the standard oxygen consumption of the dogfish Scyliorhinus canicula, by several different methods, gave values in the range of 20-55 c.c./kg./hr. at 12°C. 2. When the rate of water flow over the resting fish is increased, there is an increase in oxygen consumption, but no marked change in respiratory frequency at the flow rates studied. An increase of respiratory frequency took place when the PO2 of the inspired water was reduced. 3. The ventilation volume of the dogfish was measured by collecting the water in chambers after it had passed over the gills. The resting ventilation volume was about 120 c.c./min./kg. at 12° C. 4. The relationship between the flow across the gills and the imposed hydrostatic pressure gradient (Δp) showed a linear relationship. The fish was unable to continue pumping water across the gills against adverse gradients in excess of 0.7 cm. H2O. 5. When the flow across the gills was relatively low, utilization of oxygen of at least 70% was observed, but with increasing flow rates this fell to between 40 and 50%.

A small electrolytically driven infusion pump

1965 ◽  
Vol 20 (4) ◽  
pp. 793-795
Author(s):  
A. Baumgarten ◽  
C. C. Curtain
Keyword(s):  
Flow Rate ◽  
Electrolyte Solution ◽  
Human Subjects ◽  
Infusion Pump ◽  
Power Source ◽  
The Body ◽  
Platinum Electrodes ◽  
Intravenous Catheter ◽  
Flow Rates ◽  
Polyurethane Sponge

An electrolytically driven infusion pump has been constructed in which the pressure of gas generated by electrolysis is used to propel the infusate at controllable flow rates. The unit has over-all dimensions of 12.5 x 4.0 cm and consists of a chamber containing the electrolyte solution in a polyurethane sponge inserted between platinum electrodes and a chamber containing a mercury battery which serves as the power source. The infusate is contained in 4.5-mm diameter polythene tubing wound about the body of the pump. A small polythene valve inserted between the tubing and an intravenous catheter prevents reflux of blood. The pump has a capacity of up to 25 ml and a flow rate of 0.5—25 ml/hr. It can operate in any position and is designed for use in human subjects and unrestrained animals. portable infusion pump; self-contained infusion pump; nonmechanical pump Submitted on November 9, 1964

Two-dimensional scattering of a plane compressional wave by surface imperfections

1969 ◽  
Vol 59 (3) ◽  
pp. 1349-1364
Author(s):  
Ivor K. McIvor
Keyword(s):  
Order Approximation ◽  
Strong Dependence ◽  
Plane Waves ◽  
Compressional Wave ◽  
Elastic Half Space ◽  
Kernel Functions ◽  
The Body ◽  
Angle Of Incidence ◽  
Small Surface ◽  
Surface Imperfections

abstract A perturbation method for treating the scattering of plane waves by small surface imperfections on an elastic half space is presented. The solution to the first order approximation is given as convolution integrals of the surface imperfection with kernel functions defined by Fourier inversion integrals. The evaluation of these integrals is discussed and their asymptotic representations determined. The far field scattered displacements are explicitly obtained for arbitrary imperfections. The scattered field consists of a Rayleigh surface wave and four body phases which at the free surface travel with the speed of dilational or distortional waves. Numerical examples are given. In particular the error in the apparent angle of emergence due to the scattered waves is obtained. The body phases exhibit the familiar 3/2 geometric attenuation, but still may make a significant contribution at moderately long distances. A strong dependence of the magnitude of the error on the angle of incidence is demonstrated.

The Oxygen Consumption of an Echiuroid, Bonellia Viridis Rolando

1968 ◽  
Vol 48 (2) ◽  
pp. 427-434
Author(s):  
A. E. BRAFIELD
Keyword(s):  
Oxygen Consumption ◽  
Body Size ◽  
Continuous Flow ◽  
Muscular Activity ◽  
Dry Weight ◽  
The Body ◽  
Body Region ◽  
Rate Of Oxygen Consumption

1. The oxygen consumption of the echiuroid Bonellia viridis has been investigated by means of a continuous-flow polarographic respirometer. 2. The general rate of oxygen consumption per unit dry weight is similar to that characteristic of polychaetes, and declines exponentially with increasing body size. 3. The rate of oxygen consumption rises in the light and falls again if darkness is restored. 4. The oxygen consumption of the isolated proboscis plus that of the isolated body region corresponds closely to that of the entire animal. 5. The oxygen consumption per unit dry weight of the proboscis is considerably higher than that of the body region. 6. The oxygen consumption of an isolated body region increases in the presence of light, but that of an isolated proboscis does not. 7. These findings are discussed in relation to the biology of the animal, observed muscular activity, and the occurrence of the pigment bonellin.

Oxygen consumption and blood flow in the hypothermic, perfused kidney

1959 ◽  
Vol 197 (5) ◽  
pp. 1111-1114 ◽  
Author(s):  
Matthew N. Levy
Keyword(s):  
Blood Pressure ◽  
Blood Flow ◽  
Oxygen Consumption ◽  
Blood Viscosity ◽  
The Body ◽  
Peripheral Artery ◽  
Isolated Kidney ◽  
Arterial Blood ◽  
Oxygen Difference ◽  
Appreciable Reduction

Temperature was diminished in a stepwise fashion in the isolated kidney of the dog perfused from a peripheral artery of the original, normothermic animal. Decreased temperature resulted in an appreciable reduction of renal blood flow at constant arterial blood pressure. Increased blood viscosity and vasoconstriction were both responsible for this reduction of flow. Hypothermia also resulted in a reduction in arteriovenous oxygen difference which was roughly proportional to the centigrade temperature. Furthermore, hypothermia exerted a marked but reversible depression of the rate of oxidative metabolism. This effect was relatively more severe than the changes for the body as a whole at equivalent temperatures reported by other investigators.

scholarly journals The Function of the Gills of Mayfly Nymphs from Different Habitats

1939 ◽  
Vol 16 (3) ◽  
pp. 363-373 ◽  
Author(s):  
C. A. WINGFIELD
Keyword(s):  
Oxygen Consumption ◽  
Oxygen Content ◽  
The Body ◽  
Gaseous Exchange ◽  
Low Oxygen ◽  
Respiratory Mechanism ◽  
Tracheal Gills ◽  
Cloeon Dipterum ◽  
Gill Function ◽  
Oxygen Concentrations

1. The oxygen consumption of normal and gill-less nymphs of the mayflies Baetis sp., Cloeon dipterum and Ephemera vulgata has been measured at various oxygen concentrations. 2. It has been found that over the complete range of oxygen concentrations studied, the tracheal gills do not aid oxygen consumption in Baetis sp. In Cloeon dipterum, at all oxygen concentrations tested, no gaseous exchange takes place through the gills; at low oxygen concentrations, however, the gills function as an accessory respiratory mechanism in ventilating the respiratory surface of the body and so aid oxygen consumption. In Ephemera Vulgata the gills aid oxygen consumption even at high oxygen concentrations. In this species the gills may function both as true respiratory organs and as a ventilating mechanism. 3. It is shown that the differences in gill function can be related to the oxygen content of the habitat of each species.

scholarly journals Opposite asymmetries of face and trunk and of kissing and hugging, as predicted by the axial twist hypothesis

2019 ◽  
Author(s):  
Marc HE de Lussanet
Keyword(s):  
Bilateral Symmetry ◽  
Optic Chiasm ◽  
Early Embryo ◽  
The Body ◽  
Head Region ◽  
Evolutionary Selection ◽  
Left Handed ◽  
Secondary Feature ◽  
Half Turn ◽  
Axial Twist

The contralateral organization of the forebrain and the crossing of the optic nerves in the optic chiasm represent a long-standing conundrum. According to the Axial Twist Hypothesis (ATH) the rostral head and the rest of the body are twisted with respect to each other to form a left-handed half turn. This twist is the result, mainly, of asymmetric, twisted growth in the early embryo. Evolutionary selection tends to restore bilateral symmetry. Since selective pressure will decrease as the organism approaches symmetry, we expected a small control error in the form of a small, residual right-handed twist. We found that the mouth-eyes-nose (rostral head) region shows a left-offset with respect to the ears (posterior head) by up to 0.8° (P<0.01, Bonferroni-corrected). Moreover, this systematic aurofacial asymmetry was larger in young children (on average up to 3°) and reduced with age. Finally, we predicted and found a right-sided bias for hugging (78%) and a left-sided bias for kissing (69%). Thus, all predictions were confirmed by the data. These results are all in support of the ATH, whereas the pattern of results is not explained by existing alternative theories. As of the present results, the ATH is the first theory for the contralateral forebrain and the optic chiasm whose predictions have been tested empirically. We conclude that humans (and all other vertebrates) are fundamentally asymmetric, both in their anatomy and their behavior. This supports the thesis that the approximate bilateral symmetry of vertebrates is a secondary feature, despite their being bilaterians.

scholarly journals Intra-specific morphological and morphometric variability of Radopholus similis (Cobb, 1893) Thorne, 1949

2018 ◽  
Vol 10 (3) ◽  
pp. 841-846 ◽  
Author(s):  
S. Roy ◽  
K Roy ◽  
S. Sarkar ◽  
A Rathod ◽  
J. Hore
Keyword(s):  
The Body ◽  
Radopholus Similis ◽  
Body Width ◽  
Head Region ◽  
Morphometric Characters ◽  
Lateral Field ◽  
Oesophageal Gland ◽  
Morphometric Features ◽  
Basal Bulb ◽  
Stylet Length

All the root inhabiting migratory endoparasitic nematode populations of Radopholus procured from banana crop of Vellayani, Thiruvananthapuram, Kerala were identified as Radopholus similis. Heat killed females were straight to slightly ventrally curved posteriorly. Female’s head was low, rounded, continuous or slightly setoff with the body contour. Females were 500-660 µm long and were comparatively longer than males. Males had button shaped head set off by a constriction; female with three to five lip annuli, four crenate and areolated lateral incisures, stylet 14-18 µm long with rounded knobs, vulva post-equatorial (58%), sometimes with slight protuberant lips, ovary paired and equally developed, oesophageal gland overlapped the intestine dorsally, tail elongate-conoid with narrowly rounded terminus. The stylet length (µm), width of stylet knob (µm), distance of excretory pore from anterior end (µm), distance from head to basal bulb (µm), lateral field structure, shape of stylet knob, head region, position of phasmid, tail shape with its terminus, morphometric values like m%, o% and v% and a, c and c´ ratios of females were stable (CV<12%) features. There is an existence of intra-specific variability in the morphological and morphometric features of R. similis. The main morphological diversity was observed with P% of male and female, b ratio of female and stylet length, distance of DEGO from stylet base, o% and T% of male. All the root inhabiting migratory endoparasitic nematode populations of Radopholus Thorne, 1949 procured from banana of Vellayani, Thiruvananthapuram, Kerala were identified as Radopholus similis (Cobb, 1893) Thorne, 1949. A high degree of intra-specific morphometric variability was observed with regard to the total body length (µm), body width (µm), stylet length (µm), distance of dosrsal oesophageal gland orifice (DEGO) from stylet base (µm), number of lip annuli, lip height (µm), distance from head to basal bulb (µm), distance of anus from anterior end (µm), tail length (µm), anal body width (µm), distance of phasmid from tail terminus (µm), number of lateral lines, width of lateral field (µm), b ratio and P % among females of R. similis. Morphometric features like m%, o% and v% of females of R. similis showed least variability. These can be considered as the stable morphometric characters for discrimination of females of R. similis. Ratios like ‘a’ and ‘c’ of females of R. similis were found moderately variable. The morphometric feature and of male i.e. distance from head to basal bulb (µm) was found least variable; while number of lip annuli and spicule length (µm) were moderately variable.  

Renal Function in Unanaesthetized River Lampreys (Lampetra FluviatilisL.): Effects of Anaesthesia, Temperature and Environmental Salinity

1983 ◽  
Vol 105 (1) ◽  
pp. 351-362 ◽  
Author(s):  
A. J. MCVICAR ◽  
J. C. RANKIN
Keyword(s):  
Renal Function ◽  
Flow Rate ◽  
Ventilation Rate ◽  
Urine Flow ◽  
The Body ◽  
Urine Flow Rate ◽  
Flow Rates ◽  
Gill Ventilation ◽  
Daily Excretion ◽  
The Mean

1. Improved estimates of urine flow rates of lampreys in various salinities were obtained by the collection of urine for periods of up to 48 h from minimally-stressed, unanaesthetized fish, following catheterization of the urinogenital papilla. 2. The mean urine flow rate of freshwater lampreys was 200.7 ±14.3 ml kg−1 day−1. 3. Urine flow in freshwater lampreys was correlated with spontaneous changes in gill ventilation rate. MS222 anaesthesia reduced both ventilation and urine flow rates, but pronounced effects were only observed at concentrations greater than those needed to induce light anaesthesia (50–55 mg 1−1). Urine flow rate in unanaesthetized fish was extremely sensitive to rapid (6°Ch−1) changes in temperature and Q10 (6–16°C) was approximately 5. 4. Urine flow rate decreased rapidly as the osmotic difference between the body fluids and environment approached zero, and the rate of flow in 30% seawater lampreys was only 7.6% that of freshwater fish. 5. There was no evidence for an effect of environmental calcium concentration on branchial osmotic permeability. 6. Extensive tubular reabsorption of ions occurred in freshwater lampreys. The total daily excretion rate of sodium ions generally decreased in salinities hyperosmotic to the plasma, indicating enhanced reabsorption, but secretion of magnesium and sulphate ions was greatly increased. Urine osmolarity was significantly increased in lampreys in hyperosmotic salinities. 7. Present data compare favourably with data obtained previously from anaesthetized animals, indicating that renal function in lampreys is not significantly impaired by light MS222 anaesthesia.

Head waving in Aplysia californica. I. Behavioural characterization of searching movements.

1994 ◽  
Vol 195 (1) ◽  
pp. 35-51
Author(s):  
F M Kuenzi ◽  
T J Carew
Keyword(s):  
Body Movement ◽  
Aplysia Californica ◽  
The Body ◽  
Head Region ◽  
Discrete Movements ◽  
Vertical Movements ◽  
Searching Behaviour ◽  
Neural Organization ◽  
Discrete Movement ◽  
The Individual

Searching is an important component of several types of goal-directed behaviour. In soft-bodied animals, searching behaviour can appear quite complex because the range of body movement is not constrained by joints, limbs or muscles with discrete areas of origin and insertion. In addition, animals exhibiting this type of behaviour utilize their maximum freedom of movement. In this paper, we describe the head-waving searching behaviour of the sea hare Aplysia californica by characterizing patterns of movements and the changes in body shape that underlie these movements. A bout of head waving consists of a series of discrete movements separated by pauses. Each discrete movement lasts 4-10s and is directed either horizontally or vertically with respect to stationary part of the animal. Large movements, such as bending from the extreme right to the extreme left, consist of a series of these shorter movements separated by pauses lasting 1-2s. In all head-waving movements, the transverse axis of the head is kept relatively parallel with the substratum. Thus, vertical movements require only bending of the body, whereas horizontal movements require twisting of the body, particularly when the posture is more erect. During head waving, the anterior two-thirds of the body is free to move, but most of the bending occurs immediately posterior to the head region. There is no periodicity of movements within a bout of head waving, although isolated instances of repeated movements are sometimes observed. Therefore, although the individual movements during head waving are relatively simple, the absence of a patterned sequence accounts for the complexity of the overall behaviour. These observations both constrain models of the neural organization of head waving and provide criteria for categorizing head-waving movements in further behavioural and physiological studies.

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